Subaortic stenosis: Anatomic Patterns and Associated Cardiovascular Abnormalities

Kim, Seon Young; Ma, Jae Sook

Abstract

Subaortic stenosis refers to stenotic status of outflow from the ventricle beneath the aortic valve due to various anatomic abnormalities. Because of the progressiveness and the occurrence of aortic insuffi ciency, the presence of even mild subaortic stenosis warrants consideration of elective operation. A retrospective study was done on the patients diagnosed as subaortic stenosis at the Department of Pediatrics, Chonnam University Hospital from January 1989 to July 1999. The type of subaortic stenosis, age of onset and associated cardiovascular abnormalities were analyzed. The results were as follows: 1) Subaortic stenosis was found in 71 cases(male 39, female 32) among 3,406 patients with congenital heart disease(approximately 2.0 % of total patients with congenital heart disease), and was found in 57.7 % of total patients with aortic stenosis. There was no sexual differences. 2) Among 71 patients with subaortic stenosis, posteriorly deviated outlet septum was found in 35 cases, discrete fibrous or fibromuscular ridge in 23 cases, hypertrophic obstructive cardiomyopathy in 11 cases, and tumor in 2 cases. While the subaortic stenosis due to posterior deviation of outlet septum that was commonly diagnosed at the age less than 1 year, discrete fibrous or fibromuscular ridge was commonly found over 1 year of age. 3) Among 71 patients with subaortic stenosis, Most of the cases(90.2 %) were found to be associated with others; 48 cases were associated with ventricular septal defect, 23 cases with mitral valve abnormalities, 15 cases with coarctation of aorta, 15 cases with aortic valve abnormalities, 10 cases with interrupted aortic arch. 6 cases were detected after surgical closure of VSD, and 1 case after surgical correction of atrioventricular septal defect. Therefore, careful diagnostic evaluation is suggested for the detection of associated cardiovascular abnormalities in patients with subaortic stenosis, and also close follow-up examination of patients who underwent surgical correction of VSD and AVSD.