Left ventricular mass index in aortic valve surgery: a new index for early valve replacement?

OBJECTIVE Increased left ventricular mass index has been associated with higher mortality. We analyze the effect of increased left ventricular mass index on outcomes in patients undergoing aortic valve replacement. METHODS Echocardiographic left ventricular dimensions were used to calculate left ventricular mass index in 614 patients who underwent aortic valve replacement between June 1993 and November 2001. Left ventricular mass index was considered increased if higher than the value of the superior decile (277 g/m(2) in males and 251 in females). RESULTS Mean left ventricular mass index was: 178+/-111 g/m(2), and increased index was considered in 9.9% of patients. Postoperative complications (low cardiac output syndrome, respiratory failure, arrhythmias, pneumonia and mediastinitis), median length of hospital stay: 12 days (6-57) versus 11 days (5-51), and in-hospital mortality (11.4, 3.2%, P<0.01) were higher in patients with increased left ventricular mass index. Multivariable analysis identified increased left ventricular mass index (odds ratio: 5.6; 95% confidence interval: 1.2-25.0; P=0.02) and other three variables: age (P=0.04), history of chronic renal failure (P=0.03) and cardiopulmonary bypass time (P=0.004), as independent predictors of early mortality. CONCLUSIONS Increased left ventricular mass index is associated with an in-hospital adverse outcome and a significantly higher in-hospital mortality in patients undergoing aortic valve replacement. Outcomes in asymptomatic patients could be improved before a clinically significant increase in left ventricular mass index. Further studies should be performed to determine the usefulness of this index in selecting patients for earlier aortic valve replacement.