Gd(ABE-DTTA)-enhanced cardiac MRI for the diagnosis of ischemic events in the heart.
OBJECTIVE
To demonstrate that contrast-enhanced MRI (ceMRI) with the aid of Gd(ABE-DTTA) is able to detect ischemic events in the heart in a canine ischemia/reperfusion (30/40 minutes) model.


METHODS
ECG-gated, T1-weighted MR image sets (four to five slices each) with three-minute time resolution were collected in transiently LAD-occluded dogs. Following the acquisition of control image sets, ischemia was started by occluding the LAD. Either Gd(ABE-DTTA) (N = 6) or Gd(DTPA) (N = 6) was injected, and imaging was continued for 30 minutes of ischemia and 40 minutes of reperfusion. The contrast agent (CA)-induced MRI signal intensity enhancement (SIE) and contrast were monitored. Microspheres measured myocardial perfusion (MP) to verify areas of ischemia and reperfusion.


RESULTS
SIEs of 86% +/- 3% and 97% +/- 3% in nonischemic, and 25% +/- 5% and 29% +/- 8% in ischemic regions were found within three minutes of onset of ischemia with Gd(ABE-DTTA) and Gd(DTPA), respectively. For the rest of the 30 minutes of ischemia, with Gd(ABE-DTTA) SIE of 60% +/- 3% and 25% +/- 5% persisted in the nonischemic and ischemic regions, respectively. With Gd(DTPA), however, SIE in the nonischemic areas decreased rapidly after the first three minutes of ischemia, while SIE in the ischemic areas increased, abolishing contrast. Thus, there was a persistent contrast with Gd(ABE-DTTA) and a short-lived contrast with Gd(DTPA) during ischemia. Furthermore, with Gd(ABE-DTTA) some contrast was still visible in the early reperfusion period.


CONCLUSIONS
Gd(ABE-DTTA) in an ischemia/reperfusion model induces a persistent MRI contrast between regions of normal and ischemic myocardium, and verifies reperfusion. Therefore, it can be used to detect myocardial ischemic events.
Simor
Tamás
T
Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Alabama 35294-0005, USA.
Gaszner
Balázs
B
Oshinski
John N
JN
Waldrop
Sandra M
SM
Pettigrew
Roderic I
RI
Horváth
Iván G
IG
Hild
Gábor
G
Elgavish
Gabriel A
GA
D000704:Analysis of Variance; D000818:Animals; D003287:Contrast Media; D004285:Dogs; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D017202:Myocardial Ischemia / Q000175:diagnosis*; D009942:Organometallic Compounds; D004369:Pentetic Acid; D012815:Signal Processing, Computer-Assisted
D003287:Contrast Media; D009942:Organometallic Compounds; C120791:gadolinium N-(2-butyryloxyethyl)-N'-(2-ethyloxyethyl)-N,N'-bis(N'',N''-bis(carboxymethyl)acetamido)-1,2-ethanediamine; D004369:Pentetic Acid