Performance of contrast enhanced SSFP and T2-weighted imaging for determining myocardium at risk in a multi-vendor, multi-center setting- data from the MITOCARE and CHILL-MI trials

Quantification of myocardium at risk in ST- elevation myocardial infarction: a comparison of contrast-enhanced steady-state free precession cine cardiovascular magnetic resonance with coronary angiographic jeopardy scores

BACKGROUND

Clinical outcome following acute myocardial infarction is predicted by final infarct size evaluated in relation to left ventricular myocardium at risk (MaR). Contrast-enhanced steady-state free precession (CE-SSFP) cardiovascular magnetic resonance imaging (CMR) is not widely used for assessing MaR. Evidence of its utility compared to traditional assessment methods and as a surrogate for clinical outcome is needed.

METHODS

Retrospective analysis within a study evaluating post-conditioning during ST elevation myocardial infarction (STEMI) treated with coronary intervention (n = 78). CE-SSFP post-infarction was compared with angiographic jeopardy methods. Differences and variability between CMR and angiographic methods using Bland-Altman analyses were evaluated. Clinical outcomes were compared to MaR and extent of infarction.

RESULTS

MaR showed correlation between CE-SSFP, and both BARI and APPROACH scores of 0.83 (p < 0.0001) and 0.84 (p < 0.0001) respectively. Bias between CE-SSFP and BARI was 1.1% (agreement limits -11.4 to +9.1). Bias between CE-SSFP and APPROACH was 1.2% (agreement limits -13 to +10.5). Inter-observer variability for the BARI score was 0.56 ± 2.9; 0.42 ± 2.1 for the APPROACH score; -1.4 ± 3.1% for CE-SSFP. Intra-observer variability was 0.15 ± 1.85 for the BARI score; for the APPROACH score 0.19 ± 1.6; and for CE-SSFP -0.58 ± 2.9%.

CONCLUSION

Quantification of MaR with CE-SSFP imaging following STEMI shows high correlation and low bias compared with angiographic scoring and supports its use as a reliable and practical method to determine myocardial salvage in this patient population.

TRIAL REGISTRATION

Clinical trial registration information for the parent clinical trial: Karolinska Clinical Trial Registration (2008) Unique identifier: CT20080014. Registered 04th January 2008.