Pioneering Non-Invasive Vascular Technologies Since 1984
Header:

Recent Research in IPC for Lower Limb Ischemia

artassist to treat lower limb ischemia

Lower limb ischemia caused by Peripheral Arterial Disease is a hot topic in medicine. Intermittent pneumatic compression therapy is being used to treat patients with ischemic limbs where conventional treatments (namely surgery) fail or cannot be used.

If you are interested in learning more about arterial pneumatic compression pump therapy to treat ischemic ulcers, ACI Medical encourages you to explore the growing research surrounding the ArtAssist® device.

The latest research comes from a presentation at the Society of Vascular Surgery Annual Meeting in June 2015. Excerpt from abstract:

Enhancing Neovascularization in Chronic Limb-Threatening Ischemia

Objectives: The shear stress stimulus needed to switch on arteriogenesis, attenuated in chronic limb-threatening ischemia (CLI), can be restored with intermittent pneumatic compression (IPC). IPC also increases inflow of
oxygenated nutritive blood, clears waste products of metabolism, and enhances the traffic of elements needed for neovascularization (NV). The circulating progenitor cell (CPC) population is also depressed in CLI. We hypothesize that NV will be promoted by IPC and CPC mobilization.

Continue reading…

Additional research begins to explore the effect of leg IPC on nitric oxide (NO) levels in the arm. Excerpt from abstract:

The effect of intermittent pneumatic compression of legs on the levels of nitric oxide related species in blood and on arterial function in the arm

Background: Intermittent pneumatic compression (IPC) of legs exerts beneficial local vascular effects, possibly through local release of nitric oxide (NO). However, studies demonstrating systemic transport of nitrogen oxide species and release of NO prompt the question of whether IPC could also exert nonlocal effects. We tested whether IPC (1) affects systemic levels of nitrite, S-nitrosothiols and red blood cell (RBC) NO, and (2) exerts vasoactive effects in the brachial artery (BA), although this hypothesis-generating pilot study did not investigate cause and effect relationship between (1) and (2).

Continue reading…

Additional studies surrounding the treatment of lower limb ischemia with IPC can be found on the Clinical Studies page under the Limb Salvage & CLI heading.

Contact ACI Medical to discuss all aspects of arterial IPC treatment, from ongoing research to how patients can easily obtain the ArtAssist® device for home use:

Toll Free (888) 453-4356 or info@acimedical.com

artassist to treat lower limb ischemia

Share Button

Compressing the foot and why it’s so important

Why calf-only arterial pumps are missing out

ArtAssist device compression sequence

ArtAssist®…The Arterial Assist Device® Compression Sequence

Calf-only arterial pumps are missing a key component because foot compression is essential to improving circulation in the skin of the foot. Good circulation is vital to the successful healing wounds and ulcers. ACI Medical’s ArtAssist® device went through numerous clinical trials in order to optimize compression therapy for treating peripheral arterial disease of the legs and feet.

Researchers and engineers optimizing the ArtAssist® device not only discovered the importance of compressing the foot in addition to the calf, but they also designed this arterial pump technology to imitate the physiological act of walking as closely as possible.

A bit of background

An early study to determine the physiological effects of  intermittent pneumatic compression therapy focused compression on the calf, foot, and both simultaneously.

Although significant increase in arterial blood flow was recorded for individual compression areas, the simultaneous combination yielded disappointing results because blood was not flowing back to the heart as anticipated.

After the conclusion was drawn that simultaneous compression did not produce the desired augmented blood flow for all tissues below the knee, researchers realized that the answer lay in a time delay. Strong, encompassing foot and ankle compression that boosts foot skin perfusion would come first, followed then by calf compression to amplify popliteal flow.

That magical formulation

In essence, foot/ankle compression + calf compression with time delay = successful emptying of venous blood, resulting in improved circulation.

The optimization study led by K. T. Delis, et. al. determined that this foot, ankle and calf compression sequence, applying 120-140 mmHg at a frequency of 3-4 impulses per minute, “provided the optimum intermittent pneumatic stimulus.”

The next logical step was a prospective randomized controlled trial to solidify the efficacy claims.

And the rest is history…

One example of such a trial studied not only the effects of the previously mentioned IPC method, but also the long-term effects on treated claudicants. The results indicated that treated claudicants still retained their ABI’s and walking benefits one year after the end of IPC application.

Following the numerous physiological and optimization studies for the ArtAssist® device, research facilities continued to explore the possibilities of arteriogenesis, therapy for patients with intermittent claudication, and limb salvage.

