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Novel fast-track recovery protocol for alternative access transcatheter aortic valve replacement: application to non-femoral approaches

Novel fast-track recovery protocol for alternative access transcatheter aortic valve replacement:... Abstract OBJECTIVES Although the transfemoral approach for transcatheter aortic valve replacement is the preferred choice, alternative access remains indicated for inadequate iliofemoral vessels. We report the successful implementation of a novel fast-track (FT) protocol for patients undergoing alternative access transcatheter aortic valve replacement compared with conventional controls. METHODS Between September 2014 and January 2017, 31 and 23 patients underwent alternative access transcatheter aortic valve replacement under FT and pre-fast-track (p-FT) protocols, respectively. Comparisons of outcomes (in terms of mortality, complications, readmissions and resource utilization) were made before and after the implantation of the FT protocol in September 2015. RESULTS Overall, mean age was 78.7 years in FT and 79.6 years in p-FT patients (P = 0.71). There were no significant differences in procedural (3.2% vs 13.0%, P = 0.301) or 90-day mortality (3.2% vs 17.4%, P = 0.151) between the FT and p-FT groups, respectively. Compared with p-FT patients, FT patients had significantly shorter intensive care unit stays (12 h vs 27 h, P = 0.006) and a trend towards more discharges within 3 days (41.9% vs 17.4%, P = 0.081). Resource utilization analyses projected a 56% and 17% reduction in the mean intensive care unit time (hours) per 100 patients and the total length of stay (days) per 100 patients, respectively, with respect to the FT approach. CONCLUSIONS This pilot study demonstrates the feasibility and safety of the novel FT protocol for alternative access transcatheter aortic valve replacement, resulting in shorter intensive care unit stays, without increasing procedural complications or readmissions. With the expected increase in transcatheter aortic valve replacement utilization, FT protocols should be integrated with a multidisciplinary heart team approach to enhance patient recovery and optimize resource utilization. Cardiovascular diseases/therapy, Transcatheter aortic valve replacement, Heart team, Resource utilization INTRODUCTION Within the last decade, transcatheter aortic valve replacement (TAVR) has emerged as an established and viable treatment option for patients with severe aortic stenosis who are deemed to be inoperable, at high risk or with an intermediate risk for surgical aortic valve replacement [1–3]. Over 250 000 TAVR procedures have been performed worldwide since 2002 [1, 4, 5], with recent registry data indicating an 87% utilization rate of the transfemoral (TF) approach [6]. This trend could be explained by the increasing feasibility of the TF approach in the light of contemporary technological advances in valve technologies, including a smaller sheath size of newer generation valves [6–8]. The recent results of the Placement of Aortic Transcatheter Valve (PARTNER) 2 trial were also pivotal and showed that TF-TAVR resulted in lower mortality and stroke rates than conventional surgery, whereas transthoracic TAVR (non-femoral) did not provide better results [1]. However, the TF approach is often precluded in patients with small, tortuous or calcified iliofemoral vessels, for which alternative access sites are indicated. These access sites include transapical (TA), transaortic (TAo), trans-subclavian (SC), transcarotid and transcaval approaches [9–11]. Although enhanced operator experience and technical advancement of TAVR devices have improved the overall outcomes of TAVR, with decreased vascular complications and procedural mortality [7, 12], alternative access is still associated with increased cost, resource utilization, length of stay (LOS) and procedural time compared with the conventional TF approach [13]. The movement towards ‘minimalist approaches (MAs)’ and ‘fast-track (FT) protocols’ for patients undergoing TF-TAVR has gained appreciable momentum in recent years, partly due to concerns over increased resource utilization in spite of the heart team approach [14, 15]. Some of these protocols include avoidance of general anaesthesia (GA), use of low-dose or short-acting opioids and earlier extubation and ambulation. Moreover, the MA and FT protocols for TF-TAVR have been shown to provide comparable outcomes to the conventional or ‘standard protocols’ while significantly cutting the overall costs, resource utilization and duration of hospitalization, all being critically important considerations in modern medicine, especially in the context of quality improvement and hospital reimbursements [16, 17]. Although the non-femoral approaches have been associated with worse outcomes and more resource utilization than the TF approach [13, 18], the advent of smaller delivery systems has allowed the SC approach to gain more popularity, with outcomes comparable with that of the TF approach [8, 19–21]. It provides a feasible alternative when TF access is not possible, eliminates the need for opening the chest cavity and, in most cases, is only limited by the diameter of the SC artery. Furthermore, it may be amenable to anaesthetic alternatives for GA. We implemented an FT protocol for TF-TAVR in October 2014 and recently adapted the programme for alternative access transcatheter aortic valve replacement (AA-TAVR) in September 2015 with our heart team approach. We sought to demonstrate the success of our pilot study and highlight the safety, efficacy, cost and resource utilization, including the outcomes of AA-TAVR before and after the implementation of our novel FT protocol. MATERIALS AND METHODS Study population Following approval from our institutional review board, we reviewed all cases of AA-TAVR at our centre between September 2014 and January 2017. A total of 54 patients were identified, including 31 FT and 23 pre-fast-track (p-FT) patients. Fast-track protocol Our FT protocol for AA-TAVR was initiated in September 2015. Patient selection algorithm is summarized in Fig. 1. The protocol consists of the following: For TAVR, when the patient has inadequate iliofemoral vessels, computed tomography scan is used to reconstruct bilateral subclavian arteries. If the arteries are larger than 5 mm, the SC approach is chosen. We prefer to utilize the left SC as our first option. However, if the left SC is inadequate, we use the right SC as our second option. If bilateral SC arteries are inadequate, we choose between TAo and TA. Transcarotid and transcaval are not used because of our lack of experience with both approaches. Figure 1: View largeDownload slide Patient selection criteria for the FT protocol. FT: fast-track; TAVR: transcatheter aortic valve replacement. Figure 1: View largeDownload slide Patient selection criteria for the FT protocol. FT: fast-track; TAVR: transcatheter aortic valve replacement. Before