Femoropopliteal segment calcification can generate complications for both preparation and execution of endovascular therapies for patients with peripheral artery disease. It can produce suboptimal vessel expansion associated to higher risk of dissection or perforation. These adverse effects can affect procedure durability in the long term.
Studies on the use of drug coated balloons to treat patients with diffuse calcification had shown lower patency at long term when compared against patients with non-calcified lesions.
Intravascular Lithotripsy (IVL) has surged as an alternative treatment for these cases. It uses multiple emitters that provide pulsatile acoustic pressure energy to fracture superficial and deep calcium deposits without affecting local tissue. It would facilitate correct target vessel preparation by improving luminal compliance and therefore facilitate endovascular treatment.
The aim of this study was to report on primary patency at one and two years of patients included in the Disrupt PAD III, a randomized study aimed at assessing the safety and efficacy of IVL vs percutaneous transluminal angioplasty (PTA) as preparation for a definite strategy.
It included patients with leg claudication or rest pain (Rutherford 2-4) and angiographic evidence of ≥70% stenosis in the superficial femoral and/or popliteal artery, lesions up to 180mm (or 100mm in case of CTO), with a reference diameter of 4-7mm and moderate to severe calcification.
153 patients were randomized to IVL and 153 to ATP, followed by a definite treatment with drug coated balloon (DCB) or in case of failed preparation before DCB, a provisional stenting.
Primary effectiveness end point was definite procedural success defined as ≤30% residual stenosis with no flow limiting dissection. Secondary endpoint was primary patency at 1 year, defined as freedom from clinically driven target lesion revascularization and freedom from restenosis as determined by doppler ultrasound or angiogram.
Primary effectiveness end point showed higher procedural success in the IVL arm compared against ATP (65.8% vs 50.4%, P=0.065). It was also observed, after one year, superior primary patency of no statistical significance (80.5% vs 68%, P=0.17). Multivariable analyzis showed independent predictors of primary patency were sue of IVL, age over 75, and non-CTO lesions.
Primary patency was more in favor of IVL at 2 years (74.4% vs 57.7%), with no major adverse events. (IVL 0% vs ATP%, P=0.15).
The Disrupt PAD III is the most important randomized study on the use of IVL to treat calcified lesions; it looks at preparation with ShockWave device, at definite strategy (DCB or provisional stenting), showing superior primary patency and procedural success. The limitation of this study, when looking at superiority, is not to be able to compare against other calcium modifying devices such as atherectomy devices. Failure to compare limits our options and prevents us from establishing a gold standard to treat calcifications.
Dr. Omar Tupayachi.
Member of the Editorial Board of SOLACI.org.
Subscribe to our weekly newsletter
Get the latest scientific articles on interventional cardiology