Distinct Arterial Remodeling in Young Patients with AMI
Younger acute myocardial infarction patients more likely to have 'constrictive' remodeling, higher cholesterol and higher body mass index
THURSDAY, Dec. 27 (HealthDay News) -- Younger Japanese patients with acute myocardial infarction (AMI) were more likely to have a constrictive type of arterial remodeling as the culprit atherosclerotic lesion than middle-aged and older patients, researchers report in the Dec. 15 issue of the American Journal of Cardiology.
Shoichi Ehara, M.D., of the Osaka City University Graduate School of Medicine in Japan, and colleagues analyzed intravascular ultrasound images of 96 AMI patients. They divided them into three groups: young (55 years or younger), middle-aged (56 to 69 years) and old (aged 70 or older). To define expansive and constrictive remodeling, the researchers used a ratio of the external elastic membrane area of the culprit lesion to the area at a nearby reference site.
Constrictive remodeling, which has been associated with early plaque progression, was more common in younger patients. Expansive remodeling, which has been related to calcific deposits, occurred most often in the middle-aged and old patients. In addition, total cholesterol, low-density lipoprotein cholesterol, triglycerides and body mass index were higher in the young group compared with the old group.
"Previous studies have demonstrated that a greater incidence of plaque erosion is noticed in younger patients and that plaque erosion results in constrictive remodeling. In contrast, it has been demonstrated that expansive remodeling is associated with plaque rupture with a large lipid core," the authors write. "One may speculate that the differences in arterial remodeling of the coronary culprit lesion between younger and older patients with acute myocardial infarction may reflect different biologic mechanisms of plaque activation and destabilization."