Abstract 17884: The Association Between Prior Aspirin Use and Optical Coherence Tomography Findings in Acute Coronary Syndromes
Backgrounds: Aspirin has been shown to be beneficial in the primary prevention, secondary prevention, and treatment of acute coronary syndromes (ACS). However, it is less clear whether aspirin therapy affects lesion morphology in ACS or benefits patients who develop ACS despite its use. We assessed the hypothesis that prior aspirin use affects the baseline patient characteristics, type of acute coronary syndrome, and the culprit lesion morphology examined by optical coherence tomography (OCT) in ACS patients.
Methods and Results: We studied 252 ACS patients with identifiable 252 native de novo culprit lesions who underwent OCT examinations before PCI. Patients were excluded if they had significant left main disease, severe congestive heart failure, or cardiogenic shock. Clinical and OCT findings were compared between the two groups divided on the basis of prior aspirin use (ASA; n= 51: 20%, non-ASA; n = 201: 80%). TCFA was defined as lipid-rich plaque (one or more quadrants) with fibrous cap thickness < 70μ m.The frequency of hypertension (ASA: 82% vs non-ASA: 63%, P = 0.01), history of previous PCI (49% vs 2%, P < 0.001), previous myocardial infarction (24% vs 3%, P < 0.001), non-ST-segment elevation ACS (75% vs 55%, P = 0.01), higher levels of cholesterol and increased white blood cell count were more frequent in ASA group than in non-ASA. Frequency of coronary occlusion at initial angiogram was similar in both groups (ASA: 16% vs non-ASA: 25%, P = 0.19). In OCT analysis, the presence of thrombi (53% vs. 73%, P = 0.01) and plaque rupture (26% vs. 41%, P = 0.04) were significantly less frequent in ASA group, whereas there were no significant differences in frequency of TCFA (51% vs. 62%, P = 0.16), thinnest cap thickness (median: 60 µm [IQR: 50-100] vs. 60 µm [50-80], P = 0.63), and lipid quadrants (median: 3 [IQR: 2-4] vs. 3 [3-4], P = 0.66) between the two groups. No significant difference in in-hospital major adverse cardiac event including death, re-revascularization, fatal arrhythmia, bleeding complication, and congestive heart failure was observed between the two groups (28% vs 20%, P = 0.28).
Conclusions: ACS patients with prior aspirin use are a high risk population, yet have less severe clinical presentation and OCT-defined less unstable lesion characteristics.
- © 2012 by American Heart Association, Inc.