Iron deficiency in patients with a Fontan circulation and its impact on exercise capacity.
Gaston van Hassel, Sean C S Rivrud, Frank J Timmerman, Peter van der Meer, Elke S Hoendermis, Eryn T Liem, Rolf M F Berger, Joost P van Melle
Author Information
Gaston van Hassel: Center for Congential Heart Diseases, Department of Paediatric Cardiology, Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands g.van.hassel@umcg.nl. ORCID
Sean C S Rivrud: Department of Cardiology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
Frank J Timmerman: Department of Cardiology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
Peter van der Meer: Department of Cardiology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
Elke S Hoendermis: Department of Cardiology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
Eryn T Liem: Center for Congential Heart Diseases, Department of Paediatric Cardiology, Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
Rolf M F Berger: Center for Congential Heart Diseases, Department of Paediatric Cardiology, Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands.
Joost P van Melle: Department of Cardiology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands. ORCID
BACKGROUND: 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. METHODS AND RESULTS: Blood count and haematological parameters were determined in plasma of 61 Fontan patients (51% female, mean age 29��9 years). ID was defined as transferrin saturation (TSAT) ���19.8%. 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��18.4 g/L). Mean ferritin levels were 98��80 ��g/L and mean TSAT levels were 22%��12%. Cardiopulmonary exercise testing was performed in 46 patients (75%). Patients with ID had a lower peak oxygen uptake (V��Opeak) (1397��477 vs 1692��530 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) ���1.1 by 5-fold (p=0.035). CONCLUSION: ID is highly prevalent among patients with a Fontan circulation. V��Opeak is lower in patients with ID. Fontan patients with ID are less likely to achieve an RER���1.1 during cardiopulmonary exercise testing.