the procedure, the regional anaesthesia team performs ultrasound-guided proximal intercostal nerve blocks at the surgical site and at the appropriate levels required for the TAo and TA approaches, and perineural catheters are placed for continuous bupivacaine infusion at a rate of 6–10 ml/h for post-procedural analgesia. The perioperative pain service manages the perineural infusions, and the catheters are removed on post-procedural Days 1 or 2, after the chest tubes are removed. One of the immediate post-procedural goals is to extubate the patients in the hybrid operating room soon after skin closure. This is made possible with customized anaesthetic drug selection and timing and is facilitated by regional analgesia (nerve blocks), as planned and conducted by a team of subspecialty-trained anaesthesiologists. Restrictive fluid therapy is administered by the intensive care unit (ICU) team, limiting post-procedural fluid boluses and/or vasopressor infusions, in direct communication and collaboration with the surgical team. Adequate training is also given to the nursing staff in the ICU and step-down units. After taking the patients to the ICU, the urinary catheter and arterial line are quickly removed after 2 h, and the patients are actively mobilized out of bed within 4 h. ICU discharge goal is 6 h, if all the discharge criteria are met. The ICU discharge criteria include intact neurological function, stable respiratory status, stable haemodynamics and no bleeding from the access sites. A multidisciplinary ‘heart team’, including cardiologists, cardiac surgeons, intensivists and anaesthesiologists, collaborates closely to achieve a safe FT recovery for these patients. For the SC TAVRs, an alternative anaesthetic approach has been designed by the regional anaesthesia team to avoid GA when possible. The goal is to provide surgical anaesthesia of the upper chest wall, ipsilateral axilla and upper extremity over 3–4 h, with arm immobility while sparing the respiratory muscles. This is achieved by a combination of proximal brachial plexus blocks (usually via a retroclavicular approach), pectoral muscles I/II blocks and blocks of the supraclavicular nerves and the intercostobrachial nerve. Data collection and outcomes Patient characteristics, periprocedural data and in-hospital outcomes were recorded electronically at the time of presentation. Data were extracted from our electronic medical records, and variables were defined and coded according to the Society of Thoracic Surgery (STS)/American College of Cardiology (ACC) Transcatheter Valve Therapy (TVT) registry v2.0 specifications unless otherwise noted. Procedural mortality was defined as any death occurring in-house during the index admission or within 30 days of the procedure, if discharged. These inpatient data were then merged with our hospital cost data software system using a combination of the medical record number and the admission date ±1 day for deterministic linkage. Our hospital uses a cost accounting system from Allscripts called EPSi that allocates all hospital patient costs by departments and services. EPSi is a clinical and financial data repository, a management planning, analysis and cost-control tool that includes data on the hospital costs and resource use of all hospitalizations. Outpatient costs and professional billing costs (e.g. physician services) were excluded, but some physician services were included if they were provided for under the hospital’s billed services (e.g. bundled payments for services that include physician care). Primary outcomes of interest were procedural (i.e. in-hospital) and 90-day mortality, ICU stay and hospital LOS. Secondary outcomes of interest included permanent stroke and pacemaker implantation, residual aortic insufficiency, atrial fibrillation, new dialysis dependence, ICU and 30-day readmission rates and direct and total hospitalization cost. Resource utilization was calculated by projecting percent reductions in the mean ICU time in hours, per 100 patients, and the total hospital LOS in days, per 100 patients. Statistical analysis To compare the FT group with the pFT group, normally distributed continuous variables were expressed as mean with standard deviation and compared using the Student’s t-test. Non-normally distributed variables were expressed as median and interquartile range and compared using the Mann–Whitney U-tests. Categorical variables were presented as number and percentages and compared using the χ2 test or the Fisher’s exact test (for small cell sizes, i.e. for expected values <5). All analyses were done using IBM SPSS Statistics version 22.0 (IBM Corporation, Armonk, NY, USA), and a P-value ≤0.05 was the criterion for significance. RESULTS Preprocedural characteristics Baselines characteristics of FT and p-FT patients are listed in Table 1. There were 31 FT and 23 p-FT patients in this pilot study, with a mean age of 78.7 ± 8.7 and 79.6 ± 7.6 years (P = 0.708), respectively. Most comorbidities, including diabetes mellitus, hypertension, atrial fibrillation and previous stroke or myocardial infarction, were similar between the 2 groups. Compared with the p-FT group, FT patients tended to have a lower burden of peripheral arterial disease, chronic obstructive pulmonary disease and New York Heart Association Class III/IV. However, the mean STS Predicted Risk of Mortality (STS-PROM) score was similar in both groups (6.60 ± 3.40% in FT vs 7.98 ± 3.80% in p-FT, P = 0.178). Similarly, baseline median ejection fraction (P = 0.499), mean peak aortic jet velocity (P = 0.309) and mean aortic valve gradients (P = 0.931), based on the preoperative echocardiography, were also similar between the 2 groups. Notably, there were 2 and 4 inoperable cases (or patients with STS-PROM >12%) in the FT and p-FT groups, respectively. Table 1: Baseline patient and echocardiographic characteristics in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). AV: aortic valve; AVR: aortic valve replacement; COPD: chronic obstructive pulmonary disease; IQR: interquartile range; MI: myocardial infarction; NYHA: New York Heart Association; PROM: predicted risk of mortality; SD: standard deviation; STS: Society of Thoracic Surgeons; Vmax: peak aortic jet velocity. Table 1: Baseline patient and echocardiographic characteristics in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). AV: aortic valve; AVR: aortic valve replacement; COPD: chronic obstructive pulmonary disease; IQR: interquartile range; MI: myocardial infarction; NYHA: New York Heart Association; PROM: predicted risk of mortality; SD: standard deviation; STS: Society of Thoracic Surgeons; Vmax: peak aortic jet velocity. Procedural and postoperative outcomes Compared with pre-FT patients, FT patients had a significantly higher proportion of SC access (77.4% vs 21.7%) but a lower proportion of TAo access (22.6% vs 60.9%) in the TAVR performed (P < 0.001). Similarly, the valve types were significantly different between the 2 groups (P < 0.001). There