An intravascular lithotripsy catheter for peripheral artery disease

Many CLI patients do not respond well to endovascular treatment, especially when calcium is present with blockages reoccurring frequently, often requiring reinterventions or even limb amputation.

Intravascular Lithotripsy is an innovative therapy designed to treat calcified leg artery blockages with lithotripsy - sonic pressure waves historically used to treat patients with kidney stones.

The technology minimises trauma within the artery by delivering pulsatile sonic pressure waves locally that fracture calcium inside the artery wall but pass through surrounding soft vascular tissue in a safe manner.

Shockwave S4 complements the existing larger-diameter IVL catheter, which has been available in Europe since 2015 for the treatment of calcified peripheral disease from the iliac arteries down to the knee.

Shockwave S4 features many design improvements to enhance deliverability in small, distal vessels, including a longer, hydrophilic shaft, a lower crossing and tip profile, smaller lithotripsy emitters and new stronger balloon material.

“The new Shockwave S4 IVL catheter has the potential to change the treatment paradigm for our most difficult-to-treat patients – those with CLI,” said Prof Marianne Brodmann, M.D., of the Medical University of Graz.

“Acute and long-term outcomes for these patients remain poor, especially for patients with vascular calcification who have a five-fold greater risk of major amputation. Vascular calcium is prevalent in CLI patients and frequently resides deeper in the artery wall, making endovascular treatment more challenging. Intravascular Lithotripsy has the potential to reach and safely treat this deep wall calcium, thereby improving the ability to open these vessels in an effective and predictable manner, while still preserving future treatment options.”

IVL has been demonstrated to be a safe and effective treatment for femoropopliteal arteries in the DISRUPT PAD I and II studies and for infrapopliteal below-the-knee arteries in the DISRUPT BTK study, which demonstrated the feasibility of IVL below-the-knee.

Acute performance in a patient population with advanced peripheral artery disease, most suffering from critical limb ischemia, showed low percent residual stenosis (26%) and low vascular complications, including no perforations, distal embolisation, reflow complications or abrupt closure and only one grade B dissection.

There were no major adverse events including death, myocardial infarction, target limb revascularisation or amputation through 30 days.

The Shockwave S4 IVL system, similar to other IVL systems, includes a compact, battery-powered generator, a simple and quick hand-held connector cable with a single therapy delivery button and an intuitive catheter, which houses an array of lithotripsy emitters enclosed in an integrated balloon. The catheter is delivered to a lesion similar to standard interventional techniques.

“The treatment of CLI is commonly compounded by the presence of complex medial calcium, deep in the wall of below-the-knee arteries, and clearly remains a significant unmet clinical need based on our customers’ feedback,” said Doug Godshall, CEO of Shockwave Medical.

“Representing our commitment to optimising outcomes and tailoring our IVL therapy for specific use cases across the vasculature, Shockwave S4 was designed specifically to address the challenges of CLI. We look forward to introducing this novel technology over the coming months to provide our clinicians with a tool to help them achieve a high degree of luminal gain with minimal complications and greatly simplify these complex CLI procedures.”

Shockwave S4 catheters are now commercially available only in Europe and New Zealand. The larger-diameter peripheral Intravascular Lithotripsy catheters are commercially available in both the United States and Europe.