Noninvasive In Vivo Coronary Artery Thrombus Imaging

Background The diagnosis and management of myocardial infarction are increasingly complex, and establishing the presence of intracoronary thrombosis has major implications for both the classification and treatment of myocardial infarction. Objectives The aim of this study was to investigate whether positron emission tomographic (PET) and computed tomographic (CT) imaging could noninvasively detect in vivo thrombus formation in human coronary arteries using a novel glycoprotein IIb/IIIa receptor antagonist–based radiotracer, 18 F-GP1. Methods In a single-center observational case-control study, patients with or without acute myocardial infarction underwent coronary 18 F-GP1 PET/CT angiography. Coronary artery 18 F-GP1 uptake was assessed visually and quantified using maximum target-to-background ratios. Results 18 F-GP1 PET/CT angiography was performed in 49 patients with and 50 patients without acute myocardial infarction (mean age: 61 ± 9 years, 75% men). Coronary 18 F-GP1 uptake was apparent in 39 of the 49 culprit lesions (80%) in patients with acute myocardial infarction. False negative results appeared to relate to time delays to scan performance and low thrombus burden in small-caliber distal arteries. On multivariable regression analysis, culprit vessel status was the only independent variable associated with higher 18 F-GP1 uptake. Extracoronary cardiac 18 F-GP1 findings included a high frequency of infarct-related intramyocardial uptake (35%) as well as left ventricular (8%) or left atrial (2%) thrombus. Conclusions Coronary 18 F-GP1 PET/CT angiography is the first noninvasive selective technique to identify in vivo coronary thrombosis in patients with acute myocardial infarction. This novel approach can further define the role and location of thrombosis within the heart and has the potential to inform the diagnosis, management, and treatment of patients with acute myocardial infarction. (In-Vivo Thrombus Imaging With 18 F-GP1, a Novel Platelet PET Radiotracer iThrombus; NCT03943966 )