Echolucency of the carotid artery is associated with short-term plaque progression and positive remodeling in the culprit coronary artery in AMI survivors.

BACKGROUND: Rapid plaque progression and positive remodeling are recognized as vulnerable coronary plaque characteristics. This study examined whether serial carotid ultrasonography might be of value for assessment of coronary plaque progression and positive remodeling, measured by serial intravascular ultrasound (IVUS), in survivors of acute myocardial infarction (AMI).

METHODS: Thirty-nine patients with AMI had repeated examinations by IVUS of culprit coronary arteries and echolucency of the coronary artery on admission (1st test) and 6 months later (2nd test). Plaque volume and external elastic membrane area of the native segment (15±9mm in length) beginning 5mm proximal to the stent edge in the culprit coronary artery were measured using volumetric IVUS. Echolucency of the carotid artery was assessed by integrated backscatter (IBS) analysis. Lower IBS reflects an echolucent and lipid-rich plaque.

RESULTS: Increase in coronary plaque volume and positive remodeling over 6 months occurred in 17 and 12 patients, respectively. The % change in carotid IBS value over 6 months was correlated with the % change in the coronary plaque volume (r=-0.69, p<0.001). The aggravated change in the carotid IBS was significantly associated with increase in the coronary plaque volume and positive remodeling over 6 months (OR 0.94 and 0.95, respectively, 95% CI 0.90-0.99, both p<0.05).

CONCLUSIONS: Serial measurements of echolucency of the carotid artery may be of value for assessment of short-term progression and positive remodeling of coronary plaques in AMI survivors.