{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,7]],"date-time":"2026-11-07T03:44:10Z","timestamp":1794023050714,"version":"4.8.0"},"reference-count":28,"publisher":"BMJ","issue":"1","license":[{"start":{"date-parts":[[2024,6,5]],"date-time":"2024-06-05T00:00:00Z","timestamp":1717545600000},"content-version":"unspecified","delay-in-days":4,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Open Heart"],"accepted":{"date-parts":[[2024,5,8]]},"published-print":{"date-parts":[[2024,6]]},"abstract":"<jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Iron deficiency (ID) has been reported in patients with congenital heart disease. There is, however, a scarcity of data on its prevalence in patients with a Fontan circulation. The aim of this study is to investigate the prevalence of ID in Fontan patients and to investigate the association between ID and exercise capacity in this population.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods and results<\/jats:title>\n                  <jats:p>Blood count and haematological parameters were determined in plasma of 61 Fontan patients (51% female, mean age 29\u00b19 years). ID was defined as transferrin saturation (TSAT) \u226419.8%. The prevalence of ID was 36% (22\/61 patients). Especially among women, the diagnosis of ID was highly prevalent (52%) despite normal haemoglobin levels (153.7\u00b118.4 g\/L). Mean ferritin levels were 98\u00b180 \u00b5g\/L and mean TSAT levels were 22%\u00b112%. Cardiopulmonary exercise testing was performed in 46 patients (75%). Patients with ID had a lower peak oxygen uptake (V\u0307O<jats:sub>2<\/jats:sub>peak) (1397\u00b1477 vs 1692\u00b1530 mL\/min; p=0.039), although this relationship was confounded by sex. The presence of ID increased the likelihood of not achieving a respiratory exchange ratio (RER) \u22651.1 by 5-fold (p=0.035).<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusion<\/jats:title>\n                  <jats:p>ID is highly prevalent among patients with a Fontan circulation. V\u0307O<jats:sub>2<\/jats:sub>peak is lower in patients with ID. Fontan patients with ID are less likely to achieve an RER\u22651.1 during cardiopulmonary exercise testing.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1136\/openhrt-2024-002693","type":"journal-article","created":{"date-parts":[[2024,6,5]],"date-time":"2024-06-05T21:30:19Z","timestamp":1717623019000},"page":"e002693","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":8,"title":["Iron deficiency in patients with a Fontan circulation and its impact on exercise capacity"],"prefix":"10.1136","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1552-9631","authenticated-orcid":false,"given":"Gaston","family":"van Hassel","sequence":"first","affiliation":[{"name":"Center for Congential Heart Diseases, Department of Paediatric Cardiology, Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, The 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University of Groningen, Groningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eryn T","family":"Liem","sequence":"additional","affiliation":[{"name":"Center for Congential Heart Diseases, Department of Paediatric Cardiology, Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rolf M F","family":"Berger","sequence":"additional","affiliation":[{"name":"Center for Congential Heart Diseases, Department of Paediatric Cardiology, Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4282-4628","authenticated-orcid":false,"given":"Joost P","family":"van Melle","sequence":"additional","affiliation":[{"name":"Department of Cardiology, University Medical Centre Groningen, 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