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/lp/ou_press/age-dependent-morbidity-and-mortality-outcomes-after-surgical-aortic-fgVxdfseHs
- 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
- 1569-9293
- eISSN
- 1569-9285
- DOI
- 10.1093/icvts/ivy154
- Publisher site
- See Article on Publisher Site
Abstract
Abstract OBJECTIVES This study addressed the assumption of increased morbidity and mortality after surgical aortic valve replacement in patients older than 80 years with severe aortic stenosis. METHODS This prospective study was performed in consecutive patients referred for aortic valve replacement. The age-dependent change in cognitive and physical function, quality of life and rehospitalization and complication rates during the following year and 5-year all-cause mortality were documented. RESULTS A total of 351 patients underwent surgical aortic valve replacement. The death risk at 5 years was 10%, 20% and 34% in patients aged <70 years, 70–79 years and ≥80 years, respectively. Patients aged 70–79 years and ≥80 years had a hazard ratio of 1.88 [95% confidence interval (95% CI) 0.92–3.83, P = 0.08] and 2.90 [95% CI 1.42–5.92, P = 0.003] for mortality, respectively, when compared with patients aged <70 years. The length of stay and rehospitalization rate during the following year were similar between the groups. Patients ≥80 years of age experienced more delirium and infections, whereas the risks of new pacemaker, transient ischaemic attack (TIA) or stroke, myocardial infarction and heart failure were comparable between the age groups. All groups exhibited reduced New York Heart Association class, improved physical quality of life and unchanged mental scores without any clinically significant Mini Mental Status reduction. CONCLUSIONS Elderly patients (≥80 years of age) have important gains in health measures and satisfactory 5-year survival with an acceptable complications rate during the year following surgery. Active respiratory mobilization and the removal of an indwelling urethra catheter can prevent adverse effects, and measures should be taken to prevent delirium and confusion in elderly patients. Clinical trial registration clinicaltrials.gov (NCT 01794832). Surgical aortic valve replacement , Age-dependent survival , Mortality , Hospitalization and complications INTRODUCTION Severe aortic stenosis (AS) predominantly affects the elderly, with a prevalence ranging from 0.2% for those aged 50–59 years to 9.8% for those aged 80–89 years [1]. In Europe, the number of people ≥80 years of age is projected to almost triple from 21.8 million in 2008 to 61.4 million in 2060 [2]. Thus, severe AS is expected to become an expensive public health issue in many countries [3]. Surgical aortic valve replacement (SAVR) has been performed at a steadily increasing rate in more comorbid and elderly patients, with declining mortality, complications, length of postoperative stay and readmission rates [4]. The greatest increase in SAVR has been observed in patients older than 80 years [5]. Recently, transcatheter aortic valve replacement (TAVR) has expanded the pool of operable patients, but the patients who should undergo TAVR versus SAVR remains unclear. Updated guidelines generally recommend SAVR for low-risk patients younger than 75 years and TAVR for high-risk patients older than 75 years and state that TAVR is non-inferior to SAVR in patients with intermediate perioperative risk [6]. However, these results are only valid in comparable groups. The preference to avoid thoracotomy in elderly patients makes it likely that TAVR extends outside the established indications [7]. Thus, there is a growing need for in-depth analyses on outcomes in different age strata to examine important differences that can be used in decision making. We analysed predefined outcomes in age-based cohorts of patients with severe AS to examine assumptions of increased morbidity and mortality after open heart surgery in elderly patients from a contemporary real-life practice. MATERIALS AND METHODS Study design and clinical data collection Oslo University Hospital, Rikshospitalet, is a tertiary referral centre for coronary interventions and cardiothoracic surgery that serves a population of 1.5–2 million inhabitants in southeast Norway [8]. Consecutive patients older than 18 years referred for aortic valve replacement (AVR) due to severe AS between May 2010 and March 2013 were included in this prospective observational study. Routine preoperative examination was supplemented with a standardized 6-minute walking distance (6MWD) test and an interview-based Mini Mental Status (MMS). Sociodemographic and hospitalization data were collected from medical records and health-related quality of life (HRQoL), living conditions and degree of independence were assessed by self-reporting questionnaires. Details on the study design, cohort and collected data were published previously [8]. All patients