Exercise training improves insulin-stimulated myocardial glucose uptake in patients with dilated cardiomyopathy

J Nucl Cardiol. Sep-Oct 2003;10(5):447-55. doi: 10.1016/s1071-3581(03)00528-2.

Abstract

Background: The effects of exercise training on myocardial substrate utilization have not previously been studied in patients with idiopathic dilated cardiomyopathy and mild heart failure.

Methods and results: Myocardial glucose uptake was studied in 15 clinically stable patients with dilated cardiomyopathy (New York Heart Association class I-II, ejection fraction 34% +/- 8%) with the use of 2-[fluorine 18]fluoro-2-deoxy-d-glucose ([F-18]FDG) and positron emission tomography under euglycemic hyperinsulinemia. Eight of these patients participated in a 5-month endurance and strength training program, whereas seven patients served as nontrained subjects. Left ventricular function was assessed by 2-dimensional echocardiography before and after the intervention. After the training period, insulin-stimulated myocardial fractional [F-18]FDG uptake and glucose uptake rates were significantly increased in the anterior, lateral, and septal walls (P <.01) in the trained subjects but remained unchanged in the nontrained subjects. In the trained patients, whole-body insulin-stimulated glucose uptake was enhanced and serum free fatty acid levels were suppressed during hyperinsulinemia compared with the baseline study (P <.05). No changes were observed in the nontrained group.

Conclusions: These results indicate that exercise training in patients with dilated cardiomyopathy improves insulin-stimulated myocardial glucose uptake. This improvement in glucose uptake may be indicative of a switch in myocardial preference to a more energy-efficient substrate.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Blood Glucose / analysis
  • Cardiomyopathy, Dilated / complications
  • Cardiomyopathy, Dilated / diagnosis
  • Cardiomyopathy, Dilated / metabolism*
  • Cardiomyopathy, Dilated / therapy*
  • Echocardiography
  • Exercise Test
  • Exercise Therapy / methods*
  • Female
  • Fluorodeoxyglucose F18 / pharmacokinetics
  • Glucose Clamp Technique / methods*
  • Humans
  • Insulin
  • Male
  • Middle Aged
  • Myocardium / metabolism*
  • Radiopharmaceuticals / pharmacokinetics
  • Recovery of Function
  • Treatment Outcome
  • Ventricular Dysfunction, Left / diagnosis
  • Ventricular Dysfunction, Left / etiology
  • Ventricular Dysfunction, Left / metabolism*
  • Ventricular Dysfunction, Left / therapy*

Substances

  • Blood Glucose
  • Insulin
  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18