Evaluation of acute myocardial infarction with late enhancement pattern on MRI compared with 201Tl and 99mTc-hydroxymethylenediphosphonate (HMDP) dual single photon emission computed tomography (SPECT) images.
The purpose of this study is to evaluate reperfused acute myocardial infarction with late enhancement (LE) pattern on contrast-enhanced magnetic resonance imaging compared with myocardial single photon emission computed tomography (SPECT) images.


METHODS
Magnetic resonance and 201Tl and 99mTc-hydroxymethylenediphosphonate SPECT images were obtained from 40 patients within 6 days of reperfused myocardial infarction. We assessed the myocardial LE pattern using the true fast imaging with steady-state free precession sequence after the injection of Gd-DTPA. Patients were classified into 3 groups: group 1 included patients with localized endocardial enhancement; group 2, patients with transmural enhancement; and group 3, patients with LE and a residual defect.


RESULTS
There were 9 patients (23%) in group 1, 15 (38%) in group 2, and 15 (38%) in group 3. In 1 patient, LE was not detected (3%). The %201Tl uptake for the infarcted area was 60.7 +/- 7.2 (mean +/- SD) for group 1, 49.5 +/- 12.3 (P < 0.05 vs. group 1) for group 2, and 36.9 +/- 8.2 (P < 0.0001 vs. group 1, P = 0.005 vs. group 2) for group 3. An overlap pattern of 201Tl and 99mTc was observed in 9 of the group 1 patients (100%) and 9 of the group 2 patients (60%), but was not evident in group 3 (0%).


CONCLUSIONS
LE with residual defect is an important indicator of microvascular obstruction after reperfusion therapy.
Nagao
Michinobu
M
Department of Radiology, Prefectural Ehime Imabari Hospital, Japan. i-minagao@epnh.pref.ehime.jp
Higashino
Hiroshi
H
Matsuoka
Hiroshi
H
Kawakami
Hideo
H
Miyagawa
Masao
M
Mochizuki
Teruhito
T
Uemura
Masahiko
M
Tokunaga
Nobuko
N
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013669:Technetium Tc 99m Medronate / Q000031:analogs & derivatives*; D013793:Thallium; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000209:etiology
D019275:Radiopharmaceuticals; C027549:thallium chloride; C024226:technetium Tc 99m hydroxymethylene diphosphonate; D013793:Thallium; D013669:Technetium Tc 99m Medronate