signed informed consent. The Regional Committee for Medical Research Ethics approved the study, and it was registered at ClinicalTrials.gov (NCT 0179483). Outcomes Predefined outcomes were survival, HRQoL, New York Heart Association (NYHA) class, 6MWD, MMS, length of stay (LOS) for all rehospitalizations and complications during the year following SAVR. The index LOS was calculated as the difference between the date of SAVR and the date of discharge from the local hospital, and unplanned rehospitalization LOS as the difference between the date of admission and the date of discharge. Predefined causes of rehospitalization were explored based on the discharge letters, diagnosis codes (ICD-10) and procedures: infections (respiratory, urogenital or surgery related, i.e. mediastinitis, infection at vein harvesting site and prosthesis infections), new permanent pacemakers, cerebrovascular events, delirium, heart failure and acute coronary syndrome. The cohort was followed up from the date of inclusion until death or the end of follow-up. Follow-up data were censored on 15 March 2017. Complete all-cause mortality data were retrieved from the Norwegian National Cause of Death Registry using the unique Norwegian personalized identification number. Statistical analysis Continuous variables are presented as mean ± standard deviation or median and interquartile range (25th–75th) for skewed data. Normality was assessed by the Shapiro–Wilks test. Categorical variables are presented as proportions. One-way analysis of variance (ANOVA) was used to compare means across age groups; post hoc pairwise comparisons were performed using the Bonferroni correction (dividing the α level by 3). The Kruskal–Wallis test was used for skewed variables; post hoc comparisons were performed using the Mann–Whitney U-test with Bonferroni correction. Categorical variables were compared by the Pearson χ2 test. Changes between baseline and follow-up were addressed within the groups using paired sample t-tests and McNemar’s test as appropriate. Significance was estimated with the Kaplan–Meier survival plots using the log-rank test. A multivariable Cox regression analysis was carried out to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) between age categories corrected for important confounders [high-sensitive troponin T, N-terminal pro brain natriuretic peptide (NT-proBNP) and gender] based on earlier studies [8]. The proportional hazard assumptions were satisfied according to Schoenfeld tests. In the case of missing data, established algorithms were used (i.e. summary scores for SF36), whereas missing clinical variables were excluded for the specific analyses. Inconvenient travel distance and satisfactory follow-up by a local cardiologist was commonly cited as a reason for not attending when contacted by telephone. However, those who did not attend follow-up were encouraged to complete and post their questionnaires. Complete data sets were gathered for rehospitalizations, complications and all-cause mortality. Outcomes are presented in representative age groups: <70 years, 70–79 years and ≥80 years [9]. Reflecting real-life practice, all analyses were performed without stratification of patients requiring SAVR or combined procedures [e.g. SAVR + coronary artery bypass grafting (CABG), aorta graft or another valve repair]. All analyses were performed using STATA version 14 (StataCorp, College Station, TX, USA). A 2-sided P-value <5% was considered significant. RESULTS A total of 573 consecutive patients referred for AVR were mailed an invitation letter prior to their clinical appointment. Among the 480 patients evaluated by the heart team, 351 patients underwent SAVR and were included in the subsequent analyses (Fig. 1). Three patients died while awaiting SAVR and were included in this study as intended to treat. A total of 304 patients attended the 1-year follow-up. Figure 1: View largeDownload slide The study population. SAVR: surgical aortic valve replacement; TAVR: transcatheter aortic valve replacement. Figure 1: View largeDownload slide The study population. SAVR: surgical aortic valve replacement; TAVR: transcatheter aortic valve replacement. Figure 2: View largeDownload slide Age-dependent overall 5-year cumulative survival. Figure 2: View largeDownload slide Age-dependent overall 5-year cumulative survival. Baseline characteristics The cohort was stratified into 3 age groups: 117 patients (33%) were <70 years of age (mean age 60 ± 7 years), 133 (38%) patients were 70–79 years of age (mean age 75 ± 3 years) and 101 (29%) patients were ≥80 years of age (mean age 84 ± 3 years; Table 1). The oldest group was characterized by increased proportions of women living alone, lower body mass index, slightly reduced 6MWD [10], greater comorbidity, increased prevalence of atrial fibrillation, renal failure, coronary artery disease and higher Euro(II)SCORE. The oldest group had a smaller aortic valve area, lower