Retaining the Aortic Fat Pad During Cardiac Surgery Decreases Postoperative Atrial Fibrillation

(#2000-4276 ... April 20, 2000)

Zev Davis, MD,¹ H. Kurt Jacobs, PhD,² Juan Bonilla, MD,¹ Richard R. Anderson, MD,¹ Celia Thomas, RN, MS,¹ William Forst, CST/CFA¹

¹Cardiac Surgery Associates, The Edward Cardiovascular Institute, Edward Hospital, Naperville
²The Institute for Minimally Invasive Surgery, Central DuPage Hospital, Winfield, Illinois.

ABSTRACT

Background: Atrial arrhythmias are a common and serious complication of cardiac surgical procedures. Reports describing pericardiac neurogenic tissue led us to hypothesize that removal of the aortic fat pad could cause an autonomic imbalance and contribute to atrial arrhythmias following cardiac surgery.

Methods: Patients (n=131) underwent either conventional cardiopulmonary bypass surgery (CPB) or off-pump coronary artery bypass (OPCAB) surgery. The aortic fat pad was either left intact or removed. The incidence of de novo atrial arrhythmias during the patient's hospital stay was tabulated. Patients with peri-operative myocardial infarction or pre-existing atrial or supraventricular arrhythmias were excluded.

Results: Demographics, preoperative medications, ASA and NYHA classifications, and complication rates (other than for atrial arrhythmias) did not differ among the groups. The STS-predicted mortality was higher in the CPB/Fat-Pad-Removed group (2.23 ± 1.89) than in either the OPCAB/Fat-Pad-Intact (1.09 ± 0.80) or OPCAB/Fat-Pad-Removed (1.02 ± 0.62) groups (p < 0.05). Atrial arrhythmias were present in 19 of 131 patients (14.5%). Logistic regression demonstrated a significantly elevated atrial arrhythmia rate when the fat pad was removed (odds ratio = 3.49, 95% bounds = 1.09 to 11.18, p = 0.035). Neither the pump status nor the cross product of pump status by fat pad status were significant in this pilot study.

Conclusions: Retaining the aortic fat pad during coronary artery bypass surgery is correlated with a decreased incidence of postoperative atrial arrhythmias.

AUTHOR/ARTICLE INFORMATION

Presented at the Minimally Invasive Cardiac Surgery Symposium, May 28, 2000, Key West, Florida.

Address correspondence and reprint requests to: H. Kurt Jacobs, PhD, TIMIS, 25 N. Winfield Rd., Winfield, Illinois, 60190, Phone: (630) 933-5281, Fax: (630) 933-2700, Email: jacobs@timis.org

Submitted April 17, 2000; accepted April 20, 2000.