Paramagnetic pyrophosphate. Preliminary studies on magnetic resonance contrast enhancement of acute myocardial infarction

Journal Article · Thu Feb 01 04:00:00 EST 1990 · Investigative Radiology; (USA)

DOI:https://doi.org/10.1097/00004424-199002000-00011· OSTI ID:6969217

Maurer, A H; Knight, L C; Siegel, J A; Elfenbein, I B; Adler, L P ^[1]

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1. Temple Univ. Hospital, Philadelphia, PA (USA)

Ferric pyrophosphate (Fe-PyP) was investigated in an animal model of acute myocardial infarction for its potential to provide contrast enhancement of the peri-infarct zone using magnetic resonance (MR) imaging. Radiotracer studies compared the biodistribution of soluble 59Fe-PyP with 99mTc-PyP in excised tissue samples. Preferential localization of 59Fe-PyP in the peri-infarct zone was found to be similar to 99mTc-PyP. The ratio (percent dose/gram of tissue) at the edge of the infarct to normal tissue was 1.30 +/- 0.16 and 1.44 +/- 0.33 for 99mTc-PyP and 59Fe-PyP, respectively. In initial studies with high doses of the contrast agent, gated T1-weighted MR images of animals with 48-hour-old infarcts were obtained at 15-minute intervals after injection of Fe-PyP at a dose of 350 mg/kg. Contrast enhancement of the infarct zone was observed in all studies and was maximal 15-30 minutes after injection. Signal intensity ratios (infarct/normal) increased from a baseline 1.31 +/- 0.22 to a peak 1.90 +/- 0.57. Studies were then performed with smaller amounts of Fe-PyP. Images obtained with 50 mg/kg Fe-PyP showed contrast enhancement beginning at 60 minutes. Toxicology studies showed primarily respiratory effects, which became significant at doses of 190 mg/kg. These preliminary studies suggest that Fe-PyP potentially could serve as an MR contrast agent to localize and size acute myocardial infarcts; however, its clinical use may be limited by potential toxicity and dose limitations.

• OSTI ID: 6969217
• Journal Information: Investigative Radiology; (USA), Journal Name: Investigative Radiology; (USA) Journal Issue: 2 Vol. 25:2; ISSN INVRA; ISSN 0020-9996
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
COMPARATIVE EVALUATIONS
CONTRAST MEDIA
DAYS LIVING RADIOISOTOPES
DIAGNOSIS
DIAGNOSTIC TECHNIQUES
DISEASES
DISTRIBUTION
DOMESTIC ANIMALS
EVEN-ODD NUCLEI
HEART
HOURS LIVING RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
IRON 59
IRON ISOTOPES
ISOMERIC NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAGNETIC RESONANCE
MAMMALS
MUSCLES
MYOCARDIAL INFARCTION
MYOCARDIUM
NMR IMAGING
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ODD-EVEN NUCLEI
ORGANS
OXYGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
PYROPHOSPHATES
RADIOISOTOPES
RESONANCE
SWINE
TECHNETIUM 99
TECHNETIUM ISOTOPES
TISSUE DISTRIBUTION
TOXICITY
VERTEBRATES
YEARS LIVING RADIOISOTOPES