cardiac output, increased signs of cardiac strain with higher high-sensitive troponin T and NT-proBNP levels, lower haemoglobin and a lower creatinine clearance rate (Table 1). Table 1: Baseline characteristics Variables All n = 351 Group A <70 years n = 117 (33%) Group B 70–79 years n = 133 (38%) Group C ≥80 years n = 101 (29%) P-value Demography Mean age (years) 73 ± 10 60 ± 7 75 ± 3 84 ± 3 <0.001a Male sex (%) 58 70 61 42 <0.001 Married or partner (%) 67 81 74 41 <0.001 Body mass index (kg/m2) 26 ± 4 28 ± 5 26 ± 4 25 ± 3 <0.001a Medical history (%) Hypertension 46 39 51 49 0.11 Heart failure 5 3 4 9 0.071 Atrial fibrillation, all types 19 9 19 29 0.001 Diabetes mellitus Types I and II 9 8 11 8 0.70 Pulmonary disease 16 18 17 13 0.55 Kidney disease 4 1 5 8 0.036 Medication (%) Beta-blocker 45 33 47 54 0.006 ACEi/ARB 39 32 43 41 0.17 Calcium antagonist 20 22 20 19 0.80 Statin 55 50 58 55 0.50 Diuretic 31 21 32 39 0.019 Warfarin 17 10 20 23 0.037 Platelet inhibitor 54 48 55 60 0.18 Digitalis 5 2 8 7 0.093 Risk score Euro(II)SCORE, median (IQR) 2 (1–4) 1.2 (0.8–2.2) 2.2 (1.4–3.6) 3.4 (2.4–4.7) <0.001a Echocardiographic measures LVEF (%) 55 ± 10 56 ± 10 55 ± 10 54 ± 10 0.42 Cardiac output indexed (l/min⋅m2) 2.8 ± 0.5 2.9 ± 0.5 2.7 ± 0.5 2.7± 0.5 0.003b Aortic peak velocity (m/s) 4.6 ± 0.7 4.6 ± 0.6 4.5 ± 0.7 4.6 ± 0.7 0.14 Aortic mean gradient (mmHg) 54 ± 16 55 ± 14 52 ± 17 56 ± 16 0.17 Aortic valve area (cm2) 0.7 ± 0.2 0.8 ± 0.2 0.7 ± 0.2 0.6 ± 0.2 <0.001c Angiographically significant coronary artery disease (%) 30 18 35 38 0.002 Biochemical values Haemoglobin (g/dl) 13.8 ± 1.4 14.4 ± 1.4 13.7 ± 1.4 13.1 ± 1.3 <0.001 Creatinine clearance rate (ml/min) 86 ± 32 108 ± 30 71 ± 22 53 ± 14 <0.001a NT-pro-BNP (pmol/l), median (IQR) 70 (30–178) 33 (17–85) 73 (31–172) 160 (63–286) <0.001a hs-TnT (ng/ml), median (IQR) 10 (10–22) 10 (10–14) 12 (10–22) 18 (10–29) <0.001d Six-minute walk test (m) 460 ± 127 522 ± 103 451 ± 124 379 ± 113 <0.001a MMS score 28 ± 2 29 ± 1 28 ± 3 28 ± 2 0.002e Perioperative details Aorta clamp time (min) 74 ± 22 75 ± 23 75 ± 22 70 ± 21 0.21 More than 4 units of red packed cells (SAG) 49 (27) 11 (9) 15 (11) 23 (23) 0.009 Respirator time ≥3 h 46 (39) 52 (39) 37 (37) 0.90 Procedural characteristics <0.001 Isolated AVR 200 (57) 66 (56) 76 (57) 58 (57) AVR + CABG 101 (29%) 23 (20) 41 (31) 37 (37) AVR + SCG 30 (9%) 23 (20) 6 (5) 1 (1) Other (combined procedures) 20 (6%) 5 (4) 10 (8) 5 (5) Variables All n = 351 Group A <70 years n = 117 (33%) Group B 70–79 years n = 133 (38%) Group C ≥80 years n = 101 (29%) P-value Demography Mean age (years) 73 ± 10 60 ± 7 75 ± 3 84 ± 3 <0.001a Male sex (%) 58 70 61 42 <0.001 Married or partner (%) 67 81 74 41 <0.001 Body mass index (kg/m2) 26 ± 4 28 ± 5 26 ± 4 25 ± 3 <0.001a Medical history (%) Hypertension 46 39 51 49 0.11 Heart failure 5 3 4 9 0.071 Atrial fibrillation, all types 19 9 19 29 0.001 Diabetes mellitus Types I and II 9 8 11 8 0.70 Pulmonary disease 16 18 17 13 0.55 Kidney disease 4 1 5 8 0.036 Medication (%) Beta-blocker 45 33 47 54 0.006 ACEi/ARB 39 32 43 41 0.17 Calcium antagonist 20 22 20 19 0.80 Statin 55 50 58 55 0.50 Diuretic 31 21 32 39 0.019 Warfarin 17 10 20 23 0.037 Platelet inhibitor 54 48 55 60 0.18 Digitalis 5 2 8 7 0.093 Risk score Euro(II)SCORE, median (IQR) 2 (1–4) 1.2 (0.8–2.2) 2.2 (1.4–3.6) 3.4 (2.4–4.7) <0.001a Echocardiographic measures LVEF (%) 55 ± 10 56 ± 10 55 ± 10 54 ± 10 0.42 Cardiac output indexed (l/min⋅m2) 2.8 ± 0.5 2.9 ± 0.5 2.7 ± 0.5 2.7± 0.5 0.003b Aortic peak velocity (m/s) 4.6 ± 0.7 4.6 ± 0.6 4.5 ± 0.7 4.6 ± 0.7 0.14 Aortic mean gradient (mmHg) 54 ± 16 55 ± 14 52 ± 17 56 ± 16 0.17 Aortic valve area (cm2) 0.7 ± 0.2 0.8 ± 0.2 0.7 ± 0.2 0.6 ± 0.2 <0.001c Angiographically significant coronary artery disease (%) 30 18 35 38 0.002 Biochemical values Haemoglobin (g/dl) 13.8 ± 1.4 14.4 ± 1.4 13.7 ± 1.4 13.1 ± 1.3 <0.001 Creatinine clearance rate (ml/min) 86 ± 32 108 ± 30 71 ± 22 53 ± 14 <0.001a NT-pro-BNP (pmol/l), median (IQR) 70 (30–178) 33 (17–85) 73 (31–172) 160 (63–286) <0.001a hs-TnT (ng/ml), median (IQR) 10 (10–22) 10 (10–14) 12 (10–22) 18 (10–29) <0.001d Six-minute walk test (m) 460 ± 127 522 ± 103 451 ± 124 379 ± 113 <0.001a MMS score 28 ± 2 29 ± 1 28 ± 3 28 ± 2 0.002e Perioperative details Aorta clamp time (min) 74 ± 22 75 ± 23 75 ± 22 70 ± 21 0.21 More than 4 units of red packed cells (SAG) 49 (27) 11 (9) 15 (11) 23 (23) 0.009 Respirator time ≥3 h 46 (39) 52 (39) 37 (37) 0.90 Procedural characteristics <0.001 Isolated AVR 200 (57) 66 (56) 76 (57) 58 (57) AVR + CABG 101 (29%) 23 (20) 41 (31) 37 (37) AVR + SCG 30 (9%) 23 (20) 6 (5) 1 (1) Other (combined procedures) 20 (6%) 5 (4) 10 (8) 5 (5) Values are presented as mean ±SD and n (%) if not otherwise specified. ACE: angiotensin converting enzyme inhibitors; ARB; angiotensin receptor blockers; AVR: aortic valve replacement; CABG: coronary artery bypass grafting; Euro(II)SCORE: European System for Cardiac Operative Risk