Microvascular lesions is one of the main pathological mechanisms of diabetic cardiomyopathy. The micrangium and the "collateral" of TCM in terms of structure, physiology and function were compared to search the rele-vance of microvascular disease with "persistent illness entering collaterals" pathogenesis of TCM. Microvascular disease can be attributed to the category of "collateral disease" of TCM, thus diabetic cardiomyopathy has the characteristics of "persistent ill-ness entering collaterals" pathogenesis. This conclusion can pro...