ABSTRACT
Percutaneous coronary intervention (PCI) of calcified coronary arteries is associated with poor outcomes. Poorly modified calcified lesion hinders the stent delivery, disrupts drug-carrying polymer, impairs drug elution kinetics and results in under-expanded stent (UES). UES is the most common cause of acute stent thrombosis and in-stent restenosis after PCI of calcified lesions. Angiography has poor sensitivity for recognition and quantification of coronary calcium, thereby mandating the use of intravascular imaging. Intravascular imaging, like intravascular ultrasound and optical coherence tomography, has the potential to accurately identify and quantify the coronary calcium and to guide appropriate modification device before stent placement. Available options for the modification of calcified plaque include modified balloons (cutting balloon, scoring balloon and high-pressure balloon), atherectomy devices (rotational atherectomy and orbital atherectomy) and laser atherectomy. Coronary intravascular lithotripsy (IVL) is the newest addition to the tool box for calcified plaque modification. It produces the acoustic shockwaves, which interact with the coronary calcium to cause multiplanar fractures. These calcium fractures increase the vessel compliance and result in desirable minimum stent areas. Coronary IVL has established its safety and efficacy for calcified lesion in series of Disrupt CAD trials. Its advantages over atherectomy devices include ease of use on workhorse wire, ability to modify deep calcium, no debris embolization causing slow flow or no-flow and minimal thermal injury. It is showing promising results in modification of difficult calcified lesion subsets such as calcified nodule, calcified left main bifurcation lesions and chronic total occlusion. In this review, authors will summarize the mechanism of action for IVL, its role in contemporary practice, evidence available for its use, its advantages over atherectomy devices and its imaging insight in different calcified lesion scenarios.
Shock the rock with coronary intravascular lithotripsyPresence of coronary calcium during stenting is associated with the risk of stent under expansion. It's imperative to adequately modify this coronary calcium before placing the stent. Till recent past, the most effective method for calcium modification is debulking it with rotational artherectomy, which is associated with the risk of coronary perforation, slow flow or abrupt vessel closure. Recently, a balloon-based lithotripsy device has established its safety and efficacy for treating such lesions. Coronary intravascular lithotripsy (IVL) is an easy to use calcium modification device and is associated with almost negligible complications, when compared with artherectomy devices. In this review, we will discuss the mechanism of IVL action and its use in different scenarios of calcified coronary artery disease.