The ArtAssist® device is currently the only IPC device with this thorough progression of clinical studies and randomized controlled trials to support its efficacy.

References

  1. Improving Popliteal Artery Flow with Intermittent Pneumatic Foot and Calf Compression.” Delis, K.; Labropoulos, N.; Nicolaides, A.N.; Stansby, G.; and Lumley, J. Irvine Laboratory for Cardiovascular Investigation and Research, Academic Surgical Unit, Imperial College School of Medicine, St. Mary’s Hospital, London, UK.
  2. Enhancing Venous Outflow in the Lower Limb with Intermittent Pneumatic Compression. A Comparative Haemodynamic Analysis on the Effect of Foot vs. Calf vs. Foot and Calf Compression.” Delis, K.T.; Slimani, G.; Hafez, H.M. and Nicolaides, A.N. Irvine Lab for Cardiovascular Investigation and Research, Academic Vascular Unit, Imperial College School of Medicine, St. Mary’s Hospital, London UK. Eur J Vasc Endovasc Surg 19, 250-260; 2000
  3. The Acute Effects of Intermittent Pneumatic Foot and Calf Compression on Popliteal Artery Hemodynamics: A Comparative Study.” Delis, K.T.; Nicolaides, A.N.; Labropoulos, N.; and Stansby, G. Imperial College School of Medicine, St. Mary’s Hospital, London, UK. J Vasc Surg, 2000; 32: 284-92
  4. Intermittent Calf and Foot Compression Increases Lower Extremity Blood Flow.” Eze, A.R.; Comerota, A.J.; Cisek, P.L.; Holland, B.S.; Kerr, R.P.; Veeramasuneni, R.; Comerota, A.J. Jr. Presented at the 24th Annual meeting of the Society for Clinical Vascular Surgery; March 1996. Am J Surg 1996; 172:130-135
  5. Optimum Intermittent Pneumatic Compression Stimulus for Lower-limb Venous Emptying.” Delis, K.T.; Azizi, A.A.; Stevens, R.J.G.; Wolfe, J.H.N.; Nicolaides, A.N. Eur J Vasc Endovasc Surg 19, 261-269 (2000).
  6. Improvement in Walking Ability, Ankle Pressure Indices and Quality of Life in Vascular Claudication Using Intermittent Pneumatic Foot and Calf Compression; A Prospective Randomized Controlled Trial with 1 Year Follow-up.” Delis, K.T.; Nicolaides, A.N.; Cheshire, N.J.W.; and Wolfe, J.H.N. Academic Vascular Surgery, St. Mary’s Hospital, London, UK. Presented at the Vascular Surgical Society of Great Britain & Ireland, Nov. 2000, London Arena.
Share Button

Challenge conventions. You may end up saving a limb!

Previously, I posted a whole article about how it’s actually not dangerous to use compression therapy on an ischemic limb. However, that’s not the only misconception that we’ve cleared up at ACI Medical. This article exposes a couple more myths that have been known to float around, and how we’ve found evidence to set the record straight.

Even after some experts dismissed the idea of intermittent pneumatic compression (IPC) as a viable treatment for patients with PAD, the creators and developers of the ArtAssist® device put their theories to the test nonetheless.

Pioneered and developed with vascular surgeons, the ArtAssist® device continues to be the leader in IPC therapy for non-surgical PAD patients with varying levels of severity.

ArtAssist® IPC therapy should not be overlooked or dismissed without having considered the clinical evidence:

in fact, it has both saved limbs and improved patient quality of life.

MYTH: Critically ischemic limbs are maximally vasodilated.

False.

In fact, the ArtAssist® device’s first physiological clinical trial disproves this myth. Even without having been optimized to the extent it is now, the prototype yielded results that suggested transient vasodilation.

Later, in 2005, a study conducted by Professor Labropoulos of SUNY not only confirms the earlier findings, but also suggests that increasing the arteriovenous pressure gradient with foot & calf IPC therapy contributes greatly to significantly increased blood flow in the subjects’ popliteal, gastrocnemial and collateral arteries. Skin blood flow also improved significantly in their findings.

MYTH: The ArtAssist® device is the same as any other arterial pump with similar function.

False.

We encourage you to ask yourself these two important questions when considering other devices which claim to perform as efficaciously as the ArtAssist® device:

1. Is it optimized for arterial disease? And

2. Is there clinical evidence and support for this specific device?

Only the ArtAssist® device satisfies each of these questions with its thorough progression of clinical studies: this device alone has been adjusted and optimized from its initial prototype over the past two decades to effectively treat even the most severe cases of PAD.

