ABSTRACT
BACKGROUND: Aortic valve replacement (AVR) can be performed safely in selected elderly patients with aortic stenosis (AS). However, the survival benefits of AVR over conservative treatment have not been convincingly demonstrated in AS patients aged above 80. AIM: To investigate the outcomes of patients aged 80 and over with symptomatic, severe AS and by analyzing the effects of patient's choice in either agreeing or refusing to undergo AVR, determine the survival benefits afforded by AVR. DESIGN: Cohort study. METHODS: Subjects aged 80 and over with severe symptomatic AS, diagnosed between 2001 and 2006 were segregated into three groups: subjects who underwent AVR (Group A); patients who were fit for AVR but declined surgery due to personal choice (Group B) and those who were not fit for surgery and were managed conservatively (Group C). Follow-up was conducted by out-patient attendances, review of medical records and telephone interviews. The primary endpoint was all-cause mortality. RESULTS: A total of 103 patients (86.0 +/- 4.2 years, 41% male) were identified and no patient was lost during follow-up. In Group A (n = 17), all 15 patients who underwent AVR were alive after 3.6 +/- 1.4 years follow-up and 2 died whilst awaiting AVR. Seventy-four percent of Group B (n = 24) and 76% of Group C (n = 62) died during follow-up. Group A had significantly better survival than B and C. (P < 0.01) Amongst patients fit for AVR with similar operative risks (Groups A and B), refusal to undergo surgery (hazard ratio 12.61, P = 0.001) was the only predictor of mortality in a multivariate model. CONCLUSION: For elderly AS patients fit for surgery, the patient's decision to refuse AVR is associated with a >12-fold increase in mortality risk. These findings have significant implications for informed decision-making when managing the fit, elderly patient with AS.
Subject(s)
Aortic Valve Stenosis/surgery , Aortic Valve/surgery , Heart Valve Prosthesis Implantation/mortality , Treatment Refusal/statistics & numerical data , Aged, 80 and over , Aortic Valve Stenosis/mortality , Cohort Studies , Decision Making , Female , Heart Valve Prosthesis Implantation/psychology , Humans , Male , Prognosis , Survival Analysis , Treatment Outcome , Treatment Refusal/psychologyABSTRACT
BACKGROUND: Cardiac resynchronisation therapy improves peak oxygen uptake (peak VO(2)) 3-9 months after device implantation. In chronic heart failure, total isovolumic time (t-IVT) is a major determinant of peak VO(2) and of cardiac output at peak dobutamine stress. In selected patients, resynchronisation can instantaneously shorten t-IVT. We sought to determine the acute effect of resynchronisation on exercise performance and determine, with pharmacological stress echocardiography, the mechanism underlying this effect. METHODS AND RESULTS: Twenty-two patients with resynchronisation were studied within 3 months after device implantation. On a single study day, sequential cardiopulmonary exercise tests were performed during native activation (left bundle branch block) and resynchronisation (atrio-biventricular pacing) in random order. Total-IVT and cardiac output (at rest and peak dobutamine stress) were then measured in each activation mode. Resynchronisation acutely increased peak VO(2) by 1.6 (SD 1.5) ml/kg/min (p<0.001) and shortened peak stress t-IVT by 10 (SD 7) s/min (p<0.001), with the effects in individual patients showing a correlation (r = -0.46, p<0.05). Amongst all measurements during native activation, the best predictor of gain in peak VO(2) from resynchronisation was peak stress t-IVT (r = 0.71, p<0.001) with every increment of 5 s/min of peak stress t-IVT during native activation predicting an 8% gain in peak VO(2). No conventional measures during native activation at rest or on stress (including QRS duration, Tei index, tissue Doppler intraventricular delay, and resting t-IVT) added significant additional information. CONCLUSIONS: In eligible patients, resynchronisation can acutely augment peak VO(2), possibly through a mechanism of t-IVT shortening. Under native activation, long t-IVT during peak stress is the single best predictor of acute resynchronisation-mediated increment in peak VO(2).
Subject(s)
Cardiac Pacing, Artificial/methods , Cardiac Volume/physiology , Heart Failure/therapy , Aged , Echocardiography, Stress/methods , Exercise Test/methods , Exercise Tolerance , Female , Humans , Male , Oxygen Consumption/physiology , Stroke Volume/physiologyABSTRACT
The COMPANION trial was terminated prematurely after recruiting 1600 patients, as initial results clearly and for the first time demonstrated survival benefit of resynchronisation and combined device (biventricular pacemaker with defibrillator capacity) therapy in heart failure. The combined primary end-points of all-cause mortality and all-cause hospitalisation in patients with dilated cardiomyopathy and heart failure of poor functional class was reduced by 20% with cardiac resynchronisation therapy (CRT) with or without defibrillator capacity. More importantly, mortality was reduced by 40% (from 19% to 11%) in patients implanted with combined devices, while CRT alone gave an intermediate mortality of 15%.