Up to 400,000 people in the U.S. have deep vein thrombosis (DVT), which untreated, can result in a blood clot breaking off, traveling to the lungs, causing a pulmonary embolism and, sometimes, death.

The standard of care has been anticoagulation therapy, which comes with an array of complications. New data from a study of patients who received treatment with Bacchus Vascular’s (Santa Clara, California) Trellis Peripheral Infusion System shows the treatment breaks up a blood clot in most patients much quicker than using a drug alone, according to an analysis presented at the 33rd Annual Scientific Meeting of the Society of Interventional Radiology this week.

More than 700 patients with DVT were treated with Trellis, which received FDA 510(k) clearance in 2005 (Medical Device Daily, March 30, 2005). It combines the use of clot-busting drugs with a drug dispersion device, giving interventional radiologists physical assistance to break up the clot faster.

“What’s interesting about these latest results is it’s much larger than most other series of data,” Dennis Rosenberg, VP marketing for Bacchus told Medical Device Daily. “Usually there are just 50 to 100 patients, but we’ve been diligently collecting data. We think we have the largest reported database on acute DVT patients.”

“Current medical therapies do nothing to treat the clot that’s already there,” Rosenberg said. “People have always had to live with it and it leaves them with post-thrombotic syndrome — painful, swollen, red legs — and that that impacts their quality of lives.

Gerard O’Sullivan, MD, an interventional radiologist from University Hospital (Galway, Ireland), reported the latest outcomes from the manufacturer’s registry of clinical results of the Trellis catheter at over 360 hospitals.In a total of 827 limbs treated in 771 patients, Grade II and III lysis with restoration of patency in patients with acute clot was achieved in 97% of cases. The vast majority of cases (> 80%) were completed in less than two hours in the single-setting of the interventional suite, and the usage of the Trellis catheter itself was typically around 20 minutes. Although required with CDT procedures, no follow-up monitoring in a costly critical care unit was typically needed with the Trellis catheter treatment.

The Trellis is positioned at the site of the clot and a balloon is inflated on both sides of the clot to prevent pieces of the clot from traveling to other parts of the body and to isolate the treatment zone, so that there is less chance the infused drug will cause bleeding. Then a dispersion wire is fed through the catheter of the system. The wire begins to rotate, mixing the clot-busting drug within the clot; the clot pieces are aspirated into the catheter and removed from the body.

This technique restores blood flow more quickly and safely than current catheter-directed thrombolysis (CDT) techniques, according to the company. It provides an adjunct to the standard therapy of anti-coagulation alone, which is intended to prevent future clots but does not break up the existing clot.

There were no reported bleeding complications from the Trellis procedure in acute follow-up and compared to CDT the dosage of thrombolytic drugs such as tPA are appreciably reduced with use of the Trellis device.

“The single biggest change in treating DVT patients with the Trellis catheter is our ability to get the clot out and have the patients able to walk away immediately after the procedure,” said O’Sullivan. “Literally, the patient comes into the procedure with difficulty or cannot walk and I can now walk them out of the procedure room at the end of the treatment. These patients are typically back to work in two to three days vs. the six to eight weeks with anticoagulation-only treatment.”

Trellis is designed for patients with proximal DVT, a type of the condition in which clots form from the mid-thigh and up the leg. “A large number form lower in the leg and they don’t have the same consequence for patient as the larger vessels,” Rosenberg said. “Those that form closer to the heart do have bigger consequences.”

Trellis is Bacchus’ only product. “We’re still in the formative stages. In the couple of years that it’s been FDA approved, we’ve sold several thousand, but we’ve just scratched the surface when you look at the magnitude of the condition,” Rosenberg said.

DVT has been recognized by the National Quality Forum and the Joint Commission as a major preventable cause of death in hospitals. Rosenberg said that there’s a new Joint Commission initiative telling hospitals that they need a quality standard and programs to prevent and treat DVT.

“So there’s this confluence of things where devices like ours are coming to the fore,” Rosenberg said. “Over the next year, we’ll see a lot more visibility of this product. DVT has been an overlooked area.”