Deep vein thrombosis (DVT) affects 600,000 people a year. A significant proportion of DVT becomes chronic. Chronic DVT is an unfortunate affliction that can incredibly limit patients' activity levels, lifestyle, and can be a tremendous burden on society for the costs that it may incur.
In an interview with VEIN Magazine at the 2015 VEITHSymposium, venous expert, Dr. Mark Garcia shares his unique insights into DVT, his part in designing a treatment algorithm and the ACCESS PTS study--a multi-center trial designed to evaluate the efficacy and safety of ultrasound accelerated thrombolysis.
Q&A with Mark Garcia, MD
VEIN Magazine: Tell me what's being done right now in the space to help improve the quality of life of DVT
Dr. Mark Garcia: What we've been able to do is develop a multi-center study that looks at aggressive management or treatment for patients that are suffering from chronic DVT. This population can have a constellation of problems from pain and swelling all the way to venous ulceration that can be very difficult to manage and very painful. What we were able to find early on in evaluating and treating these patients is that we've been able to develop a method that in our single center registry was showing a significant improvement in the quality of life, and in many, resolution of post thrombotic syndrome all together.
This led to support from EKOS and BTG, to develop a multi-center study that allows us to evaluate these patients, use the treatment algorithm that we designed, and follow these patients with objective measures to see how they do and whether or not there has been a significant improvement in their quality of life, and in the ability to restore flow in these previously and chronically occluded venous segments.
VM: How does the EKOS technology work? We hear about low dose TPA. What is the value of the ultrasound, and how does that benefit the chronic DVT patient?
MG: There is a lot of debate currently as to what this may be doing in the chronic venous world. The real challenge is crossing the chronically occluded venous segments. Once you're able to cross using standard catheter techniques, what we do is create working space by dilating the occluded venous segments to an expected size of the normal vein. By doing that, we create a channel that we then place the ecosystem in, which I will describe in a second.
During that initial dilatation, often times you will get an acute thrombosis. The theory behind what we proposed was that the TPA itself is treating the acute clot that's being formed by us being and working in this venous segment.
What EKOS brings to the table is this ultrasound enhanced technology where ultrasound waves and transducers within the catheter system allow for deeper penetration of the TPA medicine into the clot. I have found an enhanced ability to soften some of this chronic fibrin stranding and scarring that's in the vein. For example, I've seen over and over again the inability to dilate segments with high pressure balloons because of a very tight stricture that we're unable to completely stretch or break. After the EKOS ultrasound waves have been in there, usually over night, when the patients return for the follow up, that stricture is very easy to break and to open the venous segment and restore the flow through there.
There is some, I think, scientific evidence that needs to be worked out. But clinically what I'm seeing in our cases is that there is an improvement in being able to stretch that vein and restore flow. I think it's because of the ultrasound waves that are working through there.
VM: How many centers are currently enrolling patients in the United States?
MG: We have thirty centers in the study. Currently, we have 72 patients enrolled as of this week, with 41 having been treated.
VM: Many people are really unaware about DVT in general. What about public awareness as it relates to chronic DVT? Are hospitals putting out protocols relative to how to treat DTV? Are doctors in their practices giving the education to the patients? What are you seeing currently happening or not happening public wise?
MG: Unfortunately, there has been very little work or education around chronic DVT across the country and across the world. It's really been driven by a small group of interventionalists and vascular specialists that may see these patients.
Often times, the awareness is found by the patient themselves on the internet looking for some help. The sad part of this is, in this day and age, worldwide, and certainly within the US, patients are often told, "There's nothing that can be done, you have to learn to live with your symptoms. Wear your compression dockings, maybe you get in a coagulation to help thin the blood." In general, there is not anything being offered. The vast majority of patients I see who fly from across the country and even from other parts of the world have been told this and have been suffering for years, until they are very excited to hear that some work has been done.
I can personally tell you, having treated hundreds of patients with chronic DVT, that invariably you see a lot of happy, smiling faces, incredible thanks, because you have changed their life by improving their quality, which we've been able to show objectively by measuring not only the leg itself, measuring the circumference of leg and showing significant reduction and normalization of the size of the leg, but also by using Villalta scoring which is a chronic Venous scoring measure that uses both clinical signs and symptoms of the patient to give a score. We've seen a tremendous amount in our registry that demonstrates the benefit of being able to intervene on these patients, and showing their improvement and their quality of life.