was also no difference in the median procedural lengths between the 2 groups (P = 0.298). GA was used for all except 1 patient in the FT group. Moreover, only 1 FT patient did not complete the protocol because of multiple comorbidities, including severe liver cirrhosis and a decubitus ulcer, which required an extended stay (Table 2). Table 2: Procedural and postoperative outcomes of patients in the pre-fast-track and fast-track protocols Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). a One patient in the fast-track group underwent the procedure awake under regional anaesthesia and sedation alone. CPB: cardiopulmonary bypass; ICU: intensive care unit; IQR: interquartile range; LOS: length of stay; SD: standard deviation; TAVR: transcatheter aortic valve replacement. Table 2: Procedural and postoperative outcomes of patients in the pre-fast-track and fast-track protocols Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). a One patient in the fast-track group underwent the procedure awake under regional anaesthesia and sedation alone. CPB: cardiopulmonary bypass; ICU: intensive care unit; IQR: interquartile range; LOS: length of stay; SD: standard deviation; TAVR: transcatheter aortic valve replacement. There were no significant differences in procedural mortality (3.2% vs 13.0%, P = 0.301) or 90-day mortality (3.2% vs 17.4%, P = 0.151) between the FT and the p-FT groups, respectively. Similarly, there were no significant differences in procedural complications (such as new-onset atrial fibrillation and permanent pacemaker) or valve performance between the FT and the p-FT groups. Compared with p-FT patients, FT patients had significantly shorter median ICU stays (12 h vs 27 h, P = 0.006) and a trend towards more discharges within 3 days (41.9% vs 17.4%, P = 0.081). Importantly, there were no ICU readmissions, post-procedural strokes, new-onset dialysis dependence or residual moderate or severe aortic insufficiency in either group. Although the 30-day readmission rate was 6.5% for the FT group and 13.0% for the p-FT group, it did not reach statistical significance (P = 0.377). Cost and resource utilization Resource utilization analyses projected a 56% and 17% reduction in the mean ICU time (h) per 100 patients and total LOS (days) per 100 patients, respectively. The overall median direct cost of hospitalization, as measured by the overall relative median cost, was 3% lower (P = 0.87), while the median total cost of hospitalization was reduced by 2% (P = 0.690) after implementation of the FT protocol, mostly due to shorter ICU stays and total LOS, as highlighted in Table 3. Table 3: Cost and resource utilization among patients in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Values presented as median (IQR). a y represents the median cost per TIA patient in the preintervention phase. Outpatient costs and professional billing costs (e.g. physician services) were excluded, but some physician services were included if they were provided for under the hospital’s billed services (e.g. bundled payments for services that include physician care). ICU: intensive care unit; IQR: interquartile range; TIA: transient ischaemic attack. Table 3: Cost and resource utilization among patients in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Values presented as median (IQR). a y represents the median cost per TIA patient in the preintervention phase. Outpatient costs and professional billing costs (e.g. physician services) were excluded, but some physician services were included if they were provided for under the hospital’s billed services (e.g. bundled payments for services that include physician care). ICU: intensive care unit; IQR: interquartile range; TIA: transient ischaemic attack. DISCUSSION To our knowledge, limited data exist on the FT protocols for AA-TAVR in the current era [16]. Importantly, our pilot study had several noteworthy findings. First, it demonstrated the safety and feasibility of our novel FT protocol in patients undergoing AA-TAVR. Secondly, clinically observed procedural mortality had decreased to about one-fourth, while 90-day mortality was almost a fifth of that prior to FT protocol implementation, although not statistically significant. Remarkably, there were no cases of post-procedural strokes, new-onset dialysis dependence or ICU readmissions. From a resource utilization standpoint, we demonstrated a substantial reduction in the overall ICU time and hospital LOS among FT patients, with a trend towards earlier hospital discharge—which translated into an overall lower median total and direct cost of hospitalization—without increasing the post-procedural complications or readmissions. TAVR has emerged as a viable alternative for inoperable, high or intermediate STS-risk patients with aortic stenosis [1, 5, 22]. Traditionally, the main access site has been via the femoral artery, because it allows for total percutaneous access and has been shown to have superior outcomes to the non-TF approaches [23, 24]. Unfortunately, certain characteristics, such as peripheral vascular disease and inadequate vessel calibre, still preclude the TF approach in selected patients, creating the need for alternative approaches such as TA, TAo, SC, transcarotid and transcaval [9]. Data from a large UK registry directly compared the TF approach with all the non-femoral approaches [8]. The TAo and TA approaches were found to have significantly worse short- and long-term outcomes. However, the SC and TF approaches had comparable outcomes. A recent study further validated the safety and feasibility of the SC approach in 100 consecutive patients with promising results [25]. A possible explanation as to why the SC approach offers better results than the other non-femoral approaches could be because of its peripheral and less invasive nature, without the need for extensive cut-down or entering the chest cavity. Historically, FT protocols for cardiac surgery were first introduced in the early 90s with the advent of early ventilator weaning and ambulation [26]. They have been shown to hasten the recovery of patients and improve cardiac performance as well as overall progression to a fully functional status [27]. The traditional school of thought holds that monitoring patients for postoperative complications deems conventional (non-FT) protocols indispensable, for a more stable and controlled environment [16]. Furthermore, this specific patient population undergoing TAVR tends to be frailer than other cardiac patients, warranting extra caution throughout the periprocedural period and creating reluctance towards early discharge. Nonetheless, cost and resource utilization arise as important factors to be considered [28]. Keeping these factors in mind, our institution started an FT protocol for TF-TAVR patients in October 2014 and adapted a similar protocol for AA-TAVR patients in September 2015. In our pilot study, FT and p-FT patients had comparable outcomes. Clinically, procedural and 90-day mortality were