Different Plaque Composition and Progression in Patients with Stable and Unstable Coronary Syndromes Evaluated by Cardiac CT.
OBJECTIVE
To compare the quantity, subtype, and progression of atherosclerosis by cardiac computed tomography (CT) and intravascular ultrasound (IVUS) in patients with stable (SAP) and unstable angina pectoris or non-ST-elevation myocardial infarction (UAP/n-STEMI).


METHODS
Forty patients with SAP and 20 with UAP/n-STEMI underwent cardiac CT and angiography with IVUS at baseline and after one year. Atherosclerotic segments were divided into calcified, mixed, or noncalcified subtypes, and significant stenoses were registered.


RESULTS
Thirty-two SAP and 15 UAP/n-STEMI patients completed the CT follow-up. At baseline, the number of atherosclerotic segments was higher in UAP/n-STEMI than in SAP (P = 0.039). UAP/n-STEMI patients had more segments with noncalcified plaques (P = 0.0005) whereas SAP patients had more segments with calcified plaques (P = 0.013). The number of segments with significant stenosis did not differ between the groups, but noncalcified plaques more frequently caused significant stenoses in UAP/n-STEMI than in SAP patients (P = 0.0002). After one year the number of segments with atherosclerosis increased in SAP patients (P = 0.0001). The number of atherosclerotic segments remained unchanged in UAP/n-STEMI patients. However, composition was altered as the number of segments with noncalcified plaques decreased (P = 0.018). IVUS data confirmed the CT findings.


CONCLUSIONS
Quantity, subtype, and progression of atherosclerosis differ between SAP and UAP/n-STEMI patients.
Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
Maiken Glud
MG
Dalager
Cardiac Imaging Center, Hospital Unit Vest, Gl. Landevej 61, 7400 Herning, Denmark.
Morten
M
Bøttcher
Department of Biomedical Engineering, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
Jesper
J
Thygesen
Department of Radiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
Gratien
G
Andersen
Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
Hans Erik
HE
Bøtker
D000368:Aged; D060050:Angina, Stable / Q000000981:diagnostic imaging / Q000503:physiopathology*; D000789:Angina, Unstable / Q000000981:diagnostic imaging / Q000503:physiopathology*; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology*; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional