Stroke specialists at Plaza Medical Center in Fort Worth are using a revolutionary new mechanical device to remove blood clots from the brains of stroke victims. Physicians say the new Trevo XP ProVue Clot Retriever plucks out clots that are blocking blood vessels and restores blood flow to the brain more quickly, safely and efficiently than ever.
“The idea is to pull out the clot as quickly as possible in order to salvage as much brain tissue as we can,” said Dr. Ryan Gianatasio, an endovascular neurologist who specializes in acute stroke therapy at Plaza. The new “stentrievers” start restoring some blood flow the second they touch a clot – even before they are used to encapsulate and pull it out, Gianatasio said. “The Trevo XP is the newest generation of these ‘stentrievers,’” Gianatasio said. “It has the advantage of full-length visibility for precise positioning of the stent within the clot and a larger surface area to retrieve more of the clot on first pass. “It is also very smooth so you can go back in and out a number of times, if necessary,” he said.
The Trevo XP is manufactured by Stryker Corp., a medical technology company based in Kalamazoo, Mich. Intravenous drug treatment with tPA (tissue plasminogen activator), known as the “clot-buster drug,” is still the treatment of choice for most strokes caused by a blood clot, but in some cases, especially when a large clot is involved and time is running out, interventional neurologists turn to mechanical removal for back-up, Gianatasio said. Ischemic strokes – those caused by blood clots – account for about 87 percent of all strokes. Hemorrhagic strokes, which make up the rest, are initiated by burst blood vessels that cause bleeding in the brain. Both kinds of stroke destroy brain tissue by cutting off vital supplies of blood and oxygen. Over about the last 10 years, when clot buster drugs fail, physicians have turned to mechanical removal of the clot using various devices; those have evolved from a corkscrew-like device to pull out clots to various suction devices and, for the last couple of years, to various types of strentrievers.
The success rate for reopening the flow of blood to the brain has increased from about 40 percent to more than 90 percent, Gianatasio said. “TPA is still recommended if the patient is a candidate for an IV clot buster, but sometimes it can cause too much bleeding or take too long to dissolve a large clot,” Gianatasio said. If the drug is not working fast enough to prevent extensive brain damage, doctors consider whether mechanical retrieval is a viable backup. TPA therapy needs to start within about three to four hours of stroke symptoms, whereas the window of opportunity for mechanical clot removal is up to about eight hours, Gianatasio said.
“Immediate medical attention is required for any stroke – the sooner the better, before too much brain tissue is damaged,” he said. “We get a lot of helicopter transfers from small outlying areas as far away as Navarro, Abilene, Granbury, Glen Rose … where doctors have already done an MRI and started tPA. We evaluate the patient to determine if the benefits of mechanical clot removal outweigh the risks. “We just want people to know how important it is to get to the closest hospital offering primary stroke treatment, immediately. The time to call 911 is now – just as soon as symptoms suggest a stroke,” Gianatasio said.
Possible stoke symptoms include sudden numbness or weakness in the face, arm or leg, confusion (difficulty speaking or understanding speech), difficulty seeing out of one or both eyes, difficulty walking (dizziness, loss of balance) and severe headache. Plaza is one of 11 HCA hospitals that are part of the Texas Stroke Institute. It was the first hospital in North Texas and only the fifth in Texas to be certified as a comprehensive stroke center last summer. There are still only nine in the state, according to the Texas Department of State Health Services. “By being a comprehensive stroke center, Plaza has thoroughly demonstrated the greatest level of commitment to the care of our patients with complex stroke conditions,” said Clay Franklin, Plaza’s chief executive officer. “It proves we are providing the highest quality stroke care and significantly improving outcomes.”