Evaluation; hs-TnT: high-sensitive troponin T; IQR: interquartile range; LVEF: left ventricular ejection fraction; estimated creatinine clearance rate (Cockcroft-Gault formula); MMS: Mini Mental Status; NT-proBNP: N-terminal pro brain natriuretic peptide; Other: concomitant other valve repair (often mitral or tricuspid valve), aortic root plastic or aneurism-ectomy; SAG: transfusion with erythrocyte suspension; SCG: supra coronary grafts. a Age, body mass index, Euro(II)SCORE, HgB, NT-proBnP, creatinine clearance rate and 6MWT: significant difference between all groups (P < 0.001). b Cardiac output indexed: A versus B, P = 0.05, and A versus C, P = 0.002. c Aortic valve area: Group A versus Group C, P < 0.001, and Group B versus Group C, P < 0.001. d hs-TnT: Group A versus Group B, P = 0.001; Group A versus Group C, P < 0.001 and Group B versus Group C, P = 0.005. e MMS score: Group A versus Group B, P = 0.029; Group A versus Group C, P = 0.002. Table 1: Baseline characteristics Variables All n = 351 Group A <70 years n = 117 (33%) Group B 70–79 years n = 133 (38%) Group C ≥80 years n = 101 (29%) P-value Demography Mean age (years) 73 ± 10 60 ± 7 75 ± 3 84 ± 3 <0.001a Male sex (%) 58 70 61 42 <0.001 Married or partner (%) 67 81 74 41 <0.001 Body mass index (kg/m2) 26 ± 4 28 ± 5 26 ± 4 25 ± 3 <0.001a Medical history (%) Hypertension 46 39 51 49 0.11 Heart failure 5 3 4 9 0.071 Atrial fibrillation, all types 19 9 19 29 0.001 Diabetes mellitus Types I and II 9 8 11 8 0.70 Pulmonary disease 16 18 17 13 0.55 Kidney disease 4 1 5 8 0.036 Medication (%) Beta-blocker 45 33 47 54 0.006 ACEi/ARB 39 32 43 41 0.17 Calcium antagonist 20 22 20 19 0.80 Statin 55 50 58 55 0.50 Diuretic 31 21 32 39 0.019 Warfarin 17 10 20 23 0.037 Platelet inhibitor 54 48 55 60 0.18 Digitalis 5 2 8 7 0.093 Risk score Euro(II)SCORE, median (IQR) 2 (1–4) 1.2 (0.8–2.2) 2.2 (1.4–3.6) 3.4 (2.4–4.7) <0.001a Echocardiographic measures LVEF (%) 55 ± 10 56 ± 10 55 ± 10 54 ± 10 0.42 Cardiac output indexed (l/min⋅m2) 2.8 ± 0.5 2.9 ± 0.5 2.7 ± 0.5 2.7± 0.5 0.003b Aortic peak velocity (m/s) 4.6 ± 0.7 4.6 ± 0.6 4.5 ± 0.7 4.6 ± 0.7 0.14 Aortic mean gradient (mmHg) 54 ± 16 55 ± 14 52 ± 17 56 ± 16 0.17 Aortic valve area (cm2) 0.7 ± 0.2 0.8 ± 0.2 0.7 ± 0.2 0.6 ± 0.2 <0.001c Angiographically significant coronary artery disease (%) 30 18 35 38 0.002 Biochemical values Haemoglobin (g/dl) 13.8 ± 1.4 14.4 ± 1.4 13.7 ± 1.4 13.1 ± 1.3 <0.001 Creatinine clearance rate (ml/min) 86 ± 32 108 ± 30 71 ± 22 53 ± 14 <0.001a NT-pro-BNP (pmol/l), median (IQR) 70 (30–178) 33 (17–85) 73 (31–172) 160 (63–286) <0.001a hs-TnT (ng/ml), median (IQR) 10 (10–22) 10 (10–14) 12 (10–22) 18 (10–29) <0.001d Six-minute walk test (m) 460 ± 127 522 ± 103 451 ± 124 379 ± 113 <0.001a MMS score 28 ± 2 29 ± 1 28 ± 3 28 ± 2 0.002e Perioperative details Aorta clamp time (min) 74 ± 22 75 ± 23 75 ± 22 70 ± 21 0.21 More than 4 units of red packed cells (SAG) 49 (27) 11 (9) 15 (11) 23 (23) 0.009 Respirator time ≥3 h 46 (39) 52 (39) 37 (37) 0.90 Procedural characteristics <0.001 Isolated AVR 200 (57) 66 (56) 76 (57) 58 (57) AVR + CABG 101 (29%) 23 (20) 41 (31) 37 (37) AVR + SCG 30 (9%) 23 (20) 6 (5) 1 (1) Other (combined procedures) 20 (6%) 5 (4) 10 (8) 5 (5) Variables All n = 351 Group A <70 years n = 117 (33%) Group B 70–79 years n = 133 (38%) Group C ≥80 years n = 101 (29%) P-value Demography Mean age (years) 73 ± 10 60 ± 7 75 ± 3 84 ± 3 <0.001a Male sex (%) 58 70 61 42 <0.001 Married or partner (%) 67 81 74 41 <0.001 Body mass index (kg/m2) 26 ± 4 28 ± 5 26 ± 4 25 ± 3 <0.001a Medical history (%) Hypertension 46 39 51 49 0.11 Heart failure 5 3 4 9 0.071 Atrial fibrillation, all types 19 9 19 29 0.001 Diabetes mellitus Types I and II 9 8 11 8 0.70 Pulmonary disease 16 18 17 13 0.55 Kidney disease 4 1 5 8 0.036 Medication (%) Beta-blocker 45 33 47 54 0.006 ACEi/ARB 39 32 43 41 0.17 Calcium antagonist 20 22 20 19 0.80 Statin 55 50 58 55 0.50 Diuretic 31 21 32 39 0.019 Warfarin 17 10 20 23 0.037 Platelet inhibitor 54 48 55 60 0.18 Digitalis 5 2 8 7 0.093 Risk score Euro(II)SCORE, median (IQR) 2 (1–4) 1.2 (0.8–2.2) 2.2 (1.4–3.6) 3.4 (2.4–4.7) <0.001a Echocardiographic measures LVEF (%) 55 ± 10 56 ± 10 55 ± 10 54 ± 10 0.42 Cardiac output indexed (l/min⋅m2) 2.8 ± 0.5 2.9 ± 0.5 2.7 ± 0.5 2.7± 0.5 0.003b Aortic peak velocity (m/s) 4.6 ± 0.7 4.6 ± 0.6 4.5 ± 0.7 4.6 ± 0.7 0.14 Aortic mean gradient (mmHg) 54 ± 16 55 ± 14 52 ± 17 56 ± 16 0.17 Aortic valve area (cm2) 0.7 ± 0.2 0.8 ± 0.2 0.7 ± 0.2 0.6 ± 0.2 <0.001c Angiographically significant coronary artery disease (%) 30 18 35 38 0.002 Biochemical values Haemoglobin (g/dl) 13.8 ± 1.4 14.4 ± 1.4 13.7 ± 1.4 13.1 ± 1.3 <0.001 Creatinine clearance rate (ml/min) 86 ± 32 108 ± 30 71 ± 22 53 ± 14 <0.001a NT-pro-BNP (pmol/l), median (IQR) 70 (30–178) 33 (17–85) 73 (31–172) 160 (63–286) <0.001a hs-TnT (ng/ml), median (IQR) 10 (10–22) 10 (10–14) 12 (10–22) 18 (10–29) <0.001d Six-minute walk test (m) 460 ± 127 522 ± 103 451 ± 124 379 ± 