Navigation of lead extraction—is it possible? Impact of preprocedural electrocardiogram-triggered computed tomography on navigation of lead extraction

Navigation of lead extraction—is it possible? Impact of preprocedural... Abstract OBJECTIVES As the number of transvenous lead extractions continues to increase, preprocedural protocols for this procedure must be assessed. The objective of this study was to determine whether an electrocardiogram (ECG)-triggered computed tomography (Et-CT) with three-dimensional (3D) reconstructions could aid lead extractors in choosing the optimal tools to improve procedural success and avoid complications. METHODS In this study, 31 patients scheduled for transvenous lead extraction underwent a preprocedural Et-CT between January 2016 and May 2017. Both 3D-reconstructions and the two-dimensional files were reviewed for possible lead adhesions, calcifications, migrations or perforations. RESULTS Mean age was 46.7 ± 14.0 years. Seventy-one percent of patients were men, and 29.0% had undergone prior cardiac surgery. Indications for extraction included infection (n = 18, 58.1%), lead dysfunction (n = 8, 25.8%), upgrade (n = 3, 9.7%), severe tricuspid regurgitation (n = 1, 3.2%) and superior vena cava occlusion (n = 1, 3.2%). Eighteen patients had an implantable cardioverter defibrillator (58.1%). Sixty-eight of 70 targeted leads were extracted with a mean of 2.2 leads per patient and an average lead age of 109.3 ± 58.7 months. Et-CT files supported transvenous lead extraction by revealing possible adhesions in 16 patients, 5 perforations and 2 venous occlusions. Lead extraction was performed using the excimer laser, mechanical tools and femoral snares. Complete procedural success was achieved in 93.5% (n = 29) of cases. Clinical success was 100%, and intraoperative mortality was 0%. CONCLUSIONS A preprocedural Et-CT with 3D reconstructions can help to visualize lead alignment and identify abnormalities that may foreshadow procedural difficulties. A preprocedural Et-CT may therefore aid lead extractors in choosing the optimal extraction tool and strategy. Transvenous lead extraction, Computed tomography, Laser sheath, Mechanical tool, Implantable cardioverter defibrillator leads, Pacemaker leads INTRODUCTION The use of cardiac implantable electronic devices has increased significantly over the past several decades [1–3]. This increased number of implanted devices has paralleled a growing need for transvenous lead extraction (TLE), mainly due to lead failures and device infections. While advancement of TLE techniques has allowed for safer and more successful extractions, the procedure is still associated with morbidity and mortality [4–7], particularly in elderly, multimorbid patients with several, chronically implanted leads. The most feared complications in these complex cases are vascular tears of the superior vena cava (SVC) and cardiac avulsion. To address these potential complications, different TLE tools have been developed such as simple manual traction stylets, telescoping sheaths, femoral snares and laser-powered sheaths. However, despite years of experience and advancements in TLE, there is still no recommendation on the optimal extraction approach, tool and technique based on each patient’s unique risk. Moreover, no guideline exists on when an operator should crossover from one extraction tool to another during a procedure [1, 8]. The objective of this study was to investigate whether preprocedural electrocardiogram (ECG)-triggered computed tomography (Et-CT) imaging followed by three-dimensional (3D) reconstruction using a specialized software could guide TLE operators both in visualizing anatomical and/or lead abnormalities that pose potential risks and in choosing the optimal tool to achieve procedural success and avoid complications. MATERIALS AND METHODS Patient selection Between January 2016 and May 2017, we performed a preoperative Et-CT in 31 high-risk cases undergoing TLE at the University Heart Center Hamburg, University Hospital Eppendorf, Hamburg, Germany. The total number of TLEs performed during the study period was 80. Indications for lead extraction, clinical outcomes and complications were classified based on the 2009 Heart Rhythm Society (HRS) Expert Consensus document [8]. Complete procedural success was defined as removal of all target leads and all lead material from the vascular space, with the absence of any permanently disabling complication or procedure-related death. Clinical success was defined as removal of all targeted leads and lead material from the vascular space or retention of a small portion of the lead that does not negatively impact the outcome goals of the procedure. Patients were classified as high risk and considered for an Et-CT study if they fulfilled any of the following characteristics: low body mass index, female patients, low left ventricular ejection fraction, implantable cardioverter defibrillator (ICD) leads, dual-coil ICD leads, multiple indwelling leads (≥4) or leads at least >4 years [9]. In addition to the above-mentioned criteria, we selected patients for an Et-CT study if the preoperative venography revealed aggressive calcified adhesions or venous occlusions or if the chest X-ray was suspicious for perforation or lead migration. Computed tomography imaging protocol Our Et-CT protocol had been established in a previous study investigating the feasibility of a preprocedural Et-CT in 89 patients with cardiac implantable electronic devices undergoing transcatheter aortic valve replacement. In the protocol, the two-dimensional (2D) and 3D Et-CT reconstructions were investigated for lead adhesions, calcifications and perforations. Only 58 of the 89 Et-CTs were suitable for 2D and 3D analysis due to either the CT scan window (different window of interest in transcatheter aortic valve replacement patients) or the timing between image acquisition and the administration of intravenous dye solution. To address these issues in our current study, we adapted the CT window of interest and the timing of intravenous dye solution administration for our TLE Et-CT protocol. Additionally, we developed an algorithm for 3D CT analysis prior to TLE. All Et-CT examinations were performed on a 256-multidetector computed tomography scanner (Philips iCT, Philips Healthcare, Netherlands). A prospective ECG-triggered acquisition was performed in a single breath-hold with image acquisition at the 70% interval. Et-CT scans started from the lower neck through the heart apex for evaluation of central veins and heart chambers. Image acquisition was initiated 70 s after the intravenous administration of 120 ml non-ionic contrast medium containing 400 mg I/ml (Imeron 400, Bracco Imaging, Italy) injected at 4 ml/s. Scans were only performed at a heart rate of <80 bpm. Patients with a heart rate >80 bpm received preprocedural medication of 50–100 mg atenolol. Image analysis One radiologist, who was not involved in the planning or initial clinical interpretation of the scheduled patients, independently evaluated the 2D imaging files. He was unaware of any suspected lead abnormalities. Our lead extraction team consisting of a cardiac surgeon and a cardiologist performed the 3D reconstruction by using a specialized software (3mensio Structural Heart™, Pie Medical Imaging, Maastricht, Netherlands). The 2D and the 3D reconstruction files were investigated for the following predefined abnormalities: lead adhesions (interlead and vascular adhesions), lead migrations, perforations, calcifications, venous occlusions or stenosis. The term ‘lead migration’ describes transmural extravascular migration of leads or parts of a lead at the vascular sites. Extraction technique All cases were performed in a hybrid suite under general anaesthesia by the lead extraction team with the aid of fluoroscopy, transoesophageal echocardiography and intra-arterial blood pressure monitoring. Patients were prepared for emergent sternotomy with cardiopulmonary bypass on standby. We started every procedure