Acute myocardial infarction: myocardial salvage assessment

Primary coronary revascularization by means of percutaneous coronary intervention(PCI)is a highly effective treatment of acute myocardial infarction re-establishing coronary perfusion and stopping the ongoing necrosis in the dependent myocardium.Single-photon emission computed tomography(SPECT)is the most widely used modality assessing myocardial salvage as the difference between the acute perfusion defect before intervention and the remaining scar size measured in a second scan several days after the event.SPECT allows quantification of area at risk(AAR)and final infarct size(FIS)by tracer injection prior to revascularization and after 1 month,respectively.SPECT provides the most validated measure of myocardial salvage and has been utilized in multiple randomizedclinical trials.However,SPECT is logistically challenging,expensive,and includes radiation exposure.More recently,a large number of studies have suggested that cardiac magnetic resonance(CMR)can determine salvage in a single examination by combining measures of myocardial oedema in the AAR exposed to ischaemia reperfusion with FIS quantification by late gadolinium enhancement.