Contrast enhanced and functional magnetic resonance imaging for the detection of viable myocardium after infarction.
OBJECTIVE
Viable myocardium after acute myocardial infarction may be characterized by magnetic resonance imaging (MRI) either by demonstration of recovery of wall motion under dobutamine stress or by perfusion patterns after contrast medium administration. This study examines the relation between the two techniques.


METHODS
Gradient-echo MRI at rest and under low-dose dobutamine stress was performed in 28 patients within the first 2 weeks after acute myocardial infarction. In addition, spin-echo MRI was performed after gadolinium-DOTA administration. Wall motion at rest and under stress was scored to assess the contractile reserve of the infarct regions. Infarct enhancement patterns were classified as subendocardial, transmural, or as a doughnut pattern.


RESULTS
Subendocardial or absent infarct enhancement was related to functional recovery under stress in 31 of 37 infarct segments. Transmural infarct enhancement was correlated with the absence of functional recovery in 10 of 17 infarct segments (p < 0.002), indicating nonviability. The doughnut pattern was exclusively associated with the absence of viability (five of five).


CONCLUSIONS
Contrast enhancement patterns are related to residual myocardial viability.
Dendale
P
P
Department of Cardiology, Free University of Brussels (VUB), Belgium.
Franken
P R
PR
Block
P
P
Pratikakis
Y
Y
De Roos
A
A
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D003287:Contrast Media; D003326:Coronary Circulation / Q000502:physiology*; D004280:Dobutamine; D005080:Exercise Test; D005260:Female; D006571:Heterocyclic Compounds; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D009942:Organometallic Compounds; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D015912:Thrombolytic Therapy; D014022:Tissue Survival / Q000502:physiology
D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; D004280:Dobutamine; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate