IntroductionComplete denervation of transplanted heart exerts protective effect against
postoperative atrial fibrillation; various degrees of autonomic denervation
appear also after transection of ascending aorta during surgery for aortic
aneurysm.ObjectiveThis study aimed to evaluate if the level of cardiac denervation obtained by
resection of ascending aorta could exert any effect on postoperative atrial
fibrillation incidence.MethodsWe retrospectively analysed the clinical records of 67 patients submitted to
graft replacement of ascending aorta (group A) and 132 with aortic valve
replacement (group B); all episodes of postoperative atrial fibrillation
occurred during the 1-month follow-up have been reported. Heart Rate
Variability parameters were obtained from a 24-h Holter recording; clinical,
echocardiographic and treatment data were also evaluated.ResultsOverall, 45% of patients (group A 43%, group B 46%) presented at least one
episode of postoperative atrial fibrillation. Older age (but not gender,
abnormal glucose tolerance, ejection fraction, left atrial diameter) was
correlated with incidence of postoperative atrial fibrillation. Only among a
subgroup of patients with aortic transection and signs of greater autonomic
derangement (heart rate variability parameters below the median and mean
heart rate over the 75th percentile), possibly indicating more
profound autonomic denervation, a lower incidence of postoperative atrial
fibrillation was observed (22% vs. 54%).ConclusionTransection of ascending aorta for repair of an aortic aneurysm did not
confer any significant protective effect from postoperative atrial
fibrillation in comparison to patients with intact ascending aorta. It could
be speculated that a limited and heterogeneous cardiac denervation was
produced by the intervention, creating an eletrophysiological substrate for
the high incidence of postoperative atrial fibrillation observed.