Myocardial apoptosis predicts postoperative course after aortic valve replacement in patients with severe left ventricular hypertrophy

BACKGROUND AND AIM OF THE STUDY: Myocardial apoptosis has been implicated in heart failure and post-infarct remodeling. In some patients with severe aortic stenosis, delayed valvular replacement is associated with a poor in-hospital outcome. The study aim was to evaluate the impact of cardiomyocyte apoptosis on the postoperative course after aortic valve replacement (AVR) for severe aortic stenosis. METHODS: During elective AVR, myocardial biopsies were obtained from the left ventricle of 11 patients with severe left ventricular hypertrophy (LVH), and the samples analyzed for apoptosis. RESULTS: The mean apoptotic rate was 10.4 +/- 3.7 per thousand. (range: 5-16 per thousand). The apoptotic rate correlated directly with preoperative NYHA functional class, duration of intensive care unit (ICU) stay, number of days of postoperative acute renal insufficiency, and serum level of troponin T at 24 h; the apoptotic rate correlated inversely with cardiac index at 24 h postoperatively. At multivariate analysis, the apoptotic rate and left ventricular mass index were independent predictors of prolonged ICU stay. The apoptotic rate and duration of cardiopulmonary bypass were predictive of the duration of postoperative acute renal insufficiency. CONCLUSION: The study results showed an association between myocardial apoptosis and postoperative outcome in patients with severe LVH submitted for AVR. Non-invasive correlates of apoptosis may be introduced as a means of identifying patients at a higher operative risk, and may help in the evaluation of asymptomatic patients with severe aortic stenosis. Anti-apoptotic strategies before and during surgery would possibly ameliorate the surgical results