Myocardial perfusion imaging agents

Fig. 4. Lipophilic-cationic( +1) myocardial perfusion imaging agents A) 99mTc-tetrofosmin R = -CH2CH,0CH,CH3 B), 9"Tc = sestamibi R=C=NCH,C (OCHJ (CH,), Q 99mTc-furifosmin R = -CH2CH2OCH2CH3...

Deutsch E, Libson K, Jurisson S, Lindoy LF (1983) Technetium chemistry and technetium radiopharmaceuticals In Lippard SJ (ed) Progress in inorganic chemistry. Wiley, New York, pp 75-139 Deutsch E, Vanderheyden J-L, Gerundini P, Libson K et al (1987) Development of non reducible technetium-99m(III) cations as myocardial perfusion imaging agents initial experience in humans. J Nucl Med 28 1870-1880... 

Jain D, Wackers FJT, Mattera J, McMahon M, Sinusas AJ, Zaret BL (1993) Biokinetics of techne-tium-99m-tetrofosmin myocardial perfusion imaging agent implications for a one-day imaging protocol. J Nucl Med 34 1254-1259... 

ITiis cationic myocardial perfusion imaging agent was developed more recently. Tetrofos-min is the ether functionalized diphosphinc ligand l,2-bis bis(2-ethoxyethyl)phosphino ... 

Some promising myocardial perfusion imaging agents were developed in the last decade. Reactions of "TcO with both 2-phcnylcnc-bis(dimcthylarsine) (diars) and various thiols (RSH) yielded a scries of monocationic " Tc "(diars)7(SR)2] complexes. The analogous complex cations of long-lived sTc were identified by FAB mass spectroscopy. All the [ " Tc "(diars)7(SR)2l cations, which are in vivo non-reducible. 

A seven-coordinate technetium(UI) complex has also been commercially developed as a myocardial perfusion imaging agent [3]. While this complex is neutral in the solid state, it readily loses a chloride ligand and may in fact exist in vivo as a mixture of neutral and cationic forms [3,16]. 

Mechanism of Action A cardiac agent that slows impulse formation in the SA node and conduction time through the AV node. Adenosine also acts as a diagnostic aid in myocardial perfusion imaging or stress echocardiography. Therapeutic Effect Depresses left ventricular function and restores normal sinus rhythm. 

Heart Agents. Routine myocardial perfusion imaging in nuclear medicine started with ° T1 thallous chloride. While ° T1+ is efficiently perfused into the myocardium, the long half-life and imaging characteristic s are not optimal for nuclear medicine imaging and cationic Tc-based perfusion agents were desired. 

MDCT techniques are currently under investigation with respect to myocardial perfusion imaging and show close correlation to microsphere data (George et al. 2006, 2007). With respect to real CT perfusion imaging with dynamic contrast agent tracing, the following facts may currently restrict the use to scientific evaluation only ... 

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