  • Physiological
  • Optimization
  • Intermittent Claudication
  • Limb Salvage
  • Critical Limb Ischemia (CLI)
  • Arteriogenesis (Collateralization)

Currently, studies are being conducted to explore the ArtAssist® device’s efficacy for adjunct therapies, such as stem cell treatment and gene expression.

The Bottom Line.

Your patient’s non-reconstructable limb will not wait for hearsay on this form of therapy.

We are here to let you know that therapy with the ArtAssist® device gives patients a dependable option that continues to help non-surgical limbs across the country.

Make the decision that could save your patient from amputation.

References

Augmentation of blood flow in limbs with occlusive arterial disease by intermittent calf compression. Van Bemmelen, P.S.; Mattos, M.A.; Faught, W.E.; Mansour, M.A.; Barkmeier, L.D.; Hodgson, K.J.; Ramsey, D.E.; and Sumner, D.S. Springfield, IL. Journal of Vascular Surgery 1994; 19:1052-8.

Hemodynamic effects of intermittent pneumatic compression in patients with critical limb ischemia. Labropoulos, N.; Leon, L.R.; Bhatti, A.; Melton, S.; Kang, S.S.; Mansour, A.M.; and Borge, M. The Department of Surgery, Loyola University Medical Center, Maywood, IL. Journal of Vascular Surgery, October 2005; Volume 42, Number 4: 710-716

Share Button

Compressing Ischemic Limbs and Why It’s Beneficial

To download a printable PDF of this article, click here:  Compressing Ischemic Limbs and Why It’s Beneficial

The Misconception

Is it true that arterial occlusive disease is an absolute contraindication for intermittent pneumatic compression (IPC)?

The Answer

Not at all!

Unfortunately, many medical professionals are under the impression that applying even a small external pressure to an ischemic limb with reduced distal arterial pressures may serve to reduce or completely stop the already-compromised blood flow. This article presents strong evidence that, contrary to popular belief, IPC can bring life-changing benefits to those who cannot undergo revascularization.

History

Part of the reason this dogma exists is because, for many who consider it, applying IPC to ischemic limbs seems counterintuitive and likely dangerous. Also contributing to this myth are the literature reviews written by investigators as far back as 1934 who showed a poor understanding of the physiological mechanisms. Though these measured acute effects of compression on increased blood flow in ischemic limbs and relief of symptoms, the assessments made about IPC therapy were muddled due to the use of a great variety of compression schemes and devices. This lack of clarity resulted in literature that only served to feed misgivings about IPC as a treatment modality.

Physiological & Optimization Studies | ACI Medicalarteriovenous pressure gradient

To demystify the true value of IPC, our goal was to determine the physiological mechanisms of action, to optimize IPC design for maximal acute effect, and to determine if there is a clinical benefit to patients with lower extremity ischemic disease.

We started with physiological studies1 with compression applied to the dependent limb, which showed these acute mechanisms:

  • Increased arterial-venous pressure gradient
  • Reduced peripheral resistance
  • Abolition of the veno-arteriolar reflex

Further studies2 concerned optimization:

  • Pressure:  at least 120 mmHg
    This high pressure is required to empty the veins in the dependent limb, which temporarily reduces venous pressure to near zero and increases the arterial-to-venous pressure gradient and therefore, flow. Reducing venous pressure also serves to temporarily abolish the veno-arteriolar reflex, which allows for arteriolar dilation.
  • Timing:  3 second pulses followed by 17 seconds of low pressure
    An essential requirement for an arterial pump is the ability to quickly reach inflation and deflation pressures with rise times of 0.25 to 0.30 seconds and fall times under 0.5 seconds.  This rapid squeeze and release creates blood velocities that apply shear stress to the endothelium which releases nitric oxide and further supports the large acute vasodilatory effect in the arterioles.
  • Compressed tissues:  foot, ankle and calf regions
    In order to maximize blood flow through the major arteries and to the toes where ischemic disease often presents, we found that a circumferential foot bladder including the ankle should be compressed first, followed one second later by compression of the calf with a relatively large asymmetrical bladder.

Randomized Controlled Trials | ACI Medical

Intermittent Claudication

Once the arterial IPC device was optimized, three randomized controlled trials3 were performed on patients with intermittent claudication. Not only did these trials yield significantly increased walking distances of two to three times, but also sustained “permanent” improvements begged the question, “What long term mechanisms might be at work?”

