Abstract 5450: Detection of Intracoronary Thrombus by Magnetic Resonance Imaging in Patients With Acute Coronary Syndrome
Background: Persistent intracoronary thrombus following plaque rupture is associated with an increased risk of subsequent myocardial infarction and mortality. Presently, coronary thrombus can only be visualized invasively by X-Ray Angiography (XRA), intravascular ultrasound, or angioscopy. Purpose: The aim of this study was to investigate the use of non-contrast enhanced magnetic resonance imaging for direct thrombus visualization (MRDTI) in patients with a recent ACS (troponin T >1.0).
Method and Results: 14 patients (13 male) underwent MRDTI within 24 –72h of presenting with ACS prior to invasive X-ray angiography (XRA). MRDTI (fig. a⇓) was performed using a navigator-gated free breathing and cardiac-triggered T1-weighted 3D inversion-recovery black-blood gradient-echo sequence without contrast administration. 7 patients were found to have intracoronary thrombus on XRA ±/− thrombus extraction (2xLAD, 1xLCX, 3xRCA and 1PDA branch of RCA) (fig c⇓.) and 7 had no visible thrombus. MRDTI (fused with magnetic resonance angiography, fig. b⇓) correctly identified thrombus in 6 of 7 patients (PDA thrombus not detected) and correctly classified the control group of 7 patients without thrombus formation. Contrast to noise ratio of thrombus as compared to the vessel lumen of non-affected segments was 6-fold increased (67.5±12.2 vs. 10.2±6.6, p <0.01).
Conclusion: MRDTI allows selective visualization of coronary thrombus in patients after myocardial infarction. This technique may be useful for direct coronary thrombus detection in patients with ACS or unstable angina.