by placing 1 femoral arterial sheath and 2 venous femoral sheaths for safety reasons (temporary pacing, occlusion balloon or cardiopulmonary bypass) and to introduce a 5-Fr pigtail catheter into the right internal jugular vein. For extraction via the subclavian route, we used 14-Fr or 16-Fr 80-Hz excimer laser sheaths (GlideLight™, Spectranetics Corporation, Colorado Springs, CO, USA), mostly as a single-sheath technique without using outer sheaths as previously described by our group [10]. In the event of failure, a selective venography via the pigtail catheter was performed to visualize the size and shape of the adhesions. In these cases, we switched to 11-Fr or 13-Fr mechanical tools (TightRail™; Spectranetics or Evolution® RL Mechanical Dilator Sheath; Cook Medical Inc., Bloomington, IN, USA). In cases involving fractured or damaged leads following the use of powered tools, we crossed over to a femoral approach, utilizing different snares as a last step of the TLE procedure. Statistical analysis Data were prospectively collected via our institution’s ongoing TLE registry. Continuous variables are expressed as mean ± standard deviation for normal distributions and as median and interquartile ranges for other distributions. Categorical variables are summarized as counts and percentages. Statistical analysis tested whether the additional use of mechanical tools was related to any of the following variables: age, gender, chronic renal insufficiency, total number of leads and remarkable findings on Et-CT. The Fisher’s exact test was applied for small sample sizes (expected cell sizes <5), and the χ2 test was applied for all other samples. A 2-tailed P-value of 0.05 was considered statistically significant. Due to the small cohort, results are of an exploratory and descriptive character. An independent statistician performed all analyses using a statistical software package (IBM SPSS version 24, SPSS Inc. an IBM Company, Chicago, IL, USA). RESULTS Patients and leads For the 31 patients, the mean age was 46.7 ± 14.0 years. Seventy-one percent of patients were men. Twelve patients had a left ventricular ejection fraction <30% (38.7%) and 9 (29.0%) patients had undergone prior cardiac surgery. Renal insufficiency was present in 11 (36.5%) patients, of which 1 patient was on regular haemodialysis. A pacemaker (PM) was implanted in 13 patients, and an ICD was implanted in the remaining 18 patients (including 12 cardiac resynchronization therapy defibrillator patients). The majority of the devices were left sided (n = 23). Seven devices were on the right side, and 1 patient had leads implanted on both sides. Thirteen patients were PM dependent, of which 3 patients required a temporary transcutaneous pacing system. Patient baseline characteristics are presented in Table 1. Table 1: Baseline demographics and clinical characteristics of the study population Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) BMI: body mass index; CRT-D: cardiac resynchronization therapy defibrillator; ICD: implantable cardioverter defibrillator; LVEF: left ventricular ejection fraction; NYHA: New York Heart Association; SD: standard deviation; SVC: superior vena cava. Table 1: Baseline demographics and clinical characteristics of the study population Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) BMI: body mass index; CRT-D: cardiac resynchronization therapy defibrillator; ICD: implantable cardioverter defibrillator; LVEF: left ventricular ejection fraction; NYHA: New York Heart Association; SD: standard deviation; SVC: superior vena cava. A total of 80 leads were present in our cohort, including 23 atrial leads, 20 right ventricular pacing leads, 26 right ventricular ICD leads (19 dual-coil leads) and 11 coronary sinus leads. The mean dwell time of all leads was 113.1 ± 54.2 months, and the mean dwell time of all extracted leads was 109.3 ± 58.7 months. Active lead tip fixation was present in 26 (83.9%) patients. The remaining 5 patients had leads with active and passive fixation mechanisms. Sixty-eight of the 70 targeted leads were successfully removed (mean of 2.2 leads per patient). We were unable to extract 2 abandoned ICD leads in a patient scheduled for a cardiac resynchronization therapy defibrillator upgrade because of a damaged lumen. However, this did not negatively impact the clinical success of the procedure. Electrocardiogram-triggered computed tomography analysis The mean area–dose product of the Et-CT was 533.2 ± 327.2 cGy ⋅ cm2. Due to poor imaging quality, 1 CT scan was excluded from further analysis. Analysis of 2D-CT and 3D reconstructions using 3mensio Structural Heart (Pie Medical Imaging) (Table 2) was unremarkable in 7 (23.3%) patients. Adhesions between the leads (interlead adhesions) were the most common finding (n = 16, 53.3%) (Fig. 1). Interlead adhesions were observed in 16 patients when using a combination of 2D and 3D CT analysis and in 13 patients when using 2D CT files only. Et-CT with 3D imaging was suspicious for vascular adhesion at the SVC in 1 patient (in 2 patients with 2D CT analysis). In 1 patient (6 patients with 2D CT analysis), Et-CT with 3D imaging depicted both interlead adhesions and vascular adhesions. We could not determine the grade of adhesions due to the lack of standardization in differentiating between metallic artefacts and true adhesions. An independent radiologist performed analysis of the 2D-CT files for calcification around the leads in patients where additional mechanical tools had been used for TLE. Table 2: Analysis of the Et-CT prior to lead extraction Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 2D: two-dimensional; 3D: three-dimensional; CI: confidence interval; Et-CT: electrocardiogram-triggered computed tomography. Table 2: Analysis of the Et-CT prior to lead extraction Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 2D: two-dimensional; 3D: three-dimensional; CI: confidence interval; Et-CT: electrocardiogram-triggered computed tomography. Figure 1: View largeDownload slide Three-dimensional reconstruction using 3mensio Structural Heart™ showing interlead adhesions in an implantable cardioverter defibrillator and a pacemaker-dependent patient (A, B). (C) Interlead adhesions in the superior vena cava in a transverse two-dimensional computed tomography reconstruction. Figure 1: View largeDownload slide Three-dimensional reconstruction using 3mensio Structural Heart™ showing interlead adhesions in an implantable cardioverter defibrillator and a pacemaker-dependent patient (A, B). (C) Interlead adhesions in the superior vena cava in a transverse two-dimensional computed tomography reconstruction. Et-CT was suspicious for myocardial perforation in 5 (16.6%) patients (Fig. 2), with extrusion of the lead tip beyond the myocardial border. None of these patients had abnormal pacing impedances or capture thresholds. We did not apply a 5-point scale to grade the 2D-CT files for possible perforation as proposed by Balabanoff et al. [11]. Venous occlusion was seen in 2 (6.7%) patients (Table 3). A combination of 2D- and 3D-reconstruction analysis showed no clear signs of lead migration, whereas 2D-CT analysis was consistent with migration in 1 patient. Table 3: Number of targeted leads, mean lead age, preprocedural CT findings and extraction methods illustrated for each patient Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser a CT files of TLE cases in which we had to use mechanical tools were evaluated for calcifications around the leads. b Due to bad quality, we were not able to perform 2D and 3D CT analysis in patient number 8. 2D: two-dimensional; 3D: three-dimensional; CT: computed tomography; TLE: transvenous lead extraction. Table 3: Number of targeted leads, mean lead age, preprocedural CT findings and extraction methods illustrated for each patient Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser a CT files of TLE cases in which we had to use mechanical tools were evaluated for calcifications around the leads. b Due to bad quality, we were not able to perform 2D and 3D CT analysis in patient number 8. 