Long-Term Mortality Benefits With Coronary Artery Bypass Grafting for Ischemic Cardiomyopathy
Clinical question: Does coronary artery bypass grafting added to medical therapy decrease mortality in patients with coronary artery disease and systolic heart failure?
Bottom line: Coronary artery bypass grafting (CABG) plus medical therapy decreases mortality as compared with medical therapy alone in patients with ischemic cardiomyopathy. You would need to treat 14 patients with CABG to prevent one death. (LOE = 1b)
Reference: Velazquez EJ, Lee KL, Jones RH, et al, for the STICHES Investigators. Coronary-artery bypass surgery in patients with ischemic cardiomyopathy. N Engl J Med 2016;374(16):1511-1520.
Study design: Randomized controlled trial (nonblinded)
Funding source: Government
Allocation: Concealed
Setting: Inpatient (any location) with outpatient follow-up
Synopsis: Using concealed allocation, these investigators randomized patients with heart failure with ejection fraction of 35% or less and coronary artery disease amenable to CABG to receive either guideline-directed medical therapy plus CABG (n = 610) or guideline-directed medical therapy alone (n = 602). The 2 groups were similar at baseline and the majority was categorized as New York Heart Failure Association class II. Overall, 91% of the CABG group underwent the procedure within the first year following randomization. Notably, 20% of the medical therapy group also underwent CABG during the long-term follow-up period (11% crossed over to CABG within the first year). The medial duration for follow-up was 9.8 years and analysis was by intention to treat. CABG plus medical therapy resulted in fewer deaths over 10 years as compared with medical therapy alone (59% vs 66%; hazard ratio [HR] = 0.84; 95% CI 0.73 – 0.97; P = .02). The CABG group also had fewer deaths specifically from cardiovascular causes (40% vs 49%; P = .006). A per-protocol analysis showed an even greater benefit with CABG (HR = 0.77; 0.67 – 0.90; P = .001) suggesting that the crossovers in this trial may have diluted the observed effect of CABG.
Dr. Kulkarni is an assistant professor of hospital medicine at Northwestern University in Chicago.
