Carotid atherosclerotic plaque instability in patients with acute myocardial infarction.
The instability of atherosclerotic plaque is partly determined by local factors, but systemic factors such as infection, inflammation, autoimmunity or genes might also be important. We aimed to analyze whether patients with acute myocardial infarction (AMI) might have a higher proportion of unstable plaques in the carotid arteries compared with patients who had had no acute coronary events.


METHODS
Sixty-nine consecutive patients with AMI (Group 1) and 95 patients without acute coronary events (Group 2) had carotid artery duplex ultrasounds. Carotid atherosclerosis was quantified by number of plaques in the two carotid arteries, intimal media thickening and degree of maximal stenosis. According to their morphology, plaques were divided into stable (fibrocalcific) and unstable (soft and/or not homogeneous).


RESULTS
The two groups did not differ as regards age (66+/-8 vs. 68+/-19; p=0.3), female sex (13% vs. 21%; p=0.3), mean number of carotid plaques (2.8+/-1 vs. 2.5+/-2; p=0.2), degree of stenosis (59+/-2% vs. 36+/-1%; p=0.2) or intimal media thickening (1.04+/-0.2 vs. 1.06+/-0.2; p=0.8). However, Group 1 pts more frequently had unstable carotid plaques compared with Group 2 (43% vs. 15%; p=0.004), and had a greater number of unstable carotid plaques (0.51+/-0.6 vs. 0.16+/-0.4: p<0.0001) and a higher ratio of unstable to stable plaque (19% vs. 8%; p=0.005). In the overall population, logistic regression analysis showed that after adjustment for degree of maximal stenosis, the presence of coronary artery event (AMI pts) predicted the presence of unstable carotid plaque (OR: 4.3 95% CI: 2.0-9.2; p=0.0002).


CONCLUSIONS
Patients with unstable coronary artery disease expressed clinically as AMI, frequently had unstable atherosclerotic plaques in other arterial sites such as carotid arteries. This finding supports the hypothesis that plaque instability might reflect a systemic process.
Rossi
Andrea
A
Dipartimento di Scienze Biomediche e Chirurgiche, Sezione di Cardiologia, University of Verona, Verona, Italy. andrea.rossi@univr.it
Franceschini
Lorenzo
L
Fusaro
Massimilano
M
Cicoira
Mariantonietta
M
Eleas
Alejandra Amado
AA
Golia
Giorgio
G
Bonapace
Stefano
S
Santini
Francesco
F
Sangiorgi
Giuseppe
G
Zardini
Piero
P
Vassanelli
Corrado
C
D000368:Aged; D000369:Aged, 80 and over; D002339:Carotid Arteries / Q000000981:diagnostic imaging; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology*; D012307:Risk Factors; D014463:Ultrasonography