Study Demonstrates Benefit of Pre-EVAR Statin Therapy

May 19, 2010—The Society for Vascular Surgery (SVS) announced findings showing that preoperative statin therapy has a protective effect on patients undergoing elective repair for abdominal aortic aneurysms (AAAs) and reduces risk and subsequent total hospital costs. Michael M. McNally, MD, et al published the study in the Journal of Vascular Surgery (2010;51:1390–1396).

Their retrospective review compares 401 patients who underwent an elective endovascular AAA repair (EVAR) or open AAA repair (OAR) between 2004 and 2007. Clinical endpoints included postoperative days; length of hospital stay; postoperative complications (myocardial infarction, stroke, renal failure, hemorrhage, pneumonia, and urinary tract and wound infections); 30-day mortality; and total hospital cost associated with the procedures.

“Both groups (173 patients for EVAR and 228 patients for OAR) were evenly matched, with the only significant differences being that the EVAR cohort was older and patients with end-stage renal disease were only offered EVAR repair,” commented lead investigator Michael C. Stoner, MD. “EVAR patients were also more likely to be on a statin or beta blocker before surgery.”

Dr. Stoner stated that despite a higher SVS risk score, the EVAR statin cohort had significantly reduced postoperative days (1.9 ± 0.2 vs 2.3 ± 0.3) and hospital length of stay (2.3 ± 0.3 vs 2.8 ± 0.4) compared to the nonstatin EVAR cohort. Postoperative complications (4.4% vs 14.7%) and mortality (0% vs 5.9%) were significantly decreased in the open statin cohort compared to the nonstatin open cohort and trended to be decreased in the EVAR statin group. Importantly, Dr. Stoner noted, use of statin therapy translated into improved total cost per patient in both treatment groups ($3,205 per case for EVAR and $3,792 per case for OAR).

The investigators also found that there were no 30-day deaths in the statin EVAR group despite equal rates of myocardial infarction between the cohorts, which could be caused by the protective benefit of these agents in the coronary vascular bed and their ability to limit the extent of myocardial ischemic injury. The investigators also acknowledged the potential confounding issues associated with retrospective studies such as this.

“We found that overall statin use in this study was quite low (40.4% for OAR and 51.4% for EVAR),” added Dr. Stoner. “This might suggest a heterogeneous access to care because a relatively small percentage of patients were receiving appropriate medical therapy at time of referral, most likely related to the low socioeconomic status and geographic barrier to care seen in rural academic practices such as ours.”

Dr. Stoner stated that before this study, the team of investigators from East Carolina University tended not to start AAA patients on statins but simply recommended their use, which was communicated back to the referring or primary doctor at the time of consultation. Now, they initiate statin pharmacotherapy for all elective AAA patients at the initial consultation based on Class II American Heart Association guidelines, unless there is a specific contraindication, regardless of lipid profile. The therapy is continued through the operation until the first postoperative visit. They then make a recommendation to continue medical therapy with the patient's primary physician. The investigators are currently following this practice change in a prospective manner and will report on its impact.

Dr. Stoner concluded, “Evidence examining statin therapy in elective AAA repair has been limited but our study showing improved patient outcomes and lower overall health care costs suggests that preoperative statin therapy should be an integral part of the risk optimization for patients undergoing this procedure.”