lower in the FT group, although limited by the small sample size and fewer number of events. Although ICU readmission rates have been reported to be between 2% and 5% in low-risk cardiac surgery patients [16], none of the patients in our series required an ICU readmission, despite their high-risk profile. Moreover, patients in the FT group had significantly shorter ICU stays and a trend towards more discharges within 3 days. This translated to reduced cost and resource utilization and was in line with similar studies except in TF-TAVR [14–17]. For instance, the ‘Vancouver TAVR clinical pathway’ proved successful for proper risk stratification and LOS optimization in 144 consecutive patients undergoing TF-TAVR [15, 29]. Similarly, Babaliaros et al. [14] championed the concept with a comparison between their MA and the standard approach in 142 patients undergoing TF-TAVR. While both approaches had similar safety and efficacy outcomes, the MA was associated with significant reduction of costs ($45 485 vs $55 377), ICU stays (22 h vs 28 h) and hospital LOS (3 days vs 5 days), all P < 0.001. Our pilot study highlights the pivotal role of a multidisciplinary heart team in determining the most appropriate mode of TAVR access, taking into account the operator’s experience and centre’s facilities. Similarly, close interaction among the members of the heart team is equally important. In our experience, several patients were discharged on the post-procedural Day 1 with the SC approach, which did not occur with the other approaches. Moreover, we do not routinely perform the transcarotid or transcaval approach, given our lack of experience with these approaches. Thus, as a team, we adopted the SC-first approach within our novel FT protocol. Taking the MA one step further, we also designed a uniquely tailored regional anaesthesia approach to avoid GA whenever possible, speed up recovery and improve outcomes further. Although we only included our first awake SC-TAVR patient in this study, we have since instituted this as our default alternative, with encouraging early results. Limitations Despite its strengths, our study is subject to all the limitations inherent to a single-centre, retrospective study. Our pilot study is the first of its kind to demonstrate the utility and safety of the FT protocol in AA-TAVR, despite the small sample size which may not be generalizable to other populations. Only 10% of TAVRs are performed via alternative access, and with a case volume of 300 per year, our academic centre only sees about 30 patients with alternative access. It could also be feasible that the improved outcomes may be associated with other policy changes in our TAVR programme or because of the transition from a primarily descending aortic approach to a default strategy of the SC approach (i.e. selection bias, given our FT protocol) rather than with the implementation of the protocol. This may require further validation studies. Moreover, because of the smaller devices available, the FT group may have included fewer significant peripheral vascular disease patients. Notably, there were also significantly fewer patients with New York Heart Association Class III/IV in the FT groups. This imbalance may have influenced the results in favour of the FT group because we did not have enough power to address these using multivariable methods. Our univariate analysis showed that peripheral artery disease was marginally associated with overall mortality, but there was no association with New York Heart Association Class III/IV and our outcomes (P = 0.112). Concerning patient care, we initiated our TF FT programme in November 2014, but our patient management did not change until the incorporation of alternative access FT. Overall, the initial success of our novel FT protocol is worth considering on a wider scale and, to some extent, provides a framework for future studies that examine the feasibility and cost-effectiveness of the FT protocols, especially in high-risk patients undergoing AA-TAVR in the current era. CONCLUSION This small observational study demonstrated the safety of the novel FT protocol for AA-TAVR, resulting in shorter ICU stays and earlier hospital discharge, without increasing procedural complications or readmissions. With the expected increase in TAVR utilization in the coming years, the FT protocols should be widely considered and integrated closely with the multidisciplinary heart team approach to enhance patient recovery and optimize resource utilization. ACKNOWLEDGEMENTS We thank Sarah M. Dougherty for her help with cost analysis. Conflict of interest: none declared. REFERENCES 1 Leon MB , Smith CR , Mack MJ , Makkar RR , Svensson LG , Kodali SK et al. . Transcatheter or surgical aortic-valve replacement in intermediate-risk patients . N Engl J Med 2016 ; 374 : 1609 – 20 . Google Scholar CrossRef Search ADS PubMed 2 Smith CR , Leon MB , Mack MJ , Miller DC , Moses JW , Svensson LG et al. . Transcatheter versus surgical aortic-valve replacement in high-risk patients . N Engl J Med 2011 ; 364 : 2187 – 98 . Google Scholar CrossRef Search ADS PubMed 3 Makkar RR , Fontana GP , Jilaihawi H , Kapadia S , Pichard AD , Douglas PS et al. . 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Fast-track cardiac surgery: application in an Australian setting . Asian Cardiovasc Thorac Ann 2007 ; 15 : 139 – 43 . Google Scholar CrossRef Search ADS PubMed 28 Haanschoten MC , van Straten AH , ter Woorst JF , Stepaniak PS , van der Meer AD , van Zundert AA et al. . Fast-track practice in cardiac surgery: results and predictors of outcome . Interact CardioVasc Thorac Surg 2012 ; 15 : 989 – 94 . Google Scholar CrossRef Search ADS PubMed 29 Lauck SB , Wood DA , Baumbusch J , Kwon JY , Stub D , Achtem L et al. . Vancouver transcatheter aortic valve replacement clinical pathway: minimalist approach, standardized care, and discharge criteria to reduce length of stay . Circ Cardiovasc Qual Outcomes 2016 ; 9 : 312 – 21 . 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 Interactive CardioVascular and Thoracic Surgery Oxford University Press

Novel fast-track recovery protocol for alternative access transcatheter aortic valve replacement: application to non-femoral approaches

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Oxford University Press
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© The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
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1569-9293
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1569-9285
DOI
10.1093/icvts/ivx409
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Abstract