Limb Salvage due to Arteriogenesis

Further studies4 showed that arteriogenesis (the opening of collaterals) was responsible for improved ABI’s, PVR’s, toe pressures and popliteal flow. A recently published study from 20105 reported a 94% limb salvage rate at 3.5 years in patients who were unable to undergo revascularization procedures.

Arterial Assist Device, NOT Lymphedema Pump

ArtAssist Arterial Assist Device

ArtAssist®…The Arterial Assist Device®

Today, it is widely-known that IPC devices are designed for prophylaxis against deep vein thrombosis (DVT) and for treatment of lymphedema. However, the understanding behind these devices does not coincide with our exploration of IPC to treat severe forms of arterial disease. Lymphedema and DVT devices do not apply enough pressure to the dependent limb to adequately empty the veins, nor do they apply and release pressure rapidly enough to stimulate release of nitric oxide (NO). While such devices will not significantly improve blood flow in the ischemic limb, it is difficult to say whether they would be harmful without further study.

References in this Publication

  1. Effect of intermittent pneumatic foot compression on popliteal artery haemodynamics. Delis, K.T.; Labropoulos, N.; Nicolaides, A.N.; Glenville, B.; and Stansby, G. Imperial College School of Medicine, Academic Vascular Surgery, St. Mary’s Hospital, London, UK. Eur J Vasc Surg, p. 270-277, vol. 19, no. 3, March 2000.
  2. Optimum intermittent pneumatic compression stimulus for lower-limb venous emptying. Delis, K.T.; Azizi, A.A.; Stevens, R.J.G.; Wolfe, J.H.N. and Nicolaides, A.N. Irvine Lab for Cardiovascular Investigation and Research Academic Vascular Surgery, Imperial College School of Medicine, St. Mary’s Hospital, London, UK. Eur J Vasc Endovasc Surg 19, 261-269 (2000).
  3. Improvement in walking ability, ankle pressure indices and quality of life in vascular claudication using intermittent pneumatic foot and calf compression:  a randomized controlled trial. Delis, K.T.; Nicolaides, A.N.; Cheshire, N.J.W.; Wolfe, J.H.N. St. Mary’s Hospital, London, UK. British Journal of Surgery December 2002; Volume 88, Issue 4:605-606.
  4. Angiographic improvement after rapid intermittent compression treatment (ArtAssist®) for small vessel obstruction. Van Bemmelen, P.; Char, D.; Giron, F.; and Ricotta, J.J. Dept. of Surgery, Div. of Vascular Surgery, State University of New York at Stony Brook, NY. Ann Vasc Surg 2003; 17:224-228.
  5. Sequential compression biomechanical device in patients with critical limb ischemia and nonreconstructable peripheral vascular disease. Sultan, S.; Hamada, N.; Soylu, E.; Fahy, A.; Hynes, N. and Tawfick, W. Department of Vascular and Endovascular Surgery, University College Hospital, Galway, Journal of Vascular Surgery 2011; 54:440-447.
Share Button

Arterial Pump Choosing Guide

At ACI Medical, we know that there are more home-use intermittent pneumatic compression devices (in other words, arterialArtAssist device patient pumps) similar to the ArtAssist® device out on the market, but here is the best we can say for them:  they may work, they may not. This is because the ArtAssist® device is the only device of its kind to have been optimized to treat arterial disease through clinical trials at multiple independent centers. In other words, research done on the ArtAssist® device itself supports our claims about its capabilities.

Through numerous clinical trials, ACI Medical’s researchers have determined what the ArtAssist® device system needs to increase blood flow to the lower extremities as much as it does. If you’re thinking about getting an arterial pump to treat PAD (peripheral arterial disease), here’s what you should look for and why:

Cuff Specifications

Bladder Locations

artassist arterial pump cuff

It is important to have air bladders compressing the foot, ankle and calf regions because this promotes more blood flow to the skin.

When you are considering an arterial pump, also take a look at the size of the air bladders. The larger they are, the more tissue they’re

going to reach. The more tissue they reach, the more circulation.

