Perioperative and long-term outcomes following aortic valve replacement: a population cohort study of 4124 consecutive patients.

OBJECTIVE: Because of increasing life expectancy, more patients require valve replacement for aortic stenosis. We aimed to determine perioperative and long-term outcomes, the factors associated with these and whether they have changed over time.
METHODS: We undertook a retrospective cohort study of all 4124 patients, who underwent isolated, primary aortic valve replacement in Scotland between April 1996 and March 2009 inclusive.
RESULTS: Annual operations increased by 68%, from 261 to 439. The overall risk of dying within 30 days, 5 years and 10 years was 3.4%, 19.9% and 38.5%, respectively. Over 10 years' follow-up, 4.4% underwent further valve surgery, 7.9% suffered a stroke and 5.3% a myocardial infarction. Age, renal impairment and urgency were predictors of both perioperative and long-term death. Perioperative death was associated with left-ventricular impairment and long-term death with respiratory disease, diabetes and deprivation. Over the 13 years, there was an increase in median age (from 66 to 69 years, p < 0.001), diabetes (from 1.9% to 12.6%, p < 0.001), hypertension (from 26.4% to 56.1%, p < 0.001), cerebrovascular disease (from 3.7% to 9.8%, p < 0.001), respiratory disease (from 6.6% to 9.7%, p = 0.020) and previous myocardial infarction (from 0.6% to 5.8%, p < 0.001), but the risk of perioperative death fell from 6.5% to 3.1% (odds ratio (OR) 0.87, 95% confidence interval (CI) 0.83, 0.92, p < 0.001) per year.
CONCLUSIONS: Patients undergoing aortic valve replacement have a poor risk profile. Over time, their numbers, age and co-morbidity have increased. In spite of these, there has been a significant reduction in the risk of perioperative death.