Assessment of Right Ventricular Pressure in Chronic Thromboembolic Pulmonary Hypertension: Comparison of Diagnostic Modalities and Balloon Pulmonary Angioplasty Outcomes.

Background/Objectives:: Right ventricular (RV) pressure assessment is crucial in both the diagnosis and follow-up of patients with chronic thromboembolic pulmonary hypertension (CTEPH). While right heart catheterization (RHC) and pulmonary angiography (PA) are gold-standard invasive methods, transthoracic echocardiography (TTE) offers a safer and more accessible alternative. This study aimed to evaluate the reliability of echocardiographic RV pressure estimation compared to invasive techniques and to identify clinical predictors of response to balloon pulmonary angioplasty (BPA). Methods: In this prospective study, 17 patients with confirmed CTEPH underwent RV pressure assessment via TTE, RHC (Swan-Ganz catheterization), and PA within the same hospitalization period. BPA responders were defined based on clinical improvement and were compared to poor responders using pre- and post-treatment parameters. Results: A strong correlation was found between Swan-Ganz and PA-derived pressures (r = 0.96), with a slightly lower correlation between TTE and PA (r = 0.84), and the lowest between TTE and Swan-Ganz (r = 0.78). In the well-responding group, the 6 min walk distance (6MWD) increased by 60 ± 18 m, compared to 12 ± 10 m in poor responders (p < 0.01). NT-proBNP levels decreased by 40% in responders versus 10% in non-responders (p < 0.01). TAPSE improved significantly in responders (from 16.0 ± 2.0 mm to 19.5 ± 2.5 mm, p < 0.01), while RV basal diameter decreased by 15% (p < 0.05). No significant echocardiographic improvement was observed in poor responders. Conclusions: TTE provides a reliable estimate of RV pressure in CTEPH when standardized protocols are followed. NT-proBNP levels and RV size may serve as useful predictors of BPA response.