摘要：Impaired oxidative metabolism is one of multi-variate factors leading to exercise intolerance in heart failure patients. The purpose of the study was to demonstrate the use of dynamic
31P magnetic resonance spectroscopy (MRS) and
31P magnetic resonance imaging (MRI) techniques to measure PCr resynthesis rate post-exercise as a biomarker for oxidative metabolism in skeletal muscle in HF patients and controls. In this prospective imaging study, we recruited six HF patients and five healthy controls. The imaging protocol included
31P-MRS, spectrally selective 3D turbo spin echo for
31P-MRI, and Dixon multi-echo GRE for fat–water imaging on a 3 T clinical MRI scanner. All the subjects were scanned pre-exercise, during plantar flexion exercise, and post-exercise recovery, with two rounds of exercise for
31P -MRS and
31P-MRI, respectively. Unpaired t-tests were used to compare
31P-MRS and
31P-MRI results between the HF and control cohorts. The results show that PCr resynthesis rate was significantly slower in the HF cohort compared to the controls using
31P-MRS (
P = 0.0003) and
31P-MRI (
P = 0.0014).
31P-MRI showed significant differences between the cohorts in muscle groups (soleus (
P = 0.0018), gastrocnemius lateral (
P = 0.0007) and gastrocnemius medial (
P = 0.0054)). The results from this study suggest that
31P-MRS/
31P-MRI may be used to quantify lower leg muscle oxidative metabolism in HF patients, with
31P-MRI giving an additional advantage of allowing further localization of oxidative metabolism deficits. Upon further validation, these techniques may serve as a potentially useful clinical imaging biomarker for staging and monitoring therapies in HF-patients.
