Abstract 1636: Computed Tomography Characteristics of Atherosclerotic Plaques Subsequently Resulting in Acute Coronary Syndrome
Background: The imaging characteristics of vulnerable plaques have almost always been described by evaluating the lesions that have already resulted in acute coronary syndrome (ACS). In contrast, we identified the computed tomography (CT) characteristics of atherosclerotic lesions which were associated with subsequent development of ACS. In our previous study, CT characteristics of culprit lesions in ACS included positive remodeling(PR) and soft plaques(SP) with low attenuation (<30HU).
Methods: 1154 patients underwent CT angiography followed for at least 12 month (range 12–51). The presence of PR and SP were evaluated in all patients. Plaques in patients with either PR or SP were characterized for plaque volume and consistency using Sure Plaque software (Toshiba Medical Systems); lesions with previous percutaneous coronary intervention (PCI) and target lesion for elective PCI were excluded. The plaque characteristics of lesions resulting in ACS (ACS+) were compared with those not resulting in ACS (ACS−).
Results: Ten of 1154 patients suffered from ACS after CT. Of these, 7 had PR and 6 had SP; 8 had either PR or SP. Two patients with no PR or SP, demonstrated large calcification. PR or SP was detected in 54 patients without subsequent development of ACS. Total plaque volume(291.9±269.0 vs 152.8±78.5mm3, p=0.0022), soft plaque volume (26.0±50.0 vs 3.7±6.4mm3, p=0.0020), maximum soft plaque area in cross sectional images (4.7±5.6 vs 1.3±1.7mm2, p=0.0004) was significantly larger in ACS(+) group than ACS(−) group.
Conclusions: The CT characteristics of the lesions responsible for subsequent ACS include larger plaque volume, and larger soft plaque area and volume.