Results of Aortic Diaphragm Surgery in Senegal: About 20 Cases

Introduction: The subaortic diaphragm is a semilunar or circular membrane that is inserted into both the septal wall of the left ventricle and the base or adjacent part of the ventricular surface of the large mitral valve. It represents for 8-20% of all obstacles to left ventricular ejection. Material And Methods: This is a retrospective and descriptive study of patients with aortic stenosis under aortic diaphragmatic surgery operated over an 11-year period (January 2004-December 2015). Our study included 20 patients, 13 of which were male. The sex ratio was 1.85. The average age of patients was 16.6 years [4-51 years]. Stage 2 dyspnea (NYHA) was the primary reason for consultation (17 patients). The heartbeat was regular sinus rhythm in 17 patients. Transthoracic echocardiography (TTE) found left ventricular hypertrophy in 19 patients. The average trans-aortic gradient was 55.68mmHg [24 - 92.5 mmHg]. Aortic insufficiency (IA) was found in 14 patients. An associated congenital heart defect was found in 9 patients. The approach was vertical median sternotomy and transverse aortotomy. The diaphragm was circular in 12 patients and semicircular in 8 patients. The aortic valve was tricuspid in 18 patients and bicuspid in 2 patients. The mean duration of extracorporeal circulation (ECC) was 74.66 minutes [35-119mn] and the mean duration of aortic cross-clamping was 49.11 minutes [20-102mn]. Results: After surgery, disorders of rhythm and conduction were present in 6 patients. At transthoracic ultrasound, left ventricular dysfunction was noted in 3 patients. A tamponade occurred in 1 patient justifying emergency drainage. Two recurrences of subaortic diaphragm were noted, one of which was reoperated after 9 years with a resection of the membrane and a replacement of the aortic valve by a mechanical prosthesis. One death was recorded four days postoperatively. The average postoperative gradient was 21.46mmhg. The average follow-up time was 38 months [5 months - 115 months].