Scout post-PCI instantaneous wave-free ratio as a driver of functional complete

Abstract Aims Physiology assessment by means of instantaneous wave-free ratio (iFR) is non-inferior to fractional flow reserve for the assessment of intermediate coronary lesions that are candidates to percutaneous coronary intervention (PCI). However, in pivotal trials assessing iFR, tandem coronary lesions (i.e. two serial lesions located in the same coronary artery) were excluded. In addition, the role of iFR after PCI as a way to optimize its success is poorly understood, particularly in the context of ST-segment elevation myocardial infarction (STEMI) with multivessel disease and tandem stenoses. We describe an illustrative case of post-PCI iFR in a STEMI patient with multivessel disease that led to a significant change in the revascularization strategy. Methods A 71-year old man presented with infero-lateral STEMI and received PCI with 1 drug-eluting stent (DES) 2.25 × 18 mm on the distal right coronary artery. The left coronary artery presented a 30–40% stenosis of the proximal left circumflex (LCX) and a 90% bifurcation stenosis of the mid portion of the same artery. PCI of the distal lesion was performed with implantation of 1 DES 3.0 × 22 with flaring of the stent at the level of the side branch and proximal optimization technique. Post-PCI iFR of the LCX was performed to assess the success of the procedure, with a value of 0.74. To understand the relative contribution of the two tandem stenoses, a pullback of the iFR wire was performed, which showed an unexpectedly small jump of the pressure when the wire was between the two lesions (0.80). Results As such, the significant contribution of the proximal lesion was unravelled, which led to implantation of a second DES 4.0 × 26 mm, partially overlapping with the previously implanted DES. Post-PCI iFR confirmed the complete success of the procedure (1.00). Conclusions In the context of complete revascularization for STEMI presenting with non-infarct related artery tandem stenoses, post-PCI physiology contributes to unravel the relative contribution of low-grade angiographic stenoses corresponding to functionally significant atherosclerosis left untreated. This case example illustrates the emerging procedural value of post-PCI iFR in achieving the goal of complete functional revascularization.