Background:
Right ventricular (RV) function is an important determinant of outcomes in pulmonary hypertension (PH) patients. Conventional indices of fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE), and RV tissue Doppler imaging myocardial performance index (RV TDI MPI) have been used as surrogates of RV function. RV ejection fraction (EF) from real time three-dimensional echocardiography (RT-3DE) has emerged as a quantitative evaluation of global RV function and has correlated well with cardiac magnetic resonance imaging. In this study, 3D RV EF was compared with conventional indices in the serial evaluation of RV function in pediatric PH patients to predict adverse events.
Methods:
Forty-eight pediatric PH patients (median age = 10 years (4 months - 27 years)) were evaluated serially (138 visits with median interval visit = 116 days (4 -368 days)) with RT-3DE to follow their ejection fraction (EF) and conventional indices from April, 2014 to May, 2015. Echocardiographic variables include measures of RV function: 3D RV EF, FAC, TAPSE, and RV TDI MPI. Adverse events included: initiation or intensification of intravenous vasodilator therapy, atrial septostomy, Pott’s shunt, or death. Receiver Operating Characteristics (ROC) analyses were performed to identify the best cut-offs in predicting adverse events in serial follow up of pediatric PH patients.
Results:
Patients were classified based on their World Health Classification (I = 16, II=16, III=11, IV=3). Two patients were not classified as they were too young. There were 13 adverse events. 3D RV EF was a good predictor of adverse events with highest area under curve (AUC) = 0.79, p<0.001(cut-off value of 38% = sensitivity 69%; specificity of 78%) compared to FAC has an AUC = 0.77, p<0.05 (cut-off value of 33% = sensitivity 63%; specificity of 78%). TAPSE and TV TDI MPI were not statistically significant (AUC = 0.54, p = 0.65; AUC 0.63, p = 0.09 respectively).
Conclusion:
3D RV EF is a good index in predicting adverse events and was better than FAC, TAPSE, and RV TDI MPI in predicting adverse events in serial follow up of pediatric PH patients. 3D RV EF can be used as a noninvasive tool in the serial evaluation of RV function in pediatric PH patients as it is easily obtained clinically.
Age-, Body Size-, and Sex-Specific Reference Values for Right Ventricular Volumes and Ejection Fraction by Three-Dimensional Echocardiography