113 <0.001a MMS score 28 ± 2 29 ± 1 28 ± 3 28 ± 2 0.002e Perioperative details Aorta clamp time (min) 74 ± 22 75 ± 23 75 ± 22 70 ± 21 0.21 More than 4 units of red packed cells (SAG) 49 (27) 11 (9) 15 (11) 23 (23) 0.009 Respirator time ≥3 h 46 (39) 52 (39) 37 (37) 0.90 Procedural characteristics <0.001 Isolated AVR 200 (57) 66 (56) 76 (57) 58 (57) AVR + CABG 101 (29%) 23 (20) 41 (31) 37 (37) AVR + SCG 30 (9%) 23 (20) 6 (5) 1 (1) Other (combined procedures) 20 (6%) 5 (4) 10 (8) 5 (5) Values are presented as mean ±SD and n (%) if not otherwise specified. ACE: angiotensin converting enzyme inhibitors; ARB; angiotensin receptor blockers; AVR: aortic valve replacement; CABG: coronary artery bypass grafting; Euro(II)SCORE: European System for Cardiac Operative Risk Evaluation; hs-TnT: high-sensitive troponin T; IQR: interquartile range; LVEF: left ventricular ejection fraction; estimated creatinine clearance rate (Cockcroft-Gault formula); MMS: Mini Mental Status; NT-proBNP: N-terminal pro brain natriuretic peptide; Other: concomitant other valve repair (often mitral or tricuspid valve), aortic root plastic or aneurism-ectomy; SAG: transfusion with erythrocyte suspension; SCG: supra coronary grafts. a Age, body mass index, Euro(II)SCORE, HgB, NT-proBnP, creatinine clearance rate and 6MWT: significant difference between all groups (P < 0.001). b Cardiac output indexed: A versus B, P = 0.05, and A versus C, P = 0.002. c Aortic valve area: Group A versus Group C, P < 0.001, and Group B versus Group C, P < 0.001. d hs-TnT: Group A versus Group B, P = 0.001; Group A versus Group C, P < 0.001 and Group B versus Group C, P = 0.005. e MMS score: Group A versus Group B, P = 0.029; Group A versus Group C, P = 0.002. Perioperative characteristics All patients ≥80 years of age, 98% of patients who were aged 70–79 years and 39% of the patients younger than 70 years received a bioprosthetic valve with routine recommendation of warfarin in 3 months and subsequent lifelong acetylsalicylic acid (ASA), whereas lifelong warfarin treatment was recommended for patients with mechanical valves. Changes from baseline to follow-up All groups declined in NYHA class and reported gains in physical scores (Physical Component Summary) without any changes in the mental scores (Mental Component Summary) of SF36v2. Only the oldest group had reduced MMS scores (from 28 ± 2 to 27 ± 3, within group difference 0.38, 95% CI 0.13–0.63; P = 0.030). None of the groups showed improvement in 6MWD, and the oldest group declined from 382 (95% CI 351–413) to 347 (95% CI 318–376; P = 0.042) (Supplementary Material, Table S1). Survival outcome A total of 73 (21%) patients died during the median follow-up of 1794 (range 7–2499) days. The total follow-up time was 598 865 patient-days (95% CI 578 456–619 274). The age-based mortality distribution was 10%, 20% and 34% in patients aged <70 years, 70–79 years and ≥80 years, respectively (log-rank P < 0.001; Table 2). Adjusted for important confounders (high-sensitive troponin T, NT-proBNP and gender), Cox regressions analyses revealed that patients aged 70–79 years had a HR of 1.88 (95% CI 0.92–3.83, P = 0.08) and patients aged ≥ 80 years had a HR of 2.90 (95% CI 1.42–5.92, P = 0.003) for mortality when compared with patients younger than 70 years. Table 2: Complete all-cause mortality and length of stay during the following year after surgical AVR Survival (%), 95% CI Group A <70 years (n = 117) Group B 70–79 years (n = 133) Group C ≥80 years (n = 101) P-value 1-Year survival 97 (92–99) 95 (89–97) 94 (87–97) <0.001a 3-Year survival 93 (87–97) 89 (82–93) 80 (71–87) 5-Year survival 89 (82–94) 79 (71–85) 68 (58–78) Hospitalization after SAVR, median (25th–75th) or n (%) Index stay 9 (7–15) 10 (8–15) 10.5 (8–15) 0.19 Patients readmitted during the following year 47 (40 ) 57 (43) 52 (51 ) 0.22 LOS at readmissions after the index stay 5 (2–11) 6 (2–15) 7 (5–17) 0.086 ≥2-week rehospitalization 10 (9) 15 (11) 17 (17) 0.093 Readmitted at least 4 times 6 (5) 9 (7) 6 (6) 0.81 Survival (%), 95% CI Group A <70 years (n = 117) Group B 70–79 years (n = 133) Group C ≥80 years (n = 101) P-value 1-Year survival 97 (92–99) 95 (89–97) 94 (87–97) <0.001a 3-Year survival 93 (87–97) 89 (82–93) 80 (71–87) 5-Year survival 89 (82–94) 79 (71–85) 68 (58–78) Hospitalization after SAVR, median (25th–75th) or n (%) Index stay 9 (7–15) 10 (8–15) 10.5 (8–15) 0.19 Patients readmitted during the following year 47 (40 ) 57 (43) 52 (51 ) 0.22 LOS at readmissions after the index stay 5 (2–11) 6 (2–15) 7 (5–17) 0.086 ≥2-week rehospitalization 10 (9) 15 (11) 17 (17) 0.093 Readmitted at least 4 times 6 (5) 9 (7) 6 (6) 0.81 a Medians were compared with the overall, log-rank test P < 0.001; group-wise comparison: <70 years vs 70–79 years, log-rank P = 0.003; 70–79 years vs ≥80 years, log-rank P = 0.002 and <70 years vs ≥ 80 years, log-rank P < 0.001. AVR: aortic valve replacement; CI: confidence interval; LOS: length