Optimum Hypoglycemic Therapy can Improve Coronary Flow Velocity Reserve in Diabetic Patients-Demonstration by Transthoracic Doppler Echocardiography-

Abstract

iabetes mellitus (DM) is a major independent risk factor for coronary artery disease 1,2 and such patients show not only atherosclerosis of the major epicardial coronary arteries, but also microvascular dysfunction in accordance with disease severity and duration. 3 The progression of abnormalities in the coronary circulation is associated with reduced coronary flow reserve (CFR), and may produce myocardial ischemia, even in the absence of angiographically significant coronary artery stenosis. 4,5 Hyperglycemia is known to be a pivotal factor for the development of vascular abnormalities, which might be account for the reduction in CFR in diabetic patients. 6,8,9 The current methods for measuring CFR are only available in the cardiac catheterization laboratory (eg, Doppler guidewire) or a very few cardiovascular centers (eg, positron emission tomography), and thus are not used for the general diabetic population. Several recent studies have shown that coronary flow velocity (CFV) in the distal part of the left anterior descending coronary artery (LAD) can be successfully measured by transthoracic Doppler echocardiography (TTDE), and the measurement of coronary flow velocity reserve (CFVR) with adenosine or dipyridamole has been shown to be a useful index for detecting functionally significant LAD stenosis. [10][11][12] method also may be useful for the serial assessment of CFVR in the same patients. It is uncertain whether or not coronary microvascular dysfunction in diabetic patients is irreversible with hypoglycemic therapy. We hypothesized that the elimination of hyperglycemia would accompany the improvement of CFVR. To determine this, we performed the serial assessment of CFVR by TTDE before and after intensive antidiabetic treatment in poorly controlled diabetic patients. Methods PatientsThe study group comprised 54 consecutive poorly controlled type II diabetic patients who on admission to hospital had required intensive antidiabetic treatment for their high blood glucose concentration. Poorly controlled diabetes was defined as a fasting blood glucose (FBG) concentration >150 mg/dl. None of the patients had a definite history of coronary artery disease or wall motion abnormality on 2-dimensional echocardiography. Their mean age was 62±12 years (30 men, 24 women). Twelve patients had new onset of diabetes and the other 42 had a history of antidiabetic treatment in the outpatient clinic for a mean of 8±9 years. Seventeen type II diabetic patients with well controlled blood glucose (FBG <150 mg/dl) who were admitted to hospital for other reasons served as the control group (mean age, 63±11 years; 10 men, 7 women). ProtocolThe ethics committee of the hospital approved the study protocol, and informed consent was obtained from all Circ J 2003; 67: 945 -950 (Received November 18, 2002; revised manuscript received August 11, 2003; accepted August 20, 2003

Effects of non-supervised low intensity aerobic excise training on the microvascular endothelial function of patients with type 1 diabetes: a non-pharmacological interventional study

“…In spite of the positive effects of anti-hyperglycemic therapy [ 13 ] and drugs that attenuate inflammation and oxidative stress [ 14 ], chronic aerobic exercise has been shown to exert anti-inflammatory, anti-hyperglycemic and anti-oxidant effects [ 15 ]. Moreover, exercise training contributes to an increase in capillary density in patients with T1D [ 16 ].…”

Coronary Microvascular Function and Beyond: The Crosstalk between Hormones, Cytokines, and Neurotransmitters

“…This result suggests that acute hyperglycemia may have adverse effects on coronary microcirculation. Instead, control or improvement of hyperglycemia improves CFR, as shown in poorly controlled diabetic patients [65]. …”