Article

OBJECTIVE: To investigate vagal parasympathetic functions by electromyographic
R-R interval variation analyses in heart transplant recipients. DESIGN:
Cross-sectional and longitudinal study. SETTING: Department of physical medicine
and rehabilitation, university hospital. PARTICIPANTS: Early (n=8; <3 mo) and
late (n=17; >1 y) heart transplant recipients and healthy volunteers (n=20) were
included. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The R-R interval
variations at rest and in response to deep breathing, Valsalva, and tilt/standup
maneuvers were analyzed in all patient and control groups. Further, 8 early heart
transplant recipients were followed up at the sixth and twelfth months after
transplantation. RESULTS: Compared with controls, both early and late transplant
recipients had significantly lower R-R interval variation ratios (P<.05). There
were no statistically significant differences between the early and late groups
(P>.05). R-R interval variation ratios showed no significant changes from
baseline (P>.025) in the early heart transplant recipients. CONCLUSIONS: The
findings of the study suggest that parasympathetic activities are suppressed in
the early stage after heart transplantation and do not significantly recover with
time. The electromyographic analysis of R-R interval variation is a simple test
that may offer an attractive alternative for routine evaluation of autonomic
dysfunction in heart transplant recipients.

Langue : ANGLAIS