Side branch protection with hydrophilic polymer coated guide wire during cutting balloon angioplasty of a bifurcated lesion.

Cutting balloon angioplasty (CBA) was performed in a patient with in-stent restenosis (ISR) which had an important side branch. We used a hydrophilic polymer-coated guide wire for side branch protection during CBA. After CBA was successfully performed, the cutting balloon and guide wire were microscopically examined and proven to have suffered minor damage which, in itself, did not disturb the procedure. Hydrophilic polymer-coated wire might be an effective and safe choice for ISR which needs to be treated by CBA while protecting an important side branch.