Abstract 4217: Prediction of Acute Coronary Syndrome Using Computed Tomography
Background: Computed tomographic (CT) characteristics of culprit lesions in acute coronary syndrome (ACS) include positive remodeling (PR) and non-calcified plaques with low attenuation (NCP<30HU). Such imaging characteristics have almost always been described by evaluating the lesions that have already resulted in ACS. In a CT study, we identified the characteristics of atherosclerotic lesions which were associated with subsequent development of acute coronary syndrome (ACS).
Methods: 1067 patients who underwent CT angiography were followed for at least 12 months (mean = 28.0±10.6 months; range=12–50 months). The plaque characteristics of lesions resulting in ACS were compared with those not resulting in ACS.
Results: Twenty-six patients developed ACS after CT examination. Of these, 15 patients could be evaluated the culprit lesions. Of 1067 patients, 72 demonstrated plaque characteristics suggestive of vulnerable plaque; 45 plaques demonstrated both PR and NCP<30HU (probably vulnerable); 27 had either PR or NCP<30HU (possibly vulnerable). Eight-hundred twenty patients did not demonstrate either of these characteristics (probably stable). Ten of 45 who had both PR and NCP<30HU developed ACS (22.2%), 1 had either PR or NCP<30HU (3.33%). Four of 820 patients with no PR or NCP<30HU (0.49%) developed ACS. PR and/or NCP<30HU was detected in 61 patients without subsequent development of ACS. Cox regression analysis was performed using 9 variables including age, gender, hypertension, hyperlipidemia, diabetes mellitus, obesity, smoking, prior myocardial infarction, and the presence of probably or possibly vulnerable plaques; the presence of probably or possibly vulnerable plaques was significant independent predictor of ACS (Hazard Ratio 14.38, p<0.001). There was significant increase in occurrence of ACS in patients with probably or possibly vulnerable plaques than patients without these plaque characteristics (15.3% vs 0.4%, loglank test p<0.001)
Conclusions: The CT-based atherosclerotic plaque characteristics responsible for subsequent ACS include NCP<30HU and positive remodeling; the presence of such plaques strongly predict development of ACS in patients with coronary artery disease.