{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,23]],"date-time":"2026-08-23T02:19:18Z","timestamp":1787451558245,"version":"build-2736575974"},"reference-count":30,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,10,25]],"date-time":"2023-10-25T00:00:00Z","timestamp":1698192000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCDD"],"abstract":"<jats:p>Background: Pulmonary endarterectomy (PEA) is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension (CTEPH) with accessible lesions. Breathing pure oxygen (hyperoxia) during right heart catheterization (RHC) allows for the calculation of the right-to-left shunt fraction (Qs\/Qt). In the absence of intracardiac shunt, Qs\/Qt can be used as a marker of ventilation\u2013perfusion mismatch in patients with CTEPH. This study involved investigating Qs\/Qt after PEA and its relation to other disease-specific outcomes. Study design and Methods: This study is a retrospective study that focuses on patients with operable CTEPH who had Qs\/Qt assessment during RHC before and 1 year after PEA. Additionally, 6 min walking distance (6MWD), WHO functional class (WHO-FC), and NT-proBNP were assessed to calculate a four-strata risk score. Results: Overall, 16 patients (6 females) with a median age of 66 years (quartiles 55; 74) were included. After PEA, an improvement in mean pulmonary artery pressure (38 [32; 41] to 24 [18; 28] mmHg), pulmonary vascular resistance (5.7 [4.0; 6.8] to 2.5 [1.4; 3.8] WU), oxygen saturation (92 [88; 93]% to 94 [93; 95]%), WHO-FC, and risk score was observed (all p &lt; 0.05). No improvement in median Qs\/Qt could be detected (13.7 [10.0; 17.5]% to 13.0 [11.2; 15.6]%, p = 0.679). A total of 7 patients with improved Qs\/Qt had a significant reduction in risk score compared to those without improved Qs\/Qt. Conclusion: PEA did not alter Qs\/Qt assessed after 1 year in operable CTEPH despite an improvement in hemodynamics and risk score, potentially indicating a persistent microvasculopathy. In patients whose shunt fraction improved with PEA, the reduced shunt was associated with an improvement in risk score.<\/jats:p>","DOI":"10.3390\/jcdd10110442","type":"journal-article","created":{"date-parts":[[2023,10,25]],"date-time":"2023-10-25T04:14:47Z","timestamp":1698207287000},"page":"442","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Change in Right-to-Left Shunt Fraction in Patients with Chronic Thromboembolic Pulmonary Hypertension after Pulmonary Endarterectomy"],"prefix":"10.3390","volume":"10","author":[{"given":"Lena","family":"Reimann","sequence":"first","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Mayer","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon Raphael","family":"Schneider","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8840-981X","authenticated-orcid":false,"given":"Esther I.","family":"Schwarz","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julian","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7431-1643","authenticated-orcid":false,"given":"Anna","family":"Titz","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8518-5029","authenticated-orcid":false,"given":"Michael","family":"Furian","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8019-7429","authenticated-orcid":false,"given":"Arcangelo F.","family":"Carta","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harry","family":"Etienne","sequence":"additional","affiliation":[{"name":"Department of Thoracic Surgery, University Hospital Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bianca","family":"Battilana","sequence":"additional","affiliation":[{"name":"Department of Thoracic Surgery, University Hospital Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phanie","family":"Saxer","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"},{"name":"Department of Health, Eastern Switzerland University of Applied Sciences, 9001 St. Gallen, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Pfammatter","sequence":"additional","affiliation":[{"name":"Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3295-6619","authenticated-orcid":false,"given":"Thomas","family":"Frauenfelder","sequence":"additional","affiliation":[{"name":"Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5900-9040","authenticated-orcid":false,"given":"Isabelle","family":"Opitz","sequence":"additional","affiliation":[{"name":"Department of Thoracic Surgery, University Hospital Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5250-5022","authenticated-orcid":false,"given":"Silvia","family":"Ulrich","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mona","family":"Lichtblau","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3618","DOI":"10.1093\/eurheartj\/ehac237","article-title":"2022 ESC\/ERS Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension","volume":"43","author":"Humbert","year":"2022","journal-title":"Eur. 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