of hospital stay (days), defined as minimum one date to the next; SAVR: surgical aortic valve replacement. Table 2: Complete all-cause mortality and length of stay during the following year after surgical AVR Survival (%), 95% CI Group A <70 years (n = 117) Group B 70–79 years (n = 133) Group C ≥80 years (n = 101) P-value 1-Year survival 97 (92–99) 95 (89–97) 94 (87–97) <0.001a 3-Year survival 93 (87–97) 89 (82–93) 80 (71–87) 5-Year survival 89 (82–94) 79 (71–85) 68 (58–78) Hospitalization after SAVR, median (25th–75th) or n (%) Index stay 9 (7–15) 10 (8–15) 10.5 (8–15) 0.19 Patients readmitted during the following year 47 (40 ) 57 (43) 52 (51 ) 0.22 LOS at readmissions after the index stay 5 (2–11) 6 (2–15) 7 (5–17) 0.086 ≥2-week rehospitalization 10 (9) 15 (11) 17 (17) 0.093 Readmitted at least 4 times 6 (5) 9 (7) 6 (6) 0.81 Survival (%), 95% CI Group A <70 years (n = 117) Group B 70–79 years (n = 133) Group C ≥80 years (n = 101) P-value 1-Year survival 97 (92–99) 95 (89–97) 94 (87–97) <0.001a 3-Year survival 93 (87–97) 89 (82–93) 80 (71–87) 5-Year survival 89 (82–94) 79 (71–85) 68 (58–78) Hospitalization after SAVR, median (25th–75th) or n (%) Index stay 9 (7–15) 10 (8–15) 10.5 (8–15) 0.19 Patients readmitted during the following year 47 (40 ) 57 (43) 52 (51 ) 0.22 LOS at readmissions after the index stay 5 (2–11) 6 (2–15) 7 (5–17) 0.086 ≥2-week rehospitalization 10 (9) 15 (11) 17 (17) 0.093 Readmitted at least 4 times 6 (5) 9 (7) 6 (6) 0.81 a Medians were compared with the overall, log-rank test P < 0.001; group-wise comparison: <70 years vs 70–79 years, log-rank P = 0.003; 70–79 years vs ≥80 years, log-rank P = 0.002 and <70 years vs ≥ 80 years, log-rank P < 0.001. AVR: aortic valve replacement; CI: confidence interval; LOS: length of hospital stay (days), defined as minimum one date to the next; SAVR: surgical aortic valve replacement. Hospitalization and complications The median index LOS was 10 (8–15) days, and 156 patients (44%) experienced rehospitalization during the year following SAVR with no between-group differences. Only 6% of patients experienced >4 rehospitalizations during the following year. Among all complications, 55% occurred during the index stay. The majority of surgery-related infections (e.g. superficial wound infections at the thorax or vein harvesting site, mediastinitis and prosthesis infections) were diagnosed during later rehospitalizations. Delirium was more common in the oldest patient group. The need for a new pacemaker, transient ischaemic attack (TIA) or stroke, myocardial infarctions and heart failure did not significantly differ between age groups (Table 3). Table 3: In-hospital complications at the index stay and at readmissions during the following year after AVR by age groups <70 years (n = 117) 70–79 years (n = 133) ≥80 years (n = 101) Total Index stay At readmission Total Index stay At readmission Total Index stay At readmission P-value* All infections 39 (33) 24 (21) 15 (13) 68 (51) 40 (30) 28 (21) 51 (51) 29 (29) 22 (22) 0.008 Respirator 20 (17) 17 (15) 3 (3) 34 (26) 24 (18) 10 (8) 19 (19) 16 (16) 3 (3) 0.22 Urogenital 2 (<1) 1 (<1) 1 (<1) 16 (12) 10 (8) 6 (5) 18 (18) 9 (9) 9 (9) <0.001 Surgical wound relateda 17 (15) 6 (5) 11 (9) 18 (14) 6 (5) 12 (9) 14 (14) 44 10 (10) 0.79 New permanent pacemaker 6 (5) 3 (3) 3 (3) 10 (8) 5 (4) 5 (4) 12 (12) 9 (9) 3 (3) 0.18 TIAs 5 (4) 1 (<1) 4 (3) 3 (2) None 3 (2) None None None 0.11 Strokes 5 (4) 2 (<1) 3 (3) 11 (8) 4 (3) 7 (5) 7 (7) 4 (4) 3 (3) 0.44 TIA and strokes 10 (9) 3 (3) 7 (6) 14 (11) 4 (3) 10 (8) 7 (7) 4 (4) 3 (3) 0.63 Delirium 1 (<1) 1 (<1) None 5 (4) 5 (4) None 8 (8) 5 (5) 3 (3) 0.029 <70 years (n = 117) 70–79 years (n = 133) ≥80 years (n = 101) Total Index stay At readmission Total Index stay At readmission Total Index stay At readmission P-value* All infections 39 (33) 24 (21) 15 (13) 68 (51) 40 (30) 28 (21) 51 (51) 29 (29) 22 (22) 0.008 Respirator 20 (17) 17 (15) 3 (3) 34 (26) 24 (18) 10 (8) 19 (19) 16 (16) 3 (3) 0.22 Urogenital 2 (<1) 1 (<1) 1 (<1) 16 (12) 10 (8) 6 (5) 18 (18) 9 (9) 9 (9) <0.001 Surgical wound relateda 17 (15) 6 (5) 11 (9) 18 (14) 6 (5) 12 (9) 14 (14) 44 10 (10) 0.79 New permanent pacemaker 6 (5) 3 (3) 3 (3) 10 (8) 5 (4) 5 (4) 12 (12) 9 (9) 3 (3) 0.18 TIAs 5 (4) 1 (<1) 4 (3) 3 (2) None 3 (2) None None None 0.11 Strokes 5 (4) 2 (<1) 3 (3) 11 (8) 4 (3) 7 (5) 7 (7) 4 (4) 3 (3) 0.44 TIA and strokes 10 (9) 3 (3) 7 (6) 14 (11) 4 (3) 10 (8) 7 (7) 4 (4) 3 (3) 0.63 Delirium 1 (<1) 1 (<1) None 5 (4) 5 (4) None 8 (8) 5 (5) 3 (3) 0.029 The number of complications in each group, n (%). a Surgical wound-related infections are defined as infection in the operation wound, mediastinum and heart. * TIA: transient ischaemic attack. AVR: aortic valve replacement. Table 3: In-hospital complications at the index stay and at readmissions during the following year after AVR by age groups <70 years (n = 117) 70–79 years (n = 133) ≥80 years (n = 101) Total Index stay At readmission