Three-dimensional transesophageal echocardiography and cardiac MRI
visualization of an unusual etiology of left ventricular outflow tract
obstruction; in an adult patient with Atrioventricular Septal Defect
Abstract
A 54-year old woman with history of hypertension was admitted our
hospital with NYHA class 2-3 dyspnea. Fifteen years ago, she had primum
atrial septal defect repair, septal myectomy and anterior mitral leaflet
repair. Transthoracic echocardiography revealed a 112 mmHg gradient at
rest in the left ventricular outflow tract (LVOT), suggesting the
subaortic membrane. When transesophageal echocardiography was performed,
it was observed that there was no subaortic membrane, but tunnel-type
obstruction due to septal bulging in the left ventricular outflow tract.
It was understood that this obstruction also contributed to the
abnormally located papillary muscle, which is directly connected to the
anterior mitral leaflet. The patient was evaluated as partial type
Atrioventricular Septal Defect (AVSD) with a history of previous
operation, anomaly of the anatomy of LVOT and atrioventricular valves,
and other available findings, and the patient underwent mitral valve
replacement with septal myectomy. After the operation, the lvot gradient
decreased, the symptoms of the patient regressed and the patient was
followed up medically.