Abstract 15902: Assessment of Nonculprit Vulnerable Plaque by 64-Slice Multidetector Computed Tomography in Comparison to Intravascular Ultrasound

Abstract

«Background» Coronary atherosclerotic plaque composition plays an important role in the progression of future coronary event. Especially, coronary atherosclerotic plaque with intravascular ultrasound (IVUS) attenuation might be related to the deterioration of coronary flow and worse long-term outcomes after coronary heart disease (CHD) and interventions. Noninvasively characterizing vulnerable plaque is an important method in risk stratification and following the progression of coronary plaques. Multidetector computed tomography (MDCT) is most reliable method to evaluate coronary plaque composition. The aim of this study is to evaluate possibility of 64-slice MDCT to detect nonculprit attenuated plaque derived by IVUS and identification of atherosclerotic plaque with future coronary events. «Methods and Results» Fifty-seven patients(15 with ACS, 42 with stable CHD) and 240 plaques were evaluated by 64-slice MDCT. One hundred sixty-eight nonculprit plaques of the 240 plaques were evaluated by IVUS. Of the 168 plaques, 59 (47 calcified and 12 mixed plaques) were excluded from the present analysis. The remaining 109 plaques (40 soft plaques, 30 attenuated plaques, 39 fibrous plaques) represent the present analysis. In the attenuated plaques, CT density had significantly higher than soft plaques (70 ± 9 HU vs 40 ± 6 HU; p < 0.001) and lower than fibrous plaques (70 ± 9 HU vs 94 ± 6 HU; p < 0.001). Spotty calcification with lipid pool was more common (37 % vs 13 %; p < 0.05) in the attenuated plaques compared to the soft plaques. The attenuated plaques were present significantly more frequently in patients with lower high-density lipoprotein cholesterol levels than those without attenuated plaques (40 ± 9 mg/dl vs 48 ± 9 mg/dl; p < 0.001, 40 ± 9 mg/dl vs 47 ± 11 mg/dl; p < 0.005). «Conclusions» Nonculprit plaque analysis by MDCT would be a useful method for predicting atherosclerotic plaque with high risk of future coronary events.