Joining efforts for the non-invasive evaluation in pulmonary hypertension: TAPSE/sPAP ratio

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Pulmonary hypertension remains an important challenge given its still elevated mortality rate and its complex clinical management, especially when it comes to risk stratification and imaging evaluation. In this respect, TAPSE/sPAP ratio obtained by echo is a surrogate of PA-RV coupling and has been suggested as a complementary approach to PH diagnosis and risk stratification. However, cut-offs for this ratio are yet to be clarified as recent guidelines refer a cut-off of 0,55, whilst other papers point that a lower cut-off of 0,35 could better estimate risk and prognosis. Purpose To analyse TAPSE/sPAP ratio impact in our population and to define an ideal cut-off to best correlate it with invasive hemodynamics and prognosis. Methods Single center retrospective study of patients with precapillary pulmonary hypertension who underwent right heart catheterization (RHC) and echocardiography within a time frame of 2 months. Clinical, laboratorial, echo and cath data were collected and statistical analysis was performed using Chi-square test, Mann-Whitney test, as well as ROC curve analysis and Kaplan-Meier analysis of survival. Results We analysed 79 patients (66% female, mean age 58,06 +- 15,3) with pre-capillary pulmonary hypertension – 53% had group 1 PH and 47% group 4 PH – followed during a mean period of 3,6 ±2,8years. Most patients were under specific therapy (93%), mostly with PDE5 inhibitors and endothelin receptor antagonists. According to guidelines, echo derived TAPSE/sPAP ratio of 0,55 was used and it correlated with hemodynamic parameters, namely mPAP (p = 0,005), RAP (p = 0,007), cardiac output (p = 0,007) and cardiac index (p = 0,045) and pulmonary vascular resistance (p = 0,01). However, a ratio<0,55 was not ideal to predict prognosis as it failed to show correlation with COMPERA score in follow-up (p = 0,69), clinical events (p = 0,31), progression to triple therapy or death (p = 0,45). Pts were alternatively divided into tertiles with ratios of <0,29, 0,30–0,58 and >0,59. These cut-offs showed a better positive correlation with COMPERA on follow-up (p = 0,05) and death. Kaplan-Meier curve analysis showed a clear separation of the three groups with these values. ROC curve analysis revealed that a cut-off of 0,39 had the best sensitivity and specificity to estimate clinical events (figure 1 and 2). Conclusion TAPSE/sPAP ratio showed a good correlation with hemodynamic parameters in pts with precapillary pulmonary hypertension. Notwithstanding, a cut-off of 0,39 showed positive correlation with survival and prognosis.