Background:
Several studies have reported that echo-attenuated plaque (EA) on intravascular ultrasound (IVUS) was related to poor outcomes after percutaneous coronary intervention (PCI) in acute coronary syndrome. However, its clinical significance and influence on outcomes in patients with stable angina pectoris (SAP) has not been fully clarified. We investigated relationships of EA on IVUS with other plaque morphologies and outcomes after PCI in SAP patients.
Methods:
We investigated 127 de-novo lesions in 127 SAP patients with normal pre-PCI cardiac troponin-T level (cTnT <0.014ng/ml), who underwent pre-PCI IVUS and optical coherence tomography (OCT) examination. All lesions were divided into lesions with and without EA on IVUS. The occurrence of periprocedural myocardial infarction (PMI) was defined by elevation of cTnT level at 24h after PCI ≥5 times the upper limit of normal range. Plaque morphologies on IVUS and OCT were compared between the two groups. Further, we investigated the independent predictors for occurrence of PMI by multivariate analysis.
Results:
EA was observed in 34 (26.8%) lesions. Lesions with EA had greater vessel area (15.8±4.9 vs. 12.7±4.0 mm2, p=0.002), plaque burden (83.9±7.2 vs. 78.6±8.6%, p<0.001) and remodeling index (1.19±0.25 vs. 1.00±0.24, p<0.001) on IVUS than those without EA. OCT analysis showed greater lipid arc (213±80 vs. 155±99 degree, p=0.001), thinner fibrous cap thickness (182±109 vs. 231±114 μm, p=0.03), higher frequency of thin-cap fibroatheroma (23.5 vs. 7.5%, p=0.03), and white thrombus (29.8 vs. 9.7%, p=0.004) in lesions with EA. Lesions with EA had calcified plaques with smaller arc (92.6±45.4 vs. 144±88 degree, p=0.005) and thinner thickness (388±151 vs. 623±265 μm, p<0.001) on OCT than those without EA. Multivariate analysis including clinical, lesion characteristics and procedural results revealed that EA on IVUS remained an independent predictor for PMI (odds ratio 4.49, 95% confidence interval 1.72-11.73, p=0.002).
Conclusions:
In SAP lesions, presence of EA on IVUS may suggest the existence of unstable plaque compositions and may predict for occurrence of PMI.
CRT-100.05 Tissue Characteristics of Culprit Coronary Lesions in Acute Coronary Syndrome and Target Coronary Lesions in Stable Angina Pectoris Using Virtual Histology and Intravascular Ultrasound
