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.
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.
Authors: T R Wallhaus; M Taylor; T R DeGrado; D C Russell; P Stanko; R J Nickles; C K Stone Journal: Circulation Date: 2001-05-22 Impact factor: 29.690
Authors: M J Knuuti; M Mäki; H Yki-Järvinen; L M Voipio-Pulkki; R Härkönen; M Haaparanta; P Nuutila Journal: J Mol Cell Cardiol Date: 1995-07 Impact factor: 5.000
Authors: R Hambrecht; E Fiehn; C Weigl; S Gielen; C Hamann; R Kaiser; J Yu; V Adams; J Niebauer; G Schuler Journal: Circulation Date: 1998-12-15 Impact factor: 29.690
Authors: Pablo F Soto; Pilar Herrero; Kenneth B Schechtman; Alan D Waggoner; Jeffrey M Baumstark; Ali A Ehsani; Robert J Gropler Journal: Am J Physiol Heart Circ Physiol Date: 2008-06-20 Impact factor: 4.733