[Discordant pattern, visual identification of myocardial viability with PET]

PET (positron emission tomography) as a non-invasive imaging method for studying cardiac perfusion and metabolism has turned into the gold standard for detecting myocardial viability. The utilization of 18 FDG as a tracer for its identification permits to spot the use of exogenous glucose by the myocardium segments. By studying and comparing viability and perfusion results, for which the latter uses tracers such as 13N-ammonia, three different patterns for myocardial viability evaluation arise:. transmural concordant pattern, non-transmural concordant pattern, and the discordant pattern; the last one exemplifies the hibernating myocardium and proves the presence of myocardial viability. The importance of its detection is fundamental for the study of an ischemic patient, since it permits the establishment of and exact diagnosis, prognosis, and the best treatment option. It also allows foreseeing functional recovery of the affected region as well as the ejection fraction rate after revascularization treatment if this is determined as necessary. All these elements regarding viability are determinant in order to reduce adverse events and help improving patients' prognosis.