Late gadolinium enhancement cardiovascular magnetic resonance of the systemic right ventricle in adults with previous atrial redirection surgery for transposition of the great arteries

Background-Patients treated for transposition of the great arteries by atrial redirection surgery have a right ventricle (RV) that sustains systemic pressures long term. Late RV dysfunction occurs in these patients; the reasons for this are unclear, but myocardial fibrosis may be important. Myocardial fibrosis can be visualized by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR). We hypothesized that LGE would be present in the systemic RV and relate to adverse clinical features. Methods and Results-We performed CMR on 36 consecutive adult patients (mean age, 27 years) after atrial redirection surgery for transposition of the great arteries. Late gadolinium RV enhancement was seen in 22 patients (61%) with various patterns. Patients with RV LGE were older (30 versus 22 years; P<0.001) and had increased RV end-systolic volume index (43 versus 35 mL/m²; P=0.03), decreased RV ejection fraction (57% versus 62%; P=0.02), increased QRS duration (108 versus 97 ms; P=0.01), and increased QT dispersion (93 versus 71 ms; P=0.002). The extent of LGE correlated with age (r=0.59, P<0.001) and QRS duration (r=0.67, P<0.001) and inversely with RV ejection fraction (r=-0.76, P<0.001). The incidence of documented arrhythmia and/or syncope (10 of 36) was significantly higher in the late gadolinium-positive group (9/22 versus 1/14; P=0.03). Conclusions-LGE CMR suggestive of myocardial fibrosis occurs in the systemic RV of patients after atrial redirection, surgery. The extent of LGE correlates with age, ventricular dysfunction, electrophysiological parameters, and clinical events, suggesting prognostic importance that merits further investigation.