Introduction:
Diabetes mellitus (DM), coronary artery disease (CAD) and heart failure commonly coexist. Hypothesis 1 of the Surgical Treatment for Ischemic Heart Failure (STICH) trial enrolled 1212 patients with a left ventricular ejection fraction (LVEF) of 35% or less and CAD amenable to CABG. Patients were randomised to CABG and optimal medical therapy (OMT) or OMT alone.
Hypothesis:
We assessed the hypothesis that patients with DM enrolled in the STICH trial would have greater benefit of CABG than patients without DM.
Methods:
We compared the characteristics and clinical outcomes of patients with and without DM randomized to CABG and OMT or OMT alone. Cox-proportional hazards analyses were used to assess treatment effect.
Results:
Diabetes was present in 40.3%. At baseline, patients with DM had more triple vessel CAD (66% v 57%, p<0.001), higher LVEF [median 29% (IQR:22,35) vs 27% (IQR:22,33), p=0.015] and smaller left ventricular end diastolic volume index [median 105 ml/m2 (IQR:85, 128) vs 117 ml/m2 (IQR:93, 146) (p<0.001)]. Among patients with DM, there was a higher proportion of females, higher BMI on average, worse renal function, and more hypertension. Patients with DM undergoing CABG spent longer on cardio-pulmonary bypass [median 97 (IQR:71,126) vs 87 (IQR:65, 115) minutes, p=0.029], and were more likely to develop perioperative AF (23% vs 11%, p<0.001) and worsening renal function (9% vs 4%, p=0.021). Patients with DM on OMT had similar outcomes as those on OMT without diabetes (Table 1). A statistically significant or near statistically significant improvement in clinical outcomes with CABG compared to OMT was documented in patients without DM, but not in patients with DM. However, there was no significant interaction between DM and treatment group on formal statistical testing.
Conclusions:
Patients with and without DM enrolled in the STICH trial had similar outcomes at 5 years, and CABG did not exert greater benefit in patients with DM.
The STICH Trial (Surgical Treatment for Ischemic Heart Failure)
