ISSN:
1432-1084
Keywords:
Metalloporphyrins
;
Myocardial infaction
;
Necrosis
;
MRI
;
Contrast media
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract In previous experiments in tumors we demonstrated that metalloporphyrins are particularly avid for nonviable tumor components. This study was performed to find out wether these agents can be used as MRI contrast agents for the visualization of acute myocardial infarction (MI). A total of 44 rats, 6 normal controls and 38 with occlusive MI (2–24 h old), were used. Gadolinium mesopophyrin (Gd-MP) or manganese totraphenylporphyrin (Mn-TPP) was intravenously injected at doses of 0.1, 0.05, and 0.01 mmol.kg. Three to 24 h after injection, axial and coronal T1-weighted (TR/TE 300/15 ms) spinecho MR images were obtained before and after killing the animals and correlated with triphenyl tetrazolium chloride (TTC) histocemical preparations. The Gd-MP content in infarcted and noninfarcted myocardium was measured using inductively coled plasma atomic emission spectroscopy (ICP-AES) MRI without contrast media could not discern the MI. However, 3–24 h after injection of either Gd-MP or Mn-TPP, the infarcted area was positively stained on MR images. This area matched well witht he negatively TTC-stained area on the heart slices (r = 0.97). The contrast ratios between the infarcted nectrotic myocardium and the noninfarcted regions varied from 150 to 300% depending on the tye of agensts and doses used. Neither false-positive nor false-negative findings were encountered. The metallaporphyrin concentration was more than 10 times higher in the infarcted than in the noninfarcted heart. Metalloporphyrins appear to be promising MRI contrast agents for detection and quantification of necrosis in MI. These preclinical results may open new perspectives in cardiac imaging.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00619942
