Identification of coronary thrombus with a IIb/IIIa platelet inhibitor radiopharmaceutical, technetium-99m DMP-444: A canine model.
BACKGROUND
A diagnostic test that could distinguish between stable and unstable coronary atherosclerotic plaques would be useful. We tested the ability of a new glycoprotein IIb/IIIa platelet inhibitor DMP-444, labeled with technetium (Tc)-99 m, to identify platelet-rich thrombus by nuclear imaging in a canine model.


RESULTS
Combinations of a flow-limiting stenosis and 0 to 15 minutes of endothelial electrical stimulation at a site in the left anterior descending coronary artery were used to induce varying amounts of thrombus formation. In 10 animals with markedly positive nuclear images after the injection of Tc-99m DMP-444, the presence of platelet-rich thrombus was confirmed postmortem by gross appearance, high nuclear counts, and abundant platelets on electron microscopy. The 10 animals with negative images had lower counts, smaller thrombus weights (P<0.05 for each), and fewer platelets by electron microscopy.


CONCLUSIONS
Activated platelets participating in acute thrombus formation can be accurately detected by nuclear imaging using Tc-99 m DMP-444.
Mitchel
J
J
Nuclear Cardiology and Cardiac Catheterization Laboratories, Division of Cardiology, Hartford Hospital, Hartford, CT 06102-5037, USA. Jmitche@harthosp.org
Waters
D
D
Lai
T
T
White
M
M
Alberghini
T
T
Salloum
A
A
Knibbs
D
D
Li
D
D
Heller
G V
GV
D000818:Animals; D001792:Blood Platelets / Q000473:pathology; D003328:Coronary Thrombosis / Q000097:blood / Q000175:diagnosis* / Q000473:pathology; D004285:Dogs; D005240:Feasibility Studies; D008854:Microscopy, Electron; D015609:Organotechnetium Compounds; D015539:Platelet Activation; D010976:Platelet Count; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors*; D019275:Radiopharmaceuticals; D013438:Sulfhydryl Compounds
D015609:Organotechnetium Compounds; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D019275:Radiopharmaceuticals; D013438:Sulfhydryl Compounds; C038842:technetium Tc 99m 2,3-dimercaptopropionic acid