{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T14:45:51Z","timestamp":1790779551719,"version":"4.1.0"},"reference-count":45,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T00:00:00Z","timestamp":1626912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001711","name":"Schweizerischer Nationalfonds zur F\u00f6rderung der Wissenschaftlichen Forschung","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001711","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"<jats:p><jats:bold>Aims:<\/jats:bold> To test the acute hemodynamic effect of acetazolamide in patients with pulmonary hypertension (PH) under ambient air and hypoxia.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> Patients with pulmonary arterial or chronic thromboembolic PH (PAH\/CTEPH) undergoing right heart catheterization were included in this randomized, placebo-controlled, double-blinded, crossover trial. The main outcome, pulmonary vascular resistance (PVR), further hemodynamics, blood- and cerebral oxygenation were measured 1 h after intravenous administration of 500 mg acetazolamide or placebo-saline on ambient air (normoxia) and at the end of breathing hypoxic gas (F<jats:sub>I<\/jats:sub>O<jats:sub>2<\/jats:sub> 0.15, hypoxia) for 15 min.<\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> 24 PH-patients, 71% men, mean \u00b1 SD age 59 \u00b1 14 years, BMI 28 \u00b1 5 kg\/m<jats:sup>2<\/jats:sup>, PVR 4.7 \u00b1 2.1 WU participated. Mean PVR after acetazolamide vs. placebo was 5.5 \u00b1 3.0 vs. 5.3 \u00b1 3.0 WU; mean difference (95% CI) 0.2 (\u22120.2\u20130.6, <jats:italic>p<\/jats:italic> = 0.341). Heart rate was higher after acetazolamide (79 \u00b1 12 vs. 77 \u00b1 11 bpm, <jats:italic>p<\/jats:italic> = 0.026), pH was lower (7.40 \u00b1 0.02 vs. 7.42 \u00b1 0.03, <jats:italic>p<\/jats:italic> = 0.002) but PaCO<jats:sub>2<\/jats:sub> and PaO<jats:sub>2<\/jats:sub> remained unchanged while cerebral tissue oxygenation increased (71 \u00b1 6 vs. 69 \u00b1 6%, <jats:italic>p<\/jats:italic> = 0.017). In acute hypoxia, acetazolamide decreased PVR by 0.4 WU (0.0\u20130.9, <jats:italic>p<\/jats:italic> = 0.046) while PaO<jats:sub>2<\/jats:sub> and PaCO<jats:sub>2<\/jats:sub> were not changed. No adverse effects occurred.<\/jats:p><jats:p><jats:bold>Conclusions:<\/jats:bold> In patients with PAH\/CTEPH, i.v. acetazolamide did not change pulmonary hemodynamics compared to placebo after 1 hour in normoxia but it reduced PVR after subsequent acute exposure to hypoxia. Our findings in normoxia do not suggest a direct acute pulmonary vasodilator effect of acetazolamide. The reduction of PVR during hypoxia requires further corroboration. Whether acetazolamide improves PH when given over a prolonged period by stimulating ventilation, increasing oxygenation, and\/or altering vascular inflammation and remodeling remains to be investigated.<\/jats:p>","DOI":"10.3389\/fmed.2021.681473","type":"journal-article","created":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T10:29:35Z","timestamp":1626949775000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":18,"title":["Acute Hemodynamic Effect of Acetazolamide in Patients With Pulmonary Hypertension Whilst Breathing Normoxic and Hypoxic Gas: A Randomized Cross-Over Trial"],"prefix":"10.3389","volume":"8","author":[{"given":"Mona","family":"Lichtblau","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlotte","family":"Berlier","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phanie","family":"Saxer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arcangelo F.","family":"Carta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Mayer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra","family":"Groth","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrick R.","family":"Bader","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon R.","family":"Schneider","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Furian","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esther I.","family":"Schwarz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erik R.","family":"Swenson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Konrad E.","family":"Bloch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvia","family":"Ulrich","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,7,22]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1801913","DOI":"10.1183\/13993003.01913-2018","article-title":"Haemodynamic definitions and updated clinical classification of pulmonary hypertension","volume":"53","author":"Simonneau","year":"2018","journal-title":"Eur Respir J."},{"key":"B2","doi-asserted-by":"publisher","first-page":"45","DOI":"10.1159\/000342351","article-title":"Wrist actigraphy predicts outcome in patients with pulmonary hypertension","volume":"86","author":"Ulrich","year":"2013","journal-title":"Respiration."},{"key":"B3","doi-asserted-by":"publisher","first-page":"808","DOI":"10.1183\/09031936.06.00130405","article-title":"Measurement of quality of life in pulmonary hypertension and its significance","volume":"28","author":"Cenedese","year":"2006","journal-title":"Eur Respir J."},{"key":"B4","doi-asserted-by":"publisher","first-page":"110","DOI":"10.1186\/1477-7525-10-110","article-title":"The German adaptation of the Cambridge pulmonary hypertension outcome review (CAMPHOR)","volume":"10","author":"Cima","year":"2012","journal-title":"Health Qual Life Outcomes."},{"key":"B5","doi-asserted-by":"publisher","first-page":"477","DOI":"10.1159\/000341182","article-title":"Daytime measurements underestimate nocturnal oxygen desaturations in pulmonary arterial and chronic thromboembolic pulmonary hypertension","volume":"84","author":"Hildenbrand","year":"2012","journal-title":"Respiration."},{"key":"B6","doi-asserted-by":"publisher","first-page":"1375","DOI":"10.1378\/chest.07-3035","article-title":"Sleep-related breathing disorders in patients with pulmonary hypertension","volume":"133","author":"Ulrich","year":"2008","journal-title":"Chest."},{"key":"B7","doi-asserted-by":"publisher","first-page":"658","DOI":"10.1183\/09031936.02.00225102","article-title":"Nocturnal periodic breathing in primary pulmonary hypertension","volume":"19","author":"Schulz","year":"2002","journal-title":"Eur Respir J."},{"key":"B8","doi-asserted-by":"publisher","first-page":"343","DOI":"10.7326\/0003-4819-115-5-343","article-title":"Survival in patients with primary pulmonary hypertension. 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