Myocardial insulin resistance does not always parallel skeletal muscle and whole body insulin resistance: A mini review —Myocardial Insulin Resistance

Insulin resistance (IR) is recognized to be of critical importance in a variety of metabolic diseases and coronary artery disease (CAD). Impaired skeletal muscle glucose utilization (SMGU) plays an important role in the pathogenesis of IR, whereas it is controversial whether myocardial IR is similar in this respect. Methods: Twenty-two studies of myocardial IR and skeletal muscle IR using positron emission tomography (PET) and/or whole body IR were reviewed. Heart and skeletal muscle IR were measured with PET and18F-FDG under hyperinsulinemic euglycemic insulin clamp technique. Whole body IR was also determined at the time of PET under hyperinsulinemic euglycemic insulin clamp technique. Results: One study reported that heart and skeletal muscle IR is present in untreated type 2 diabetes mellitus (T2DM), hypertension and CAD (as reflected in a myocardial glucose utiliation rate (MGU) in T2DM vs control [p -0.665, p -0.60, p -0.74, p -0.74, p 18F-FDG Uptake (MFU) in hypertriglyc-eridemics was (p = ns) despite findings of reduced skeletal muscle18F-FDG uptake (SMFU in hyper-triglyceridemia (p