Biventricular systolic function and mass studied with MR imaging in children with pulmonary regurgitation after repair for tetralogy of Fallot.

Abstract

To study biventricular systolic function and mass of the heart in young patients with residual pulmonary regurgitation who had undergone surgical correction of tetralogy of Fallot. Transverse gradient-echo magnetic resonance (MR) images covering both ventricles were obtained in 19 patients who had undergone corrective surgery for tetralogy of Fallot at the age of 1.5 years +/- 1 and in 12 age-matched control subjects. In addition, MR velocity maps of the pulmonary artery were obtained. Biventricular volumes, ejection fraction and myocardial mass, and pulmonary flow volumes were measured. Exercise tests were performed in 17 patients. The right ventricular ejection fraction was lower (P < .001) and the right ventricular mass was higher (P < .0005) in patients than in control subjects; the left ventricular ejection fraction was lower (P < .0005) in patients and correlated statistically significantly with pulmonary regurgitation (r = -.68; P < .005). Exercise performance inversely correlated with pulmonary regurgitation (tau = -0.5; P = .01). In children who undergo early surgical repair of tetralogy of Fallot, residual pulmonary regurgitation correlates with biventricular systolic dysfunction and diminished exercise capacity. Despite successful surgical correction, right ventricular hypertrophy may persist.