Can Multimodal Invasive Imaging Be Used to Predict Periprocedural Myocardial Infarctions?

M ore than 1 million percutaneous coronary interventions (PCIs) are performed per year in the United States. Although technological advances have significantly improved outcomes following PCI, 5% to 44% of PCI patients still experience periprocedural myocardial infarction (PMI). PMI can be either macro-sized (coronary dissection or occlusion of a side branch) or microvascular such as distal embolization and/or microvascular plugging. PMIs have recently been defined as Type 4a: cardiac troponin (cTn) levels >5 elevation above the 99th percentile upper reference limit (URL), but only if the baseline cTn levels were normal (#99th percentile URL) (1). In addition to the elevated cTn levels, at least 1 of the following must be present: 1) symptoms suggestive of myocardial ischemia; 2) new ischemic electrocardiographic (ECG) changes; 3) angiographic loss of patency of a coronary artery or side branch; or 4) imaging demonstration of new loss of viable myocardium or new regional wall motion abnormality (1). Despite the extensive literature on this topic, most studies only utilize the enzyme definition of type 4a infarction—rarely are angina, ECG changes, and new wall motion abnormalities taken into account. Although the universal definition of type 4a myocardial infarction (MI) requires