Acute effects of commonly used drugs in the cardiac care unit on the myocardial extraction kinetics of 99mTc-Sestamibi.
This study was undertaken to assess the potential effects of drugs commonly used in the cardiac care unit (CCU) as well as other pharmacological interventions on the biodistribution of 99mTc-hexakis-2-methoxy-2-methylpropyl isonitrile, 99mTc-Sestamibi. 99mTc-Sestamibi was administered i.v. into pentobarbital anesthetized guinea pigs pretreated with either saline (control), verapamil (0.1 mg/kg), digoxin (0.2 mg/kg), propranalol (1 mg/kg), dipyridamole (1.2 mg/kg). The results showed that none of the above interventions decreased the myocardial biodistribution of 99mTc-Sestamibi. On the other hand, digoxin, propranalol and dipyridamole produced an increase in the myocardial uptake of 99mTc-Sestamibi. Furthermore, pretreatment with the ligand which is being used in the formulation of the kit, copper tetrakis-2-methoxy-2-methylpropyl isonitrile (Cu[MIBI]4) at doses ranging from 0.1 to 2.5 mg/kg did not interfere with the biodistribution of 99mTc-Sestamibi in guinea pig. An additional study was carried out in swine to determine the effect of dipyridamole (0.4 mg/kg) on the regional myocardial distribution of 99mTc-Sestamibi in relation to regional myocardial blood flow (microspheres-determined). This study clearly documented a direct relationship between regional myocardial blood flow and the myocardial distribution of 99mTc-Sestamibi (i.e. for each increase or decrease in blood flow there is a parallel increase or decrease in myocardial 99mTc-Sestamibi distribution). These studies indicated that any of the above drugs could be used in the CCU while imaging with 99mTc-Sestamibi.
Mousa
S A
SA
E.I. Du Pont de Nemours and Co., Inc., Medical Products Department, N. Billerica, MA.
Carroll
T R
TR
Morgan
R A
RA
D000818:Animals; D003325:Coronary Care Units; D003327:Coronary Disease / Q000175:diagnosis; D004077:Digoxin / Q000494:pharmacology; D004176:Dipyridamole / Q000494:pharmacology; D004347:Drug Interactions; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics*; D013552:Swine; D013556:Swine, Miniature; D017256:Technetium Tc 99m Sestamibi; D014700:Verapamil / Q000494:pharmacology
D015609:Organotechnetium Compounds; D004176:Dipyridamole; D004077:Digoxin; D017256:Technetium Tc 99m Sestamibi; D014700:Verapamil