Detection of acute atrial thrombus in a porcine model with atrial fibrillation with tc 99m-apcitide.

RATIONALE AND

OBJECTIVES

Technetium-99m apcitide (AcuTect) is a peptide with high affinity and specificity for glycoprotein IIb/IIIa receptors on platelets and is currently approved for the diagnosis of deep venous thrombosis. This study evaluates the use of Tc-99m apcitide for detecting intracardiac thrombus in an animal model with atrial fibrillation.

METHODS

Thrombogenic material (0.23+/- 0.03 g) was implanted within the left atrium of 5 swine with induced atrial fibrillation. Scintigraphy was performed with a small field of view gamma camera (minimum of 400000 counts) 1 hour after implantation at 10, 60, and 120 minutes after the injection of the Tc-99m apcitide. Animals were then euthanized and a postmortem examination performed to confirm thrombus formation.

RESULTS

: In all animals, thrombi and microthrombi were confirmed within the left atrial appendage. The average wet weight of the thrombus was 1.4 +/- 0.2 g. Tc-99m apcitide detected left atrial thrombus in all animals.

CONCLUSIONS

This study suggests that AcuTect may prove useful for detecting intracardiac thrombus in future clinical studies in man.