Revised Cardiac Risk Index (Lee) and Perioperative Cardiac Events as Predictors of Long-Term Mortality in Patients Undergoing Endovascular Abdominal Aortic Aneurysm Repair

Abstract

Conclusion: Long-term mortality is high after endovascular repair of abdominal aortic aneurysm (AAA). In the setting of endovascular AAA repair, the Lee Index may be useful for stratifying short-term and long-term mortality in high-risk patients. Summary: Perioperative myocardial infarction remains a vexing problem. In very high-risk vascular surgical patients, perioperative myocardial ischemic injury may be as high as 18% to 35% (J Vasc Surg 2006;43:533-538). Although a large majority of patients survive a perioperative myocardial ischemic event, they are at risk of increased late mortality (J Vasc Surg 1994;20:598-604). Because it appears long-term survival is not improved by endovascular aneurysm repair (EVAR) vs conventional open AAA repair, it is reasonable to investigate whether patients undergoing EVAR can be stratified according to the Revised Cardiac Risk Index (Lee). This was a retrospective review from a single academic medical center involving 225 patients with AAA treated with EVAR between 1999 and 2006. The goal was to determine if the Lee Index is useful is stratifying patients by risk of both perioperative cardiac morbidity and long-term all-cause mortality. Data were collected from physician quality assurance databases, office records, and medical records. There were no in-hospital cardiac deaths. The major cardiac adverse event (MACE) rate perioperatively was 6.2%. Long-term all-cause mortality was 23%. By univariate analysis, a history of coronary artery disease (likelihood ratio [LR], 8.7; P = .023), history of congestive heart failure (LR, 4; P = .042), and a Revised Cardiac Risk Index (RCRI) ≥3 (LR, 8.6; P = .004) were all predictors of perioperative MACE. Long-term all-cause mortality was associated with a history of coronary artery disease (LR, 10.7; P = .002), perioperative cardiac events (LR, 15.9; P < .0001), echocardiographic evidence of myocardial infarction (LR, 8.5; P = .006), and exercise tolerance of only on block (LR, 8.4; P = .005). Long-term mortality is increased after perioperative cardiac events within the RCRI ≥3 subgroup (LR, 6.1; P = .019). Comment: It would seem logical that a patient who develops a myocardial ischemic event after EVAR should undergo further evaluation for coronary artery disease. Long-term survival appears significantly impaired after EVAR, and more so after even a minor myocardial infarction following EVAR. Whether the minor perioperative myocardial event is a cause of long-term mortality or merely a marker of long-term increased cardiac risk is a question that deserves further investigation.