A prospective study of subclinical myocardial damage in endovascular versus open repair of infrarenal abdominal aortic aneurysms.

Abstract

Endovascular repair of abdominal aortic aneurysms (AAAs) is considered to be less invasive and better tolerated by the cardiovascular system than open repair. Our aim was to assess the true incidence of perioperative myocardial damage associated with endovascular vs open infrarenal AAA repair. Between July 1999 and June 2001, preoperative and postoperative serum troponin T (TnT) levels were measured in all patients presenting for elective AAA repair at Royal Prince Alfred Hospital. The incidence of myocardial damage was recorded on the basis of standard clinical, biochemical, and electrocardiographic changes or a subclinical increase of 50% or more in serum TnT. Patients were excluded if the TnT increase was associated with a significant increase of serum creatinine (> or =50%) with no other evidence of myocardial ischemia. The differences between the two groups were analyzed with the chi 2 test and odds ratios. A total of 35 open and 112 endovascular AAA repairs were included in the study. There was no significant difference in age, sex, preoperative serum creatinine, or preoperative serum TnT between the two treatment groups. Seventeen patients had biochemical evidence of myocardial damage, which was clinically obvious in only one patient. Even though the incidence of previous myocardial infarction was significantly higher in patients undergoing endovascular repair (41%) than open repair (22%; P < .05), the overall incidence of myocardial damage (clinical or subclinical) was significantly higher in the open group compared with the endovascular group (8 [25%] of 32 vs 9 [8%] of 109, respectively; odds ratio, 3.7; 95% confidence interval, 1.28-10.49; P < .02). There is a previously underestimated incidence of subclinical myocardial damage associated with surgery for infrarenal AAA which is lower after endovascular than open repair.