Coronary stenosis severity linked to infarct-related lesions in acute MI
MedWire News: Stenosis severity and infarct-related lesions (IRLs) are significantly associated in patients with ST-segment elevation myocardial infarction (STEMI), an Australian study has found.
Stenosis severity is also strongly related to compression coronary artery movement (CAM).
There have been conflicting findings on the relationship between stenosis and IRLs, while the relationship between CAM type and IRLs is largely unknown, say Kim Chan from Royal Prince Alfred Hospital in Sydney, and colleagues.
To investigate these relationships, the team performed quantitative coronary angiography, and determined CAM pattern and extent score (atheroma burden) for each coronary artery segment in 203 STEMI patients after successful fibrinolysis.
IRL stenosis was at least moderate (>50%) and severe (>70%) in 78% and 31% of patients, respectively. Culprit arteries were associated with significantly higher atheroma extent scores (25.2 vs 21.6, p<0.001).
Analysis of 2228 coronary segments showed a strong correlation between stenosis severity and IRLs. Indeed, culprit segments were significantly more likely to occur in patients with severe stenosis than in those with mild stenosis (<30%), at an odds ratio (OR) of 30.0 (p<0.001).
The likelihood of a coronary segment having compression CAM also progressively increased with worsening stenosis, at an OR of 56.4 for patients with severe versus mild stenosis (p<0.001).
Writing in the American Heart Journal, the researchers conclude: “Contrary to previous belief, our finding suggests that greater stenosis severity is associated with IRLs, which is consistent with our finding of greater atheroma burden generally in infarct-related arteries.”
They note: “Our study also raises the possibility of a role of compression CAM in plaque vulnerability. These angiographic characteristics may ultimately aid in the early detection of the vulnerable plaque.”
MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2010
By Joel Levy