BACKGROUND: The treadmill exercise test is the most important examination of the functional ability of patients with intermittent claudication or leg pain during exercise, but it does not provide any metabolic information in the calf muscle. The purpose of this study was to investigate the high-energy metabolism in the calf muscle during incremental progressive plantar flexion exercise of a selected peripheral arterial disease (PAD) patient group. METHODS: Using a 1.5-T whole-body magnetic resonance scanner, 17 male patients with PAD who had 1 symptomatic and 1 asymptomatic leg and 9 healthy male controls underwent serial phosphor 31 (31P) magnetic resonance spectroscopy during incremental exercise at 2, 3, 4, and 5 W. Furthermore, magnetic resonance angiography was performed, and the ankle-brachial pressure index was determined in the patient group. The runoff resistance (ROR) was separately assessed in each patient's leg. RESULTS: The symptomatic legs exhibited significantly increased phosphocreatine (PCr) time constants during the first three workload increments (2-4 W) and the recovery phase compared with the asymptomatic legs and the normal controls. Only two symptomatic legs reached the last increment at 5 W. Compared with the normal controls, the asymptomatic legs showed significantly increased PCr time constants only at 5 W. In the patient group, we detected significant correlations between the PCr time constants and the ROR, as well as the ankle-brachial pressure index. Moreover, the symptomatic legs presented significantly lower PCr levels and pH values at the end of exercise compared with the asymptomatic and control legs. CONCLUSIONS: Our study shows that muscle function in PAD patients can be objectively quantified with the help of 31P magnetic resonance spectroscopy and correlates significantly with hemodynamic parameters such as ROR and ankle-brachial pressure index. Consequently, 31P magnetic resonance spectroscopy seems to be a useful method to monitor the muscle function of PAD patients for evaluation of established therapies or new therapeutic strategies during research trials.
BACKGROUND: The treadmill exercise test is the most important examination of the functional ability of patients with intermittent claudication or leg pain during exercise, but it does not provide any metabolic information in the calf muscle. The purpose of this study was to investigate the high-energy metabolism in the calf muscle during incremental progressive plantar flexion exercise of a selected peripheral arterial disease (PAD) patient group. METHODS: Using a 1.5-T whole-body magnetic resonance scanner, 17 male patients with PAD who had 1 symptomatic and 1 asymptomatic leg and 9 healthy male controls underwent serial phosphor 31 (31P) magnetic resonance spectroscopy during incremental exercise at 2, 3, 4, and 5 W. Furthermore, magnetic resonance angiography was performed, and the ankle-brachial pressure index was determined in the patient group. The runoff resistance (ROR) was separately assessed in each patient's leg. RESULTS: The symptomatic legs exhibited significantly increased phosphocreatine (PCr) time constants during the first three workload increments (2-4 W) and the recovery phase compared with the asymptomatic legs and the normal controls. Only two symptomatic legs reached the last increment at 5 W. Compared with the normal controls, the asymptomatic legs showed significantly increased PCr time constants only at 5 W. In the patient group, we detected significant correlations between the PCr time constants and the ROR, as well as the ankle-brachial pressure index. Moreover, the symptomatic legs presented significantly lower PCr levels and pH values at the end of exercise compared with the asymptomatic and control legs. CONCLUSIONS: Our study shows that muscle function in PAD patients can be objectively quantified with the help of 31P magnetic resonance spectroscopy and correlates significantly with hemodynamic parameters such as ROR and ankle-brachial pressure index. Consequently, 31P magnetic resonance spectroscopy seems to be a useful method to monitor the muscle function of PAD patients for evaluation of established therapies or new therapeutic strategies during research trials.
Authors: Andreas Greiner; Regina Esterhammer; Dietmar Bammer; Hubert Messner; Christian Kremser; Werner R Jaschke; Gustav Fraedrich; Michael F H Schocke Journal: Eur J Appl Physiol Date: 2007-01-06 Impact factor: 3.078
Authors: Justin D Anderson; Frederick H Epstein; Craig H Meyer; Klaus D Hagspiel; Hongkun Wang; Stuart S Berr; Nancy L Harthun; Arthur Weltman; Joseph M Dimaria; Amy M West; Christopher M Kramer Journal: J Am Coll Cardiol Date: 2009-08-11 Impact factor: 24.094
Authors: Eric A Mellon; Seung-Cheol Lee; Stephen Pickup; Sungheon Kim; Steven C Goldstein; Thomas F Floyd; Harish Poptani; E James Delikatny; Ravinder Reddy; Jerry D Glickson Journal: Magn Reson Med Date: 2009-12 Impact factor: 4.668
Authors: Christian Wolf; Sylvia Boesch; Bernhard Metzler; Helga Weirich-Schwaiger; Thomas Trieb; Michael F H Schocke Journal: Mol Imaging Biol Date: 2007-11-14 Impact factor: 3.488
Authors: Regina Esterhammer; Michael Schocke; Olaf Gorny; Lydia Posch; Hubert Messner; Werner Jaschke; Gustav Fraedrich; Andreas Greiner Journal: Mol Imaging Biol Date: 2007-11-14 Impact factor: 3.488