Why is this study important?  

There is limited long-term data available to provide treatment guidance for patients with severe femoropopliteal calcification as this challenging population is often excluded from clinical trials. 
Intra vascular lithotripsy (IVL) demonstrated safety and durability in the treatment of heavily calcified femoropopliteal lesions compared to PTA. 

What question was this study supposed to answer?   

The endovascular treatment of calcified peripheral artery lesions may be associated with suboptimal vessel expansion, increased complication risk, and reduced long-term patency. Disrupt PAD III 30-day data demonstrated the safety and effectiveness of IVL versus Percutaneous balloon angioplasty (PTA) as a vessel preparation strategy prior to definitive treatment with Drug Coated Balloon or stenting in patients with calcified femoropopliteal lesions. The primary endpoint from the Disrupt PAD III randomized controlled trial was procedural success, this was superior in patients receiving vessel preparation with IVL compared to balloon angioplasty. The trial now sets to answer another question; Is IVL a durable therapy in the treatment of calcified femoropopliteal lesions? 

What did the study show?   

The one-year data presented at SCAI 2022 demonstrated the consistent safety and durability of IVL in treating Heavily calcified femoropopliteal lesions. The powered secondary endpoint of primary patency at 1-year was significantly higher in the IVL arm (80.5% vs. 68.0%, p=0.017) and remained favorable through two years (Kaplan-Meier estimate: 74.4% vs. 57.7%, p=0.005). Freedom from clinically driven-TLR (IVL: 95.7% vs PTA: 98.3%, p=0.94) and restenosis (IVL: 90.0% vs PTA: 88.8%, p=0.48) were similar between the two groups at 1-year. Moreover, bail-out stenting was significantly lower in the IVL group (4.6% vs 18.3%, p<0.0001) which can help preserve future treatment options in claudicants with severe femoro-popliteal calcification. 

This randomized trial has several strengths, including angiographic and duplex ultrasonography core laboratory and Clinical Events Committee adjudication, as well as blinding of patients and duplex ultrasound core laboratory readers. However, Investigators and research staff were not blinded to treatment assignment due to obvious differences in the study devices. 

It remains to be seen how IVL compares to other modalities such as atherectomy and whether the primary patency remains superior in longer term follow-up.  

All editors: Luai K. Tabaza, MD, FSCAI