Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension improves sleep-disordered breathing

Rationale: Chronic thromboembolic pulmonary hypertension (CTEPH), a major vessel obstructive pulmonary vascular disease may be comorbid with sleep-disordered breathing (SDB). Multiple studies have reports on PH and SDB, but limited data are available in CTEPH. In this prospective study, we sought to determine the prevalence of SDB in subjects with CTEPH and examined the effects of successful balloon pulmonary angioplasty (BPA). Methods: 44 consecutive patients with CTEPH underwent treatment-naïve and post-BPA polygraphy (nasal pressure sensor, thermistor, thoracoabdominal excursions, and a pulse oximeter) and hemodynamic and echocardiographic assessments. We used an AHI ≥5/hour as the threshold to define SDB. Results: Before BPA 32 subjects (73%) had SDB, 24 (55%) with obstructive sleep apnea (OSA; AHI= 25), and 8 (18%) with central sleep apnea (CSA; AHI= 38). OSA was associated with male gender, obesity, and fluid-shifts, whereas CSA was associated with right ventricular end-diastolic diameter. PVR changed from 7.9 to 4.9 wood units during treatment with BPA. In OSA patients, AHI decreased from 25 to 18 (p= 0.045) and ODI from 28 to 21 (p= 0.011). In CSA patients, AHI and ODI decreased from 38 to 19 (p= 0.007) and 46 to 27 (p= 0.012), respectively. Along with the improvement in SDB, nocturnal desaturation decreased (time-below-90% from 50% to 41% of time-in-bed, p= 0.008). Conclusion: In CTEPH, there is a high prevalence of OSA and CSA. Notably, we found that BPA significantly improved SDB breathing and associated nocturnal desaturations. Future studies will show if effective treatment of SDB will improve central hemodynamics, morbidity and mortality in CTEPH.