Total Index stay At readmission Total Index stay At readmission P-value* All infections 39 (33) 24 (21) 15 (13) 68 (51) 40 (30) 28 (21) 51 (51) 29 (29) 22 (22) 0.008 Respirator 20 (17) 17 (15) 3 (3) 34 (26) 24 (18) 10 (8) 19 (19) 16 (16) 3 (3) 0.22 Urogenital 2 (<1) 1 (<1) 1 (<1) 16 (12) 10 (8) 6 (5) 18 (18) 9 (9) 9 (9) <0.001 Surgical wound relateda 17 (15) 6 (5) 11 (9) 18 (14) 6 (5) 12 (9) 14 (14) 44 10 (10) 0.79 New permanent pacemaker 6 (5) 3 (3) 3 (3) 10 (8) 5 (4) 5 (4) 12 (12) 9 (9) 3 (3) 0.18 TIAs 5 (4) 1 (<1) 4 (3) 3 (2) None 3 (2) None None None 0.11 Strokes 5 (4) 2 (<1) 3 (3) 11 (8) 4 (3) 7 (5) 7 (7) 4 (4) 3 (3) 0.44 TIA and strokes 10 (9) 3 (3) 7 (6) 14 (11) 4 (3) 10 (8) 7 (7) 4 (4) 3 (3) 0.63 Delirium 1 (<1) 1 (<1) None 5 (4) 5 (4) None 8 (8) 5 (5) 3 (3) 0.029 <70 years (n = 117) 70–79 years (n = 133) ≥80 years (n = 101) Total Index stay At readmission Total Index stay At readmission Total Index stay At readmission P-value* All infections 39 (33) 24 (21) 15 (13) 68 (51) 40 (30) 28 (21) 51 (51) 29 (29) 22 (22) 0.008 Respirator 20 (17) 17 (15) 3 (3) 34 (26) 24 (18) 10 (8) 19 (19) 16 (16) 3 (3) 0.22 Urogenital 2 (<1) 1 (<1) 1 (<1) 16 (12) 10 (8) 6 (5) 18 (18) 9 (9) 9 (9) <0.001 Surgical wound relateda 17 (15) 6 (5) 11 (9) 18 (14) 6 (5) 12 (9) 14 (14) 44 10 (10) 0.79 New permanent pacemaker 6 (5) 3 (3) 3 (3) 10 (8) 5 (4) 5 (4) 12 (12) 9 (9) 3 (3) 0.18 TIAs 5 (4) 1 (<1) 4 (3) 3 (2) None 3 (2) None None None 0.11 Strokes 5 (4) 2 (<1) 3 (3) 11 (8) 4 (3) 7 (5) 7 (7) 4 (4) 3 (3) 0.44 TIA and strokes 10 (9) 3 (3) 7 (6) 14 (11) 4 (3) 10 (8) 7 (7) 4 (4) 3 (3) 0.63 Delirium 1 (<1) 1 (<1) None 5 (4) 5 (4) None 8 (8) 5 (5) 3 (3) 0.029 The number of complications in each group, n (%). a Surgical wound-related infections are defined as infection in the operation wound, mediastinum and heart. * TIA: transient ischaemic attack. AVR: aortic valve replacement. DISCUSSION Despite older age, more comorbidities with reduced renal function and increased preoperative cardiac strain, patients ≥80 years of age had excellent survival after SAVR (Fig. 2). The typical >80-year-old AS patient was a single-living female who was mentally well oriented and reasonably mobile with an enhanced risk for atrial fibrillation and coronary artery disease based on higher levels of NT-proBNP and reduced renal function, using beta-blockers, diuretics and warfarin. These patients more often underwent an AVR + CABG with very satisfactory 3- to 5-year outcomes. However, the survival data for TAVR in this population are insufficient. The Placement of Aortic Transcatheter Valves (PARTNER) and transcatheter aortic-valve replacement with a self-expanding prosthesis (PIVOTAL) trials have documented beneficial 5-year survival and 3-year survival after TAVR in inoperable patients when compared with medical treatment and for high-risk patients when compared with SAVR [11, 12]. A recent meta-analysis indicated concerns due to increased mortality after TAVR in low-risk patients after 2 years [13]. Unresolved issues, such as the selection of appropriate anticoagulation therapy, paravalvular leak, valve thrombosis, valve durability and consequences of increased pacemaker need, imply a cautious attitude for TAVR in intermediate- and low-risk groups [14]. The enthusiastic preference of TAVR in elderly patients assessed to have low or intermediate risk is questionable, especially in light of satisfactory results after SAVR [15]. The satisfactory 5-year survival in this study lends evidence of SAVR as a good option for elderly patients evaluated for AVR. It is important that physicians convey balanced evidence in their choice of intervention, as patients base their decisions and preferences on our recommendations. Functional class and symptoms All groups experienced improvements, as measured by reductions in NYHA class and satisfactory gains in HRQoL. Recent randomized controlled trials indicate that TAVR results in greater initial improvement in HRQoL when compared with SAVR, but this difference disappears at 1 year [16]. The oldest group exhibited a clinically insignificant decline in the MMS score. The majority of our patients were living independently at home 1 year after surgery. Length of stay and rehospitalization The overall 1-year readmission rate of 44% (156/351) is congruent with other studies [17]. In a cohort of patients with a mean age of 82 years, TAVR patients were reported to have a readmission rate of 43% [18]. Despite much focus on the advantages and shorter rehabilitation after TAVR procedures, data addressing this topic are scarce. High readmission rates are observed in both SAVR and TAVR [18], underscoring the need for prophylactic tools and rehabilitation. Murugiah et al. [17] documented an age-related reduction in the index LOS and a declining rate of readmission over a 10-year period after SAVR. Complications Infection was the most common complication (62%) and a frequent reason for