The Importance of the Myocardial Factor in the Surgical Treatment of Rheumatic Aortic Stenosis

1. The importance of the "myocardial factor" is considered in a review of 26 patients with massive left ventricular hypertrophy undergoing aortic commissurotomy. 2. The hospital mortality rate was 28 pen cent despite the closed technique employed. This was slightly higher than the mortality rate of 21 per cent in a group of 170 patients with aortic stenosis and small left ventricles. 3. A follow up of 19 cases who survived surgery revealed that 63 per cent had expired as compared to 23 per cent in a group of 134 cases with small left ventricles. The total mortality was 73 per cent in those with massive left ventricles as compared to 39 per cent in the control group. 4. The various limiting factors in cardiac hypertrophy are discussed, and the cardiac catheterization data in nine patients is reviewed. In one case studied by left heart catheterization a significant drop in the systolic gradient across the aortic valve was recorded. 5. It is concluded that this group generally represents poor candidates for the performance of an aortic commissurotomy, especially if a closed technique is employed.