Abstract 2500: Acute Myocardial Infarction Without Disrupted Yellow Plaque Among Patients Below 50 Years Old - Angioscopic Study
Background: Thrombosis caused by the disruption of atherosclerotic plaque is generally regarded as the cause of acute myocardial infarction (MI). However, it has not been clarified if young patients also have the same pathophysiology with advanced plaque formation. Therefore, we examined the culprit lesion of young acute MI patients with angioscopy.
Methods: Among a series of patients (n=893) who received catheterization for acute MI, clinical characteristics were compared between young patients <50 years (n=66) and the rest of patients. Angoscopic appearance of culprit lesions was evaluated among 20 young patients in whom angioscopic examination was successfully performed. Among them, clinical characteristics were compared between those who had disrupted yellow plaque with thrombus (dYP&T) and those who did not have it.
Results: Patients <50 years had higher prevalence of smoking (68% vs. 48%, p=0.01), obesity (43% vs. 15%, p=50 years. dYP&T was detected at culprit lesion in 14 (70%) patients. Patients <50 years with dYP&T and those without it did not have different clinical characteristics except that those without dYP&T were younger. Prevalence of dYP&T were lower in patients <40 years (44% vs. 91%, p=0.02) than those between 40 and 50 years. Patients <40 years and those between 40 and 50 years did not have different clinical characteristics except that those <40 years had trend for higher prevalence of smoking (88% vs. 62%, p=0.05).
Conclusion: Young acute MI patients <50 years, especially <40 years, had lower prevalence of dYP&T but higher prevalence of smoking, obesity, and hypercholesterolemia, suggesting that vulnerable blood rather than vulnerable plaque would play an important role for the onset of MI.