Hemodynamic findings before and after aortoventriculoplasty (AVP).

Between June 1974 and July 1981, aortoventriculoplasty (AVP) has been applied in 57 patients with several types of left ventricular outflow tract obstruction ranging in age from 5 to 34 years. There were 7 early deaths (mortality 12%); 5 of these occurred in the first 10 patients operated upon. Eighteen patients developed complete right bundle branch block or left anterior hemiblock or both; in another patient a transient complete left bundle branch block occurred postoperatively. Two patients had a permanent AV-block. In contrast to the unsatisfactory hemodynamic results of previous conventional operations, AVP reduced the mean residual resting gradient across the left ventricular outflow tract from 85 +/- 17 mmHg (range 60 to 140 mmHg) to 12 +/- 12 mmHg (range 0 to 65 mmHg). Except in 2 patients, this gradient did not increase by more than 15 mmHg under Isoproterenol (range 0 to 35 mmHg). In 25% of the restudied patients the left ventricular enddiastolic pressure returned to normal after AVP. In 3 patients a small ventricular septal defect in the area of the patched septal incision was detected by oximetry and angiocardiography, whereas mild aortic regurgitation was present in another 6 patients. Residual gradients across the right ventricular outflow tract in 5 patients ranged from 17 to 40 mmHg. This study shows the hemodynamic results obtained by AVP to be superior to those of conventional surgery. The major advantage of AVP as compared to total homograft replacement of the aortic root and to the apico-aortic conduit operation, is its applicability in all types of left ventricular outflow tract obstruction.