Diagnostic Performance of T1 and T2 Mapping to Detect Intramyocardial Hemorrhage in Reperfused ST-segment Elevation Myocardial Infarction Patients

Purpose: To investigate the performance of T-1 and T-2 mapping to detect intramyocardial hemorrhage (IMH) in ST-segment elevation myocardial infarction (STEMI) patients treated by primary percutaneous coronary intervention (PPCI). Materials and Methods: Fifty STEMI patients were prospectively recruited between August 2013 and July 2014 following informed consent. Forty-eight patients completed a 1.5T cardiac magnetic resonance imaging (MRI) with native T-1, T-2, and T-2(*) maps at 4 +/- 2 days. Receiver operating characteristic (ROC) analyses were performed to assess the performance of T-1 and T-2 to detect IMH. Results: The mean age was 59 +/- 13 years old and 88% (24/48) were male. In all, 39 patients had interpretable T-2(*) maps and 26/39 (67%) of the patients had IMH (T-2(*) < 20 msec on T-2(*) maps). Both T-1 and T-2 values of the hypointense core within the area-at-risk (AAR) performed equally well to detect IMH (T-1 maps AUC 0.86 [95% confidence interval [CI] 0.72-0.99] versus T-2 maps AUC 0.86 [95% CI 0.74-0.99]; P-0.94). Using the binary assessment of presence or absence of a hypointense core on the maps, the diagnostic performance of T-1 and T-2 remained equally good (T-1 AUC 0.87 [95% CI 0.73-1.00] versus T-2 AUC 0.85 [95% CI 0.71-0.99]; P=0.90) with good sensitivity and specificity (T-1: 88% and 85% and T2: 85% and 85%, respectively). Conclusion: The presence of a hypointense core on the T-1 and T-2 maps can detect IMH equally well and with good sensitivity and specificity in reperfused STEMI patients and could be used as an alternative when T-2(*) images are not acquired or are not interpretable.