Forgotten Right Ventricle in Pediatric Dilated Cardiomyopathy

Abstract

To evaluate the right ventricular (RV) function in relation to that of the left ventricle (LV) in patients with dilated cardiomyopathy (DCM). Echocardiographic examination was done using tissue Doppler imaging (TDI) and two-dimensional speckle tracking echocardiography (2D-STE) for 32 pediatric patients with DCM comparing them to another 32 normal matched controls. The global longitudinal strain (GLS) derived from 2D-STE was used to reflect the LV systolic function. Tricuspid annular plan systolic excursion (TAPSE) and the following RV TDI derived indexes: peak systolic velocity (S'), peak early diastolic velocity E', peak late diastolic velocity A', isovolumic acceleration (IVA) and myocardial performance index (MPI) were measured. RV had significant systolic and diastolic dysfunction; TAPSE, S' velocity, IVA, peak early diastolic velocity (E') and peak early diastolic velocity/peak late diastolic velocity (E'/A') ratio were significantly decreased while MPI was significantly prolonged compared to controls. Moreover, TAPSE, S', IVA, E', E'/A' and RV MPI were significantly correlated to LV GLS. For prediction of LV dysfunction among patients, the area under the receiver operating characteristic curve was 0.98 for RV MPI, 0.906 for RV IVA. For identifying severe LV dysfunction; RV MPI > 0.29 had 100% sensitivity and 93.7% specificity, while the RV IVA ≤ 3 had 84.4% sensitivity and 90.6% specificity. In pediatric patients with DCM the RV systolic and diastolic functions are affected beside the LV dysfunction. Non-conventional echocardiographic evaluation of RV function is recommended in among this cohort.

Keywords: 2D-speckle tracking; Dilated cardiomyopathy; Isovolumic acceleration; Right ventricle; Tissue Doppler imaging.