{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T09:54:59Z","timestamp":1792144499126,"version":"4.4.0"},"reference-count":57,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T00:00:00Z","timestamp":1765411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Postoperative thrombocytopenia is a frequent finding after cardiac surgery, affecting approximately 10\u201340% of patients. The early decline in platelet count, typically observed within the first 48\u201372 h, is usually explained by hemodilution, perioperative platelet consumption, and the inflammatory or mechanical impact of cardiopulmonary bypass (CPB). However, a secondary decrease occurring beyond postoperative day 5 should raise suspicion for more serious causes, the most important being heparin-induced thrombocytopenia (HIT), a rare but potentially life-threatening complication. Objectives: This review aims to outline the characteristic patterns of postoperative thrombocytopenia in cardiac surgery, provide a practical framework for differential diagnosis, and summarize up-to-date evidence on the diagnosis and management of HIT. Methods: A narrative review was conducted through searches in PubMed, Scopus, and Embase up to September 2025. Conclusions: Recognizing platelet count trends early and applying a stepwise diagnostic approach can help distinguish benign postoperative thrombocytopenia from HIT and other critical causes. The combination of clinical assessment using the 4Ts score and appropriate confirmatory testing remains central to accurate diagnosis. Tailoring anticoagulant therapy to individual patient requirements\u2014including surgical procedure, renal and hepatic function, and bleeding risk\u2014is essential for reducing thrombotic events and improving postoperative outcomes.<\/jats:p>","DOI":"10.3390\/jcm14248765","type":"journal-article","created":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T12:57:41Z","timestamp":1765457861000},"page":"8765","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Postoperative Thrombocytopenia in Cardiac Surgery: Patterns, Differential Diagnosis and Management of Heparin-Induced Thrombocytopenia (HIT)"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0775-035X","authenticated-orcid":false,"given":"Fotini","family":"Ampatzidou","sequence":"first","affiliation":[{"name":"ICU Department, George Papanikolaou General Hospital of Thessaloniki, 570 10 Exochi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleni","family":"Argyriadou","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Intensive Care, AHEPA University Hospital, 546 36 Thessaloniki, Greece"},{"name":"Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine","family":"Amaniti","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Intensive Care, AHEPA University Hospital, 546 36 Thessaloniki, Greece"},{"name":"Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4810-3829","authenticated-orcid":false,"given":"Despoina","family":"Sarridou","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Intensive Care, AHEPA University Hospital, 546 36 Thessaloniki, Greece"},{"name":"Faculty of Health Sciences, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1182\/blood.V77.1.31.31","article-title":"High risk of severe bleeding in aged patients with chronic idiopathic thrombocytopenic purpura","volume":"77","author":"Cortelazzo","year":"1991","journal-title":"Blood"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1186\/s13613-025-01447-x","article-title":"Thrombocytopenia in the intensive care unit: Diagnosis and management","volume":"15","author":"Russell","year":"2025","journal-title":"Ann. 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