2D: two-dimensional; 3D: three-dimensional; CT: computed tomography; TLE: transvenous lead extraction. Figure 2: View largeDownload slide Example of a patient with possible myocardial perforation of the right ventricular pacing lead in a three-dimensional reconstructed computed tomography (CT) file (A) and the two-dimensional CT file (B). Figure 2: View largeDownload slide Example of a patient with possible myocardial perforation of the right ventricular pacing lead in a three-dimensional reconstructed computed tomography (CT) file (A) and the two-dimensional CT file (B). Procedural data Mean procedural duration was 123.1 ± 58.0 min. The 80-Hz excimer laser (14- and 16-Fr sheaths) was used in 18 (58.1%) patients, and the Cook Evolution RL (13-Fr sheath) was used in 2 (6.5%) patients. In the remaining 11 patients, TLE was performed using a combination of the excimer laser, powered mechanical tools [Cook Evolution RL (13 Fr) or Spectranetics Tight rail (11 Fr)], and/or femoral snares (Table 4). The additional use of mechanical tools (in addition to the excimer laser) was not related to age (P = 0.832, U-test), gender (P > 0.999, Fisher’s exact test), renal insufficiency (P = 0.248, Fisher’s exact test), total number of implanted leads (P = 0.172, χ2 test) or the existence of interlead adhesions in the Et-CT (P = 0.538, Fisher’s exact test). Table 4: Procedural data and outcomes Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) CI: confidence interval; SD: standard deviation. Table 4: Procedural data and outcomes Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) CI: confidence interval; SD: standard deviation. Clinical success was achieved in all patients, and complete procedural success was achieved in 29 (93.5%) patients. In 1 of the 2 patients in which procedural success was not achieved, we were unable to stabilize 2 abandoned ICD leads with lead locking devices (LLD™; Spectranectics, Colorado Springs, USA). We did not attempt further extraction manoeuvres because the indication for TLE was an upgrade, which was successfully performed by extracting the newest (active) ICD lead. The other case involved TLE for atrial and ventricular lead dysfunction. After extracting the ICD lead and implanting a new ICD lead, we were unable to implant a new atrial lead from the left side because of aggressive adhesions and totally occluded subclavian–innominate veins. Therefore, we had to implant a new atrial lead from the right side. Two minor complications (1 pocket haematoma and 1 pneumothorax) and 1 major complication occurred after TLE. The major complication was unrelated to TLE as it involved resuscitation for an unknown reason 8 h post-TLE after removing a femoral compression device. No intraprocedural complications were observed. Two deaths unrelated to TLE occurred during the hospital stay due to septic shock in 1 patient and hypoxic encephalopathy after resuscitation in the other patient. DISCUSSION Our data showed that an Et-CT prior to TLE was able to visualize lead alignment (Fig. 3) from the subclavian vein to the heart as well as detect lead abnormalities such as vascular adhesions, interlead adhesions, myocardial perforations, venous occlusions and calcification. These findings have been described to some extent in a case report and in a study by Lewis etal. [12, 13] in 30 patients who received a preprocedural ECG-gated CT. However, while Lewis et al. focused on identifying significant perforations and lead adhesions to central venous structures to assess the risk for complications during TLE, they did not consider the potential role of Et-CT in navigating or planning TLE. Abnormalities seen on Et-CT may not only identify patients at a higher risk for complications during TLE but also help to optimize and refine the intraoperative TLE setting. In high-risk patients with severe interlead adhesions and/or adhesions at the SVC predisposing patients for SVC tears, the use of femoral sheaths and a pigtail catheter in the internal jugular vein should be routinely applied to safely manage a tear with rescue devices. Another option in these high-risk TLE patients is the prophylactic placement of an endovascular occlusion balloon in the vena cava [14]. Due to signs of perforation and adhesion seen on ET-CT, we utilized an endovascular balloon in addition to our routine intraoperative setting as a backup in some patients with very old leads. Therefore, an Et-CT can increase the safety of TLE, especially in patients with infections where TLE is mandatory. In contrast to other groups [13], we did not reject TLE in case of a possible perforation on Et-CT, but we were more vigilant about perioperative pericardial effusion resulting in pericardiocentesis. Figure 3: View largeDownload slide Electrocardiogram-triggered computed tomography prior to transvenous lead extraction after three-dimensional reconstruction using 3mensio Structural Heart™ in a cardiac resynchronization therapy defibrillator patient (A) and a pacemaker-dependent patient showing alignment of the leads within the right ventricle and the coronary sinus (B). Figure 3: View largeDownload slide Electrocardiogram-triggered computed tomography prior to transvenous lead extraction after three-dimensional reconstruction using 3mensio Structural Heart™ in a cardiac resynchronization therapy defibrillator patient (A) and a pacemaker-dependent patient showing alignment of the leads within the right ventricle and the coronary sinus (B). A systemically analysed Et-CT prior to TLE may help in choosing the optimal extraction tool and approach for TLE. Our group [15] and other groups [7, 16] have described promising results of TLE with the 80-Hz excimer laser as the sole extraction tool in patients with significantly shorter lead dwell times than in our present study (50.3 ± 18.4 months vs 109.3 ± 58.7 months). However, the excimer laser is sometimes unsuccessful as an exclusive tool in patients with older leads and calcified interlead or vascular adhesions. In these cases, complete TLE success can only be achieved with the additional use of powered mechanical tools with rotating threaded tip sheaths. Our study is the first to systematically evaluate preprocedural 2D CT files and 3D reconstruction files of an Et-CT using 3mensio Structural Heart for these adhesions and other predefined abnormalities. Identification of strong and severely calcified adhesions between the leads or adjacent to the venous wall before the actual extraction may guide the clinician in planning the optimal strategy and extraction tool for the procedure. This is especially helpful when deciding to switch from one tool to another (from the laser sheath to a mechanical tool). However, identification of calcifications is still the most challenging task of preprocedural analysis as it requires differentiation between chalk and metallic streak artefacts. Due to the lack of an exact definition and classification of interlead adhesions, vascular adhesions and calcifications on Et-CT, further improvement of image analysis using CT raw data and the development of standards are necessary. In our first small series, we were, therefore, unable to detect a relationship between the additional use of mechanical tools and interlead adhesions in patients where the excimer laser as an exclusive tool failed. Large multicentre studies and further refinement of image analysis are now necessary to evaluate whether it is possible to choose the optimal extraction tool depending on the type of interlead and vascular adhesions seen on preprocedural Et-CT. The development of image integration systems for the hybrid operating suite may also allow integration of Et-CTs into fluoroscopy systems as has already been established in electrophysiology labs that integrate CTs and magnetic resonance imaging into mapping systems. Integration of Et-CTs with intraoperatively performed venography, live fluoroscopy and 3D-transoesophageal echocardiography could enable us to perform real-time TLE navigation