The use of percutaneous coronary intervention (PCI) as a primary treatment for acute myocardial infarction (AMI) has contributed to save lives. But, in addition to this, it has generated new opportunities to study the culprit and non-culprit arteries with intracoronary imaging during and after reperfusion treatments, and thus to get a richer view of this syndrome. From this perspective, intracoronary imaging has contributed to our knowledge of AMI in a number of ways: it has complemented the available information on the substrate of AMI with in-vivo observations, reinforcing the current pathophysiological paradigm on this entity; it has allowed longitudinal documentation on the reparative vascular processes at the culprit lesion over the months and years following the acute event; it has generated valuable observations on the vascular responses to interventions performed during primary PCI, such as implantation of drug eluting stents (DES); it has been used to guide or monitor specific interventions, either pharmacological agents like antithrombotics or devices like thrombectomy catheters or stents, at the culprit stenosis of AMI; and it has revealed the characteristics of concomitant atheromatosis in non-culprit vessels. In this article, we review the available literature on these different aspects.