Results of aortoventriculoplasty in 21 consecutive patients with left ventricular outflow tract obstruction.

Results of aortoventriculoplasty (AVP) are reported in 21 patients with various types of left ventricular outflow tract obstruction (LVOTO). The concept of AVP is based on creating a surgical aortoseptal defect which is patched to provide the largest possible outflow tract to the left ventricle. Lesions consisted of isolated diffuse fibromuscular subaortic stenosis in six patients, diffuse subaortic stenosis and associated other cardiovascular anomalies in five, hypoplastic aortic anulus in two, idiopathic hypertrophic subaortic stenosis (IHSS) in two, and stenosis of a previously implanted aortic valvular prosthesis in three patients. Ten patients had had at least one unsuccessful previous surgical attempt to relieve the LVOTO. The coexisting mitral incompetence in IHSS disappeared after AVP alone. Immediate postoperative hemodynamic results were excellent in all cases. Postoperative death in five patients was due to advance myocardial failure in two, brain damage in one, transection of a dominant septal artery in one, and severe acidosis with renal failure in the last case. However, in the last 16 patients (17 operations) the only death (5.8 percent) was that caused by uncontrollable acidosis. Follow-up results indicate that 16 patients are clinically doing well, and hemodynamic studies in 14 patients are rated as excellent or good from 1 to 25 months postoperatively. It is concluded that AVP is an effective operation for managing all types of LVOTO and can be used routinely with an acceptably low mortality rate.