Background: Calcified bifurcation stenoses continue to pose a particular challenge for percutaneous coronary intervention (PCI). Prior to stent implantation it is imperative to achieve sufficient plaque modulation to prevent stent underexpansion, which is associated with an impaired clinical outcome. Calcified plaques are more common in bifurcation stenoses and are associated with a higher rate of stent underexpansion as well as a greater risk of in-stent restenosis than non-bifurcation stenoses.

Purpose: The aim of this ongoing study is to evaluate the safety and efficacy of intravascular lithotripsy (IVL) in the treatment of severely calcified bifurcation lesions using optical coherence tomography (OCT).

Methods: IVL was performed in 16 patients with angiographically moderate to severe calcification (according to American Heart Association definition) of a clinically relevant bifurcation stenosis. OCT was performed immediately post-procedurally to compare lumen/stent areas, and vessel wall configuration. Patient clinical data and procedural characteristics were collected additionally. 

Results: The mean patient age was 76±7 years. All patients were symptomatic with stable angina. Pre-procedural minimal lumen diameter was 1.05±0.69 mm, mean lumen diameter was 1.69±0.49 mm, and maximum diameter stenosis was 84±16% as determined by quantitative coronary angiography (QCA). Post-procedural minimal stent area in the treated segment as determined by OCT was 3.95±0.73 mm². Minimal stent area was located in the side branch in 13 of 16 cases (81.3%) and in the bifurcation area in 3 of 16 cases (18.7%; p=0.013). Minimal stent area in the main branch was 5.91±1.30 mm². Stent expansion, defined as quotient of minimal stent area divided by angiographic reference vessel area, did not differ significantly when comparing main vessel (84±6%) and side branch (83±8%; p=0.88). There were no periprocedural adverse events. During clinical follow-up, there did not occur any adverse events by now (mean follow-up duration 6±4 months).

Conclusion: IVL is a safe and effective treatment option for plaque modulation in severely calcified bifurcation lesions.