Interference between pressure-wire and deployed coronary stents: Insights from a bench test

Abstract Background While several complications related to pressure-wire (PW) have been reported, mechanistic justification has not always been offered. Furthermore, interference between a PW and a protruding side-branch stent has not been previously reported. The purpose of this study was to evaluate interference between PW-pullback from a main-branch with a protruded ostial stent deployed in a side-branch. Methods In a polyurethane bifurcation vessel model, PW-pullback was performed in a main-branch following protruded ostial stenting in a side-branch. Tested PWs included PressureWire X, Comet, OptoWire, and Verrata. For each PW, pullback was performed through the same proximal cell of the protruded stent 20 times. Interference during PW-pullback was objectively analyzed with a fiberscope placed at the distal main-branch and classified into 3 grades according to the interaction with stent strut. Results There were significant differences in the rate of interference between the PWs. No-interference, interference without strut traction, and interference with strut traction (i.e. stent deformation) were observed as follows: 17/20, 3/20, and 0/20 in PressureWire X; 19/20, 1/20, and 0/20 in Comet; 8/20, 10/20, and 2/20 in OptoWire; and 13/20, 2/20, and 5/20 in Verrata, respectively (p for any differences: Conclusions PW-pullback in the main-branch after side-branch ostial stenting should be carefully performed to avoid stent deformation. Consideration on the specific mechanical features of the PW is also essential.