Indices Predicting Long-term Survival after Valve Replacement in Patients with Aortic Regurgitation and Patients with Aortic Stenosis

Abstract

The long-term results of aortic valve replacement were reviewed in all 88 patients with isolated aortic regurgitation and all 103 patients with isolated aortic stenosis who were operated upon at the National Heart and Lung Institute from 1963 to 1971. Survival curves were compared to determine whether any of 30 preoperative clinical and hemodynamic findings correlated with long-term survival. The indices that were of predictive value in patients with aortic regurgitation were found to be different from those in aortic stenosis. Symptoms, cardiac index, and cardiothoracic ratio did not influence survival in patients with aortic regurgitation. In these patients, survival was inversely correlated with the level of left ventricular end-diastolic pressure (LVEDP): six-year survival was 74% in patients with LVEDP ≤ 10 mm Hg, 41% with LVEDP 11-20 ( P < .05), and 30% with LVEDP > 20 ( P < .01). Survival also was lower in patients with aortic regurgitation who had elevated pulmonary arterial and left atrial pressures, and in patients with electrocardiographic evidence of severe left ventricular hypertrophy (LVH). Using an LVH point score method (Romhilt-Estes), 56% of patients with a score ≤ 6 survived six years; 29% with a score > 6 survived ( P < .02). Survival in aortic stenosis did not relate to any of the above, but did correlate with preoperative functional class. Five-year survival was 70% in class II, but only 40% in class III-IV ( P < .02). Moreover, cardiothoracic ratio in patients with aortic stenosis correlated with survival in an unexpected way. Eleven of 31 patients with cardiothoracic ratio ≤ .45 had sudden unexplained death postoperatively, compared to only six of 72 patients with cardiothoracic ratio > .45 ( P < .01). This difference did not correlate with postoperative hemodynamic measurements, including magnitude of the transprosthetic gradient. We conclude that certain preoperative indices are of value in predicting long-term prognosis after valve replacement for aortic regurgitation and for aortic stenosis, but that the specific predictive indices for the two groups differ.