A Comparison Between 99mTc-Q3 and 201Tl on Clearance and Retention Properties at Varying Coronary Flow Rates in Isolated Rabbit Heart
10.3969/j.issn.1672-173X.2001.02.020
- VernacularTitle:99mTc-Q3与201Tl在不同流量冠脉灌注的离体兔心肌中的清除及存留特性研究
- Author:
Chengzhong FAN
1
;
Tianzhi TAN
;
Yunchun LI
;
Anren KUANG
;
Zhenglu LIANG
;
Yue CHEN
Author Information
1. the First Affiliated Hospital WCUMS
- From:
Journal of Sichuan University (Medical Sciences)
2001;32(2):225-228,231
- CountryChina
- Language:Chinese
-
Abstract:
Objective This study was intended to investigate and compare technetium-99m-N,N′-ethylenebis(acetylacetoneiminato)bis〔tris (3-methoxy-1-propyl) phosphine〕 (99mTc-Q3) versus 201Tl on clearance and retention properties at varying coronary flow rates in isolated rabbit heart. Methods 20 New Zealand White rabbits were anaesthetized and excised through a median sternotomy. The hearts were isolated and arrested in ice-cold saline. The external perfusion models with isolated rabbit hearts were installed and were perfused at flow rates ranging from 0.52 to 3.75 ml/(g wet wt*min) in the absence of tracer recirculation. Furthermore,99mTc-Q3 experimental relations between uptake, clearance and retention were explored in comparison with 201Tl.Results 201Tl net uptake was higher and also more affected by flow rates (P< 0.05 ) as compared with 99mTc-Q3 net uptake.201Tl clearance was faster than 99mTc-Q3 clearance within 4 to 25 minutes after radiopharmaceuticals injection in high flow rates group, and 201Tl clearance was faster than 99mTc-Q3 clearance within 40 minutes after radiopharmaceuticals injection in low flow rates group.201Tl earlier rapid clearance observed in the high flow rates group did not appear in the low flow rates group, but 99mTc-Q3 did not display early rapid clearance either in the high flow rates group or in the low flow rates group. Conclusion Owing to faster clearance, the superiority of 201Tl over 99mTc-Q3 as a myocardial perfusion imaging agent would be lost entirely within 10 minutes after injection of agent, therefore 99mTc-Q3 is still a good myocardial perfusion imaging agent, and further study is worth doing.