Abstract OBJECTIVES Although the transfemoral approach for transcatheter aortic valve replacement is the preferred choice, alternative access remains indicated for inadequate iliofemoral vessels. We report the successful implementation of a novel fast-track (FT) protocol for patients undergoing alternative access transcatheter aortic valve replacement compared with conventional controls. METHODS Between September 2014 and January 2017, 31 and 23 patients underwent alternative access transcatheter aortic valve replacement under FT and pre-fast-track (p-FT) protocols, respectively. Comparisons of outcomes (in terms of mortality, complications, readmissions and resource utilization) were made before and after the implantation of the FT protocol in September 2015. RESULTS Overall, mean age was 78.7 years in FT and 79.6 years in p-FT patients (P = 0.71). There were no significant differences in procedural (3.2% vs 13.0%, P = 0.301) or 90-day mortality (3.2% vs 17.4%, P = 0.151) between the FT and p-FT groups, respectively. Compared with p-FT patients, FT patients had significantly shorter intensive care unit stays (12 h vs 27 h, P = 0.006) and a trend towards more discharges within 3 days (41.9% vs 17.4%, P = 0.081). Resource utilization analyses projected a 56% and 17% reduction in the mean intensive care unit time (hours) per 100 patients and the total length of stay (days) per 100 patients, respectively, with respect to the FT approach. CONCLUSIONS This pilot study demonstrates the feasibility and safety of the novel FT protocol for alternative access transcatheter aortic valve replacement, resulting in shorter intensive care unit stays, without increasing procedural complications or readmissions. With the expected increase in transcatheter aortic valve replacement utilization, FT protocols should be integrated with a multidisciplinary heart team approach to enhance patient recovery and optimize resource utilization. Cardiovascular diseases/therapy, Transcatheter aortic valve replacement, Heart team, Resource utilization INTRODUCTION Within the last decade, transcatheter aortic valve replacement (TAVR) has emerged as an established and viable treatment option for patients with severe aortic stenosis who are deemed to be inoperable, at high risk or with an intermediate risk for surgical aortic valve replacement [1–3]. Over 250 000 TAVR procedures have been performed worldwide since 2002 [1, 4, 5], with recent registry data indicating an 87% utilization rate of the transfemoral (TF) approach [6]. This trend could be explained by the increasing feasibility of the TF approach in the light of contemporary technological advances in valve technologies, including a smaller sheath size of newer generation valves [6–8]. The recent results of the Placement of Aortic Transcatheter Valve (PARTNER) 2 trial were also pivotal and showed that TF-TAVR resulted in lower mortality and stroke rates than conventional surgery, whereas transthoracic TAVR (non-femoral) did not provide better results [1]. However, the TF approach is often precluded in patients with small, tortuous or calcified iliofemoral vessels, for which alternative access sites are indicated. These access sites include transapical (TA), transaortic (TAo), trans-subclavian (SC), transcarotid and transcaval approaches [9–11]. Although enhanced operator experience and technical advancement of TAVR devices have improved the overall outcomes of TAVR, with decreased vascular complications and procedural mortality [7, 12], alternative access is still associated with increased cost, resource utilization, length of stay (LOS) and procedural time compared with the conventional TF approach [13]. The movement towards ‘minimalist approaches (MAs)’ and ‘fast-track (FT) protocols’ for patients undergoing TF-TAVR has gained appreciable momentum in recent years, partly due to concerns over increased resource utilization in spite of the heart team approach [14, 15]. Some of these protocols include avoidance of general anaesthesia (GA), use of low-dose or short-acting opioids and earlier extubation and ambulation. Moreover, the MA and FT protocols for TF-TAVR have been shown to provide comparable outcomes to the conventional or ‘standard protocols’ while significantly cutting the overall costs, resource utilization and duration of hospitalization, all being critically important considerations in modern medicine, especially in the context of quality improvement and hospital reimbursements [16, 17]. Although the non-femoral approaches have been associated with worse outcomes and more resource utilization than the TF approach [13, 18], the advent of smaller delivery systems has allowed the SC approach to gain more popularity, with outcomes comparable with that of the TF approach [8, 19–21]. It provides a feasible alternative when TF access is not possible, eliminates the need for opening the chest cavity and, in most cases, is only limited by the diameter of the SC artery. Furthermore, it may be amenable to anaesthetic alternatives for GA. We implemented an FT protocol for TF-TAVR in October 2014 and recently adapted the programme for alternative access transcatheter aortic valve replacement (AA-TAVR) in September 2015 with our heart team approach. We sought to demonstrate the success of our pilot study and highlight the safety, efficacy, cost and resource utilization, including the outcomes of AA-TAVR before and after the implementation of our novel FT protocol. MATERIALS AND METHODS Study population Following approval from our institutional review board, we reviewed all cases of AA-TAVR at our centre between September 2014 and January 2017. A total of 54 patients were identified, including 31 FT and 23 pre-fast-track (p-FT) patients. Fast-track protocol Our FT protocol for AA-TAVR was initiated in September 2015. Patient selection algorithm is summarized in Fig. 1. The protocol consists of the following: For TAVR, when the patient has inadequate iliofemoral vessels, computed tomography scan is used to reconstruct bilateral subclavian arteries. If the arteries are larger than 5 mm, the SC approach is chosen. We prefer to utilize the left SC as our first option. However, if the left SC is inadequate, we use the right SC as our second option. If bilateral SC arteries are inadequate, we choose between TAo and TA. Transcarotid and transcaval are not used because of our lack of experience with both approaches. Figure 1: View largeDownload slide Patient selection criteria for the FT protocol. FT: fast-track; TAVR: transcatheter aortic valve replacement. Figure 1: View largeDownload slide Patient selection criteria for the FT protocol. FT: fast-track; TAVR: transcatheter aortic valve replacement. Before the procedure, the regional anaesthesia team performs ultrasound-guided proximal intercostal nerve blocks at the surgical site and at the appropriate levels required for the TAo and TA approaches, and perineural catheters are placed for continuous bupivacaine infusion at a rate of 6–10 ml/h for post-procedural analgesia. The perioperative pain service manages the perineural infusions, and the catheters are removed on post-procedural Days 1 or 2, after the chest tubes are removed. One of the immediate post-procedural goals is to extubate the patients in the hybrid operating room soon after skin closure. This is made possible with customized