Quality-of-life outcomes with coronary artery bypass graft surgery in ischemic left ventricular dysfunction: a randomized trial

Abstract

Background: The STICH (Surgical Treatment for Ischemic Heart Failure) trial compared a strategy of routine coronary artery bypass grafting (CABG) with guideline-based medical therapy for patients with ischemic left ventricular dysfunction.

Objective: To describe treatment-related quality-of-life (QOL) outcomes, a major prespecified secondary end point in the STICH trial.

Design: Randomized trial. (ClinicalTrials.gov: NCT00023595).

Setting: 99 clinical sites in 22 countries.

Patients: 1212 patients with a left ventricular ejection fraction of 0.35 or less and coronary artery disease.

Intervention: Random assignment to medical therapy alone (602 patients) or medical therapy plus CABG (610 patients).

Measurements: A battery of QOL instruments at baseline (98.9% complete) and 4, 12, 24, and 36 months after randomization (collection rates were 80% to 89% of those eligible). The principal prespecified QOL measure was the Kansas City Cardiomyopathy Questionnaire, which assesses the effect of heart failure on patients' symptoms, physical function, social limitations, and QOL.

Results: The Kansas City Cardiomyopathy Questionnaire overall summary score was consistently higher (more favorable) in the CABG group than in the medical therapy group by 4.4 points (95% CI, 1.8 to 7.0 points) at 4 months, 5.8 points (CI, 3.1 to 8.6 points) at 12 months, 4.1 points (CI, 1.2 to 7.1 points) at 24 months, and 3.2 points (CI, 0.2 to 6.3 points) at 36 months. Sensitivity analyses to account for the effect of mortality on follow-up QOL measurement were consistent with the primary findings.

Limitation: Therapy was not masked.

Conclusion: In this cohort of symptomatic high-risk patients with ischemic left ventricular dysfunction and multivessel coronary artery disease, CABG plus medical therapy produced clinically important improvements in quality of life compared with medical therapy alone over 36 months.

Primary funding source: National Heart, Lung, and Blood Institute.

Figure 1

KCCQ overall summary scale. Higher scores indicate more favorable quality of life, fewer symptoms, and better functioning. Data are shown by intention to treat. Values below the x-axis are the numbers of patients with questionnaire data, patients who died, patients with missing questionnaire data, and patients with provided questionnaire data who had received CABG surgery at each follow-up assessment. CABG = coronary artery bypass grafting; KCCQ = Kansas City Cardiomyopathy Questionnaire.

Figure 2

SAQ angina frequency scale. Higher scores on the frequency scale reflect lower incidence of angina symptoms. Values below the x-axis are the numbers of patients with questionnaire data, patients who died, and patients with missing questionnaire data at each follow-up assessment. CABG = coronary artery bypass grafting; SAQ = Seattle Angina Questionnaire.