Abstract 709: Coronary Artery Spatial Distribution, Morphology, and Composition of Non-culprit Vulnerable Plaques by 64-slice Computed Tomography Angiography in Patients With Acute Myocardial Infarction
Non-invasive identification of non-culprit lesions may improve risk stratification after AMI. We assessed morphology, composition, and spatial distribution of non-culprit vulnerable plaques in patients with acute myocardial infarction (AMI) by computed tomography angiography (CTA).
Methods: Sixty-four patients with AMI underwent 64-slice CTA within 2 week after admission, and 162 symptomatic patients with stable angina pectoris (SAP) underwent 64-slice CTA and stress myocardial perfusion imaging (MPI).
Results: Of these 226 patients, 16 were excluded from analysis due to image artifacts. Mean number of non-culprit coronary plaques per patient was 5.0±2.6 in the AMI group (n=60), 4.2±2.6 in the SAP group with abnormal MPI (n=67), and 1.1±1.3 in the SAP group with normal MPI (n=83) (p<0.0001). Mean number of vulnerable plaques, defined as low CT density (<30 Hounsfield Units) and positive remodeling, was 1.9±1.8 in the AMI group, 0.6±0.9 in the SAP group with abnormal MPI, and 0.2±0.4 in the SAP group with normal MPI (p<0.0001). (Figure A⇓) Within the AMI group specifically, the number of vulnerable plaques was significantly higher in patients with metabolic syndrome than in those without (2.6±2.2 vs 1.4±1.4, p=0.03), and vulnerable plaques were more frequently distributed in the proximal segments of the left anterior descending artery (p<0.0001). (Figure B⇓)
Conclusions: Sixty-four-slice CTA may noninvasively provide promising information on risk stratification of AMI for preventive strategies by identifying coronary plaque morphology and zones at high risk for future events.