Coronary wall characteristics after myocardial infarction without significant coronary angiographic lesion: an intravascular ultrasound study.

ABSTRACT

AIM: Coronary of angiography may be normal or without significant lesion after myocardial infarction (MI) in about 10% of cases. Our aim was to evaluate intravascular ultrasound (IVUS) findings, mainly remodelling, in patients with normal or near normal angiography early after MI. METHODS AND RESULTS: We prospectively included 17 patients, admitted for STEMI or non-STEMI with no lesion > 30% (QCA) on early coronary angiography. Culprit vessel was defined by evidence of a thrombus in a proximal segment, distal embolization or focal akinesia of the left ventricle. Negative remodelling (NR) was defined as a remodelling index (lesion/reference external elastic membrane cross sectional area [CSA]) < 0.95, no remodelling as between 0.95-1.05, and positive remodelling (PR) as > 1.05. IVUS could identify a short, single, minor, eccentric and hypoechogenic lesion in all patients, of proximal location in 76.4% cases. PR was observed in only 1 patient (5.9%). CONCLUSION: A discrete lesion was observed in all patients with apparently normal arteries. Although previous reports have shown an association between PR and vulnerability, in our study PR was unusual. Our study supports the hypothesis that in some patients, vulnerability may appear very early in the natural history of coronary artery disease before any vessel remodelling.