International Post-PCI FFR Extended Registry

Percutaneous coronary intervention (PCI) is a standard treatment strategy for coronary artery disease (CAD). With the presence of myocardial ischemia, PCI reduces the risks of death, myocardial infarction (MI), and revascularization compared to medical therapy. However, the risk of future clinical events remains high, and about 10% of patients experienced further cardiovascular events after PCI. Several factors are associated with these poor outcomes. Well-known patient-related risk factors are diabetes mellitus, chronic kidney disease, left ventricular dysfunction, previous MI, and presentation with acute coronary syndrome. Procedure-related factors, such as stent under expansion, malposition, edge dissection, the number of the used stent, and total stent length, are also related to poor prognosis after PCI. Recent studies reported that fractional flow reserve (FFR) after coronary stenting, or post-PCI FFR, was associated with future clinical outcomes after PCI, and low post-PCI FFR value was associated with procedural factors. However, optimal cut-off values of post-PCI FFR ranged widely, from 0.86 to 0.96, and some studies reported the limited prognostic value of post-PCI FFR. This might result from differences in study populations, the definition of outcomes, type of stent used, and distribution of included vessels among previous studies. Previously, the investigators incorporated previous data into the International Post-PCI FFR registry and demonstrated the prognostic value of post-PCI FFR using the machine learning technique. However, the results were based on the two years follow-up of patients after PCI, and the prognostic value of post-PCI FFR in long-term outcomes is still uncertain. Therefore, the investigators planned to extend the International Post-PCI FFR registry to define the long-term prognostic implication of post-PCI FFR.