Stress testing before abdominal aortic aneurysm repair does not lead to a reduction in perioperative cardiac events

Abstract

Objective: Stress testing is often used before abdominal aortic aneurysm (AAA) repair. Whether stress testing leads to a reduction in cardiac events after AAA repair has remained unclear. Our objective was to study the national stress test usage rates and compare the perioperative outcomes between centers with high and low usage of stress testing.

Methods: We used the Vascular Quality Initiative to study patients who had undergone elective endovascular AAA repair (EVAR) or open AAA repair (OAR). We measured the usage rates of stress testing across centers and compared the Vascular Study Group of New England cardiac risk index (VSG-CRI) among patients who had and had not undergone preoperative stress testing. We determined the rate of major adverse cardiac events (MACE), a composite of perioperative myocardial infarction, stroke, heart failure exacerbation, and death across the centers. We compared the MACE and 1-year mortality between the centers in the highest quintile of stress test usage and the lowest quintile.

Results: We studied 43,396 EVAR patients and 8935 OAR patients across 324 centers. The median proportion of stress test usage across centers before EVAR was 35.9% and varied from 10.2% (5th percentile) to 73.7% (95th percentile), with similar variability for OAR (median, 57.9%; 5th percentile, 13.0%; 95th percentile, 86.0%). The mean VSG-CRI for the EVAR group with preoperative stress testing was 5.6 ± 2.1 compared with 5.4 ± 2.1 (P < .001) for the EVAR group without preoperative stress testing. The findings were similar for OAR, with a VSG-CRI of 5.1 ± 2.0 vs 4.8 ± 2.1 (P < .001) for those with and without preoperative stress testing, respectively. The rate of MACE was 1.8% after EVAR and 11.6% after OAR. The 1-year mortality was 4.6% for EVAR and 6.6% for OAR. The centers in the highest quintile of stress testing had a higher adjusted likelihood of MACE after both EVAR (odds ratio [OR], 1.78; 95% confidence interval [CI], 1.37-2.30) and OAR (OR, 1.99; 95% CI, 1.53-2.59) but similar 1-year mortality (EVAR: OR, 1.18; 95% CI, 1.02-1.37; OAR: OR, 0.87; 95% CI, 0.65-1.17) compared with the centers in the lowest quintile. The VSG-CRI was not different between the high stress test centers (EVAR, 5.5 ± 2.1; OAR: 5.0 ± 2.0), and low stress test centers (EVAR, 5.5 ± 2.1; P = .403; OAR, 4.9 ± 2.0; P = .563).

Conclusions: Stress test usage before AAA repair varied widely across Vascular Quality Initiative centers despite similar patient risk profiles. No reduction was observed in MACE or 1-year mortality among centers with high stress test usage. The value of routine stress testing before AAA repair should be reconsidered, and stress testing should be used more selectively, given these findings and the associated costs of widespread testing.

Keywords: AAA repair; Abdominal aortic aneurysm repair; Adverse cardiac events; EVAR; Postoperative complications; Preoperative risk assessment; Preoperative risk stratification; Risk factors; Stress testing; Vascular Quality Initiative.