Imaging of myocardial infarction: comparison of magnevist and gadophrin-3 in rabbits.

Abstract

OBJECTIVES:

This study was designed to determine the enhancement profile of a necrosis-specific contrast agent (gadophrin III) in comparison to a standard extracellular agent on T1-weighted magnetic resonance (MR) images in acute and chronic myocardial infarctions (MIs).

BACKGROUND:

Contrast-enhanced MR imaging demonstrated the ability to accurately quantify infarct size; however, some controversies persist about which contrast medium is best suited.

METHODS:

Fifteen rabbits underwent thoracotomy and permanent occlusion of a branch of the left coronary artery. Two animals died before imaging, eight were examined 48 h after occlusion and five animals were imaged six weeks following induction of infarction. All animals received 50 micromol/kg of gadophrin-3 24 h before the MR examination. Continuous short-axis views were collected using an inversion recovery turbo fast low angle shot sequence. Imaging was repeated 5 to 10 min following additional injection of 100 micromol/kg of Magnevist. The area of hyperenhancement demarcated following gadophrin-3 injection was compared with the region of hyperenhancement seen on gadophrin-3 plus Magnevist enhanced image using triphenyltetrazolium chloride (TTC) staining as the standard of reference.

RESULTS:

In acute MI the mean difference in size of hyperenhancement seen on the two different in vivo MR scans was -1.8 +/- 6.0 mm(2) (p > 0.05). Both measurements showed excellent agreement with TTC staining. Chronic MIs showed no enhancement with gadophrin-3, whereas application of Magnevist resulted in hyperenhancement. CONCLUSIONS; Standard extracellular contrast agents do not overestimate the size of acute MI. The combination of gadophrin-3 and Magnevist can distinguish acute and chronic myocardial injury because chronic MIs do not enhance with gadophrin-3.

• Authors: Jörg Barkhausen, Wolfgang Ebert, Jörg F Debatin, Hanns-Joachim Weinmann
• Journal: Journal of the American College of Cardiology (J Am Coll Cardiol) Vol. 39 Issue 8 Pg. 1392-8 (Apr 17 2002) ISSN: 0735-1097 [Print] United States
• PMID: 11955861 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Contrast Media
• Tetrazolium Salts
• triphenyltetrazolium
• Gadolinium
• Gadolinium DTPA

Topics

• Animals
• Contrast Media (pharmacology)
• Disease Models, Animal
• Female
• Gadolinium (pharmacology)
• Gadolinium DTPA (pharmacology)
• Image Enhancement
• Injections, Intravenous
• Magnetic Resonance Imaging
• Male
• Myocardial Infarction (diagnosis, pathology)
• Rabbits
• Staining and Labeling
• Tetrazolium Salts