We evaluated whether delayed contrast-enhanced magnetic resonance imaging (DCE-MRI)
using an extracellular contrast agent could predict improvement of dysfunctional but
viable myocardium after acute reperfused myocardial infarction (MI).
The transmural extent of hyperenhancement at DCE-MRI has been related to improvement
of function in reperfused MI. However, evidence is still limited, and earlier reports
have produced conflicting results regarding the significance of contrast patterns
after infarction.
Thirty patients (mean age 59 +/- 11 years, 27 males) underwent cine MRI and DCE-MRI
7 +/- 3 days after a first reperfused acute MI and follow-up cine MRI at 13 +/- 3
weeks. Segmental wall thickening and segmental extent of hyperenhancement were scored
in 1,689 segments.
Of 500 dysfunctional segments, 273 (55%) improved at follow-up. There was no difference
in likelihood of improvement or complete functional recovery between segments with
0% and 1% to 25% hyperenhancement. The likelihood of improvement of segments without
hyperenhancement was 2.9, 14.3, and 20 times higher than that of segments with 26%
to 50%, 51% to 75%, and >75% hyperenhancement, respectively (p < 0.001). The likelihood
of complete functional recovery of segments without hyperenhancement was 3.8, 11.1,
and 50 times higher than that of segments with 26% to 50%, 51% to 75%, and >75% hyperenhancement,
respectively (p < 0.001).
In patients with recent reperfused MI, functional improvement of stunned myocardium
is predicted by DCE-MRI.