The Prognostic Value of Right Ventricle–Pulmonary Artery Coupling for one- and three-year Survival in Patients with Precapillary Pulmonary Hypertension

Introduction. There is a growing interest in right ventricle (RV) function and RV–pulmonary artery (PA) coupling in patients with pulmonary hypertension (PH). While studies have shown correlation between TAPSE/PASP and pulmonary vascular resistance (PVR) in precapillary PH patients, the prognostic value of RV–PA coupling, as well as possible additional echocardiographic parameters representing RV function and coupling or uncoupling, remains underexplored. Objectives. The objective of this study was to assess the prognostic value of 2D echocardiographic parameters focusing on the right heart. We aimed to determine the predictive value of RV function and RV– PA coupling at baseline for one- and three-year survival in patients with precapillary PH. Materials and Methods. In this retrospective study 55 patients diagnosed with precapillary PH (groups 1 and 4) were included. The median age at the time of diagnosis was 57.5 years. Among them, 16 were male (29.1 %), and the remaining 70.9% were female. The median of mean pulmonary arterial pressure (mPAP) was 43 mmHg, pulmonary capillary wedge pressure 10.0 [6.0-11.0] mmHg. Specific treatment for PH did not differ between the survivor and non-survivor groups. Baseline 2D echocardiographic parameters were analyzed. Statistical analysis was performed to identify predictive parameters. Results. One-year survival was 78.2%, three-year survival was 50.9%. Survival rates did not differ between gender groups. In one-year survival analysis, a tendency towards lower RV fractional area change (FAC) in the non-survivor group was observed; however, the difference was not statistically significant (29.3 [24.2-34.3] % vs. 22.8 [21.0-30.9] %, p=0.087). A similar trend was observed for RV free wall longitudinal strain (FWLS), as baseline values were lower in the one-year non-survivor group compared to the survivor group (-12.9 [-10.2- (-18.2)] % vs. -10.9 [-9.28-(-12.3)] %, p=0.051). At three-year follow-up, several parameters demonstrated significant differences between the analysed groups. Tricuspid annular plane systolic excursion (TAPSE) was higher in the survivor group (17.0 [16.0–19.0] mm) compared to the non-survivor group (15.0 [12.8–17.0] mm), p=0.019. TAPSE/pulmonary artery systolic pressure(PASP) ratio was also higher among survivors (0.23 [0.15-0.37] mm/mmHg) versus non-survivors (0.16 [0.13-0.21] mm/mmHg), p=0.031. In addition, the S’/ PASP ratio was higher in the survivor group (0.12 [0.089-0.21] vs 0.10 [0.070-0.13], p=0.046). Conclusions. Right ventricle FWLS and FAC at baseline could have a predictive value in association with one-year mortality; however, stronger evidential support is still needed. RV-PA uncoupling (TAPSE/ PASP, S’/PASP) as well as reduced RV longitudinal function (TAPSE, S’) at baseline indicate an unfavorable three-year prognosis.