title: Vagal reactivation after exercise and cardiac autonomic nervous activity in adult Fontan patients without pacemakers.
abstract: OBJECTIVE
  Patients with Fontan circulation have reduced heart rate variability (HRV) in supine position. However, neither cardiac autonomic nervous activity (CANA) in response to orthostatic challenge nor vagal reactivation by means of heart rate (HR) recovery after cessation of exercise have previously been investigated in Fontan patients. The aim of this study was to compare HRV in supine and standing position, as well as HR recovery between Fontan patients and healthy controls.
  
  
  METHODS
  Eight Fontan patients (4 male/4 female) without pacemakers and 12 healthy volunteers (5m/7f) with minimum age of 18years were recruited. HR was measured by Holter-electrocardiogram. HRV was measured in supine position and after orthostatic challenge. The power of the high frequency (HF: 0.15Hz-0.4Hz) and low frequency (LF: 0.04Hz-0.15Hz) bands was analysed by fast-Fourier transformation. HR recovery was determined at 30s and 60s after termination of a maximal exercise test.
  
  
  RESULTS
  In both supine and standing position, total power, HF and LF power were reduced in Fontan patients compared to controls (by approximately a factor of 10) while there was no differences in LF/HF power ratio. Response to orthostatic challenge was blunted in absolute power but normal in relative power. HR recovery was not different between groups.
  
  
  CONCLUSIONS
  Fontan patients have greatly reduced HRV, a blood-pressure dependent marker of CANA, but normal HR recovery, a blood pressure independent marker of vagal reactivation, suggesting that vagal activity may be normal, and only vascular capacitance reduced.
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland. Electronic address: Prisca.eser@insel.ch.
authors.forename: Prisca
authors.initials: P
authors.lastname: Eser
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: David
authors.initials: D
authors.lastname: Herzig
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland; Department of Health Sciences and Technology, ETH Zurich, Switzerland.
authors.forename: Marcel
authors.initials: M
authors.lastname: Vogt
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland; Department of Health Sciences and Technology, ETH Zurich, Switzerland.
authors.forename: Roger
authors.initials: R
authors.lastname: Stämpfli
authors.affiliation: University Clinic of Cardiology, Clinical Research Unit, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Moreno
authors.initials: M
authors.lastname: Trovato
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Daniela Schäfer
authors.initials: DS
authors.lastname: Olstad
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Lukas
authors.initials: L
authors.lastname: Trachsel
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Christina
authors.initials: C
authors.lastname: Deluigi
authors.affiliation: University Clinic of Cardiology, Center for Congenital Heart Disease, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Wustmann
authors.affiliation: Department of Cardiology, University Hospital, Zurich, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Greutmann
authors.affiliation: Department of Cardiology, University Hospital, Basel, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Tobler
authors.affiliation: Department of Cardiology, Kantonsspital, St. Gallen, Switzerland.
authors.forename: Dominik
authors.initials: D
authors.lastname: Stambach
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Schmid
authors.affiliation: University Clinic of Cardiology, Center for Congenital Heart Disease, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Markus
authors.initials: M
authors.lastname: Schwerzmann
authors.affiliation: University Clinic of Cardiology, Preventive Cardiology and Sports Medicine, Inselspital, University Hospital, Bern, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Wilhelm
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology*; D015716:Electrocardiography, Ambulatory / Q000379:methods / Q000639:trends; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000639:trends*; D005260:Female; D018729:Fontan Procedure / Q000639:trends*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D014630:Vagus Nerve / Q000502:physiology*
keywords: Cardiac autonomic nervous system; Fontan patients; Grown-ups with congenital heart disease; Heart rate recovery; Heart rate variability; Orthostatic challenge