5-Year prognostic value of the right ventricular strain-area loop in patients with pulmonary hypertension

Aims Patients with pre-capillary pulmonary hypertension (PH) show poor survival, often related to right ventricular (RV) dysfunction. In this study, we assessed the 5-year prognostic value of a novel echocardiographic measure that examines RV function through the temporal relation between RV strain (E) and area (i.e. RV epsilon-area loop) for all-cause mortality in PH patients. Methods and results Echocardiographic assessments were performed in 143 PH patients (confirmed by right heart catheterization) Transthoracic echocardiography was utilized to assess RV epsilon-area loop. Using receiver operating characteristic curve-derived cut-off values, we stratified patients in tow- vs. high-risk groups for alt-cause mortality. Kaplan-Meier survival curves and uni-/multivariable cox-regression models were used to assess RV epsilon-area loop's prognostic value (independent of established predictors: age, sex, N-terminal pro B-type natriuretic peptide, 6-min walking distance). During follow-up 45 (31%) patients died, who demonstrated lower systolic slope, peak epsilon, and late diastolic slope (all P<0.05) at baseline. Univariate cox-regression analyses identified early systolic slope, systolic slope, peak epsilon, early diastolic uncoupling, and early/late diastolic slope to predict all-cause mortality (all P <0.05), whilst peak epsilon possessed independent prognostic value (P<0.05). High RV loop-score (i.e. based on number of abnormal characteristics) showed poorer survival compared to low RV loop-score (Kaplan-Meier: P < 0.01). RV loop-score improved risk stratification in high-risk patients when added to established predictors. Conclusion Our data demonstrate the potential for RV epsilon-area loops to independently predict all-cause mortality in patients with pre-capillary PH. The non-invasive nature and simplicity of measuring the RV epsilon-area loop, support the potential clinical relevance of (repeated) echocardiography assessment of PH patients.