Resolving chronic stent under-expansion in calcified lesions by intravascular lithoplasty.

Severe coronary calcification is a common cause for stent under-expansion, which is associated with an increased risk of stent thrombosis and restenosis. Presently the devices for treatment of under-expanded stent due to severe calcification are rotational atherectomy and high-pressure non-compliant balloons with the limitation of potential balloon rupture and perforation risk. We report on a series of seven successful treatments of chronically under-expanded stents due to severe calcification using shockwave coronary intravascular lithoplasty (IVL). Our report suggests that IVL is a feasible and safe tool for such chronically under-expanded stents. <Learning objective: Severe coronary calcification is a common cause for stent under-expansion, which is associated with an increased risk of stent thrombosis and restenosis. Presently the devices for treatment of under-expanded stent due to severe calcification are rotational atherectomy and high-pressure non-compliant balloons. Our report suggests that intravascular lithoplasty is a feasible and safe tool to expand chronically under-expanded stents due to severe calcification, and that it is superior to rotational atherectomy and high-pressure balloons.>.