The Usefulness of the TAPSE/sPAP Ratio for Predicting Survival in Medically Treated Chronic Thromboembolic Pulmonary Hypertension

Objective: The ventriculoarterial uncoupling has been linked with unfavorable results as measured noninvasively by tricuspid annular plane systolic excursion divided by systolic pulmonary artery pressure (TAPSE/sPAP). However, its prognostic importance in chronic thromboembolic pulmonary hypertension (CTEPH) is limited. Thus, we determine the effect of the TAPSE/sPAP ratio on outcomes and predictors of all-cause mortality in these patients. Methods: We analyzed 56 subjects with medically treated CTEPH. Two-dimensional echocardiographic examination and right heart catheterization findings were recorded from the hospital database. Baseline New York Heart Association functional class (NYHA-FC), 6-min walk distance (6MWD), and brain natriuretic peptide (BNP) test results were recorded. Results: The median age was 65.5 years. Over a median follow-up time of 27 months, 29 (51.8%) patients died. BNP values were higher (P = 0.008), 6MWD values were lower (P = 0.004), and NHYA-FC (P = 0.0001) was worse in the non-survivor group. TAPSE (P = 0.0001) and TAPSE/sPAP ratio (P = 0.001) were significantly lower and pulmonary vascular resistance (PVR) was higher in the non-survivor group (P = 0.03). The best cut-off value for the TAPSE/ sPAP ratio for predicting mortality was 0.20 mm/mmHg and the survival rates were significantly lower in the TAPSE/sPAP ratio <= 0.20 group (log-rank P = 0.012). 6MWD (P = 0.005), NHYA-FC III-IV (P = 0.0001), TAPSE/sPAP ratio <= 0.20 (P = 0.017), PVR (P = 0.008), and TAPSE/sPAP ratio <= 0.20 combined with NYHA-FC III-IV (P = 0.0001) were significant determinants and TAPSE/sPAP ratio <= 0.20 combined with NYHA-FC III-IV was the only independent predictor of mortality (P = 0.003). Conclusion: Medically treated CTEPH patients with a TAPSE/sPAP ratio <= 0.20 had lower survival rates. TAPSE/sPAP ratio <= 0.20 combined with NYHA-FC III-IV was the independent predictor of poor prognosis.