Directional coronary atherotomy - experimental use of single-blade cutting balloon

In the drug-eluting stent era, minimum stent diameter is one independent predictor of restenosis. Some plaque modification is necessary before stenting to obtain the minimum stent diameter, but plaque modification using current devices is difficult in certain lesions, such as those in eccentric small vessels. As a potential solution to this problem, we investigate the usefulness of a single-blade Cutting Balloon (SCB) in this study.

We used the SCB in 5 porcine coronary arteries (2 LAD, 1 LCx and 2 RCA) to investigate the feasibility of directional atherotomy. We also tried the kissing balloon technique (KBT) with the SCB in 3 bifurcations from the same arteries. We used intravascular ultrasound (IVUS) guidance to position and direct the atherotome using the side holes of the guiding catheter as a marker. We also assessed plaque modification with IVUS before and after percutaneous coronary intervention and took coronary sections to inspect tissue pathology after the procedures.

In all 5 porcine models, we were able to view and confirm the success and accuracy of our incision on IVUS. We were successfully able to control the direction of the blade without balloon rupture during KBT. We were also able to verify the directional incisions afterwards from examination of tissue pathology.

Our investigation suggests that this SCB may be used effectively for directional atherotomy. We can accurately modify the plaque with this device by correctly positioning the blade to choose the direction of the incision. The next challenge is to improve the reliability of the device and to move on to in vivo trials.