Structural alterations of the coronary arterial wall are associated with myocardial flow heterogeneity in type 2 diabetes mellitus.
OBJECTIVE
To determine the relationship between carotid intima-media thickness (IMT), coronary artery calcification (CAC), and myocardial blood flow (MBF) at rest and during vasomotor stress in type 2 diabetes mellitus (DM).


METHODS
In 68 individuals, carotid IMT was measured using high-resolution vascular ultrasound, while the presence of CAC was determined with electron beam tomography (EBT). Global and regional MBF was determined in milliliters per gram per minute with (13)N-ammonia and positron emission tomography (PET) at rest, during cold pressor testing (CPT), and during adenosine (ADO) stimulation.


RESULTS
There was neither a relationship between carotid IMT and CAC (r = 0.10, p = 0.32) nor between carotid IMT and coronary circulatory function in response to CPT and during ADO (r = -0.18, p = 0.25 and r = 0.10, p = 0.54, respectively). In 33 individuals, EBT detected CAC with a mean Agatston-derived calcium score of 44 +/- 18. There was a significant difference in regional MBFs between territories with and without CAC at rest and during ADO-stimulated hyperemia (0.69 +/- 0.24 vs. 0.74 +/- 0.23 and 1.82 +/- 0.50 vs. 1.95 +/- 0.51 ml/g/min; p < or = 0.05, respectively) and also during CPT in DM but less pronounced (0.81 +/- 0.24 vs. 0.83 +/- 0.23 ml/g/min; p = ns). The increase in CAC was paralleled with a progressive regional decrease in resting as well as in CPT- and ADO-related MBFs (r = -0.36, p < or = 0.014; r = -0.46, p < or = 0.007; and r = -0.33, p < or = 0.041, respectively).


CONCLUSIONS
The absence of any correlation between carotid IMT and coronary circulatory function in type 2 DM suggests different features and stages of early atherosclerosis in the peripheral and coronary circulation. PET-measured MBF heterogeneity at rest and during vasomotor stress may reflect downstream fluid dynamic effects of coronary artery disease (CAD)-related early structural alterations of the arterial wall.
Schindler
Thomas H
TH
Department of Molecular and Medical Pharmacology, Radiological Science, David Geffen School of Medicine, University of California at Los Angeles, 10833 Le Conte Avenue, 23-120 CHS, P.O. Box 173517, Los Angeles, CA 90095-1735, USA.
Facta
Alvaro D
AD
Prior
John O
JO
Cadenas
Jerson
J
Zhang
Xiao-Li
XL
Li
Yanjie
Y
Sayre
James
J
Goldin
Jonathan
J
Schelbert
Heinrich R
HR
D000241:Adenosine / Q000494:pharmacology; D000328:Adult; D002114:Calcinosis; D002339:Carotid Arteries / Q000473:pathology / Q000503:physiopathology; D003080:Cold Temperature; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D012146:Rest; D013564:Sympathetic Nervous System / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
D000241:Adenosine