The Shockwave intravascular lithotripsy (IVL) system handled long severely calcified coronary lesions with the same safety and efficacy as shorter severely calcified coronary lesions, according to an analysis presented Friday at CRT 2021 Virtual.
Severe calcification in target lesions makes it difficult to deliver and deploy stents and impairs stent expansion, which is a significant predictor of stent thrombosis and restenosis.
Disrupt CAD III, a prospective, single-arm, multicenter investigational device exemption study, demonstrated the safety and effectiveness of IVL (Shockwave Medical, Santa Clara, California) in severely calcified de novo coronary lesions. It met both its primary safety endpoint (30-day freedom from major adverse cardiovascular events [MACE]: 92.2%, lower bound of the 95% confidence interval [CI], 89.9%, exceeded the prespecified performance goal of 84.4%) and primary effectiveness endpoint (procedural success: 92.4%, lower bound of the 95% CI, 90.2%, exceeded the prespecified performance goal of 83.4%), according to results published in December in the Journal of the American College of Cardiology.
This study led to the U.S. Food and Drug Administration granting premarket approval Tuesday to the IVL as treatment for severely calcified cardiovascular disease.
Matthew J. Price, MD, of Scripps Clinic, San Diego, presented a substudy of DISRUPT CAD III on Friday at CRT 2021 Virtual. He focused on the treatment of long severely calcified coronary lesions. Specifically, the subanalysis examined the safety and effectiveness of IVL in lesions 25 mm or longer.
IVL sends acoustic pressure waves, 1 per second, through tissue with an effective pressure of about 50 atmospheres to fracture both superficial and deep calcium.
The main study’s intention-to-treat population of 384 patients was stratified by median lesion length to <25 mm and ≥25 mm. Three patients were excluded from the subanalysis because there was no pre-procedural lesion length assessment by an angiographic core laboratory.
The patients in both groups were well-matched, with an average age of approximately 71 years and high rates of hypertension and hyperlipidemia. The only difference was that patients with longer lesions were more likely to be men (81.1% vs. 71.7% in the short-lesion group; p=0.04). Also, patients in the long-lesion group had a higher percentage of lesions in the right coronary artery (35.8% vs. 22.5%) and a lower percentage in the left circumflex artery (7.4% vs. 18.3%).
In the long-lesion group, the procedure time was longer (66±32 minutes vs. 52±26 minutes, p<0.0001), and more IVL pulses (79±32 vs. 59±28, p<0.0001) and stents (1.5±0.6 vs. 1.1±0.3, p<0.0001) were needed.
The groups were statistically similar for both the primary effectiveness endpoint, procedural success (short-lesion group 94.2%, long-lesion group 90.5%, p=0.18), and the primary safety endpoint, freedom from 30-day MACE (94.2% vs. 90.0%, p=0.18).
Price concluded by noting that the long-lesion group “included a remarkably complex lesion subset” with a mean lesion length of 37 mm and a mean calcium length of 55 mm. In addition to the similar safety and effectiveness between the short- and long-lesion groups, Price said there were no episodes of abrupt closure, slow flow or no-reflow immediately after IVL treatment or stent deployment in the long-lesion group.
“Therefore,” he said, “IVL is an attractive therapy to address severely calcified lesions across a spectrum of lesion length.”
Price reports being a consultant for, and receiving honoraria from, Shockwave Medical and other device companies. Disrupt CAD III was supported by Shockwave Medical.
CRT 2021 Virtual takes place Fridays and Saturdays through April 24. On-demand content from the meeting is available here.