TAPSE/sPAP by echocardiography to detect elevated pulmonary vascular resistance> 4 WU in postcapillary pulmonary hypertension patients: insights from the French PH HF registry

Abstract Background Post-capillary pulmonary hypertension (pcPH) lacks effective treatment options. Patients with a PVR > 4 WU, known as combined pcPH (cpcPH), may benefit from investigational drugs like sotatercept. Identifying cpcPH patients suitable for vasodilation therapy in echocardiography labs is critical. Purpose To pinpoint an echocardiographic parameter capable of detecting cpcPH patients with a PVR above 4WU, addressing a common challenge in clinical practice. Methods In this study, 225 participants from the French PH-HF registry, all diagnosed with heart failure and a preserved ejection fraction, were examined. These patients underwent right heart catheterization and got ultrasound examinations within a 24-hour timeframe. The pulmonary vascular resistance were calculated using previously established methods, and data from standard echocardiography, including assessments of diastolic function, were gathered. Results 69 patients exhibited a pulmonary vascular resistance (PVR) greater than 4 WU, while 156 patients had a PVR ≤ 4 WU. Age averaged 69±12 years. Mean pulmonary artery pressure, wedge pressure, cardiac output, and pulmonary vascular resistance were 39±9 mm Hg, 22±4 mm Hg, 5.1±1.7 l/min, and 3.5±2.0 WU, respectively. Comparative analysis between patients with PVR ≤ 4 WU and those with PVR > 4 WU revealed similar ejection fraction (EF), left atrial volume index, and E/A ratio by echocardiography (p=0.97, p=0.69, p=0.43, respectively). However, patients with PVR > 4 WU showed elevated E/e’ (p=0.008), higher systolic pulmonary artery pressure (sPAP, p=0.001), but reduced myocardial S and e’ tissue Doppler velocities (p=0.001) and tricuspid annular plane systolic excursion (TAPSE) (p=10^-5). Notably, the relationship between TAPSE/sPAP and PVR > 4 was curvilinear and strong (p=0.001, FIG 1). Using ROC curve analysis, patients with TAPSE/sPAP < 0.38 mm/mmHg were identified to have PVR > 4 WU with a sensitivity and specificity of 68%. Conclusion Within the scope of postcapillary pulmonary hypertension, right ventricular arterial coupling is a simple ultrasound parameter potentially effective in identifying individuals exhbiting PVR > 4 WU with a good sensitivityFigure 1:PRV and coupling plotFigure 2:RV coupling ROC