Inflation and Deflation Rates

Research shows that quick inflation and deflation rates of the air bladders (less than half a second) put what’s called shear stress on your blood cells. Shear stress is good, because when your endothelial cells experience it, they release a muscle relaxant (or a vasodilator called nitric oxide) that helps open the small collateral arteries that are capable of naturally bypassing the blocked artery. It takes around 3 months, and the improvements are long-term. We call this process arteriogenesis or collateralization

Now, this process I described does take a lot longer (typically between 3-6 months) than an open bypass operation, but for people who aren’t good candidates for surgery, it may be worth it to look into arterial pump treatment.

Cuff Pressure

ArtAssist compression sequence 120mmhg

Rapid sequential compression

Now you know that cuffs should have large bladders at the foot, ankle and calf and that they should inflate and deflate quickly. But what kind of pressure should the air bladders reach?

The answer that researchers found was 120 millimeters of Mercury (mmHg), which is about the pressure of a very firm handshake. Below this pressure, blood flow was not as high. Above 120 mmHg was unnecessary and, furthermore, uncomfortable for patients.

Clinical Research

You know I’ve been hinting at it, and I can’t stress it enough:  make sure the device you invest in has clinical research supporting its claims. Research done at respected institutions is usually a very good sign for an arterial pump you’re considering. Also, if you can find a study that’s been done on patients with your diagnosis, even better!

UPDATE:

Being optimized to treat arterial disease is of the utmost importance. Research at the Mayo Clinic suggested that if a pump is NOT optimized for arterial disease, using it could actually DECREASE blood flow – a waste of your precious time and money! For example, some arterial pumps on the market have been modified from DVT prophylaxes and do not have much published clinical support.

So, like any decision you make concerning your health, I encourage you to do a bit of research and ask yourself:  did the makers of this arterial pump design it specifically to treat arterial disease? Straight answers are the best.

Customer Service

Patient Compliance

Basically, make sure you can commit to using your arterial pump for however often your physician has prescribed it. As an example, we’ve seen the ArtAssist® device do amazing things for people – and it’s because they got into the habit of using it every day.

Patient Accommodation

Are you dealing with a special condition? Have you already had a below-knee amputation or are you unable to tolerate foot compression? Is your situation unique? It’s helpful to know that your arterial pump provider is knowledgeable enough to listen to what you’re going through and find a solution so you can get the therapy you need.

Obtaining Your Therapy

Just consider:  how many numbers do you have to call to get an arterial pump? Do you have to go to a clinic every day or can you conveniently keep it at home? Find an arterial pump provider that makes it as easy as possible.

The Arterial Pump That Comes Out On Top

artassist device arterial pump technologyThere’s only one number to call if you want to order, prescribe, or just get more information about the ArtAssist® device:  (888) 4 LEG FLO (888-453-4356). Alternatively, you can email info@acimedical.com any time of the day.

For our references, see our Clinical Studies page.

To read documented success stories of ArtAssist® device patients, take a look through the Case Reports page.

Share Button

ArtAssist® Arterial Pump Technology

Home-use compression device for patients with

Peripheral Arterial Disease

The ArtAssist Arterial Pump Device

The reason we named it “ArtAssist®” is because this specially engineered pump and cuff system gives patients’ limbs exactly what they need to heal:  more arterial blood flow. The ideal candidate for this uniquely optimized, completely non-invasive therapy suffers from severe symptoms of peripheral arterial disease – arterial occlusive disease of the upper and lower extremities. In a mere matter of weeks, patients see dramatic improvements, such as lessening of pain and wounds that finally begin to heal as a result of the improved circulation that ArtAssist®…the Arterial Assist Device® promotes. In as little as 90 days, daily usage of the ArtAssist® device can result in permanent improvements to the treated limb’s arterial circulation.

Share Button

Patients should be proactive and aware about their PAD

Today, a man came in to our office to talk to us about renting an ArtAssist® device. He has had peripheral arterial disease for years and previously rented our device a few years back.

He came in because, as he said, wound care in other places wasn’t very well agreed upon, and he saw hair regrowth on his feet when he rented and used our device a few years back. His other options were too costly for him, including hyperbaric oxygen therapy (I found a link – click here – to get a ballpark idea of how much each HBO session is).

Today, we wish that more patients were like him because he has lately noticed hair loss on his feet again and is taking steps to prevent his PAD from advancing.

Visit the ArtAssist® device website to see if you or someone you know can benefit from therapy. You can also poke around on the clinical studies page to read what researchers have to say about the device (in a nutshell, it’s efficacious and cost-effective, but don’t feel like you have to take my word for it).

Also, check out all the posts I have on amputation – it would take quite a while to post them all here, but I do have a lot of articles on cost comparison and quality of life.

Share Button
Footer: