For a long time, the medical community’s focus regarding the treatment of the condition was to uncover how to help patients manage their symptoms while reducing the progression of the disease altogether. In addition to taking preventative measures such as encouraging patients to maintain a healthier lifestyle, mitigating PAD progression and symptoms still remains the primary goal.
However, we’re still seeing very high rates of restenosis caused by the overgrowth of scar tissue from traditional stent placement. PAD lesions and blockages often cause severe pain and are typically followed by limited mobility and non-healing leg ulcers, which also often result in the need for amputation due to blood vessels that cannot be revascularized.
We have more than one million patients in the U.S. living with PAD-related limb loss, and the mortality rate for patients who experience lower-extremity amputation is high. Let’s pause here for a moment. That means that of those nearly 500,000 mothers, brothers, lovers, friends, neighbors who have lost a limb, many will die.
These high rates of blockages and amputations have necessitated the development and advancement of innovative tools and technologies to improve the long-term treatment and management of PAD symptoms and consequences. Here’s a look at some of those innovations and advancements:
Peripheral Stents
In December 2015, the FDA approved Biotronik’s Astron for iliac lesions. Astron is a self-expanding stent that has since been made available in several diameters (7-10 mm) and lengths (30-80 mm). Astron also has a 12-month patency rate of 89.8%, with a targeted lesion revascularization (TLR) rate of 1.4%. Biotronik’s innovative stent has had patients seeing an improvement in their ambulatory function and overall quality of life within a year of the stent’s implantation.
Biotronik is currently one of several MedTech companies with FDA approval for stent devices and research. Boston Scientific also received FDA approval for its Innova Self-Expanding Stent specifically designed for the superficial femoral artery and proximal popliteal artery (SFA, PPA). Boston Scientific’s Innova design has also paved the way for the Eluvia drug-eluting vascular stent (still in development) but already reflects a primary patency rate of over 95%.
There has been a longstanding need for a stent treatment that can handle the torque and pressures found in the legs and feet that won’t lead to in-stent restenosis and stent fracturing. These very issues are what led to the development of specialty stents that are self-expanding, flexible, and can handle the external pressures that the lower limbs endure.
Drug-Coated Balloons
Late into 2014 and during the spring of 2018, several FDA-approved drug-coated balloons (DCBs) hit the market.
The first two DCBs — the Lutonix created by C.R. Bard and the IN.PACT Admiral created by Medtronic — were both designed to treat SFA. Since peripheral stents have a typically high response rate, DCBs were seen as a way to treat vessel segments without the risks by delivering certain antiproliferative drugs directly to the site of the blockage.
The later DCB, known as Stellarex, was designed by the Spectranetics Corp. for the specific purpose of treating below the knee (BTK) disease. Using EnduraCoat technology, Spectranetics gave Stellarex a uniformly coated design to prevent drug loss in transit.
A Promising Technology
LimFlow, Inc. (a former client of TMG360 Media) has been a well-known pioneer in minimally-invasive CLTI treatment technology for some time now. The medtech company has been hard at work developing its Percutaneous Deep Vein Arterilization System, which is essentially a minimally invasive device with the ability to bypass blocked leg arteries to restore blood flow.
Ultimately, LimFlow’s innovative technology will help vascular surgeons and interventionalists conduct deep venous arterialization (DVA) as an alternative for patients with no other revascularization options. Rather than having to amputate, the technology may restore blood flow and critical oxygen supplies to the depleted tissues, promoting wound healing and, subsequently, improved quality of life. Two-year results from the PROMISE I trial showed that freedom from amputation was 77%, 85% of wounds were completely healed, and 92% of patients were either healed or healing.
The Future of PAD Treatment
The future is looking much brighter for PAD patients thanks to the help of these innovative treatments that focus on battling not just medical law and policy but also the disease itself. Having said that, the effectiveness of revascularization of patients with PAD is about more than just the procedures used.
The approach begins with achieving a better understanding of the populations at risk and how they vary in clinical presentation. In recent years, we’ve seen plenty of new tools, including wires, catheters, drug-eluting technology, biomimetic stents, and specialized balloons. The strategy and techniques used to employ these new tools vary by clinical presentation, lesion severity, and location. In addition to revascularization, the next step is medical therapy to reduce adverse outcomes, which requires a surveillance plan for each PAD patient that receives treatment via new medical technologies.
The medical community has come a long way in its innovations for medical device treatment technology and their associated antiproliferative drugs in treating PAD. Of course, there are still many challenges to overcome in regards to improving the efficacy of revascularization, including restenosis, calcification, microvascular disease, and silent embolization.
Ultimately, the goal is to move towards safer and more long-term solutions that offer an overall better quality of life. The medical technologies coming to market bring us to the cusp of achieving this goal, which will undoubtedly positively impact current practices and procedures — all in an effort to save lives.
The information provided here is not intended as medical advice, diagnosis or treatment. You should consult with a qualified healthcare provider for advice concerning your specific situation.
