Right ventricular free-wall longitudinal speckle tracking strain in patients with pulmonary arterial hypertension under specific treatment

Background Right ventricular (RV) dysfunction is a major determinant of outcomes in patients with pulmonary arterial hypertension (PAH), although the optimal measure of RV function is poorly defined. We evaluated the utility of RV free-wall speckle tracking strain as an assessment tool for RV function in patients with PAH who are already under specific treatment compared with conventional echocardiographic parameters and investigated the relationship of RV free-wall strain with clinical hemodynamic parameters of RV performance. Methods Right ventricular free-wall strain was evaluated in 92 patients (Group-1 and Group-4 pulmonary hypertension) who were on PAH-specific treatment for at least 3 months. Right atrial (RA) area, RV FAC, TAPSE, tricuspid S, functional class, 6-minute walking distance, and NT-proBNP were studied. The mean duration of follow-up was 222 +/- 133 days. Results All patients were under PAH-specific treatment, and mean RV free-wall strain was -13.16 +/- 6.3%. RV free-wall strain correlated well with functional class (r=.312, P=.01), NT-proBNP (r=.423, P=.0001), RA area (r=.427, P=.0001), FAC (r=-.637, P=.0001), TAPSE (r=-.524, P=.0001), tricuspid S (r=-.450, P=.0001), 6-minute walking distance (r=-.333, P=.002). RV free-wall strain significantly correlated with all follow-up adverse events, death, and clinical right heart failure (RHF) (P=.04, P=.03, P=.02, respectively). According to the receiver operator characteristic analysis, the cutoff value for RV free-wall strain for the development of clinical RHF was -12.5% (sensitivity: 71%, specificity: 67%) and for all cardiovascular adverse events (death included) was -12.5% (sensitivity: 54%, specificity: 64%). Conclusion Assessment of RV free-wall strain is a feasible, easy-to-perform method and may be used as a predictor of RHF, clinical deterioration, and mortality in patients already under PAH-specific treatment.