Intravascular lithotripsy for calcific coronary and peripheral artery stenoses

Heavily calcified lesions may be difficult to dilate adequately with conventional balloons and stents, which causes frequent periprocedural complications and higher rates of target lesion revascularisation (TLR). High-pressure non-compliant balloon angioplasty may be of insufficient force to modify calcium and, even when successful, may be limited in its ability to modify the entire calcified lesion. Scoring and cutting balloons hold theoretical value but data to support their efficacy are lacking and, because of their high lesion crossing profile, they often fail to reach the target lesion. Rotational and orbital atherectomy target superficial calcium; however, deep calcium, which may still impact on vessel expansion and luminal gain, is not affected. Intravascular lithotripsy (IVL), based on lithotripsy for renal calculi, is a new technology which uses sonic pressure waves to disrupt calcium with minimal impact to soft tissue. Energy is delivered via a balloon catheter, analogous to contemporary balloon catheters, with transmission through diluted ionic contrast in a semi-compliant balloon inflated at low pressure with sufficient diameter to achieve contact with the vessel wall. With coronary and peripheral balloons approved in Europe, peripheral balloons approved in the USA and multiple new trials beginning, we review the indications for these recently introduced devices, summarise the clinical outcomes of the available trials and describe the design of ongoing studies.