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Atrial Fibrillation Is Associated with Decreased Cardiac Sympathetic Response to Isometric Exercise in CHF in Comparison to Sinus Rhythm
Author(s) -
GOULD PAUL A.,
ESLER MURRAY D.,
KAYE DAVID M.
Publication year - 2008
Publication title -
pacing and clinical electrophysiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.686
H-Index - 101
eISSN - 1540-8159
pISSN - 0147-8389
DOI - 10.1111/j.1540-8159.2008.01152.x
Subject(s) - medicine , cardiology , heart failure , atrial fibrillation , sinus rhythm , isometric exercise , haemodynamic response , hemodynamics , ejection fraction , baroreceptor , heart rate , blood pressure
Background: The presence of atrial fibrillation (AF) in congestive heart failure (CHF) is accompanied by increased mortality, although the exact mechanism is unclear. In previous studies, we have demonstrated cardiac baroreceptor abnormalities in association with AF and CHF. In this study, we sought to examine the effect of cardiac rhythm on the cardiac sympathetic response to exercise in CHF.Methods: In 13 CHF patients (six AF, seven SR, left ventricular ejection fraction 31 ± 2%, age 61 ± 1 years), we measured the hemodynamic and cardiac sympathetic response isometric handgrip (IHG) exercise.Results: At baseline the groups were well matched. Baseline hemodynamics and cardiac sympathetic activity did not significantly differ between the cohorts. In response to IHG exercise, both groups demonstrated significant hemodynamic responses. In conjunction, the sinus rhythm (SR) group demonstrated a significant increase in cardiac sympathetic response to exercise (P = 0.04) while in contrast the AF group did not (P = 0.6).Conclusion: In this study, we demonstrate for the first time that the combination of AF and CHF is accompanied by a marked attenuation of the cardiac sympathetic response to acute hemodynamic stress. This implies AF is associated with a further impairment of baroreceptor response in CHF compared to SR. These findings present possible insights to the associated increased mortality and pathogenesis of AF with CHF.