['Sac shrinkage is a surrogate marker of success after endovascular aneurysm repair (EVAR). We set out to determine if any common cardioprotective medications had a beneficial effect on sac shrinkage.', 'This retrospective observational study took place at Leeds Vascular Institute, a tertiary vascular unit in the Northern United Kingdom. The cohort comprised 149 patients undergoing EVAR between January 1, 2005, and December 31, 2008. Medication use was recorded at intervention (verified at study completion in 33 patients), and patients were monitored for 2 years. The main outcome measures were the effect of medication on sac shrinkage as determined by percentage change in maximal idealized cross-sectional area of the aneurysm at 1 month, 6 months, 1 year, and 2 years by linear regression model, in addition to 2-year endoleak and death rates determined by a binary logistic regression model.', 'After exclusions, 112 patients, who were a median age of 78 years (interquartile range, 78-83 years), remained for analysis. The median Glasgow Aneurysm Score was 85 (interquartile range, 79-92). At 2 years, mortality was 13.4%, endoleak developed in 37.5%, and significant endoleak developed in 14.3%. Patients taking a calcium channel blocker had enhanced sac shrinkage, compared with those not taking a calcium channel blocker, by 6.6% at 6 months (-3.0% to 16.3%, P = .09), 12.3% at 1 year (2.9% to 21.7%, P = .008), and 13.1% at 2 years (0.005% to 26.2%, P = .007) independent of other medication use, graft type, endoleak development, or death.'] Do calcium channel blockers enhance sac shrinkage after endovascular aneurysm repair?