The influence of aneurysm size on perioperative cardiac outcome in elective open infrarenal aortic aneurysm repair

Abstract

Abdominal aortic aneurysm (AAA) size and growth has been found to be associated with local generation of inflammation markers such as interleukin-6. Inflammation also seems to be important in perioperative adverse cardiac events. We hypothesized that patients with a large AAA are at increased risk for cardiac events. Consecutive patients who underwent a computed tomography angiography scan before open elective infrarenal AAA repair between March 2000 and December 2005 at three hospitals were analyzed. All patients were screened for the clinical risk factors of age, gender, angina pectoris, myocardial infarction, heart failure, diabetes, stroke, renal failure, and chronic obstructive pulmonary disease, as well as for cardioprotective medication. Postoperative data on troponin release, creatine kinase/creatine kinase isoenzyme MB, and electrocardiogram were routinely collected on days 1, 3, 7, and 30. The main outcome measure was the combined end point of 30-day cardiovascular death and nonfatal myocardial infarction. Multivariate Cox regression analysis was used to evaluate the influence of AAA size on postoperative cardiac outcome. The study included 500 patients. Their mean age was 69.8 +/- 9.5 years, and 431 (86%) were men. Thirty-one patients (6.2%) had perioperative cardiovascular complications, consisting of 15 (3.0%) cardiovascular deaths and 16 (3.2%) nonfatal myocardial infarctions. After correction for other risk factors, including age, Revised Cardiac Risk Index, medication use, duration of surgery, and intraoperative blood loss, AAA size was independently associated with perioperative nonfatal myocardial infarction and cardiovascular death (3.2% increase in risk for each millimeter added, 95% confidence interval 1.1% to 6.2%, P = .007). A larger AAA size is independently associated with an increased incidence of perioperative cardiovascular complications after elective infrarenal AAA repair.