Sleep Disordered Breathing (SDB) and Chronic Thromboembolic Pulmonary Hypertension: the Effects of Pulmonary Endoarterectomy

Abstract

In patients with chronic thromboembolic PH (CTEPH), pulmonary endoarterectomy (PEA) provides effective relief from PH. We assess the pre- and post-operative prevalence of SDB in patients with CTEPH who had been submitted to PEA and the relationship between SDB and clinical and physiological factors. Cardiorespiratory recording was performed on the night before intervention and 3-months later in 50 patients (mean age 62.5±11.1 yrs) undergoing PEA. Patients were classified as central sleep apnea (CSA) if >70% of the events were central or as obstructive sleep apnea (OSA) if > 70% were obstructive. At pre-intervention, 14 patients (57% female) had No SDB, 26 (73% female) had OSA, and 10 (20% female) CSA. There were no differences in the history of venous thrombosis, atrial fibrillation, hypertension, diabetes, COPD and in the presence of oxygen therapy. Mean right atrial pressure (RAP) and mean pulmonary artery pressure (PAP) and TAPSE showed a trend toward a more compromised profile from NoSDB to OSA and CSA. RAP: 5.6±4.2 vs 6.7±4.3 vs 9.7±4.3 mmHg (p=0.07), PAP: 40±13 vs 47±12 vs 51±16 mmHg (p=0.11), TAPSE: 19±4 vs 16±3 vs 17±3 (p=0.06). Cardiac Index, PaO2 and PaCO2 were similar among the 3 groups. At post-intervention, the prevalence of SDB did not change: 12 patients had NoSDB, while 34 had OSA and 4 CSA. However, no trend was found in the relief from PH. PAP was 27±9 vs 25±7 vs 23±6 mmHg (p=0.73). Interestingly, 7 patients with previous CSA moved to the OSA group. Prevalence of SDB is high in patients with CTEPH even after resolution of PH. These data do not support the hypothesis that precapillary PH may trigger SBD, but rather suggest that SDB may be a causative factor leading to PH.