Abstract 12787: Correlation Between Optimal Glycemic Control and Coronary Flow Reserve in Patients With Type 2 Diabetes Mellitus
Introduction: Patients with type-2 diabetes mellitus are known to have coronary microvascular dysfunction, also before obstructive coronary artery disease. Doppler-derived coronary flow velocity (CFV) and coronary flow reserve (CFR) can be useful to assess early microvascular dysfunction in these patients. Diastolic-to-systolic peak Doppler velocity ratio (DSVR) of basal coronary flow is a simple method to assess the severity of coronary artery stenosis. On the other hand, transthoracic Doppler-derived CFR is an index of coronary arterial reactivity and decreases in both microvascular dysfunction and coronary artery stenosis. It is known to provide independent prognostic information in diabetic patients.
Hypothesis: The aim of our study was to assess the relationship between glycosylated haemoglobin (HbA1c) and both DSVR and CFR in type 2 diabetes mellitus patients, using transthoracic Doppler echocardiography.
Methods: We prospectly enrolled 74 patients (48M, 26F, mean age 68±9 years) with type 2 diabetes mellitus, without signs or symptoms of myocardial ischemia. All patients underwent measurement of HbA1c and, within 3 days, complete transthoracic echocardiography. Noninvasive assessment of DSVR and CFR of the left anterior descending coronary artery was performed using an ultrasound system (Vivid 7, GE Medical Systems). CFR were determined as the ratio of hyperemic, induced by intravenous dypiridamole administration, to baseline diastolic coronary flow velocity.
Results: Patients were classified in two groups, if their HbA1c levels were higher or lower than 7%. HbA1c was > 7.0% in 32% patients. There were no differences in described clinical characteristics between the two groups. Patients with HbA1c > 7.0% showed CFR values significantly lower than patients with HbA1c ≤ 7.0 (2.07±0.38 vs 2.41±0.42 p<0.01). Moreover, HbA1c showed a significant correlation with coronary flow reserve (r - 0.48 p<0.01). No correlation was found between HbA1c and DSVR.
Conclusions: Optimal glycemic control (defined as HbA1c ≤ 7%) is associated with better microvascular dysfunction, with improved preservation of CFR as determined by Doppler echocardiography. There is no correlation, instead, between HbAc1 and basal coronary flow, assessed by DSVR.
Author Disclosures: E. Tagliamonte: None. F. Rigo: None. T. Cirillo: None. A. Caruso: None. C. Astarita: None. G. Cice: None. G. Quaranta: None. C. Romano: None. N. Capuano: None. R. Calabrò: None.
- © 2014 by American Heart Association, Inc.