Intravascular Lithotripsy for Severely Calcified Coronary Arteries
Intravascular lithotripsy uses acoustic pressure waves to modify calcium inside the blood vessels, increasing the compliance of the vessel and facilitates stent deployment . The device takes care of one of the important night mares of an interventionalist, the calcified coronaries!
Disrupt CAD III was a prospective multicenter study for the regulatory approval of intravascular coronary lithotripsy . Optical coherence tomography (OCT) was used to assess the mechanism of modification of calcium in a substudy. Primary safety endpoint of Disrupt CAD III was freedom from major adverse cardiovascular events (MACE) of cardiac death, myocardial infarction or target vessel revascularization at 30 days. Procedural success was the primary effectiveness endpoint of the study. The trial had 431 patients enrolled from 47 sites across 4 countries. Freedom from MACE was 92.2% of patients and procedural success was 92.4%. Mean calcified segment length was 47.9 mm and mean thickness of the calcium was 0.96 mm at the site of maximum calcification. Multiplane and longitudinal calcium fractures were demonstrated in 67.4% of the lesions by OCT after intravascular lithotripsy. Thus Disrupt CAD III study demonstrated the safety and effectiveness of intravascular lithotripsy in facilitating stent implantation in severely calcified coronary arterial lesions.
A smaller previous study had reported the real-world experience on shockwave intravascular lithotripsy for calcified coronary lesions . Their report had 26 patients who have intravascular lithotripsy prior to stent deployment. 14 patients had acute coronary syndrome, 11 had stable angina and in one patient it was prior to transcatheter aortic valve implantation. Angiographic success was obtained in all cases with no procedural complications. Half of the intravascular lithotripsy procedures were in the left anterior descending coronary artery. In 58% cases, intravascular lithotripsy was used upfront while in the remaining cases, it was bail-out after suboptimal initial balloon pre-dilatation. In the acute coronary syndrome cases, 71% were for the perceived culprit lesions while 29% were for stage percutaneous coronary intervention to severe non-culprit lesions.