Abstract 17348: Glucagon-like Peptide-1 Improves the Myocardial Response to Demand Ischemia During Hyperglycemia in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease
Background: The incretin hormone glucagon-like peptide-1 (GLP-1) appears to enhance myocardial glucose uptake, which may reduce fatty acid oxidation and improve myocardial tolerance to ischemia. Hyperglycemia, in association with hyperinsulinemia, also stimulates this metabolic change, but may also have deleterious effects on left ventricular (LV) function. We hypothesized that GLP-1 would improve myocardial function in the setting of hyperglycemia during dobutamine stress echocardiography (DSE) in patients with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD).
METHODS: 10 patients (age 66 ± 5 years, all male) with T2DM, obstructive CAD and normal resting LV systolic function underwent two DSE (in randomized order) during the steady-state phase of a hyperglycemic clamp. During one of the scans, intravenous GLP-1 was infused concomitantly at 1.2pmol/kg/min, and the other scan acted as a control. Tissue Doppler imaging was acquired in 3 apical views at rest, peak stress and 30 minutes recovery to assess for parameters of global [mitral annular peak systolic velocity (MASV)] and regional [peak systolic tissue velocity (Vs), strain (S) and strain rate (SR)] function.
RESULTS: At rest, all parameters of LV function were unchanged between control and GLP-1 scans. Blood glucose levels (261 ± 32 vs 267 ± 32mg/dl, p=0.40) and RPP (p=0.66) attained at peak stress were the same for both DSE studies but myocardial performance was enhanced following GLP-1 (MASV 12.9 ± 3.2 vs 12.5 ± 3.2cm/s, p=0.04; Vs 10.4 ± 3.6 vs 10.0 ± 3.6cm/s, p=0.07; S -18.4 ± 7.4 vs -15.8 ± 5.4%, p<0.001; SR -2.46 ± 0.8 vs -2.2 ± 0.7s-1, p<0.001). At 30 minutes recovery, ischemic LV dysfunction did not occur after GLP-1 (Vs 5.01 ± 1.9 vs 4.69 ± 1.6cm/s, p=0.01; S -16.0 ± 5.6 vs -14.7 ± 5.5%, p=0.03; SR -1.22 ± 0.4 vs -1.03 ± 0.3s-1, p<0.001).
CONCLUSION: In patients with T2DM and CAD, GLP-1 improves myocardial tolerance to demand ischemia during hyperglycemia and mitigates post-ischemic stunning.
- © 2013 by American Heart Association, Inc.