Abstract:
:To determine if magnetic resonance imaging (MRI) can be used to detect tissue viability in segments with persistent 201T1 defects early following acute myocardial infarction, 24 patients underwent MRI and adenosine 201T1 single photon emission computed tomography (SPECT) imaging at approximately 6 days. Infarction was demonstrated on MRI using a velocity-compensated, T2-weighted spin-echo pulse sequence. Wall thickening was assessed using a gradient-echo pulse sequence obtained in the same anatomic position. Viable myocardium was defined by MRI as a segment with increased signal intensity and preserved wall thickening. A fixed defect on the 201T1 SPECT images was defined as the absence of any redistribution 4 hours after the 201T1 infusion. Of 11 patients with redistribution on the 201T1 images in the infarction region, 10 (91%) had preserved wall thickening by MRI. Of 13 patients with fixed defects on the 201T1 images in the infarction region, 6 (46%) had preserved wall thickening by MRI. Of 7 patients with absent thickening, all had one or more segments with absent perfusion on redistribution imaging. Wall thickening tended to occur in patients who received thrombolytic therapy or who underwent revascularization procedures prior to imaging. The results of the present study suggest that spin-echo MRI with motion compensation can be used to identify viable myocardium in patients with fixed defects on 201T1 SPECT following acute myocardial infarction.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Johnston DL,Gupta VK,Wendt RE,Mahmarian JJ,Verani MSdoi
10.1016/0730-725x(93)90214-xsubject
Has Abstractpub_date
1993-01-01 00:00:00pages
949-56issue
7eissn
0730-725Xissn
1873-5894pii
0730-725X(93)90214-Xjournal_volume
11pub_type
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