Congenitally corrected transposition of the great arteries presenting in a nonagenarian.

An 82-year-old woman presented with recurrent syncope. Clinically, she had a slow rising pulse, right parasternal heave, and an ejection systolic murmur loudest at the right sternal edge with a quiet pansystolic murmur at the apex. ECG demonstrated prolonged PR interval and extreme leftward axis. Transthoracic and transesophageal echocardiography revealed atrioventricular and ventriculoarterial discordance, suggesting congenitally corrected transposition of the great arteries (ccTGA). The systemic right ventricle (RV) was hypertrophied and mildly dilated with normal systolic function, but there was severe subvalvular stenosis with a peak velocity of 4.5 m/s (Figures 1 and 2). The aortic valve was trileaflet and anterior to the pulmonary valve, and there was mild left atrioventricular valve regurgitation. Cardiac magnetic resonance imaging confirmed a systemic RV with marked hypertrophy (RV mass, 112 g; mass index, 72 g/m) but normal volumes and function (RV end-diastolic volume, 95 mL; RV end-systolic volume, 27 mL; ejection fraction, 0.72). There was minimal systemic atrioventricular valve regurgitation. There was a muscle band across the systemic RV outflow tract, causing dynamic obstruction (Figures 3 and 4). The subpulmonary left ventricle was thin with normal volumes and function without obstruction of the outflow tract or main or branch pulmonary arteries. Coronary angiography confirmed a dominant left coronary artery with a posterior origin and a small right coronary artery. Right heart catheterization confirmed normal pulmonary artery pressures. The patient underwent surgery to relieve the RV outflow tract obstruction. At operation, there was a tunnel-like outflow tract obstruction. The myocardium was resected to allow passage of a Heger dilator into the morphological RV, but the aortic valve was not modified. Histology of the resected myocardium confirmed myocyte hypertrophy with fibrosis and marked endocardial thickening. Postoperative recovery was rapid and uneventful, with discharge from hospital on day 6. ccTGA is uncommon, accounting for 1% of patients born with congenital heart disease, and only 1% of these patients have uncomplicated ccTGA (without associated abnormalities such as pulmonary stenosis, ventricular septal defect, or an Ebstein-like tricuspid valve).1 ccTGA may frequently present in adulthood. In 1 study, 66% of patients with ccTGA presented in adulthood, with 17% of those patients being 60 years of age.2 Morbidity and mortality in this group are due predominantly to systemic atrioventricular valve regurgitation and systemic RV failure. In 1 multicenter study, 25% of patients with uncomplicated ccTGA had developed significant RV dysfunction by 45 years of age.3 However, very late presentation of ccTGA, in the eighth decade of life, is unique and is notable for the presence of severe systemic ventricle outflow tract obstruction but with preserved systemic ventricular function without major atrioventricular valve regurgitation.