Patients with three-vessel coronary disease whom the Heart Team decide are in equipoise between surgical revascularization or PCI intervention, undergo physiologically guided stenting. The SYNTAX II clinical risk calculator is used to determine equipoise. All major vessels undergo pressure wire assessment using the iFR-FFR hybrid approach, and only those positive for ischaemia undergo stenting. Intravascular ultrasound is used to ensure optimal stent delivery. Clinical outcomes will be compared to a historical surgical cohort from SYNTAX-I study. An example of a patient enrolled into the SYNTAX-II study is shown in this video. The instantaneous wave-free ratio can also be calculated on a beat-to-beat basis. If performed during the slow withdrawal of a pressure wire (referred to as 'pullback') under resting conditions, it is possible to plot the change of iFR or trans-stenotic gradient over the wave-free period throughout the vessel. This can help identify focal and diffuse coronary disease potentially amenable to revascularisation. An example of pullback in clinical use can be seen in this video. The pressure wire data can be co-registered with the angiographic findings to aid ease of interpretation. With mechanised pullback approaches which move the pressure wire at a fixed speed, the physiological length of a stenosis can be determined. With advanced live co-registration this is also feasible with during manual pullback. Advanced computer processing can utilise iFR-pullback data to predict the hemodynamic consequences of performing percutaneous coronary intervention (PCI) to a chosen segment of the coronary vessel. The predicted iFR values produced by the virtual-PCI on the iFR-pullback are closely related to those observed after PCI in the coronary vessel. This predictive capacity may provide added advantage to Interventional Cardiologists when assessing multiple coronary stenoses in a single vessel and planning the treatment approach. iFR-pullback technologies are undergoing evaluation in European centres. Alternative iFR computation systems have been proposed, for example incorporating part of systole into the definition of diastole and optionally different time-shifts between Pd and Pa signals, yielding unsatisfactory results. The same datasets reanalysed using the standard algorithms confirm the mainstream findings. Various explanations have been proposed.