Early uptake of 99mTc-C2A in the acute phase of myocardial infarction as a prognostic indicator for follow-up cardiac dysfunction.
OBJECTIVE
The C2A domain of Synaptotagmin I is a molecular probe for the specific imaging of cell death. Here we test the hypothesis that the uptake of 99mTc-C2A in the acute phase of an infarction is associated with cardiac dysfunction in follow-ups.


METHODS
The left coronary artery was occluded in Sprague-Dawley rats for 0, 10, 20, and 30 min. 99mTc-C2A was injected intravenously at 2 h of reperfusion. Anterior planar images were acquired with one million counts on a gamma camera 3 h after injection. 99mTc-C2A uptake was calculated as the total counts in the left ventricle region minus blood pool signal. The in-vivo signal detected was correlated with wall motion score index at 1 and 3 weeks follow-ups measured by echocardiography.


RESULTS
99mTc-C2A uptake was higher with increased ischemic time (2244+/-852, 4054+/-1223, and 6178+/-1451 for 10, 20, and 30 min ischemia, analysis of variance P<0.001). A significant correlation was found between 99mTc-C2A uptake and wall motion score index at 1 week (R=0.800, P=0.0006) and 3 weeks (R=0.810, P=0.0008).


CONCLUSIONS
In this ischemia/reperfusion model, 99mTc-C2A uptake in the acute phase was associated with functional abnormality at 1 and 3 weeks. This demonstrates the potential diagnostic and prognostic value of 99mTc-C2A as a novel imaging agent.
Zhu
Xiaoguang
X
Department of Biophysics, Nuclear Medicine Division, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
Migrino
Raymond Q
RQ
Hellman
Robert S
RS
Brahmbhatt
Tejas
T
Zhao
Ming
M
D000818:Animals; D004452:Echocardiography / Q000379:methods; D008297:Male; D009038:Motion; D009203:Myocardial Infarction / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D015425:Myocardial Reperfusion; D015609:Organotechnetium Compounds / Q000737:chemistry / Q000493:pharmacokinetics*; D011379:Prognosis; D019275:Radiopharmaceuticals; D051381:Rats; D017207:Rats, Sprague-Dawley; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000493:pharmacokinetics*; D015427:Reperfusion Injury; D050857:Synaptotagmins / Q000737:chemistry* / Q000493:pharmacokinetics; D013667:Technetium / Q000493:pharmacokinetics*; D013997:Time Factors
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D011993:Recombinant Fusion Proteins; C526993:technetium 99m C2A-glutathione transferase; D050857:Synaptotagmins; D013667:Technetium