anaesthetic drug selection and timing and is facilitated by regional analgesia (nerve blocks), as planned and conducted by a team of subspecialty-trained anaesthesiologists. Restrictive fluid therapy is administered by the intensive care unit (ICU) team, limiting post-procedural fluid boluses and/or vasopressor infusions, in direct communication and collaboration with the surgical team. Adequate training is also given to the nursing staff in the ICU and step-down units. After taking the patients to the ICU, the urinary catheter and arterial line are quickly removed after 2 h, and the patients are actively mobilized out of bed within 4 h. ICU discharge goal is 6 h, if all the discharge criteria are met. The ICU discharge criteria include intact neurological function, stable respiratory status, stable haemodynamics and no bleeding from the access sites. A multidisciplinary ‘heart team’, including cardiologists, cardiac surgeons, intensivists and anaesthesiologists, collaborates closely to achieve a safe FT recovery for these patients. For the SC TAVRs, an alternative anaesthetic approach has been designed by the regional anaesthesia team to avoid GA when possible. The goal is to provide surgical anaesthesia of the upper chest wall, ipsilateral axilla and upper extremity over 3–4 h, with arm immobility while sparing the respiratory muscles. This is achieved by a combination of proximal brachial plexus blocks (usually via a retroclavicular approach), pectoral muscles I/II blocks and blocks of the supraclavicular nerves and the intercostobrachial nerve. Data collection and outcomes Patient characteristics, periprocedural data and in-hospital outcomes were recorded electronically at the time of presentation. Data were extracted from our electronic medical records, and variables were defined and coded according to the Society of Thoracic Surgery (STS)/American College of Cardiology (ACC) Transcatheter Valve Therapy (TVT) registry v2.0 specifications unless otherwise noted. Procedural mortality was defined as any death occurring in-house during the index admission or within 30 days of the procedure, if discharged. These inpatient data were then merged with our hospital cost data software system using a combination of the medical record number and the admission date ±1 day for deterministic linkage. Our hospital uses a cost accounting system from Allscripts called EPSi that allocates all hospital patient costs by departments and services. EPSi is a clinical and financial data repository, a management planning, analysis and cost-control tool that includes data on the hospital costs and resource use of all hospitalizations. Outpatient costs and professional billing costs (e.g. physician services) were excluded, but some physician services were included if they were provided for under the hospital’s billed services (e.g. bundled payments for services that include physician care). Primary outcomes of interest were procedural (i.e. in-hospital) and 90-day mortality, ICU stay and hospital LOS. Secondary outcomes of interest included permanent stroke and pacemaker implantation, residual aortic insufficiency, atrial fibrillation, new dialysis dependence, ICU and 30-day readmission rates and direct and total hospitalization cost. Resource utilization was calculated by projecting percent reductions in the mean ICU time in hours, per 100 patients, and the total hospital LOS in days, per 100 patients. Statistical analysis To compare the FT group with the pFT group, normally distributed continuous variables were expressed as mean with standard deviation and compared using the Student’s t-test. Non-normally distributed variables were expressed as median and interquartile range and compared using the Mann–Whitney U-tests. Categorical variables were presented as number and percentages and compared using the χ2 test or the Fisher’s exact test (for small cell sizes, i.e. for expected values <5). All analyses were done using IBM SPSS Statistics version 22.0 (IBM Corporation, Armonk, NY, USA), and a P-value ≤0.05 was the criterion for significance. RESULTS Preprocedural characteristics Baselines characteristics of FT and p-FT patients are listed in Table 1. There were 31 FT and 23 p-FT patients in this pilot study, with a mean age of 78.7 ± 8.7 and 79.6 ± 7.6 years (P = 0.708), respectively. Most comorbidities, including diabetes mellitus, hypertension, atrial fibrillation and previous stroke or myocardial infarction, were similar between the 2 groups. Compared with the p-FT group, FT patients tended to have a lower burden of peripheral arterial disease, chronic obstructive pulmonary disease and New York Heart Association Class III/IV. However, the mean STS Predicted Risk of Mortality (STS-PROM) score was similar in both groups (6.60 ± 3.40% in FT vs 7.98 ± 3.80% in p-FT, P = 0.178). Similarly, baseline median ejection fraction (P = 0.499), mean peak aortic jet velocity (P = 0.309) and mean aortic valve gradients (P = 0.931), based on the preoperative echocardiography, were also similar between the 2 groups. Notably, there were 2 and 4 inoperable cases (or patients with STS-PROM >12%) in the FT and p-FT groups, respectively. Table 1: Baseline patient and echocardiographic characteristics in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). AV: aortic valve; AVR: aortic valve replacement; COPD: chronic obstructive pulmonary disease; IQR: interquartile range; MI: myocardial infarction; NYHA: New York Heart Association; PROM: predicted risk of mortality; SD: standard deviation; STS: Society of Thoracic Surgeons; Vmax: peak aortic jet velocity. Table 1: Baseline patient and echocardiographic characteristics in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Pre-fast-track (n = 23) Fast-track (n = 31) P-value Patient characteristics  Age (years) 79.6 ± 7.6 78.7 ± 8.7 0.708  Female 11 (47.8) 17 (54.8) 0.784  Hypertension 21 (91.3) 29 (93.5) 1.000  Diabetes mellitus 7 (30.4) 11 (35.5) 0.776  Dialysis dependent 2 (8.7) 2 (6.5) 1.000  Creatinine 1.19 ± 0.64 1.47 ± 1.41 0.374  Peripheral artery disease 16 (69.6) 12 (38.7) 0.031  Previous stroke 3 (13) 5 (16.1) 1.000  Infective endocarditis 2 (8.7) 1 (3.2) 0.578  History of smoking 4 (17.4) 8 (25.8) 0.757  COPD 10 (43.5) 5 (16.1) 0.035  Previous MI 8 (34.8) 10 (32.3) 1.000  Atrial fibrillation 8 (34.8) 15 (48.4) 0.407  NYHA Class III/IV 21 (91.3) 13 (41.9) 0.001  Previous AVR 2 (8.7) 4 (12.9) 1.000  STS-PROM 7.98 ± 3.80 6.6 ± 3.40 0.178  Inoperable/STS-PROM >12% 4 (17.4) 2 (6.5) 0.390 Echocardiographic findings  Median ejection fraction (%) 60 (55–60) 55 (50–60) 0.499  Vmax (m/s) 4.18 ± 0.56 3.98 ± 0.69 0.309  Mean AV gradient (mmHg) 70.4 ± 20.5 69.9 ± 18.8 0.931  Aortic insufficiency 0.179   None 5 (21.7) 8 (25.8)   Trace/trivial 5 (21.7) 3 (9.7)   Mild 11 (47.8) 11 (35.5)   Moderate 1 (4.3) 8 (25.8)   Severe 1 (4.3) 1 (3.2) Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). AV: aortic valve; AVR: aortic valve replacement; COPD: chronic obstructive pulmonary disease; IQR: interquartile