Intraoperative hypotension, new onset atrial fibrillation, and adverse outcome after carotid endarterectomy.

BACKGROUND

Information regarding predisposing factors, frequency, and prognostic implications of new onset atrial fibrillation (NOAF) after carotid endarterectomy (CEA) is scarce. We assessed the frequency, risk factors, and the prognostic impact of NOAF after CEA.

METHODS

We assessed every patient undergoing CEA (n = 186) at our academic hospital between 2006 and 2009. Patients underwent continuous electrocardiographic monitoring during surgery and during the rest of hospital stay. We performed univariate and multivariate analyses for identifying variables associated with NOAF and for individualizing variables related to four perioperative adverse outcome measures: a) ischemic stroke; b) ischemic stroke and myocardial infarction, c) ischemic stroke and death, and d) ischemic stroke, myocardial infarction, and death.

RESULTS

The study cohort comprised 186 patients. Overall, NOAF was detected in 7 cases (3.8%). The only variable associated with NOAF was intraoperative hypotension (OR 9.6, 95% CI 1.9-47.4, P = .006). There were no perioperative deaths. NOAF was associated with perioperative ischemic stroke and with the combined outcome of ischemic stroke and myocardial infarction.

CONCLUSIONS

We found a low frequency of NOAF after CEA. Intraoperative hypotension was associated to a higher risk of NOAF. In turn, NOAF was related to adverse postoperative outcome. Further research is needed to clarify the pathophysiological relation between intraoperative hypotension, NOAF, and adverse CEA outcome.