Detection of myocardial viability in acute infarction using contrast-enhanced (1)H magnetic resonance imaging.
BACKGROUND
Reperfusion strategies salvage myocardium at risk in acute myocardial infarction (MI). This clinical study was performed to determine whether areas without evidence of delayed MRI contrast enhancement in MI correspond to viability by means of percent systolic wall thickening (%SWT) and enddiastolic wall thickness (EDWT) in chronic infarction.


METHODS
Twenty MRI studies were performed in ten patients within 6 days of MI and 3 months post-MI. On a segmental basis the percentage of viable myocardium as defined by contrast-enhanced MRI (no delayed MRI contrast enhancement) in acute MI was measured and was compared with %SWT and EDWT in chronic MI.


RESULTS
Of the 1718 segments in acute infarction in which the percentage of viable myocardium was measured 1333 were found to be completely viable by means of contrast-enhanced MRI (no delayed MRI contrast enhancement). All of these segments revealed %SWT on day 90 post-MI, and 97% of segments were viable by means of an EDWT of more than 5.5 mm. In 85 segments the proportion of viable myocardium was 50-99% (mean 56+/-8%), with 92% segments found to be viable by means of %SWT and 92% by EDWT, and of 156 segments with viable myocardium between 1-49% (36+/-8%) 79% were found to be viable by means of %SWT and 82% by EDWT. Corresponding proportions of 144 segments with transmural delayed MRI contrast enhancement in acute MI were 45% and 17%.


CONCLUSIONS
In acute reperfused MI viable myocardium as delineated by contrast-enhanced MRI is correlated with clinical parameters of viability. Delayed MRI contrast enhancement resolves nontransmural MI and may become a valuable clinical tool when planning revascularization procedures.
Hillenbrand
H B
HB
Cardiology Division, Department of Medicine, Julius-Maximilians Universität, Luitpold Krankenhaus, Josef-Schneider Strasse 2, 97080 Würzurg, Germany.
Sandstede
J
J
Lipke
C
C
Köstler
H
H
Pabst
T
T
Werner
E
E
Ertl
G
G
Hahn
D
D
Bauer
W R
WR
D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000175:diagnosis*; D017682:Myocardial Stunning / Q000175:diagnosis / Q000209:etiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014022:Tissue Survival; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000209:etiology*
D003287:Contrast Media