Abstract 4144793: Pulmonary Thromboendarterectomy in a Developing Country: Clinical and Hemodynamic Outcomes and Predictors of Hospital Mortality

Introduction: Pulmonary thromboendarterectomy (PTE) is the definitive therapy for chronic thromboembolic pulmonary hypertension (CTEPH). Outcomes are highly dependent on local expertise and volume. We aimed to describe clinical and hemodynamic outcomes of patients with CTEPH undergoing PTE in a developing country, and to assess predictors of mortality. Methods: Single-center observational study, with prospective data collection of consecutive patients with symptomatic CTEPH who underwent PTE in a high-volume PH center in Brazil. Clinical and demographic variables were systematically collected by the Pneumology team. Hemodynamic data were collected in the right heart catheterization, prior to PTA, and in the post-procedural Swan-Ganz monitoring. Echocardiography (echo) was performed pre procedure and in the earliest available follow-up. Hemodynamic variables of interest were invasive mean pulmonary artery mean pressure (PAPm), cardiac index (CI) and pulmonary vascular resistance (PVR), and systolic pulmonary artery pressure (SPAP) on echo, compared pre and post-surgery. The outcome of interest was in-hospital mortality, and significant predictors in bivariate analysis were included in multivariate regression models. Results: At total 64 patients underwent CTEPH, 37 (58%) women, mean age of 51±14 (range 23-78) years. All but 13 patients had documented acute pulmonary embolism, and 13 (20%) had deep vein thrombosis. Functional class was NYHA 3 or 4 in 38 (59%) cases, and mean NT-ProBNP was 1182±1642pg/ml. Compared to baseline, PAPm (51.9 ± 17.0 vs. 28.5 ± 8,6 mmHg, p<0.001), PVR (11.5 ± 5.3 vs. 4.7 ± 3.7 UWood, p<0.001) and SPAP (87.4 ± 22.1 vs. 57.5 ± 18.5 mmHg, p<0.001) decreased significantly in the post-procedural evaluation, with a parallel increase in CI (2.4±1.0 vs. 3.0±0.7 L/min/m 2 , p=0.039). In the late port-surgical echo, SPAP remained similarly low (54.1 ± 22.1 mmHg, p=0.46). In-hospital mortality occurred in 11 (17.2%) individuals, and the most frequent non-fatal complication was infection (N=5). Patients who died were more frequently women, had higher NT-ProBNP levels and higher post-operative PVR. The only independent predictor of mortality among the available variables was female sex: OR=9.6 (95% CI 1.5 – 80.7), p=0.03, in the age-adjusted model. Conclusion: PTE resulted in significant and long-standing hemodynamic improvement among patients with CTEPH. The growing multidisciplinary experience tend to improve hard clinical outcomes.