LimFlow announced on 1 August 2017 publication of positive results from the pilot study of the LimFlow Percutaneous Deep Vein Arterialization System (pDVA) in the July issue of the Journal of Endovascular Therapy. The paper is entitled “Midterm Outcomes from a Pilot Study of Percutaneous Deep Vein Arterialization for the Treatment of No-Option Critical Limb Ischemia.” The LimFlow System is a novel, purely percutaneous device for the treatment of end-stage critical limb ischaemia (CLI) when all other revascularisation efforts have been exhausted.
The authors conclude that, “pDVA is an innovative approach for treating no-option CLI and represents an alternative option for the ‘desert foot,’ potentially avoiding major amputation. Our results demonstrate its safety and feasibility, with promising early clinical results in this small cohort.”
The prospective, open-label, single-arm pilot study was led by primary investigator Steven Kum, of Changi General Hospital, Singapore, and encompassed seven no-option CLI patients with an average age of 85. All patients had diabetes and were Rutherford class 5 or 6, with 86% (6 of 7) also classified as WIfI (Wound Ischemia foot Infection) “high risk”.
All primary safety endpoints were met in 100% of patients, with no deaths, above-the-ankle amputations or major reinterventions at 30 days. All patients demonstrated symptomatic improvement with formation of granulation tissue, resolution of rest pain, or both. The technical success rate was 100%.
At six months, 86% of patients (6 of 7) had avoided major amputation, and at 12 months 71% of patients (5 of 7) had done so. Complete wound healing was achieved in 57% of patients (4 of 7) at six months and in 71% of patients (5 of 7) at 12 months. The median healing time was 4.6 months.
Perfusion rose dramatically in the LimFlow patients, from 8mmHg pre-procedure to 59mmHg (p=0.080) at the time of healing.
The authors commented that, “The immediate angiographic appearance was dramatic. One patient who had prior lumbar sympathectomy and was on high doses of opioids for chronic pain had a dramatic resolution of her pain within 48 hours and was opioid free.”
There were two instances of myocardial infarction within 30 days, each with minor clinical consequences. Three patients died of causes unrelated to the procedure or device at six, seven, and eight months, respectively.
“It is our mission to reduce the incidence of amputation, resolve pain and promote wound healing in a previously hopeless patient population and we are very encouraged by the early promising results of the LimFlow System,” said LimFlow chief executive officer Dan Rose. “The high technical success rate also demonstrates that our novel concept of percutaneous and minimally-invasive bypass below the knee is an achievable and reproducible technique. We look forward to the results from our US feasibility study, which is currently enrolling, and our international post-market, multicentre study outside of the US to validate these early findings.”
The LimFlow System is designed to restore perfusion to the ischemic foot, which may relieve rest pain, promote chronic wound healing, reduce major amputations and restore mobility for patients when used as part of a multi-disciplinary team approach. It uses proprietary ultrasound-guided catheters and covered nitinol stents to uniquely bypass diseased arteries and divert blood flow into the tibial vein to vascularise the ischemic foot.
The LimFlow System received the CE mark in October 2016 and is currently available commercially in Europe. The LimFlow System is only available for investigational use in the USA, and has not been approved for sale in the USA, Canada, or Japan.