range; MI: myocardial infarction; NYHA: New York Heart Association; PROM: predicted risk of mortality; SD: standard deviation; STS: Society of Thoracic Surgeons; Vmax: peak aortic jet velocity. Procedural and postoperative outcomes Compared with pre-FT patients, FT patients had a significantly higher proportion of SC access (77.4% vs 21.7%) but a lower proportion of TAo access (22.6% vs 60.9%) in the TAVR performed (P < 0.001). Similarly, the valve types were significantly different between the 2 groups (P < 0.001). There was also no difference in the median procedural lengths between the 2 groups (P = 0.298). GA was used for all except 1 patient in the FT group. Moreover, only 1 FT patient did not complete the protocol because of multiple comorbidities, including severe liver cirrhosis and a decubitus ulcer, which required an extended stay (Table 2). Table 2: Procedural and postoperative outcomes of patients in the pre-fast-track and fast-track protocols Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). a One patient in the fast-track group underwent the procedure awake under regional anaesthesia and sedation alone. CPB: cardiopulmonary bypass; ICU: intensive care unit; IQR: interquartile range; LOS: length of stay; SD: standard deviation; TAVR: transcatheter aortic valve replacement. Table 2: Procedural and postoperative outcomes of patients in the pre-fast-track and fast-track protocols Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Pre-fast- track (n = 23) Fast- track (n = 31) P-value Procedural details  Urgent status 1 (4.3) 1 (3.2) 1.000  Median procedure length (min) 137 (104–165) 128 (92–160) 0.298  Valve in valve (elective) 1 (4.3) 2 (6.5) 1.000  General anaesthesia 23 (100) 30 (96.8)a 1.000  CPB used 1 (4.3) 0 (0) 0.505  Procedural success 23 (100) 31 (100) 1.000  Alternative access approach 0.001   Subclavian 5 (21.7) 24 (77.4)   Transaortic 14 (60.9) 7 (22.6)   Transapical 4 (17.4) 0 (0)  Device types used 0.001   Sapien 3 (13) 1 (3.2)   Sapien XT 10 (43.5) 2 (6.5)   Sapien 3 3 (13) 20 (64.5)   CoreValve 7 (30.4) 8 (25.8) Postoperative outcomes  Procedural mortality 3 (13) 1 (3.2) 0.301  90-Day mortality 4 (17.4) 1 (3.2) 0.151  New-onset dialysis dependence 0 (0) 0 (0)  Permanent stroke 0 (0) 0 (0)  Permanent pacemaker 2 (8.7) 4 (12.9) 1.000  New atrial fibrillation 2 (8.7) 1 (3.2) 0.569  Cardiac arrest 2 (8.7) 1 (3.2) 0.569  Did not complete fast-track 0 (0) 1 (3.2)  Median ICU time (h) 27 (24–55) 12 (8–28) 0.006  ICU readmission 0 (0) 0 (0)  Median LOS (days) 6 (4–6.5) 5 (3–7) 0.554   LOS ≤ 4 days 6 (26.1) 14 (45.2) 0.098   LOS ≤3 days 4 (17.4) 13 (41.9) 0.081  Post-TAVR echocardiography   Trace/trivial 3 (13) 0 (0)   Mild 0 (0) 2 (6.5)   Moderate/severe 0 (0) 0 (0)  Discharged home 15 (65.2) 19 (61.3) 0.774  30-Day readmission 3 (13) 2 (6.5) 0.377 Continuous variables are presented as mean ± SD unless otherwise noted as median (IQR); categorical variables are summarized as n (%). a One patient in the fast-track group underwent the procedure awake under regional anaesthesia and sedation alone. CPB: cardiopulmonary bypass; ICU: intensive care unit; IQR: interquartile range; LOS: length of stay; SD: standard deviation; TAVR: transcatheter aortic valve replacement. There were no significant differences in procedural mortality (3.2% vs 13.0%, P = 0.301) or 90-day mortality (3.2% vs 17.4%, P = 0.151) between the FT and the p-FT groups, respectively. Similarly, there were no significant differences in procedural complications (such as new-onset atrial fibrillation and permanent pacemaker) or valve performance between the FT and the p-FT groups. Compared with p-FT patients, FT patients had significantly shorter median ICU stays (12 h vs 27 h, P = 0.006) and a trend towards more discharges within 3 days (41.9% vs 17.4%, P = 0.081). Importantly, there were no ICU readmissions, post-procedural strokes, new-onset dialysis dependence or residual moderate or severe aortic insufficiency in either group. Although the 30-day readmission rate was 6.5% for the FT group and 13.0% for the p-FT group, it did not reach statistical significance (P = 0.377). Cost and resource utilization Resource utilization analyses projected a 56% and 17% reduction in the mean ICU time (h) per 100 patients and total LOS (days) per 100 patients, respectively. The overall median direct cost of hospitalization, as measured by the overall relative median cost, was 3% lower (P = 0.87), while the median total cost of hospitalization was reduced by 2% (P = 0.690) after implementation of the FT protocol, mostly due to shorter ICU stays and total LOS, as highlighted in Table 3. Table 3: Cost and resource utilization among patients in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Values presented as median (IQR). a y represents the median cost per TIA patient in the preintervention phase. Outpatient costs and professional billing costs (e.g. physician services) were excluded, but some physician services were included if they were provided for under the hospital’s billed services (e.g. bundled payments for services that include physician care). ICU: intensive care unit; IQR: interquartile range; TIA: transient ischaemic attack. Table 3: Cost and resource utilization among patients in the pre-fast-track and fast-track protocols Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Pre-fast-track (n = 23) Fast-track (n = 31) Total ICU hours 2003 1239  Mean (h) per patient 87 38.7  Hours per 100 patients 8709 3872 % Reduction 56% Total hospital days 160 179  Mean (h) per patient 7 5.8  Days per 100 patients 696 577 % Reduction 17% Total cost ($)  Median cost (approximate)a 56 550 32 000  Median total cost/TIAa 1.6 y (1.4–1.7) 1.5 y (1.4–2.1) % Reduction 2% Total direct cost ($)  Median cost (approximate)a 40 800 14 900  Median direct cost/TIAa 1.3 y (1.2, 1.4) 1.2 y (1.1, 1.6) % Reduction 3% Values presented as median (IQR). a y represents the median cost per TIA patient in the preintervention phase. Outpatient costs and professional billing costs (e.g. physician services) were excluded, but some physician services were included if they were provided for under the hospital’s billed services (e.g. bundled payments for services that include physician care). ICU: intensive care unit; IQR: interquartile range; TIA: transient ischaemic attack. DISCUSSION To our knowledge, limited data exist on the FT protocols for AA-TAVR in the current era [16]. Importantly, our pilot study had several noteworthy findings. First, it demonstrated the safety and feasibility of our novel FT protocol in patients undergoing AA-TAVR. Secondly, clinically observed procedural mortality had decreased to about one-fourth, while 90-day mortality was almost a fifth of that prior to FT protocol implementation, although not statistically significant. Remarkably, there were no cases of post-procedural strokes, new-onset dialysis dependence or ICU readmissions. From a resource utilization standpoint, we demonstrated a substantial reduction in the overall ICU