Right ventricular global longitudinal strain predicts survival in patients with pulmonary hypertension receiving specific vasodilator therapy

Abstract

In patients (pts) with pulmonary hypertension (PH) different right ventricular (RV) function parameters predict outcome. Data regarding the prognostic value of averaged 6-segments RV longitudinal strain (RV-GLS) in PH pts are scarce. To assess the predictive value of 6-segments RV-GLS in PH pts receiving vasodilator therapy. Forty-seven pts (40 ± 15 years, 36 women) with PH treated with either bosentan, sildenafil, or both and 33 controls with similar age and gender (40 ± 11 years, 21 women) were studied. Clinical parameters and biologic (B-type natriuretic peptide, BNP), invasive and echocardiographic parameters of RV function (TAPSE, TDI-derived free-RV wall S- and e’-wave, RV fractional area change (FAC), Tei index, I/H, RV isovolumic acceleration-IVA) were assessed. 6-segments RV-GLS was measured from the apical 4-chamber view by STE. PH pts were followed-up for 23 months (2–49). An endpoint of cardiac death was defined. PH pts had larger right chambers size, PA size and pressures, impaired RV function than controls (all P < 0.001), including RV-GLS (−14.0 ± 4.8% vs. −23.3 ± 2.7%, P < 0.001). During follow-up, 8 pts died. At univariable analysis, predictors of death were: TAPSE (15 ± 3 mm in deceased pts vs. 18 ± 3 mm in surviving pts, P = 0.011), RV-S (9.1 ± 2.1 cm/s vs. 11.5 ± 1.9 cm/s, P = 0.002), FAC (25 ± 9% vs. 36 ± 8%, P = 0.001), RV-GLS (−9.6 ± 4.2% vs. −14.9 ± 4.5%, P = 0.003), IVA (0.16 ± 0.07 cm/s 2 vs. 0.24 ± 0.10 cm/s 2 , P = 0.041) and BNP levels (lnBNP, 5.8 ± 1.0 vs. 4.7 ± 1.5, P = 0.05). ROC curve analysis showed that RV-GLS had the highest predictive value for cardiac death (AUC 0.82, P = 0.005). Cutoff value for RV-GLS derived from ROC curve analysis was used to construct Kaplan-Meier survival curves. A value of −13.2% for RV-GLS predicted cardiac death with 87% sensitivity and 62% specificity. In PH pts, RV function parameters have prognostic value. Six-segments RV-GLS emerged as the strongest predictor of cardiac death with a cutoff value of −13.2% in this setting.