Survival after valve replacement for aortic stenosis: implications for decision making

Recommendations for aortic valve replacement in severe aortic stenosis are based primarily on the presence of symptoms. However, the onset of symptoms is often insidious, potentially leading to delayed intervention and suboptimal results. Identifying factors that reduce the survival of patients undergoing aortic valve replacement could lead to revised treatment guidelines and improved outcomes.

We conducted a single-center observational clinical study of 3049 patients with aortic stenosis who underwent native aortic valve replacement with a single type of bioprosthesis. The primary end point was all-cause mortality from the date of operation. Multivariable analysis of risk factors for death was performed in the multiphase hazard function domain.

The presence of severe left ventricular hypertrophy at operation, which preceded symptoms in 17% of patients, was associated with decreased survival. This effect was magnified by the severity of aortic stenosis (P = .02) and use of small prostheses (P = .01). The presence of left ventricular dysfunction reduced survival (P = .0003). Although older age was a risk factor for death (P < .0001), elderly patients had survival comparable to their age, race, and sex-matched cohorts, whereas younger patients had worse than expected survival that was further diminished with insertion of a small prosthesis (P = .01).

To optimize survival, earlier aortic valve replacement should be considered even in asymptomatic patients before severe left ventricular hypertrophy or dysfunction develops. In younger patients, the largest possible prosthesis should be implanted to minimize residual gradient; in elderly patients, complex operations just to insert larger prostheses should be avoided.