in the future. As with any X-ray-based imaging modality, there is a concern about radiation exposure. However, given the potential fatal complications of TLE, we believe the benefits of an Et-CT outweigh the risks of the additional radiation exposure in high-risk TLE patients. In low-risk patients with a short lead dwell time, a preprocedural Et-CT is probably not required. Limitations The major limitation of this study is that it is a small, non-randomized, retrospective, single-centre study. The only way to evaluate the potential value of an Et-CT would be a prospective clinical trial comparing procedural data and outcome of patients with an Et-CT prior to TLE with a similar group of patients without an Et-CT. Therefore, a definite statement considering the value of an Et-CT cannot be made based on this preliminary work. Furthermore, only patients deemed to be at high risk received an Et-CT. Due to limited data on risk factors of patients undergoing TLE [17], a standard definition of high-risk TLE patients has not yet been established. Thus, the definition of high risk is centre specific. Additionally, one of the major limitations in radiological analysis was the exact differentiation of true calcifications and interlead adhesions from metallic streak artefacts as well as the classification of the severity of interlead adhesions. Although this limitation may be overcome in future, an Et-CT is unable to distinguish leads that are adjacent to the SVC lateral wall from the ones that are embedded in the wall. Other intraoperative imaging techniques such as 3D transoesophageal echocardiography offer real-time, dynamic monitoring and may provide such information. CONCLUSION A preprocedural Et-CT followed by 2D and 3D reconstruction using a specialized software may offer the potential to identify lead abnormalities that may foreshadow complications during TLE. Integrating a special Et-CT into the preprocedural workflow of patients undergoing TLE can help both to reduce complications by optimizing the intraoperative setting and to achieve complete procedural success by choosing the optimal extraction tool for each patient. Large, multicentre studies are warranted to prospectively evaluate whether an Et-CT has an impact on outcome and complications of TLE. Conflict of interest: Samer Hakmi is a consultant/training proctor of Spectranetics Corp. All other authors declared no conflict of interest. REFERENCES 1 Buiten MS , van der Heijden AC , Schalij MJ , van Erven L. How adequate are the current methods of lead extraction? A review of the efficiency and safety of transvenous lead extraction methods . Europace 2015 ; 17 : 689 – 700 . Google Scholar CrossRef Search ADS PubMed 2 Greenspon AJ , Patel JD , Lau E , Ochoa JA , Frisch DR , Ho RT et al. Trends in permanent pacemaker implantation in the United States from 1993 to 2009: increasing complexity of patients and procedures . J Am Coll Cardiol 2012 ; 60 : 1540 – 5 . Google Scholar CrossRef Search ADS PubMed 3 Kurtz SM , Ochoa JA , Lau E , Shkolnikov Y , Pavri BB , Frisch D et al. Implantation trends and patient profiles for pacemakers and implantable cardioverter defibrillators in the United States: 1993-2006 . Pacing Clin Electrophysiol 2010 ; 33 : 705 – 11 . Google Scholar CrossRef Search ADS PubMed 4 Maytin M , Jones SO , Epstein LM. Long-term mortality after transvenous lead extraction . Circ Arrhythm Electrophysiol 2012 ; 5 : 252 – 7 . Google Scholar CrossRef Search ADS PubMed 5 Wilkoff BL , Byrd CL , Love CJ , Hayes DL , Sellers TD , Schaerf R et al. Pacemaker lead extraction with the laser sheath: results of the pacing lead extraction with the excimer sheath (PLEXES) trial . J Am Coll Cardiol 1999 ; 33 : 1671 – 6 . Google Scholar CrossRef Search ADS PubMed 6 Wilkoff BL , Love CJ , Byrd CL , Bongiorni MG , Carrillo RG , Crossley GH 3rd et al. Transvenous lead extraction: Heart Rhythm Society expert consensus on facilities, training, indications, and patient management: this document was endorsed by the American Heart Association (AHA) . Heart Rhythm 2009 ; 6 : 1085 – 104 . Google Scholar CrossRef Search ADS PubMed 7 Wazni O , Epstein LM , Carrillo RG , Love C , Adler SW , Riggio DW et al. Lead extraction in the contemporary setting: the LExICon study: an observational retrospective study of consecutive laser lead extractions . J Am Coll Cardiol 2010 ; 55 : 579 – 86 . Google Scholar CrossRef Search ADS PubMed 8 Maisel WH , Hauser RG , Hammill SC , Hauser RG , Ellenbogen KA , Epstein AE et al. Recommendations from the Heart Rhythm Society task force on lead performance policies and guidelines: developed in collaboration with the American College of Cardiology (ACC) and the American Heart Association (AHA) . Heart Rhythm 2009 ; 6 : 869 – 85 . Google Scholar CrossRef Search ADS PubMed 9 Wilkoff BL , Kennergren C , Love CJ , Kutalek SP , Epstein LM , Carrillo R. Bridge to surgery: best practice protocol derived from early clinical experience with the Bridge Occlusion Balloon. Federated Agreement from the Eleventh Annual Lead Management Symposium . Heart Rhythm 2017 ; 14 : 1574 – 8 . Google Scholar CrossRef Search ADS PubMed 10 Hakmi S , Pecha S , Sill B , Reiter B , Willems S , Aydin MA et al. Initial experience of pacemaker and implantable cardioverter defibrillator lead extraction with the new GlideLight 80 Hz laser sheaths . Interact CardioVasc Thorac Surg 2014 ; 18 : 56 – 60 . Google Scholar CrossRef Search ADS PubMed 11 Balabanoff C , Gaffney CE , Ghersin E , Okamoto Y , Carrillo R , Fishman JE. Radiographic and electrocardiography-gated noncontrast cardiac CT assessment of lead perforation: modality comparison and interobserver agreement . J Cardiovasc Comput Tomogr 2014 ; 8 : 384 – 90 . Google Scholar CrossRef Search ADS PubMed 12 Sidiqi I , Ghalayini W , Zughaib T , Machado C. Use of computed tomography as a screening modality before lead extraction for patients affected by failure of the recalled riata leads: a case report . J Innovations Card Rhythm Manag 2013 ; 4 : 1325 – 7 . 13 Lewis RK , Pokorney SD , Greenfield RA , Hranitzky PM , Hegland DD , Schroder JN et al. Preprocedural ECG-gated computed tomography for prevention of complications during lead extraction . Pacing Clin Electrophysiol 2014 ; 37 : 1297 – 305 . Google Scholar CrossRef Search ADS PubMed 14 Tsang DC , Azarrafiy R , Pecha S , Reichenspurner H , Carrillo RG , Hakmi S. Long-term outcomes of prophylactic placement of an endovascular balloon in the vena cava for high-risk transvenous lead extractions . Heart Rhythm 2017 ; 14 : 1833 – 8 . Google Scholar CrossRef Search ADS PubMed 15 Pecha S , Yildirim Y , Gosau N , Aydin MA , Willems S , Treede H et al. Laser lead extraction allows for safe and effective removal of single- and dual-coil implantable cardioverter defibrillator leads: a single-centre experience over 12 years . Interact CardioVasc Thorac Surg 2017 ; 24 : 77 – 81 . Google Scholar CrossRef Search ADS PubMed 16 Tanawuttiwat T , Gallego D , Carrillo RG. Lead extraction experience with high frequency excimer laser . Pacing Clin Electrophysiol 2014 ; 37 : 1120 – 8 . Google Scholar CrossRef Search ADS PubMed 17 Fu HX , Huang XM , Zhong LI , Osborn MJ , Asirvatham SJ , Espinosa RE et al. Outcomes and complications of lead removal: can we establish a risk stratification schema for a collaborative and effective approach? Pacing Clin Electrophysiol 2015 ; 38 : 1439 – 47 . Google Scholar CrossRef Search ADS PubMed © The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices) http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png European Journal of Cardio-Thoracic Surgery Oxford University Press

Navigation of lead extraction—is it possible? Impact of preprocedural electrocardiogram-triggered computed tomography on navigation of lead extraction

Loading next page...
 
/lp/ou_press/navigation-of-lead-extraction-is-it-possible-impact-of-preprocedural-RIzGdiybQE
Publisher
Oxford University Press
Copyright
© The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
ISSN
1010-7940
eISSN
1873-734X
D.O.I.
