Central Illustration.

Noninfarct T1 and Infarct T1 Immediately After STEMI Predict Long-Term MACE

Current assessment of myocardial tissue in patients with ST-segment elevation myocardial infarction (STEMI) focuses on the infarcted myocardium, which is the area with late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). This study describes, for the first time, the prognostic significance of myocardial injury in the entire heart using CMR T1-mapping, in both infarcted and noninfarcted myocardium (area without LGE, which includes the remote myocardium). A “lower” infarct T1 (≤1,300 ms, reflecting the presence of microvascular injury such as MVO) and a high noninfarct T1 (>1,250 ms) measured at 2 days after STEMI are associated with long-term MACE (new diagnosis of symptomatic heart failure or sustained ventricular arrhythmia or cardiac death). MACE = major adverse cardiac events; MVO = microvascular obstruction.