Manganese enhanced magnetic resonance imaging of normal and ischemic canine heart.
The ability of MnCl2 to enhance canine myocardium and to delineate ischemic areas is demonstrated. A dose-response curve was measured using T1 weighted images in 11 dogs. MnCl2 (36, 113, 360, and 3600 micromol) was infused over a period of 3 min. Signal intensity increased linearly with MnCl2 dose. At 113 micromol ( approximately 10 micromol/kg) the steady-state increase in intensity averaged 212 +/- 34%. No significant physiologic effects due to the infused MnCl2 were detected except at the highest dose where there was a cardiac depressive effect. Ischemia was induced by occluding the left anterior descending coronary artery in 5 dogs. At an infused dose of 113 micromol, MnCl2 clearly demarcated the ischemic zone during coronary occlusion. Contrast enhancement in the ischemic zone was less than 30% compared with normal tissue (P < 0.03). In conclusion, the intracellular contrast agent MnCl2 enhances the canine heart and shows promise in detecting ischemia at doses that do not cause adverse cardiac effects.
Hu
Tom C-C
TC
Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892-1061, USA.
Christian
Timothy F
TF
Aletras
Anthony H
AH
Taylor
Joni L
JL
Koretsky
Alan P
AP
Arai
Andrew E
AE
D000818:Animals; D003287:Contrast Media; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006352:Heart Ventricles / Q000187:drug effects / Q000473:pathology; D007089:Image Enhancement / Q000379:methods*; D007261:Infusions, Intra-Arterial; D015636:Magnesium Chloride / Q000008:administration & dosage*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D017202:Myocardial Ischemia / Q000150:complications / Q000473:pathology*; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000473:pathology*
D003287:Contrast Media; D015636:Magnesium Chloride