10.1093/ejcts/ezy106
Publisher site
See Article on Publisher Site

Abstract

Abstract OBJECTIVES As the number of transvenous lead extractions continues to increase, preprocedural protocols for this procedure must be assessed. The objective of this study was to determine whether an electrocardiogram (ECG)-triggered computed tomography (Et-CT) with three-dimensional (3D) reconstructions could aid lead extractors in choosing the optimal tools to improve procedural success and avoid complications. METHODS In this study, 31 patients scheduled for transvenous lead extraction underwent a preprocedural Et-CT between January 2016 and May 2017. Both 3D-reconstructions and the two-dimensional files were reviewed for possible lead adhesions, calcifications, migrations or perforations. RESULTS Mean age was 46.7 ± 14.0 years. Seventy-one percent of patients were men, and 29.0% had undergone prior cardiac surgery. Indications for extraction included infection (n = 18, 58.1%), lead dysfunction (n = 8, 25.8%), upgrade (n = 3, 9.7%), severe tricuspid regurgitation (n = 1, 3.2%) and superior vena cava occlusion (n = 1, 3.2%). Eighteen patients had an implantable cardioverter defibrillator (58.1%). Sixty-eight of 70 targeted leads were extracted with a mean of 2.2 leads per patient and an average lead age of 109.3 ± 58.7 months. Et-CT files supported transvenous lead extraction by revealing possible adhesions in 16 patients, 5 perforations and 2 venous occlusions. Lead extraction was performed using the excimer laser, mechanical tools and femoral snares. Complete procedural success was achieved in 93.5% (n = 29) of cases. Clinical success was 100%, and intraoperative mortality was 0%. CONCLUSIONS A preprocedural Et-CT with 3D reconstructions can help to visualize lead alignment and identify abnormalities that may foreshadow procedural difficulties. A preprocedural Et-CT may therefore aid lead extractors in choosing the optimal extraction tool and strategy. Transvenous lead extraction, Computed tomography, Laser sheath, Mechanical tool, Implantable cardioverter defibrillator leads, Pacemaker leads INTRODUCTION The use of cardiac implantable electronic devices has increased significantly over the past several decades [1–3]. This increased number of implanted devices has paralleled a growing need for transvenous lead extraction (TLE), mainly due to lead failures and device infections. While advancement of TLE techniques has allowed for safer and more successful extractions, the procedure is still associated with morbidity and mortality [4–7], particularly in elderly, multimorbid patients with several, chronically implanted leads. The most feared complications in these complex cases are vascular tears of the superior vena cava (SVC) and cardiac avulsion. To address these potential complications, different TLE tools have been developed such as simple manual traction stylets, telescoping sheaths, femoral snares and laser-powered sheaths. However, despite years of experience and advancements in TLE, there is still no recommendation on the optimal extraction approach, tool and technique based on each patient’s unique risk. Moreover, no guideline exists on when an operator should crossover from one extraction tool to another during a procedure [1, 8]. The objective of this study was to investigate whether preprocedural electrocardiogram (ECG)-triggered computed tomography (Et-CT) imaging followed by three-dimensional (3D) reconstruction using a specialized software could guide TLE operators both in visualizing anatomical and/or lead abnormalities that pose potential risks and in choosing the optimal tool to achieve procedural success and avoid complications. MATERIALS AND METHODS Patient selection Between January 2016 and May 2017, we performed a preoperative Et-CT in 31 high-risk cases undergoing TLE at the University Heart Center Hamburg, University Hospital Eppendorf, Hamburg, Germany. The total number of TLEs performed during the study period was 80. Indications for lead extraction, clinical outcomes and complications were classified based on the 2009 Heart Rhythm Society (HRS) Expert Consensus document [8]. Complete procedural success was defined as removal of all target leads and all lead material from the vascular space, with the absence of any permanently disabling complication or procedure-related death. Clinical success was defined as removal of all targeted leads and lead material from the vascular space or retention of a small portion of the lead that does not negatively impact the outcome goals of the procedure. Patients were classified as high risk and considered for an Et-CT study if they fulfilled any of the following characteristics: low body mass index, female patients, low left ventricular ejection fraction, implantable cardioverter defibrillator (ICD) leads, dual-coil ICD leads, multiple indwelling leads (≥4) or leads at least >4 years [9]. In addition to the above-mentioned criteria, we selected patients for an Et-CT study if the preoperative venography revealed aggressive calcified adhesions or venous occlusions or if the chest X-ray was suspicious for perforation or lead migration. Computed tomography imaging protocol Our Et-CT protocol had been established in a previous study investigating the feasibility of a preprocedural Et-CT in 89 patients with cardiac implantable electronic devices undergoing transcatheter aortic valve replacement. In the protocol, the two-dimensional (2D) and 3D Et-CT reconstructions were investigated for lead adhesions, calcifications and perforations. Only 58 of the 89 Et-CTs were suitable for 2D and 3D analysis due to either the CT scan window (different window of interest in transcatheter aortic valve replacement patients) or the timing between image acquisition and the administration of intravenous dye solution. To address these issues in our current study, we adapted the CT window of interest and the timing of intravenous dye solution administration for our TLE Et-CT protocol. Additionally, we developed an algorithm for 3D CT analysis prior to TLE. All Et-CT examinations were performed on a 256-multidetector computed tomography scanner (Philips iCT, Philips Healthcare, Netherlands). A prospective ECG-triggered acquisition was performed in a single breath-hold with image acquisition at the 70% interval. Et-CT scans started from the lower neck through the heart apex for evaluation of central veins and heart chambers. Image acquisition was initiated 70 s after the intravenous administration of 120 ml non-ionic contrast medium containing 400 mg I/ml (Imeron 400, Bracco Imaging, Italy) injected at 4 ml/s. Scans were only performed at a heart rate of <80 bpm. Patients with a heart rate >80 bpm received preprocedural medication of 50–100 mg atenolol. Image analysis One radiologist, who was not involved in the planning or initial clinical interpretation of the scheduled patients, independently evaluated the 2D imaging files. He was unaware of any suspected lead abnormalities. Our lead extraction team consisting of a cardiac surgeon and a cardiologist performed the 3D reconstruction by using a specialized software (3mensio Structural Heart™, Pie Medical Imaging, Maastricht, Netherlands). The 2D and the 3D reconstruction files were investigated for the following predefined abnormalities: lead adhesions (interlead and vascular adhesions), lead migrations, perforations, calcifications, venous occlusions or stenosis. The term ‘lead migration’ describes transmural extravascular migration of leads or parts of a lead at the vascular sites. Extraction technique All cases were performed in a hybrid suite under general anaesthesia by the lead extraction team with the aid of fluoroscopy, transoesophageal echocardiography and intra-arterial blood pressure monitoring. Patients were prepared for emergent sternotomy with cardiopulmonary bypass on standby. We started every procedure by placing 1 femoral arterial sheath and 2 venous femoral sheaths for safety reasons (temporary pacing, occlusion balloon or cardiopulmonary bypass) and to introduce a 5-Fr pigtail catheter into the right internal jugular vein. For extraction via the subclavian route, we used 14-Fr or 16-Fr 80-Hz excimer laser sheaths (GlideLight™, Spectranetics Corporation, Colorado Springs, CO, USA), mostly as a single-sheath technique without using outer sheaths as previously described by our group [10]. In the event of failure, a selective venography via the pigtail catheter was performed to visualize the size and shape of the adhesions. In these cases, we switched to 11-Fr or 13-Fr mechanical tools (TightRail™; Spectranetics or Evolution® RL Mechanical Dilator Sheath; Cook Medical Inc., Bloomington, IN, USA). In cases involving fractured