Biventricular interaction and aortic function in adult patients with repaired tetralogy of Fallot: a two-dimensional-three-dimensional speckle-tracking echocardiographic study.

Abstract

In patients late after correction of tetralogy of Fallot (TOF), the combined effects of pre-operative hypertrophy and hypoxia, ventricular interdependence, acquired post-operative lesions such as pulmonary or aortic regurgitation, and congenital vasculopathy may result in impaired right ventricular (RV) and left ventricular (LV) function. The aim of the present study was to investigate the interventricular interactions in repaired TOF (rTOF) and the impact of aortic function on biventricular performance using two-dimensional (2D-STE) and three-dimensional speckle-tracking echocardiography (3D-STE). Twenty-five adult patients with rTOF and 25 age- and gender-matched healthy controls were studied. LV and RV volumes were determined by 3D-STE and cardiac magnetic resonance. LV and RV longitudinal strains (LVLS and RVLS) and LV and RV area strains (LVAS and RVAS) and LV twist/rotation were calculated by 3D-STE. Ascending aorta circumferential strain (AAo-CS) was obtained using 2D-STE. LV 3D-STE parameters were decreased in rTOF patients compared with controls even in patients with normal ejection fraction. AAo-CS was decreased (6.7 ± 1.9 vs. 10.1 ± 2.6, P = 0.003) in rTOF patients compared with controls even in the presence of normal aortic dimensions and correlated with AAo diameter (r = -0.69, P = 0.0001), LV twist (r = 0.54, P = 0.004), LVAS (r = -0.56, P = 0.003), and RVLS (r = -0.39, P = 0.036). LVAS and AAo-CS were associated with disease severity (peak oxygen consumption and arrhythmia occurrence). Significant improvement in global χ 2 value was noted with RV 3D-STE parameters + LVAS + AAo-CS compared with RV dysfunction alone for detecting exercise capacity impairment (from 77.1 to 84.4 to 91.2, P = 0.003). Speckle-tracking echocardiography revealed subtle LV and AAo dysfunction in adults with rTOF. A correlation was observed between LV and RV strain changes and between AAo strain impairment and LV/RV dysfunction. LV and AAo changes had an incremental value in evaluating disease severity.