138 Relationship between coronary calcification and endothelium dependent coronary vaso-reactivity in asymptomatic diabetic patients without overt coronary artery disease

Abstract

Methods We studied 23 (mean age 63 ± 10, 19 M, 4 F) patients with type II DM, without history, symptom or ECG evidence of CAD. The subjects underwent 1-day rest-stress adenosine nuclear stress test, assessment of coronary calcification by EBCT and absolute measurement of myocardial blood flow at rest (MBF-R), and following cold-water hand immersion for 1 minute (MBF-C). All imaging studies were performed within 24 hours. Flow measurements by CMRI was performed using saturation recovery TurboFLASH imaging sequence: TR/TE/TI/FA = 2.9 ms/1.3 ms/ 90 ms/6°, data matrix 128 × 70, and usual voxel spatial resolution 3.5 × 1.9 × 8 mm3. Contrast dose was 0.05 mmol/kg (Omniscan, Amersham). All scans were processed in a blinded fashion. Using Medis software (Leiden University, the Netherlands), basal, mid-cavity and apical slices were divided into 6 equal transmural sectors. After correction for coil sensitivity variations, model independent deconvolution of myocardial signal intensity curves in the sectors, with blood pool signal intensity curves was performed. MBF-R and MBF-C in mls/g/min were determined. Endothelium dependent perfusion reserve (MPR) in these sectors were calculated as the ratios of MBF-C to MBF-R in each sector. The sectors wre subsequently grouped based on standard coronary vascular distribution.