Displacement Encoding With Stimulated Echoes Enables The Identification Of Infarct Transmurality Early Postmyocardial Infarction

Background Segmental extent of infarction assessed by late gadolinium enhancement (LGE) imaging early post-ST-segment elevation myocardial infarction (STEMI) has utility in predicting left ventricular functional recovery. Hypothesis We hypothesized that segmental circumferential strain with displacement encoding with stimulated echoes (DENSE) would be a stronger predictor of infarct transmurality than feature-tracking strain, and noninferior to extracellular volume fraction (ECV). Study Type Prospective. Population Fifty participants (mean +/- SD, 59 +/- 9 years, 40 [80%] male) underwent cardiac MRI on day 1 post-STEMI. Field-Strength/Sequences 1.5T/cine,DENSE,T(1)mapping,ECV,LGE. Assessment Two observers assessed segmental percentage LGE extent, presence of microvascular obstruction (MVO), circumferential and radial strain with DENSE and feature-tracking, T(1)relaxation times, and ECV. Statistical Tests Normality was tested using the Shapiro-Wilk test. Skewed distributions were analyzed utilizing Mann-Whitney or Kruskal-Wallis tests and normal distributed data using independentt-tests. Diagnostic cutoff values were identified using the Youden index. The difference in area under the curve was compared using the z-statistic. Results Segmental circumferential strain with DENSE was associated with the extent of infarction >= 50% (AUC [95% CI], cutoff value = 0.9 [0.8, 0.9], -10%) similar to ECV (AUC = 0.8 [0.8, 0.9], 37%) (P= 0.117) and superior to feature-tracking circumferential strain (AUC = 0.7[0.7, 0.8], -19%) (P < 0.05). For the detection of segmental infarction >= 75%, circumferential strain with DENSE (AUC = 0.9 [0.8, 0.9], -10%) was noninferior to ECV (AUC = 0.8 [0.7, 0.9], 42%) (P= 0.132) and superior to feature-tracking (AUC = 0.7 [0.7, 0.8], -13%) (P < 0.05). For MVO detection, circumferential strain with DENSE (AUC = 0.8 [0.8, 0.9], -12%) was superior to ECV (AUC = 0.8 [0.7, 0.8] 34%) (P < 0.05) and feature-tracking (AUC = 0.7 [0.6, 0.7] -21%) (P < 0.05). Data Conclusion Circumferential strain with DENSE is a functional measure of infarct severity and may remove the need for gadolinium contrast agents in some circumstances. Level of Evidence 2 Technical Efficacy Stage 5