time and hospital LOS among FT patients, with a trend towards earlier hospital discharge—which translated into an overall lower median total and direct cost of hospitalization—without increasing the post-procedural complications or readmissions. TAVR has emerged as a viable alternative for inoperable, high or intermediate STS-risk patients with aortic stenosis [1, 5, 22]. Traditionally, the main access site has been via the femoral artery, because it allows for total percutaneous access and has been shown to have superior outcomes to the non-TF approaches [23, 24]. Unfortunately, certain characteristics, such as peripheral vascular disease and inadequate vessel calibre, still preclude the TF approach in selected patients, creating the need for alternative approaches such as TA, TAo, SC, transcarotid and transcaval [9]. Data from a large UK registry directly compared the TF approach with all the non-femoral approaches [8]. The TAo and TA approaches were found to have significantly worse short- and long-term outcomes. However, the SC and TF approaches had comparable outcomes. A recent study further validated the safety and feasibility of the SC approach in 100 consecutive patients with promising results [25]. A possible explanation as to why the SC approach offers better results than the other non-femoral approaches could be because of its peripheral and less invasive nature, without the need for extensive cut-down or entering the chest cavity. Historically, FT protocols for cardiac surgery were first introduced in the early 90s with the advent of early ventilator weaning and ambulation [26]. They have been shown to hasten the recovery of patients and improve cardiac performance as well as overall progression to a fully functional status [27]. The traditional school of thought holds that monitoring patients for postoperative complications deems conventional (non-FT) protocols indispensable, for a more stable and controlled environment [16]. Furthermore, this specific patient population undergoing TAVR tends to be frailer than other cardiac patients, warranting extra caution throughout the periprocedural period and creating reluctance towards early discharge. Nonetheless, cost and resource utilization arise as important factors to be considered [28]. Keeping these factors in mind, our institution started an FT protocol for TF-TAVR patients in October 2014 and adapted a similar protocol for AA-TAVR patients in September 2015. In our pilot study, FT and p-FT patients had comparable outcomes. Clinically, procedural and 90-day mortality were lower in the FT group, although limited by the small sample size and fewer number of events. Although ICU readmission rates have been reported to be between 2% and 5% in low-risk cardiac surgery patients [16], none of the patients in our series required an ICU readmission, despite their high-risk profile. Moreover, patients in the FT group had significantly shorter ICU stays and a trend towards more discharges within 3 days. This translated to reduced cost and resource utilization and was in line with similar studies except in TF-TAVR [14–17]. For instance, the ‘Vancouver TAVR clinical pathway’ proved successful for proper risk stratification and LOS optimization in 144 consecutive patients undergoing TF-TAVR [15, 29]. Similarly, Babaliaros et al. [14] championed the concept with a comparison between their MA and the standard approach in 142 patients undergoing TF-TAVR. While both approaches had similar safety and efficacy outcomes, the MA was associated with significant reduction of costs ($45 485 vs $55 377), ICU stays (22 h vs 28 h) and hospital LOS (3 days vs 5 days), all P < 0.001. Our pilot study highlights the pivotal role of a multidisciplinary heart team in determining the most appropriate mode of TAVR access, taking into account the operator’s experience and centre’s facilities. Similarly, close interaction among the members of the heart team is equally important. In our experience, several patients were discharged on the post-procedural Day 1 with the SC approach, which did not occur with the other approaches. Moreover, we do not routinely perform the transcarotid or transcaval approach, given our lack of experience with these approaches. Thus, as a team, we adopted the SC-first approach within our novel FT protocol. Taking the MA one step further, we also designed a uniquely tailored regional anaesthesia approach to avoid GA whenever possible, speed up recovery and improve outcomes further. Although we only included our first awake SC-TAVR patient in this study, we have since instituted this as our default alternative, with encouraging early results. Limitations Despite its strengths, our study is subject to all the limitations inherent to a single-centre, retrospective study. Our pilot study is the first of its kind to demonstrate the utility and safety of the FT protocol in AA-TAVR, despite the small sample size which may not be generalizable to other populations. Only 10% of TAVRs are performed via alternative access, and with a case volume of 300 per year, our academic centre only sees about 30 patients with alternative access. It could also be feasible that the improved outcomes may be associated with other policy changes in our TAVR programme or because of the transition from a primarily descending aortic approach to a default strategy of the SC approach (i.e. selection bias, given our FT protocol) rather than with the implementation of the protocol. This may require further validation studies. Moreover, because of the smaller devices available, the FT group may have included fewer significant peripheral vascular disease patients. Notably, there were also significantly fewer patients with New York Heart Association Class III/IV in the FT groups. This imbalance may have influenced the results in favour of the FT group because we did not have enough power to address these using multivariable methods. Our univariate analysis showed that peripheral artery disease was marginally associated with overall mortality, but there was no association with New York Heart Association Class III/IV and our outcomes (P = 0.112). Concerning patient care, we initiated our TF FT programme in November 2014, but our patient management did not change until the incorporation of alternative access FT. Overall, the initial success of our novel FT protocol is worth considering on a wider scale and, to some extent, provides a framework for future studies that examine the feasibility and cost-effectiveness of the FT protocols, especially in high-risk patients undergoing AA-TAVR in the current era. CONCLUSION This small observational study demonstrated the safety of the novel FT protocol for AA-TAVR, resulting in shorter ICU stays and earlier hospital discharge, without increasing procedural complications or readmissions. 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Journal

Interactive CardioVascular and Thoracic SurgeryOxford University Press

Published: Jan 22, 2018

References