rehospitalization. Urinary infections were more common among the oldest patients. The postoperative use and duration of indwelling urethra catheters (IUCs) were not analysed. In the literature, 14–38% of IUCs are placed without a specific medical indication, and inappropriate IUC use is associated with older age, greater likelihood of urinary tract infection, longer duration of catheterization, greater risk of death and longer hospital stay [19]. The oldest group had an increased incidence of delirium, which is associated with cardiac surgery and carries the risk of many negative consequences [20]. However, increased awareness and preventive interventions may reduce such complications. Overall, our findings do not support the assumption that elderly patients are more prone to complications (except for delirium) or more frequent or longer hospitalization after SAVR. Important preoperative and perioperative differences The elderly did well despite having more comorbidities, with higher Euro(II)SCORE and levels of biochemical markers of cardiac strain. All groups had a similar aortic clamping time and proportions requiring >3 h in the respirator and intensive care unit stays. Notably, the oldest group had a greater requirement for a transfusion of >4E transfusion with erythrocyte suspension (SAG), which is an independent risk factor for nosocomial infection [21]. However, there were important differences in concomitant surgical procedures performed among the 3 age groups, complicating comparisons of postoperative course and the impact of surgery. Age considerations in aortic valve replacement Increasing age is considered an independent determinant of postoperative mortality and complications [22, 23]. However, when patients are stratified based on established risk scores, long-term survival is reportedly comparable between age groups [9]. Thus, guidelines recommend that the selection and modes of intervention should be founded on established preoperative risk scores rather than just age. Our data support this recommendation, revealing that all age groups had satisfactory survival outcomes after SAVR, with comparable morbidity in the first postoperative year. Thus, TAVR is currently a good option in inoperable or high-risk patients, satisfying criteria used in randomized controlled trials showing non-inferior results. Limitations This study has several limitations. First, it was not a randomized trial, and bias in the selection of treatment is difficult to correct or assess. The comparison of surgical patients is only useful for providing contemporary data from the complex clinical setting of a tertiary centre. Second, patient self-select bias (inclusion of individuals motivated to seek referral to a tertiary centre) and referral bias (local cardiologists more likely to refer their healthiest elderly patients) are likely present, such that our results may not be generalizable to all patients with severe AS. Third, the aetiology of rehospitalization and complications may be biased by differences in practices and the level of assets used to confirm a diagnosis at different hospitals. For example, local practices and experiences likely influence the threshold for treating pneumonia after thoracotomy or urinary tract infections, as well as the LOS after surgical AVR. We cannot exclude that the observed comparable complication rates may be due to a small number of patients in each group. Thus, further studies are warranted. CONCLUSIONS SAVR was associated with satisfactory survival and substantial symptom relief in all age groups. No important differences in morbidity were observed during the year after thoracotomy. Active respiratory mobilization and the removal of the IUC can prevent numerous adverse events, and preventive measures should be taken to prevent delirium and confusion in elderly patients. The decision between SAVR and TAVR must be made on an individual basis, accounting for established risk factors and through discussion in a heart team setting, rather than just based on age. SUPPLEMENTARY MATERIAL Supplementary material is available at ICVTS online. ACKNOWLEDGEMENTS The authors acknowledge Wenche Stueflotten, Caroline Rudi and Sonia Aslam for providing important assistance in terms of data collection and the logistic flow of study participants. Funding This work was supported by a grant from the Norwegian Health Association and Inger and John Fredriksen to the Department of Cardiology, Rikshospitalet, Norway. Conflict of interest: none declared. REFERENCES 1 Eveborn GW , Schirmer H , Heggelund G , Lunde P , Rasmussen K. The evolving epidemiology of valvular aortic stenosis. the Tromso study . Heart 2013 ; 99 : 396 – 400 . Google Scholar CrossRef Search ADS PubMed 2 Vasques F , Messori A , Lucenteforte E , Biancari F. 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Journal
Interactive CardioVascular and Thoracic Surgery – Oxford University Press
Published: May 9, 2018