Right ventricular function in asymptomatic individuals with a systemic right ventricle

Background: In congenital heart defects where the morphologic right ventricle (RV) supports the systemic circulation, RV failure is common yet develops gradually. We hypothesized that patients who are asymptomatic may have unrecognized RV dysfunction. Methods: Conventional and Doppler tissue/strain echocardiography were performed on consecutive patients with asymptomatic systemic RV caused by congenitally corrected transposition of the great arteries (ccTGA) and on age-matched control subjects. RV index of myocardial performance was measured using conventional echocardiography. Longitudinal tissue velocities, strain rate, and strain of the basal RV free wall were measured using Doppler tissue/strain echocardiography and compared with nonsystemic RV of the control subjects. Results. Mean age was 39.5 +/- 14.6 (n = 13) and 36 +/- 24 (n = 10) years for ccTGA and control groups, respectively. Mean RV index of myocardial performance was higher in patients with ccTGA than in control subjects (0.66 +/- 0.25 vs 0.28 +/- 0.12, P < .001). Mean RV tissue displacement (10.8 +/- 4.5 vs 20.3 +/- 3.9 mm, P < .0001), peak systolic strain rate (-1.16 +/- 0.3 vs -2.23 +/- 0.9 s(-1), P = .005), and peak systolic strain (-17.3 +/- 8.0 vs -30.6 +/- 11.0%, P = .008) were significantly lower in patients with ccTGA compared with control subjects, respectively. Conclusion: Patients with asymptomatic ccTGA have quantifiable RV dysfunction by echocardiography.