Abstract 13736: Differential Sensitivity of Plaque Rupture and Plaque Erosion to Thrombolytic Therapy in Patients With ST-segment Elevation Myocardial Infarction: an Optical Coherence Tomography Study
Objectives: Recent studies reported the ability of optical coherence tomography (OCT) to diagnose plaque erosion in vivo. In this study, we aimed to evaluate the nature of coronary thrombus, and to compare the sensitivity of plaque rupture and plaque erosion to thrombolytic therapy in patients with ST-segment elevation myocardial infarction (STEMI) by OCT.
Methods and Results: Culprit lesions in 23 patients were imaged by OCT after thrombolysis. The type and distribution of residual thrombus in relation to underlying plaque characteristics were analyzed. Plaque rupture and erosion were found in 11 (47.8%) and 8 (34.8%) patients, respectively. Residual thrombus score was higher in rupture compared with erosion (14.2 ± 9.4 vs. 6.5 ± 4.5, p=0.049). The core of thrombus was rich in platelets. When patients were divided according to underlying plaque characteristics, in plaque rupture, white thrombus was present primarily at the culprit site (1.6% [proximal], 22.5% [culprit site], and 5.2% [distal], p<0.001) and red thrombus was evenly distributed throughout the lesion (17.3% vs. 25.5% vs. 31.9%, p=0.184) (Figure 1A). In erosion cases, only white thrombus was seen in all the patients except one who had minimal red thrombus in the proximal segment (Figure 1B).
Conclusions: In patients with STEMI treated by thrombolysis, residual thrombus burden was greater in plaque rupture compared to plaque erosion. In plaque rupture, the core of thrombus was platelet-rich and erythrocyte-rich thrombus was present throughout the culprit lesion. In plaque erosion, platelet-rich thrombus was present at the culprit site without much residual erythrocyte-rich thrombus. STEMI patients caused by plaque erosion appear to be more sensitive to thrombolysis.
- © 2013 by American Heart Association, Inc.