Obstructive sleep apnea and echocardiographic indicators of elevated pulmonary hypertension probability after pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension

Abstract

Study objectives: We previously demonstrated that 80% of patients with chronic thromboembolic pulmonary hypertension (CTEPH) exhibit sleep-related breathing disorders (SBDs), primarily obstructive sleep apnea (OSA), followed by isolated sleep-related hypoxemia (ISRH). In this follow-up study, we aimed to assess the distribution of SBDs and predictors of echocardiography-based residual pulmonary hypertension (PH) risk after pulmonary endarterectomy (PEA) in the same cohort. Methods: Overnight polysomnography and echocardiography were performed in 24 CTEPH patients approximately 112 +/- 65 days after PEA. Residual PH risk was defined as peak tricuspid regurgitation velocity (TRV) > 2.8 m/s and systolic pulmonary artery pressure (SPAP) >= 30 mmHg. Results: In the overall cohort, PEA significantly reduced TRV (from 3.7 +/- 0.9 to 2.5 +/- 0.9 m/s, p < 0.001) and SPAP (58.3 +/- 26.9 to 29.8 +/- 17.7 mmHg, p < 0.001). Among six patients with preoperative ISRH, two improved, while four developed OSA postoperatively. Of the 16 patients with preoperative OSA, 14 remained in the same category after surgery. Residual PH risk was observed in 13 patients (54.2%), all of whom had OSA, while no residual PH risk was detected in patients without SBDs (p = 0.003). In multivariate logistic regression, postoperative apnea-hypopnea index was independently associated with echo-based residual PH risk (odds ratio 1.19; 95% CI 1.02-1.38; p = 0.025), after adjustment for age, sex, body mass index, and baseline mean pulmonary arterial pressure. Conclusions: PEA improves pulmonary hemodynamics and resolves ISRH in some patients with CTEPH. However, residual PH risk remains frequent and is independently associated with OSA severity. These findings emphasize the importance of systematic screening, early diagnosis, and management of OSA to potentially mitigate residual PH risk and improve postoperative outcomes in CTEPH.