or damaged leads following the use of powered tools, we crossed over to a femoral approach, utilizing different snares as a last step of the TLE procedure. Statistical analysis Data were prospectively collected via our institution’s ongoing TLE registry. Continuous variables are expressed as mean ± standard deviation for normal distributions and as median and interquartile ranges for other distributions. Categorical variables are summarized as counts and percentages. Statistical analysis tested whether the additional use of mechanical tools was related to any of the following variables: age, gender, chronic renal insufficiency, total number of leads and remarkable findings on Et-CT. The Fisher’s exact test was applied for small sample sizes (expected cell sizes <5), and the χ2 test was applied for all other samples. A 2-tailed P-value of 0.05 was considered statistically significant. Due to the small cohort, results are of an exploratory and descriptive character. An independent statistician performed all analyses using a statistical software package (IBM SPSS version 24, SPSS Inc. an IBM Company, Chicago, IL, USA). RESULTS Patients and leads For the 31 patients, the mean age was 46.7 ± 14.0 years. Seventy-one percent of patients were men. Twelve patients had a left ventricular ejection fraction <30% (38.7%) and 9 (29.0%) patients had undergone prior cardiac surgery. Renal insufficiency was present in 11 (36.5%) patients, of which 1 patient was on regular haemodialysis. A pacemaker (PM) was implanted in 13 patients, and an ICD was implanted in the remaining 18 patients (including 12 cardiac resynchronization therapy defibrillator patients). The majority of the devices were left sided (n = 23). Seven devices were on the right side, and 1 patient had leads implanted on both sides. Thirteen patients were PM dependent, of which 3 patients required a temporary transcutaneous pacing system. Patient baseline characteristics are presented in Table 1. Table 1: Baseline demographics and clinical characteristics of the study population Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) BMI: body mass index; CRT-D: cardiac resynchronization therapy defibrillator; ICD: implantable cardioverter defibrillator; LVEF: left ventricular ejection fraction; NYHA: New York Heart Association; SD: standard deviation; SVC: superior vena cava. Table 1: Baseline demographics and clinical characteristics of the study population Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) Patients n = 31 Demographics  Age (years), mean ± SD 46.7 ± 14.0  Male gender, n (%) 22 (71.0)  BMI (kg/m2), mean ± SD 27.0 ± 4.0 Medical history, n (%)  Prior cardiac surgery 9 (29.0)  LVEF <30% 12 (38.7)  NYHA III–IV 11 (35.5)  Diabetes mellitus 9 (29.0)  Arterial hypertension 19 (61.3)  Renal insufficiency 11 (36.5)  Pacemaker dependency 13 (41.9) Implanted devices, n (%)a  Pacemaker 13   Single chamber 3 (9.7)   Dual chamber 10 (32.3)  ICD 18   Single chamber 5 (16.1)   Dual chamber 1 (3.2)   CRT-D 12 (38.7) Indications for lead extraction, n (%)  Pocket infection 14 (45.2)  Systemic infection 4 (12.9)  Lead dysfunction 8 (25.8)  System upgrade 3 (9.7)  Severe tricuspid regurgitation 1 (3.2)  Symptomatic SVC occlusion 1 (3.2) BMI: body mass index; CRT-D: cardiac resynchronization therapy defibrillator; ICD: implantable cardioverter defibrillator; LVEF: left ventricular ejection fraction; NYHA: New York Heart Association; SD: standard deviation; SVC: superior vena cava. A total of 80 leads were present in our cohort, including 23 atrial leads, 20 right ventricular pacing leads, 26 right ventricular ICD leads (19 dual-coil leads) and 11 coronary sinus leads. The mean dwell time of all leads was 113.1 ± 54.2 months, and the mean dwell time of all extracted leads was 109.3 ± 58.7 months. Active lead tip fixation was present in 26 (83.9%) patients. The remaining 5 patients had leads with active and passive fixation mechanisms. Sixty-eight of the 70 targeted leads were successfully removed (mean of 2.2 leads per patient). We were unable to extract 2 abandoned ICD leads in a patient scheduled for a cardiac resynchronization therapy defibrillator upgrade because of a damaged lumen. However, this did not negatively impact the clinical success of the procedure. Electrocardiogram-triggered computed tomography analysis The mean area–dose product of the Et-CT was 533.2 ± 327.2 cGy ⋅ cm2. Due to poor imaging quality, 1 CT scan was excluded from further analysis. Analysis of 2D-CT and 3D reconstructions using 3mensio Structural Heart (Pie Medical Imaging) (Table 2) was unremarkable in 7 (23.3%) patients. Adhesions between the leads (interlead adhesions) were the most common finding (n = 16, 53.3%) (Fig. 1). Interlead adhesions were observed in 16 patients when using a combination of 2D and 3D CT analysis and in 13 patients when using 2D CT files only. Et-CT with 3D imaging was suspicious for vascular adhesion at the SVC in 1 patient (in 2 patients with 2D CT analysis). In 1 patient (6 patients with 2D CT analysis), Et-CT with 3D imaging depicted both interlead adhesions and vascular adhesions. We could not determine the grade of adhesions due to the lack of standardization in differentiating between metallic artefacts and true adhesions. An independent radiologist performed analysis of the 2D-CT files for calcification around the leads in patients where additional mechanical tools had been used for TLE. Table 2: Analysis of the Et-CT prior to lead extraction Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 2D: two-dimensional; 3D: three-dimensional; CI: confidence interval; Et-CT: electrocardiogram-triggered computed tomography. Table 2: Analysis of the Et-CT prior to lead extraction Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 Analysed Et-CTs (n = 30) 2D CT plus 3D reconstruction 2D CT Suspicious findings, n (%) [95% CI]  No suspicious findings 7 (23.3) [9.9–42.3] 6 (20.0) [7.7–38.6]  Adhesions 16 (53.3) [34.3–71.7] 17 (56.7) [37.4–74.5]  Migration 0 (0.0) [0.0–1.0] 1 (3.3) [0.1–17.2]  Perforation 3 (10.0) [2.1–26.5] 3 (10.0) [2.1–26.5]  Venous occlusion 2 (6.7) [0.8–22.1] 2 (6.7) [0.8–22.1]  Perforation plus adhesions 1 (3.3) [0.1–17.2] 2 (6.7) [0.8–22.1]  Possible perforation 1 (3.3) [0.1–17.2] 0 (0.0) [0.0–1.0] Location of adhesions, n  Superior vena cava 1 2  Interlead adhesions 16 13  Both 1 6 2D: two-dimensional; 3D: three-dimensional; CI: confidence interval; Et-CT: electrocardiogram-triggered computed tomography. Figure 1: View largeDownload slide Three-dimensional reconstruction using 3mensio Structural Heart™ showing interlead adhesions in an implantable cardioverter defibrillator and a pacemaker-dependent patient (A, B). (C) Interlead adhesions in the superior vena cava in a transverse two-dimensional computed tomography reconstruction. Figure 1: View largeDownload slide Three-dimensional reconstruction using 3mensio Structural Heart™ showing interlead adhesions in an implantable cardioverter defibrillator and a pacemaker-dependent patient (A, B). (C) Interlead adhesions in the superior vena cava in a transverse two-dimensional computed tomography reconstruction. Et-CT was suspicious for myocardial perforation in 5 (16.6%) patients (Fig. 2), with extrusion of the lead tip beyond the myocardial border. None of these patients had abnormal pacing impedances or capture thresholds. We did not apply a 5-point scale to grade the 2D-CT files for possible perforation as proposed by Balabanoff et al. [11]. Venous occlusion was seen in 2 (6.7%) patients (Table 3). A combination of 2D- and 3D-reconstruction analysis showed no clear signs of lead migration, whereas 2D-CT analysis was consistent with migration in 1 patient. Table 3: Number of targeted leads, mean lead age, preprocedural CT findings and extraction methods illustrated for each patient Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser a CT files of TLE cases in which we had to use mechanical tools were evaluated for calcifications around the leads. b Due to bad quality, we were not able to perform 2D and 3D CT analysis in patient number 8. 