[Conduction disorders and aneurysms of the sinus of Valsalva].

A series of 15 sinus of Valsalva aneurysms (SVA) admitted between 1961 and 1981 was reviewed to analyse associated conduction defects. It comprised 11 men and 4 women; the mean age was 31 years (range 16 to 53). The diagnosis of SVA was made at the time of rupture (4 cases), during investigation of associated cardiac disease (8 cases), at surgery (1 case) and during advanced conduction disorders (2 cases). All patients underwent catheterisation and angiography. Endocavitary electrophysiological studies were performed in 3 patients. Eight out of 15 patients had conduction defects which comprised: incomplete right bundle branch block (2 cases), atrioventricular block (AVB) (6 cases). Endocavitary investigation of 3 of the 6 AVB showed conduction defects at several levels: sino atrial, suprahisien, intrahisian and infrahisian blocks (1 case); transient complete AVB with 1 degree and 2 degree intrahisian block (1 case); complete AVB, six years after correction of SVA, due to infrahisian block (1 case). Thirteen of the 15 patients underwent surgery; none of the 9 cases of SVA without conduction defects before surgery developed conduction defects. Four of the 6 cases of AVB required permanent pacing; there was 1 postoperative death. One patient was not operated. These conduction defects were caused by the close relationship of the SVA to the intracardiac conduction pathways. The right anterior was the most commonly affected sinus. The investigation of AV conduction should be systematic in cases of SVA, and, conversely, the finding of AVB in young patients should alert the physician to the possibility of a SVA.