Erosion main source of healing thrombi in sudden death patients
MedWire News: A study of sudden death patients with acute myocardial infarction (MI) suggests that plaque erosions rather than ruptures are the main cause of the healing coronary thrombi, associated with poor outcome in this population.
Understanding that the lesion damage and thrombi might exist up to several weeks before a sudden death, Renu Virmani (Academic Medical Center, Amsterdam, The Netherlands) and co-authors examined differences in healing between thrombi associated with ruptured and eroded plaques.
The researchers examined coronary lesions with thrombi from sudden death patients, including 65 with ruptures and 50 with erosions. Thrombus healing was classified as being in the early (<1 day) or in the latestages of healing, lysis (1–3 days), infiltrating (4–7 days), or healing (>7 days).
Overall, 69% of thrombi from culprit plaques were classified as late stage, the team reports in the Journal of the American College of Cardiology.
Early thrombi (46% vs 12%) and lytic thrombi were significantly more common from plaque ruptures than erosions, whereas the majority of thrombi in erosions were infiltrating or healing (46% vs 9%).
Patients with ruptures were older on average than those with erosions (52 vs 43 years). Thrombi in womenaccounted for a higher proportion of erosions than ruptures (26% vs 11%), and women were more likely to have late-stage thrombi with erosions than ruptures (88% vs 54%).
Analysis showed that erosions had significantly smaller internal elastic lamina area and percent stenosis than ruptures, but significantly greater plaque burden. Erosions had less macrophage infiltration than ruptures but there was no association between thrombus organization and erosions.
There was no correlation between healing stage and thrombus length or whether the thrombus was occlusive or nonocclusive.
“Considering that ST- elevation MI patients with healing thrombi of more than1 day have poorer prognosis, the present findings that erosions are the main cause of healing thrombi – which occur predominantly in women and younger men – together with the increased risk for distal intramyocardial embolization ,would further indicate that women and younger men might require different strategies of treatment,” the team concludes.
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 Lynda Williams