Anders Hebert1, Annette S Jensen2, Ulla R Mikkelsen3, Lars Idorn2, Keld E Sørensen4, Ulf Thilen5, Katarina Hanseus6, Lars Søndergaard2. 1. Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Denmark. Electronic address: andershebert@gmail.com. 2. Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Denmark. 3. Institute of Sports Medicine, Department of Orthopedic Surgery, Bispebjerg Hospital and Center for Healthy Ageing, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark. 4. Department of Cardiology, Aarhus University Hospital, Skejby, Aarhus, Denmark. 5. Department of Cardiology, University Hospital of Lund, Sweden. 6. Department of Pediatric Cardiology, University Hospital of Lund, Sweden.
Abstract
BACKGROUND: Exercise intolerance is frequent among Fontan patients and an important determinant for quality of life. This study investigated the hemodynamic causes of impaired exercise capacity in Fontan patients with particular focus on the influence of stroke volume index (SVI) and heart rate (HR). METHODS AND RESULTS: In 38 Fontan patients, peak oxygen consumption (VO2), SVI and HR were recorded during incremental load exercise test and compared with 19 age and gender matched controls. SVI (ml/m(2)) was lower in patients than controls during warm-up (28[26-31] vs. 35[30-39], p=0.0093), at submaximal (40[37-43] vs. 55[51-59], p<0.0001) and at maximal exercise (38[35-40] vs. 54[51-58], p<0.0001). Similarly, HR (% of expected maximum) was lower in patients at warm-up (45[43-48]% vs. 64[57-64]%, p<0.0001), submaximal (71[68-75]% vs 85[82-88]%, p<0.0001) and maximal exercise (84[80-88]% vs. 97[95-99]%, p<0.0001). Furthermore, SVI dropped 14% (from 44[41-48] to 38[35-40] ml/m(2)) in Fontan patients from the peak plateau to maximal exercise vs. 5% (from 57[53-61] to 54[51-58] ml/m(2)) in controls, p<0.0001. The low SVI and HR explained 67% and 20% of the difference in peak VO2 between Fontan patients and controls respectively. CONCLUSION: SVI decreased significantly in Fontan patients near the end of maximal effort exercise. The low SVI at maximal exercise was the most important hemodynamic factor limiting exercise capacity in Fontan patients, whereas chronotropic impairment had a smaller impact. The low SVI and HR at maximal exercise accounted for the difference in peak VO₂ between Fontan patients and controls in this study. CLINICAL TRIAL REGISTRATION: http://www.cvk.sum.dk/CVK/Home/English.aspx (protocol nr: H-3-2010-045).
BACKGROUND: Exercise intolerance is frequent among Fontan patients and an important determinant for quality of life. This study investigated the hemodynamic causes of impaired exercise capacity in Fontan patients with particular focus on the influence of stroke volume index (SVI) and heart rate (HR). METHODS AND RESULTS: In 38 Fontan patients, peak oxygen consumption (VO2), SVI and HR were recorded during incremental load exercise test and compared with 19 age and gender matched controls. SVI (ml/m(2)) was lower in patients than controls during warm-up (28[26-31] vs. 35[30-39], p=0.0093), at submaximal (40[37-43] vs. 55[51-59], p<0.0001) and at maximal exercise (38[35-40] vs. 54[51-58], p<0.0001). Similarly, HR (% of expected maximum) was lower in patients at warm-up (45[43-48]% vs. 64[57-64]%, p<0.0001), submaximal (71[68-75]% vs 85[82-88]%, p<0.0001) and maximal exercise (84[80-88]% vs. 97[95-99]%, p<0.0001). Furthermore, SVI dropped 14% (from 44[41-48] to 38[35-40] ml/m(2)) in Fontan patients from the peak plateau to maximal exercise vs. 5% (from 57[53-61] to 54[51-58] ml/m(2)) in controls, p<0.0001. The low SVI and HR explained 67% and 20% of the difference in peak VO2 between Fontan patients and controls respectively. CONCLUSION: SVI decreased significantly in Fontan patients near the end of maximal effort exercise. The low SVI at maximal exercise was the most important hemodynamic factor limiting exercise capacity in Fontan patients, whereas chronotropic impairment had a smaller impact. The low SVI and HR at maximal exercise accounted for the difference in peak VO₂ between Fontan patients and controls in this study. CLINICAL TRIAL REGISTRATION: http://www.cvk.sum.dk/CVK/Home/English.aspx (protocol nr: H-3-2010-045).
Authors: Andrew Constantine; Konstantinos Dimopoulos; Petra Jenkins; Robert M R Tulloh; Robin Condliffe; Katrijn Jansen; Natali A Y Chung; James Oliver; Helen Parry; Samantha Fitzsimmons; Niki Walker; Stephen John Wort; Vasilios Papaioannou; Kate von Klemperer; Paul Clift Journal: J Am Heart Assoc Date: 2021-12-20 Impact factor: 6.106
Authors: Hermann Körperich; Katja Müller; Peter Barth; Jürgen Gieseke; Nikolaus Haas; Ingram Schulze-Neick; Wolfgang Burchert; Deniz Kececioglu; Kai T Laser Journal: J Thorac Imaging Date: 2017-05 Impact factor: 3.000