Long-Term Outcomes of Coronary Artery Bypass Grafting in Veterans with Ischemic Cardiomyopathy

The Surgical Treatment for Ischemic Heart Failure (STICH) trial showed that surgical revascularization in ischemic cardiomyopathy (ICM) patients improves long-term mortality compared with medical treatment alone. This study examines how veterans with ICM undergoing revascularization fare against patients without ICM; it also examines the outcomes in the veteran population.

This is a retrospective review of a single-center database. From 2000 to 2018, 1,461 patients underwent isolated coronary artery bypass grafting (CABG). Two-hundred-one patients with an ejection fraction less than 35% were classified as the ICM cohort. The primary outcome was mortality. Secondary outcomes included postoperative complications. Subgroup analysis was performed within the ICM cohort comparing off-pump CABG (OPCAB) versus on-pump CABG (ONCAB).

ICM patients had a higher incidence of myocardial infarction (MI), diabetes, chronic kidney disease (CKD), and preoperative intra-aortic balloon pump (IABP) use. The non-ICM cohort was more functionally independent. OPCAB was performed in 80.1% of ICM and 66.3% of non-ICM cohorts. There was no statistical difference between ICM and non-ICM cohorts in 30-day mortality (OR 1.94[0.79 - 4.75], P = .15). The ICM cohort had an increased 5-year mortality (OR 1.75[1.14 - 2.69], P = .01) and 10-year mortality (OR 1.71[1.09 - 2.67], P = .02). The ICM cohort showed improved, although not statistically significant, short-term mortality with OPCAB compared with ONCAB (3.1% versus 12.5%, OR 0.31[0.05 - 1.82], P = .20).

Veterans with ICM undergoing CABG demonstrated similar short-term survival compared with non-ICM veterans. The long-term survival in the ICM cohort still is inferior to patients without ICM. There is a trend toward improved short-term survival in patients with ICM undergoing OPCAB.