Acute infarct selective MRI contrast agent.

Abstract

To determine the infarct affinity of a low molecular weight contrast agent, Gd(ABE-DTTA), during the subacute phase of myocardial infarct (MI). Dogs (n = 7) were examined, using a closed-chest, reperfused MI model. MI was generated by occluding for 180 min the left anterior descending (LAD) coronary artery with an angioplasty balloon. DE-MRI images with Gd(ABE-DTTA) were obtained on days 4, 14, and 28 after MI. Control DE-MRI by Gd(DTPA) was carried out on day 27. T2-TSE images were acquired on day 3, 13 and 27. Triphenyltetrazolium chloride (TTC) histomorphometry validated postmortem the existence of infarct. Gd(ABE-DTTA) highlighted the infarct on day 4, but not at all on day 14 or on day 28, following MI. On day 4, the mean ± SD signal intensity (SI) of infarcted myocardium in the presence of Gd(ABE-DTTA) significantly differed from that of healthy myocardium (45 ± 6.0 vs. 10 ± 5.0, P < 0.05), but it did not on day 14 (11 ± 9.4 vs. 10 ± 5.7, P = NS), nor on day 28 (7 ± 1.5 vs. 7 ± 2.4, P = NS). The mean ± SD signal intensity enhancement (SIE) induced by Gd(ABE-DTTA) was 386 ± 165% on day 4, significantly different from mean SIE on day 14 (9 ± 20%), and from mean SIE on day 28 (12 ± 18%), following MI (P < 0.05). The last two mean values did not differ significantly (P = NS) from each other. As control, Gd(DTPA) was used and it did highlight the infarct on day 27, inducing a mean SIE value of 312 ± 40%. The mean SIE on day 3, 13, or 27 did not vary significantly (P = NS) on the T2-TSE images (114 ± 41%, 123 ± 41%, and 150 ± 79%, respectively). Post mortem, the existence of infarcts was confirmed by TTC staining. The infarct affinity of Gd(ABE-DTTA) vanishes in the subacute phase of scar healing, allowing its use for infarct age differentiation early on, immediately following the acute phase.

• Authors: Robert Kirschner, Akos Varga-Szemes, Tamas Simor, Pal Suranyi, Pal Kiss, Balazs Ruzsics, Brigitta C Brott, Ada Elgavish, Gabriel A Elgavish
• Journal: The international journal of cardiovascular imaging (Int J Cardiovasc Imaging) Vol. 28 Issue 2 Pg. 285-93 (Feb 2012) ISSN: 1875-8312 [Electronic] United States
• PMID: 21336553 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Contrast Media
• Organometallic Compounds
• gadolinium N-(2-butyryloxyethyl)-N'-(2-ethyloxyethyl)-N,N'-bis(N'',N''-bis(carboxymethyl)acetamido)-1,2-ethanediamine
• Pentetic Acid
• Gadolinium DTPA

Topics

• Animals
• Contrast Media
• Diagnosis, Differential
• Disease Models, Animal
• Dogs
• Gadolinium DTPA
• Magnetic Resonance Imaging
• Myocardial Infarction (diagnosis, pathology)
• Myocardium (pathology)
• Organometallic Compounds
• Pentetic Acid
• Predictive Value of Tests
• Sensitivity and Specificity
• Time Factors