Discrete subaortic stenosis in an adult Nigerian: a case report

Cases of discrete subaortic stenosis are rare in adults. To our knowledge, no case has been reported in Nigerian literature. Cases are thus likely to be missed or wrongly managed.

To present a case of discrete membranous subaortic stenosis in an adult Nigerian with a view to creating awareness of the existence of this entity in our milieu.

The patient a 46-year-old Nigerian presented with symptoms of angina pectoris and near syncope. Transthoracic 2-Dimensional / M-mode echocardiography demonstrated thickened and calcific aortic valves and laboratory investigations showed that he also had artherogenic dyslipidaemia. He was initially managed as a case of severe valvular aortic stenosis of rheumatic origin with associated dyslipidaemia and was referred for further evaluation and management abroad.

On further assessment at the referral centre, the diagnosis was reviewed to subaortic stenosis with severe left ventricular outflow tract obstruction (LVOTO) arising from a fibro muscular subaortic membrane after a repeat 2-D/M-mode and Doppler echocardiography. Coronary angiography showed normal coronaries. He had excision of the membrane with marked reduction in gradient across the left ventricular outflow tract. He has remained symptom free and stable thereafter.

Discrete membranous subaortic stenosis though rare in adults should be suspected in patients with clinical features of valvular aortic stenosis. Doppler echocardiography is thus mandatory in the evaluation of these patients.