2D: two-dimensional; 3D: three-dimensional; CT: computed tomography; TLE: transvenous lead extraction. Table 3: Number of targeted leads, mean lead age, preprocedural CT findings and extraction methods illustrated for each patient Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser Patient Targeted leads Mean age of targeted leads (years) Venous occlusion/stenosis Interlead adhesion Vascular adhesion Perforation Calcificationa Extraction method 1 4 76.5 No Yes No No None Laser + mechanical 2 2 97.5 No Yes No No Laser 3 4 57.3 No Yes No No Laser 4 2 120.0 No No Yes No None Laser + mechanical 5 2 73.5 No Yes No No Laser 6 2 44.5 No Yes No No None Laser + snare 7 2 25.5 No No No No Laser 8 1 62.0 b b b b Laser 9 2 49.0 No Yes Yes No Laser 10 4 128.0 No Yes No No None Laser + mechanical 11 3 129.0 Yes No No No Laser 12 1 125.0 No No No No Laser 13 2 127.0 No No No Yes Laser 14 3 172.3 No Yes No No None Laser + mechanical 15 2 108.0 No Yes Yes No Laser 16 2 228.0 No No No Yes Mechanical 17 2 60.0 No Yes No No Laser 18 2 216.0 No Yes Yes No Yes Laser + mechanical + snare 19 1 55.0 No Yes No No Laser 20 3 104.0 No Yes No No Laser 21 3 80.0 No Yes No No Laser 22 2 95.5 No No Yes No Yes Laser + mechanical 23 4 122.5 No Yes No No None Laser + mechanical 24 2 181.0 No No No No Yes Laser + mechanical + snare 25 1 54.0 No No No Yes Mechanical 26 2 159.0 No Yes Yes No None Laser + mechanical 27 2 178.0 No Yes No Yes Yes Laser + mechanical 28 1 64.0 No No No Yes Laser 29 1 77.0 No No No No Laser 30 3 124.7 No Yes No No Yes Laser + mechanical 31 2 253.5 Yes Yes No No Laser a CT files of TLE cases in which we had to use mechanical tools were evaluated for calcifications around the leads. b Due to bad quality, we were not able to perform 2D and 3D CT analysis in patient number 8. 2D: two-dimensional; 3D: three-dimensional; CT: computed tomography; TLE: transvenous lead extraction. Figure 2: View largeDownload slide Example of a patient with possible myocardial perforation of the right ventricular pacing lead in a three-dimensional reconstructed computed tomography (CT) file (A) and the two-dimensional CT file (B). Figure 2: View largeDownload slide Example of a patient with possible myocardial perforation of the right ventricular pacing lead in a three-dimensional reconstructed computed tomography (CT) file (A) and the two-dimensional CT file (B). Procedural data Mean procedural duration was 123.1 ± 58.0 min. The 80-Hz excimer laser (14- and 16-Fr sheaths) was used in 18 (58.1%) patients, and the Cook Evolution RL (13-Fr sheath) was used in 2 (6.5%) patients. In the remaining 11 patients, TLE was performed using a combination of the excimer laser, powered mechanical tools [Cook Evolution RL (13 Fr) or Spectranetics Tight rail (11 Fr)], and/or femoral snares (Table 4). The additional use of mechanical tools (in addition to the excimer laser) was not related to age (P = 0.832, U-test), gender (P > 0.999, Fisher’s exact test), renal insufficiency (P = 0.248, Fisher’s exact test), total number of implanted leads (P = 0.172, χ2 test) or the existence of interlead adhesions in the Et-CT (P = 0.538, Fisher’s exact test). Table 4: Procedural data and outcomes Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) CI: confidence interval; SD: standard deviation. Table 4: Procedural data and outcomes Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) Patients n = 31 Procedural duration (min), mean ± SD [95% CI] 123.1 ± 58.0 [101.8–144.4] Fluoroscopy duration (s), mean ± SD [95% CI] 1155.8 ± 929.6 [814.8–1496.8] Extraction tools, n (%) [95% CI]  Laser sheath only 18 (58.1) [0.39–0.75]  Mechanical tool only 2 (6.5) [0.01–0.21]  Laser + mechanical tool 9 (29.0) [0.14–0.48]  Laser + femoral snare 1 (3.2) [0.00–0.17]  Laser + mechanical tool +  femoral snare 1 (3.2) [0.00–0.17] Laser treatment time (s), mean ± SD [95% CI] 64.1 ± 62.0 [36.6–91.6] Laser impulses, mean ± SD [95% CI] 5363.7 [3002.1–7725.4] Outcome of extraction, n (%)  Clinical success 31 (100)  Complete procedural success 29 (93.5) CI: confidence interval; SD: standard deviation. Clinical success was achieved in all patients, and complete procedural success was achieved in 29 (93.5%) patients. In 1 of the 2 patients in which procedural success was not achieved, we were unable to stabilize 2 abandoned ICD leads with lead locking devices (LLD™; Spectranectics, Colorado Springs, USA). We did not attempt further extraction manoeuvres because the indication for TLE was an upgrade, which was successfully performed by extracting the newest (active) ICD lead. The other case involved TLE for atrial and ventricular lead dysfunction. After extracting the ICD lead and implanting a new ICD lead, we were unable to implant a new atrial lead from the left side because of aggressive adhesions and totally occluded subclavian–innominate veins. Therefore, we had to implant a new atrial lead from the right side. Two minor complications (1 pocket haematoma and 1 pneumothorax) and 1 major complication occurred after TLE. The major complication was unrelated to TLE as it involved resuscitation for an unknown reason 8 h post-TLE after removing a femoral compression device. No intraprocedural complications were observed. Two deaths unrelated to TLE occurred during the hospital stay due to septic shock in 1 patient and hypoxic encephalopathy after resuscitation in the other patient. DISCUSSION Our data showed that an Et-CT prior to TLE was able to visualize lead alignment (Fig. 3) from the subclavian vein to the heart as well as detect lead abnormalities such as vascular adhesions, interlead adhesions, myocardial perforations, venous occlusions and calcification. These findings have been described to some extent in a case report and in a study by Lewis etal. [12, 13] in 30 patients who received a preprocedural ECG-gated CT. However, while Lewis et al. focused on identifying significant perforations and lead adhesions to central venous structures to assess the risk for complications during TLE, they did not consider the potential role of Et-CT in navigating or planning TLE. Abnormalities seen on Et-CT may not only identify patients at a higher risk for complications during TLE but also help to optimize and refine the intraoperative TLE setting. In high-risk patients with severe interlead adhesions and/or adhesions at the SVC predisposing patients for SVC tears, the use of femoral sheaths and a pigtail catheter in the internal jugular vein should be routinely applied to safely manage a tear with rescue devices. Another option in these high-risk TLE patients is the prophylactic placement of an endovascular occlusion balloon in the vena cava [14]. Due to signs of perforation and adhesion seen on ET-CT, we utilized an endovascular balloon in addition to our routine intraoperative setting as a backup in some patients with very old leads. Therefore, an Et-CT can increase the safety of TLE, especially in patients with infections where TLE is mandatory. In contrast to other groups [13], we did not reject TLE in case of a possible perforation on Et-CT, but we were more vigilant about perioperative pericardial effusion resulting in pericardiocentesis. Figure 3: View largeDownload slide Electrocardiogram-triggered computed tomography prior to transvenous lead extraction after three-dimensional reconstruction using 3mensio Structural Heart™ in a cardiac resynchronization therapy defibrillator patient (A) and a pacemaker-dependent patient showing alignment of the leads within the right ventricle and the coronary sinus (B). Figure 3: View largeDownload slide Electrocardiogram-triggered computed tomography prior to transvenous lead extraction after three-dimensional reconstruction using 3mensio Structural Heart™ in a cardiac resynchronization therapy defibrillator patient (A) and a pacemaker-dependent patient showing alignment of the leads within the right ventricle and the coronary sinus (B). A systemically analysed Et-CT prior to TLE may help in choosing the optimal extraction tool and approach for TLE. Our group [15] and other groups [7, 16] have described promising results of TLE with the 80-Hz excimer laser as the sole extraction tool in patients with significantly shorter lead dwell times than in our present study (50.3 ± 18.4 months vs 109.3 ± 58.7 months). However, the excimer laser is sometimes unsuccessful as an exclusive tool in patients with older leads and calcified interlead or vascular adhesions. In these cases, complete TLE success can only be achieved with the additional use of powered mechanical tools with rotating threaded tip sheaths. Our study is the first to systematically evaluate preprocedural 2D CT files and 3D reconstruction files of an Et-CT using 3mensio Structural Heart for these adhesions and other predefined abnormalities. Identification of strong and severely calcified adhesions between the leads or adjacent to the venous wall before the actual extraction may guide the clinician in planning the optimal strategy and extraction tool for the procedure. This is especially helpful when deciding to switch from one tool to another (from the laser sheath to a mechanical tool). However, identification of calcifications is still the most challenging task of preprocedural analysis as it requires differentiation between chalk and metallic streak artefacts. Due to the lack of an exact definition and classification of interlead