Impact of Pulmonary Endarterectomy on Sleep-Related Breathing Disorders in CTEPH: The IPES Trial

Pulmonary hypertension (PH) has three main types, pre-capillary PH, post-capillary PH, and combined pre-capillary and post-capillary PH, and it is based on mean pulmonary arterial pressure (PAP) \> 20 mmHg measured with a right heart catheterization (RHC). Chronic thromboembolic pulmonary hypertension (CTEPH) is mainly defined as a pre-capillary PH and classed as a Group IV PH. It was reported that 0.1-9.1% of individuals with pulmonary embolism develop CTEPH within two years after the initial diagnosis, and CTEPH is the only PH category that has a chance of being cured, mainly by pulmonary endarterectomy. Sleep-related breathing disorders (SRBD) are defined as obstructive sleep apnea (OSA) disorders, central sleep apnea (CSA) syndromes, sleep-related hypoventilation disorders, and sleep-related hypoxemia. An SRBD may also lead to an increase in PAP primarily during sleep and cause nocturnal hypoxemia. Although SRBDs were reported in patients with pre-capillary PH, most of the studies included patients with idiopathic PAH. Although the cause-and-effect relationship between pre-capillary PH and SRBDs is uncertain, it is known that mPAP may increase during sleep in patients with OSA . Less is known regarding the occurrence of SRBDs in CTEPH. Previously a few study showed relationship between SRBDs an CTEPH as the main type was OSA. Most of the studies evaluated preoperative occurance and incidance of SRBDs in CTEPH. Only one study performed post operative SRBD on a cardiorespiratory device was conducted the night before and one month after elective pulmonary endarterectomy. In our previous study we showed that severe nocturnal hypoxemia (NH) is highly prevelant in preoperative CTEPH patients and the most common two types of SRBD are OSA and isolated sleep related hypoxemia (ISRH) and age, mPAP and AHI are independent determinants of severe NH. (J. Clin. Med. 2023, 12, 4639 https://doi.org/10.3390/jcm12144639) In this present study we aimed to investigate occurren