[Management of stent under-expansion].

Stent under-expansion represents a negative prognostic factor, because of the risk to develop intrastent restenosis and stent thrombosis. It is often due to excessive calcium burden at the target lesion level. The list of devices available for the treatment of stent under-expansion includes super high-pressure non-compliant (NC) balloons, excimer laser and intravascular lithotripsy.