Large Retrospective Analysis Shows Equivalent Mortality Rates for EVAR and OAR

May 19, 2010—In the Journal of Vascular Surgery, Philip P. Goodney, MD, et al published findings from a population-based study examining causes of late death after endovascular abdominal aortic aneurysm (AAA) repair (EVAR) compared to open surgical aneurysm repair (OAR) to address several reports that suggest unexpectedly high rates of late AAA ruptures occur after EVAR (2010;51:1340–1347). The investigators concluded that late deaths from aneurysm rupture after EVAR or OAR appear to be relatively infrequent, similarly distributed across procedure type, and that the results emphasize that the effectiveness of EVAR is comparable to OAR in preventing aneurysm-related death.

In the study, the investigators performed a retrospective cohort study of patients undergoing infrarenal AAA repair using information from the Medicare inpatient hospital discharge records (MedPAR files), physician claim files (Part B files, 20% sample), and Medicare Denominator Files for the years 2001 to 2004. Using the Social Security Death Index, the investigators identified all “late” deaths, defined as deaths occurring > 30 days and after hospital discharge. The National Death Index was used to identify cause-of-death information; in particular, deaths that were likely caused by late rupture. Causes of late death and survival between EVAR and OAR were compared using Wilcoxon log-rank and rank-sum tests.

The investigators reported that between 2001 and 2004, 13,971 patients underwent AAA repair (6,119 for EVAR vs 7,852 for OAR). After a mean follow-up of 1.6 years in the EVAR cohort and 1.9 years in the OAR cohort, mortality rates were similar across repair type (EVAR = 15.4% vs OAR = 15.9%), with an adjusted odds ratio for death after OAR of 0.98 (95% confidence interval, 0.9–1.07). Of the 2,194 documented deaths, 523 occurred before discharge or ≤ 30 days, and 1,671 occurred > 30 days and after hospital discharge. Cause-of-death information was available for the 1,515 (91%) of the 1,671 late deaths from the National Death Index. The 15 most common codes for causes of late death were dominated by cardiac disease (atherosclerotic heart disease, acute myocardial infarction) and pulmonary disease (lung cancer, respiratory failure). Causes of late death with specific mention of aneurysm were identified in 37 patients (2.4% of all deaths), but this event was not more common in EVAR compared with OAR (15 [0.3%] vs 22 [0.3%]; P = .71), the investigators reported.