Morbidity and mortality in patients aged over 75 years undergoing surgery for aortic valve replacement

BACKGROUND: The greater longevity observed today has caused an increase in the number of elderly who need surgery. Aortic stenosis is a common condition in this age group. OBJECTIVE: To evaluate morbidity and mortality in people aged 75 years or older who have undergone valvuloplasty or valve replacement surgery for aortic stenosis alone or associated with other injuries. METHODS: We studied 230 consecutive cases between Jan/2002-Dec/2007. Patients were 79.5 ± 3.7 years (75 – 94), and 53.9% were men. In the sample, 68.7% had hypertension, 17.9% had atrial fibrillation, 15.9% were obese, and 14.4% had undergone previous heart surgery. At surgery, 87.4% underwent aortic stent placement, and 12.6% underwent aortic valvuloplasty. RESULTS: The mortality rate was 13.9% (9.4% with isolated aortic stenosis versus 20.9% with an associated procedure, p = 0.023) and the morbidity rate was 30.0% (25.2% with aortic stenosis alone versus 37.4% with an associated procedure, p = 0.068). The most common complications were: low cardiac output (20.2%), renal dysfunction (9.7%), and prolonged ventilatory support (7.9%). In the bivariate analysis, the main predictors of mortality were low cardiac output (RR 10.1, 95% CI: 5.02-20.3), use of intra-aortic balloon (RR 6.6, 95% CI: 3.83-11.4), sepsis (RR 6.77, 95%: 1.66-9.48) and renal dysfunction after surgery (RR 6.21, 95%: 3.47-11.1). As for morbidity, the predictors were: pre-operative renal dysfunction (RR 2.22, 95%: 1.25-3.95), atrial fibrillation (RR 1.74, 95%: 1.16-2.61), and chronic obstructive pulmonary disease (COPD) (RR 1.93, 95%: 1.25-2.97). CONCLUSION: Aortic valve surgery in the elderly is related to a slightly higher mortality rate than in younger patients, and its main risk factors were associated procedures, renal failure, atrial fibrillation, COPD, and sepsis.