Abstract 18183: Association of Morphological Characteristics Of Culprit Atheromatic Plaque with Thrombus Burden Following Thrombolytic Therapy: An Optical Coherence Study
Background: In patients with ST-elevation myocardial infarction (STEMI), residual thrombus is often present in the culprit lesion despite thrombolytic administration. It is not known whether culprit lesion morphological characteristics are associated with residual thrombus after thrombolysis. We investigated in patients with STEMI the association between the morphological characteristics of culprit atheromatic lesions as assessed by optical coherence tomography (OCT) and the angiographic thrombus burden after thrombolysis.
Methods: We prospectively enrolled 55 consecutive patients with STEMI from 3 tertiary centers that were treated with thrombolysis and underwent coronary angiography within 24 hours from thrombolysis. Angiographic assessment of thrombus burden was performed and thrombus burden was categorized in 6 grades (G0-G5) using a previously described classification. Lesion assessment by OCT was then performed in all patients. Minimum cap thickness was measured at the thinnest part over a necrotic core and the incidence of thin cap fibroatheroma (plaque with necrotic core and cap thickness =<65 um) and plaque rupture were recorded.
Results: There were 27 patients with thrombus burden G0, 9 with G1, 6 with G2, 7 with G3, 1 with G4 and 5 with G5. In OCT examination, 50.9% (n=28) of the patients presented with a thin cap fibroatheroma and a rupture was identified in 49.1% (n=27) of the patients. Thrombus burden was increased in patients with thin cap fibroatheroma (median 1, interquartile range [IQR] 2) compared to patients without thin cap fibroatheroma (median 0, IQR 2, p<0.05). There was a trend for increased thrombus burden in patients with plaque rupture, that did not reach statistical significance (median 1, IQR 2 vs. median 0, IQR 2, p=0.13).
Conclusions: In patients with STEMI, thrombus burden after thrombolytic administration is associated with thin cap fibroatheroma. This study suggests that specific morphological features of the culprit lesion are associated with the extent of thrombus resolution after thrombolysis in patients with STEMI.
- © 2010 by American Heart Association, Inc.