Evaluation of operative risk in elderly patients undergoing aortic valve replacement: the predictive value of operative risk scores

Abstract

Objectives: An increasing number of elderly patients develop aortic valve disease requiring surgery. Operative risk scores are currently used to identify patients at high operative risk who may benefit from interventional treatment options. The aim of this study was to analyze the predictive value of these risk scores in geriatric patients undergoing aortic valve replacement.

Methods: We reviewed data of 1,245 elderly patients who underwent aortic valve replacement with or without additional bypass surgery from 2000-2007. Patient data were derived from a prospective registry at the Department of Cardiac Surgery at Albertinen-Hospital in Hamburg, Germany.

Results: Hospital mortality was 2.56% in isolated valve replacement and 3.38% in patients who had additional bypass surgery (p = ns). Age >80 years (OR 1.7; 95% CI: 1.3-3.3) and renal failure (OR 1.6; 95% CI: 1.1-2.5) were significantly associated with in-hospital death. All scores overestimated operative mortality. The median logistic EuroSCORE was 11.56% (interquartile range: 7.01-18.96), median STS score 13.9% (10.3-16.2); and median Ambler score 7.2% (4.1-9.3). There was a significant correlation of the STS score with operative mortality (Spearman's rank coefficient: 0.68), but not with EuroSCORE (Spearman's rank coefficient: 0.11) or Ambler score (Spearman's rank coefficient: -0.17).

Conclusion: Current risk scores overestimate operative risk in geriatric patients undergoing aortic valve replacement substantially. Of the risk scores evaluated, only STS score correlated significantly with operative mortality. Operative risk scores aimed specifically at geriatric patients may be necessary to accurately identify patients at high operative risk who benefit from non-surgical treatment options.