Dynamic outflow tract obstruction in congenitally corrected transposition of the great arteries

Abstract

Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease, constituting 0.5% of all congenital heart defects. The incidence of left ventricle (non-systemic ventricle) outflow tract obstruction ranges between 44 and 57%. Herein, we present the case of a 45 year old woman with CCTGA with progressively worsening dyspnea who had been referred for surgical correction of severe systemic ventricle (morphologic right ventricle) atrio-ventricular valve (tricuspid valve) regurgitation. Cardiac magnetic resonance imaging (CMR) and transesophageal imaging (TEE) demonstrated severe systemic ventricle (morphologic right ventricle) contractile dysfunction, as well as dynamic non-systemic ventricle (morphologic left ventricle) outflow tract obstruction due to systolic anterior motion (SAM) of the non-systemic ventricle (morphologic left ventricle) atrio-ventricular valve (mitral valve) with a large membranous ventricular septal aneurysm that protrudes into the outflow tract of the non-systemic ventricle (morphologic left ventricle). Ultimately, our patient was felt to be too high-risk for surgical correction and a course of medical therapy has been pursued.