[Circulatory function test for the diagnosis of diabetic complications]

Diabetic patients suffer from systemic complications, which are generally characterized by a lack of early symptoms. In the management of diabetes, early diagnosis of complications and preventing progression are of importance. Vascular complications of diabetes are divided into microvascular and macrovascular complications. Circulatory function tests play a major role in diagnosing the presence and severity of macrovascular complications in clinical settings. In this review, we outlined the significance and precautions of each test in the diagnosis of diabetic macrovascular disease. 1) Echocardiography: Diabetic patients are often associated with ischemic heart disease, and some patients present with diffuse wall motion abnormalities due to multivessel disease. Patients with diabetic cardiomyopathy may have signs of left ventricular diastolic dysfunction with normal systolic function. 2) Carotid ultrasonography: Increase in intima-media thickness is associated with the onset of cardiovascular and cerebrovascular disease. Hypoechoic plaque and the thrombus formation have been reported to be closely related with cerebral infarction. 3) Assessment of lower extremity artery: Patients with diabetes are at a higher risk of developing peripheral artery diseases (PAD), which lead to disability. Doppler ultrasonography is widely used for noninvasive diagnosis of PAD. Information of real-time physiological blood flow is useful for disease monitoring. 4) Ankle-brachial index (ABI): ABI is a simple method recommended for screening and evaluating PAD of lower limbs. The limitation of this measurement is that pseudonormalization may occur with severe calcification of artery walls. 5) Pulse wave velocity (PWV), flow-mediated dilatation (FMD): PWV and FMD provide information for the function of blood vessels. Functional changes in peripheral arteries may precede structural changes. In this regard, these tests may play an important role in early diagnosis.