Saved myocardium in acute ST-segment elevation myocardial infarction post-reperfusion: Analysis by cardiac magnetic resonance

Objective: To quantify by cardiovascular magnetic resonance the salvaged myocardium in the myocardium supplied by the infarct-related artery in reper-fused and non-reperfused patients with a first ST-segment elevation myocardial infarction (STEMI). Patients and Method: Twenty-five patients with a first STEMI (non-reperfused, ten patients; thrombolysis, ten patients; primary angioplasty, five patients) underwent cardiac magnetic resonance imaging 3 to 6 days after coronary angiography. Myocardial salvage and myocardial salvage index were quantified. Results: Peak troponin values were lower in patients with primary angioplasty than in thrombolysis and non-reperfused patients (14,1 ng/mL versus 515,4 ng/mL and 123,1 ng/mL, respectively; p < 0,007) and smaller infarct size (14,1 g versus 31,2 g and 31,5 g, respectively; p < 0,003). Myocardial salvage mass and myocardial salvage index were higher in patients with primary angioplasty than in thrombolysis and non-reperfused patients (27,4 g versus 4,7 g and 2,1 g, respectively; p < 0,003) and (65,2% versus 14,9% and 6,6%, respectively; p < 0,0001). Conclusions: The results of this study indicate the need to reassess the performance of coronary angioplasty and stent implantation in patients with a first STEMI, thrombolysis, and non-thrombolysis without prior myocardial viability studies. Cardiac magnetic resonance allows the quantification of salvaged myocardium and could be considered an emerging clinical application for the early evaluation of myocardial viability.