[Surgical treatment of aortic subvalvular obstruction. Experimental study of a new approach].

The aortic subvalvular region is difficult to approach. The results after resection through a pure transaortic approach are often unsatisfactory. An aorto-septal approach derived from the Konno-Rastan aortoventriculoplasty was experimented in animals. This technique involves opening the ascending aorta and the pulmonary infundibulum, section of the aortic annulus at the left anterior commissure and incising the muscular interventricular septum. The results of this aorto-septal approach show: - that the whole left ventricular ejection tract can be exposed; - that the incision can be closed without damage to the heart, i.e. creation of atrioventricular block, and with reconstruction of an intact interventricular septum and a normally functioning aortic valve. This approach could therefore be used for the treatment of diffuse subvalvular aortic stenosis: - subaortic fibromuscular tunnel without hypoplasia of the aortic ring (one personal case has already been reported); - severe forms of hypertrophic obstructive cardiomyopathy with asymmetric septal hypertrophy.