Patients who have peripheral arterial disease often need a procedure to open up their diseased arteries. One of the common reasons why these procedures fail is the presence of calcium on the artery walls. A new treatment called intravascular lithotripsy was recently introduced in the NHS. Intravascular lithotripsy is meant to break down the calcium on diseased artery walls. This multicentre prospective cohort study aims to investigate the effect of intravascular lithotripsy on the patency of a lower limb atherosclerotic lesion in patients with symptomatic PAD treated in the NHS, six months after the procedure.

Secondary objectives:

1. To investigate whether patients require further angioplasty or other procedures in the six months post intravascular lithotripsy.

2. To investigate whether patients suffer any of the following complications; stroke, transient ischaemic attack, myocardial infarction, or lower limb amputation in the six months post intravascular lithotripsy.

3. To investigate whether patients are readmitted to hospital for PAD related treatment in the six months post intravascular lithotripsy.

4. To investigate whether changes in atherosclerotic plaque consistency are observed within three days post intravascular lithotripsy

5. To gather information about how and why clinicians decided upon this choice of treatment over alternative methods available in the NHS.

Patients aged over 18 years with peripheral arterial disease who are undergoing intravascular lithotripsy (IVL) can participate, with a planned sample size of 60 patients, with a 6-month follow-up.

Once a participant has consented to take part, the study team will collect information about their medical and surgical history as well as clinical presentation. Further, details regarding their intravascular lithotripsy procedure will be documented and the participant will be observed for 12 months. Major complications and further surgical procedures will be documented. Participants will also be asked if they wish to take part in a sub-study, where the study team will assess the composition of the atheromatic plaque 3 days after the intravascular lithotripsy procedure. This will be done using a computed tomographic scan, limited to the region treated using intravascular lithotripsy.

The primary outcome measure is patency of the treated arterial atherosclerotic lesion based on duplex ultrasound measurement at six months after the procedure has taken place. Secondary outcome measures include additional treatments during the index procedure, including other endovascular treatments, and all complications during the in-hospital stay, as well as the duration of in-hospital stay. Secondary outcome measures 30-days after the procedure and at 6-months include:

• Re-intervention (open or endovascular – including re-intervention for other indications)
• Lower limb amputation
• Change in the treated atherosclerotic plaque consistency for patients requiring re-intervention or having additional imaging due to re-stenosis
• Patients’ quality-of-life.

Investigators:

Mr Patrick Coughlin, Mr Daniel Carradice, Mr Hany Zayed, Mr Said Abisi, Dr Narayanan Thulasidasan, Dr Neghal Kandiyil, Dr Raghu Lakshminarayan, Mr Robert SM Davies, Professor Robert D Sayers, Mr Soroush Sorabi

Trial participating centres:

• University Hospitals of Leicester
• St Thomas’ Hospital
• Addenbrooke’s Hospital
• Hull Royal Infirmary
• Glan Clwyd Hospital