[Aortic subvalvular obstructions. Anatomical forms and surgical treatment of 82 consecutive cases]

The authors report their experience of surgery for subvalvular aortic obstruction in 82 patients aged from 4 to 44 years (mean 15 years). Nearly one-half of the patients presented with symptoms; the others were operated upon for various reasons: gradient exceeding 60 mmHg, development or aggravation of aortic regurgitation, positive exercise test, electrocardiographic or echocardiographic signs of left ventricular repercussions. Nineteen children had previously undergone surgery for another malformation, but the subvalvular aortic obstruction had either been missed during this first operation or had developed subsequently. The diaphragmatic pattern was the most frequent (62 cases); the fibromuscular pattern was less common (9 cases) and the tunnel pattern (6 cases) was regularly associated in this series with hypoplasia of the aortic ring. Obstruction due to faulty insertion of the mitral valve was encountered on 3 occasions. The operative technique for each anatomical pattern is described. Tunnel obstructions did not require primary aortoventriculoplasty without prosthetic valve replacement of apicoaortic conduits. In addition to treatment of associated lesions (including 4 cases of ventricular septal defect), 9 aortic commissurotomies, 6 aortic valvuloplasties and 4 aortic valve replacements were performed. The transaortic gradient was dramatically improved. The aortic regurgitation murmur subsided with or, usually, without valvuloplasty.(ABSTRACT TRUNCATED AT 250 WORDS)