adhesions, vascular adhesions and calcifications on Et-CT, further improvement of image analysis using CT raw data and the development of standards are necessary. In our first small series, we were, therefore, unable to detect a relationship between the additional use of mechanical tools and interlead adhesions in patients where the excimer laser as an exclusive tool failed. Large multicentre studies and further refinement of image analysis are now necessary to evaluate whether it is possible to choose the optimal extraction tool depending on the type of interlead and vascular adhesions seen on preprocedural Et-CT. The development of image integration systems for the hybrid operating suite may also allow integration of Et-CTs into fluoroscopy systems as has already been established in electrophysiology labs that integrate CTs and magnetic resonance imaging into mapping systems. Integration of Et-CTs with intraoperatively performed venography, live fluoroscopy and 3D-transoesophageal echocardiography could enable us to perform real-time TLE navigation in the future. As with any X-ray-based imaging modality, there is a concern about radiation exposure. However, given the potential fatal complications of TLE, we believe the benefits of an Et-CT outweigh the risks of the additional radiation exposure in high-risk TLE patients. In low-risk patients with a short lead dwell time, a preprocedural Et-CT is probably not required. Limitations The major limitation of this study is that it is a small, non-randomized, retrospective, single-centre study. The only way to evaluate the potential value of an Et-CT would be a prospective clinical trial comparing procedural data and outcome of patients with an Et-CT prior to TLE with a similar group of patients without an Et-CT. Therefore, a definite statement considering the value of an Et-CT cannot be made based on this preliminary work. Furthermore, only patients deemed to be at high risk received an Et-CT. Due to limited data on risk factors of patients undergoing TLE [17], a standard definition of high-risk TLE patients has not yet been established. Thus, the definition of high risk is centre specific. Additionally, one of the major limitations in radiological analysis was the exact differentiation of true calcifications and interlead adhesions from metallic streak artefacts as well as the classification of the severity of interlead adhesions. Although this limitation may be overcome in future, an Et-CT is unable to distinguish leads that are adjacent to the SVC lateral wall from the ones that are embedded in the wall. Other intraoperative imaging techniques such as 3D transoesophageal echocardiography offer real-time, dynamic monitoring and may provide such information. CONCLUSION A preprocedural Et-CT followed by 2D and 3D reconstruction using a specialized software may offer the potential to identify lead abnormalities that may foreshadow complications during TLE. Integrating a special Et-CT into the preprocedural workflow of patients undergoing TLE can help both to reduce complications by optimizing the intraoperative setting and to achieve complete procedural success by choosing the optimal extraction tool for each patient. Large, multicentre studies are warranted to prospectively evaluate whether an Et-CT has an impact on outcome and complications of TLE. Conflict of interest: Samer Hakmi is a consultant/training proctor of Spectranetics Corp. All other authors declared no conflict of interest. REFERENCES 1 Buiten MS , van der Heijden AC , Schalij MJ , van Erven L. How adequate are the current methods of lead extraction? A review of the efficiency and safety of transvenous lead extraction methods . Europace 2015 ; 17 : 689 – 700 . Google Scholar CrossRef Search ADS PubMed 2 Greenspon AJ , Patel JD , Lau E , Ochoa JA , Frisch DR , Ho RT et al. Trends in permanent pacemaker implantation in the United States from 1993 to 2009: increasing complexity of patients and procedures . J Am Coll Cardiol 2012 ; 60 : 1540 – 5 . Google Scholar CrossRef Search ADS PubMed 3 Kurtz SM , Ochoa JA , Lau E , Shkolnikov Y , Pavri BB , Frisch D et al. Implantation trends and patient profiles for pacemakers and implantable cardioverter defibrillators in the United States: 1993-2006 . Pacing Clin Electrophysiol 2010 ; 33 : 705 – 11 . Google Scholar CrossRef Search ADS PubMed 4 Maytin M , Jones SO , Epstein LM. Long-term mortality after transvenous lead extraction . Circ Arrhythm Electrophysiol 2012 ; 5 : 252 – 7 . Google Scholar CrossRef Search ADS PubMed 5 Wilkoff BL , Byrd CL , Love CJ , Hayes DL , Sellers TD , Schaerf R et al. Pacemaker lead extraction with the laser sheath: results of the pacing lead extraction with the excimer sheath (PLEXES) trial . J Am Coll Cardiol 1999 ; 33 : 1671 – 6 . Google Scholar CrossRef Search ADS PubMed 6 Wilkoff BL , Love CJ , Byrd CL , Bongiorni MG , Carrillo RG , Crossley GH 3rd et al. Transvenous lead extraction: Heart Rhythm Society expert consensus on facilities, training, indications, and patient management: this document was endorsed by the American Heart Association (AHA) . Heart Rhythm 2009 ; 6 : 1085 – 104 . Google Scholar CrossRef Search ADS PubMed 7 Wazni O , Epstein LM , Carrillo RG , Love C , Adler SW , Riggio DW et al. Lead extraction in the contemporary setting: the LExICon study: an observational retrospective study of consecutive laser lead extractions . J Am Coll Cardiol 2010 ; 55 : 579 – 86 . Google Scholar CrossRef Search ADS PubMed 8 Maisel WH , Hauser RG , Hammill SC , Hauser RG , Ellenbogen KA , Epstein AE et al. Recommendations from the Heart Rhythm Society task force on lead performance policies and guidelines: developed in collaboration with the American College of Cardiology (ACC) and the American Heart Association (AHA) . Heart Rhythm 2009 ; 6 : 869 – 85 . Google Scholar CrossRef Search ADS PubMed 9 Wilkoff BL , Kennergren C , Love CJ , Kutalek SP , Epstein LM , Carrillo R. Bridge to surgery: best practice protocol derived from early clinical experience with the Bridge Occlusion Balloon. Federated Agreement from the Eleventh Annual Lead Management Symposium . Heart Rhythm 2017 ; 14 : 1574 – 8 . Google Scholar CrossRef Search ADS PubMed 10 Hakmi S , Pecha S , Sill B , Reiter B , Willems S , Aydin MA et al. Initial experience of pacemaker and implantable cardioverter defibrillator lead extraction with the new GlideLight 80 Hz laser sheaths . Interact CardioVasc Thorac Surg 2014 ; 18 : 56 – 60 . Google Scholar CrossRef Search ADS PubMed 11 Balabanoff C , Gaffney CE , Ghersin E , Okamoto Y , Carrillo R , Fishman JE. Radiographic and electrocardiography-gated noncontrast cardiac CT assessment of lead perforation: modality comparison and interobserver agreement . J Cardiovasc Comput Tomogr 2014 ; 8 : 384 – 90 . Google Scholar CrossRef Search ADS PubMed 12 Sidiqi I , Ghalayini W , Zughaib T , Machado C. Use of computed tomography as a screening modality before lead extraction for patients affected by failure of the recalled riata leads: a case report . J Innovations Card Rhythm Manag 2013 ; 4 : 1325 – 7 . 13 Lewis RK , Pokorney SD , Greenfield RA , Hranitzky PM , Hegland DD , Schroder JN et al. Preprocedural ECG-gated computed tomography for prevention of complications during lead extraction . Pacing Clin Electrophysiol 2014 ; 37 : 1297 – 305 . Google Scholar CrossRef Search ADS PubMed 14 Tsang DC , Azarrafiy R , Pecha S , Reichenspurner H , Carrillo RG , Hakmi S. Long-term outcomes of prophylactic placement of an endovascular balloon in the vena cava for high-risk transvenous lead extractions . Heart Rhythm 2017 ; 14 : 1833 – 8 . Google Scholar CrossRef Search ADS PubMed 15 Pecha S , Yildirim Y , Gosau N , Aydin MA , Willems S , Treede H et al. Laser lead extraction allows for safe and effective removal of single- and dual-coil implantable cardioverter defibrillator leads: a single-centre experience over 12 years . Interact CardioVasc Thorac Surg 2017 ; 24 : 77 – 81 . Google Scholar CrossRef Search ADS PubMed 16 Tanawuttiwat T , Gallego D , Carrillo RG. Lead extraction experience with high frequency excimer laser . Pacing Clin Electrophysiol 2014 ; 37 : 1120 – 8 . Google Scholar CrossRef Search ADS PubMed 17 Fu HX , Huang XM , Zhong LI , Osborn MJ , Asirvatham SJ , Espinosa RE et al. Outcomes and complications of lead removal: can we establish a risk stratification schema for a collaborative and effective approach? Pacing Clin Electrophysiol 2015 ; 38 : 1439 – 47 . Google Scholar CrossRef Search ADS PubMed © The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices)

Journal

European Journal of Cardio-Thoracic SurgeryOxford University Press

Published: Mar 30, 2018

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off