Mechanical Thrombectomy

If you or a loved one should ever have a stroke caused by a blood clot (ischemic stroke), it’s important to know that Norwalk and Danbury hospitals are the first facilities in Fairfield County to offer a breakthrough treatment called mechanical thrombectomy.

With mechanical thrombectomy—also called endovascular therapy—a special device is threaded through the blood vessels to the site of a stroke-causing blood clot in the brain. The device grabs the clot and removes it, restoring blood flow to the brain—and dramatically improving outcomes.

And now, a major clinical study shows that certain patients can benefit from this minimally invasive procedure up to 24 hours after the onset of stroke symptoms. Previously, the window for this treatment was only 6 hours.

As a result, more ischemic stroke patients can now be treated successfully. And this procedure is rapidly becoming the gold standard in ischemic stroke treatment due to its safety, efficacy, expanded treatment window, and excellent patient outcomes.

An ischemic stroke occurs when an artery carrying blood to the brain is blocked by a blood clot. There are two types of ischemic strokes:

  • Thrombotic strokes are caused by a blood clot (thrombus) in an artery going to the brain, blocking blood flow. Blood clots usually form in arteries damaged by plaque, a fatty material that can build up inside blood vessels.
  • Embolic strokes are caused by a traveling clot (embolus) that forms elsewhere (usually in the heart or neck arteries); it’s carried in the bloodstream and blocks a smaller blood vessel in or leading to the brain. 

Within minutes of the brain being deprived of oxygen-rich blood, brain cells start to die. Left untreated, an ischemic stroke can cause serious disability including paralysis, difficulty talking or swallowing, and memory loss. It can also cause death.

That’s why a stroke is a true medical emergency, and fast treatment is essential to minimize brain damage and possible complications.

When a stroke patient arrives for treatment, the clot-busting medication called tPA is usually delivered directly to the site of the clot. After administering tPA, our stroke specialists use advanced neuro-imaging to evaluate the patient’s brain.

If tPa alone doesn’t dissolve the clot and restore blood flow, and the patient is a good candidate for mechanical thrombectomy [LINK to “Who is a candidate for mechanical thrombectomy?” page], here’s what happens:

  • Using x-ray-guided imaging, a catheter (a long, thin flexible tube) is threaded into an artery in the groin (the femoral artery) and up through the neck, until it reaches the blood clot causing the stroke
  • A device called a stent retriever is inserted into the catheter to the site of the blood clot
  • The stent reaches past the clot, expands to stretch the walls of the artery so blood can flow, and retrieves the clot by snaring it and pulling it backwards, completely removing it from the body and restoring blood flow

Until recently, less than one in 10 patients suffering from an ischemic stroke received mechanical thrombectomy, due in part to lack of scientific evidence that treatment was effective beyond 6 hours of when stroke symptoms began.

As a result, many patients whose symptoms started when they were asleep, for example, or who didn’t get to the hospital fast enough, were disqualified from receiving mechanical thrombectomy.

Not any more.

The groundbreaking DAWN Trial, recently published in the New England Journal of Medicine, provides compelling evidence that stroke patients can be effectively treated six to 24 hours after they were last seen feeling well.

This greatly expanded treatment window means more patients can benefit from mechanical thrombectomy, significantly reducing the risk of stroke-related disability and death.

But remember: The best outcomes are still achieved when patients are treated as quickly as possible. So if you or a loved one shows signs of a stroke, call 9-1-1 right away.

Mechanical thrombectomy is performed in patients who have what’s called large-vessel occlusion. This means a blood clot is blocking (occluding) one of the large blood vessels—such as the carotid arteries or cerebral arteries—that supply oxygen-rich blood to the brain.

We also use advanced imaging to map which areas of the brain have an adequate blood supply. This enables us to see tissue that’s already damaged and tissue we can save by restoring blood flow. This gives us a realistic picture of how much we can help each patient by performing mechanical thrombectomy.

There are many reasons to choose Danbury and Norwalk hospitals for stroke care, including:

  • We are the only facilities in Fairfield County to offer mechanical thrombectomy, a minimally invasive procedure that’s fast becoming the gold standard for treating for ischemic stroke
  • Our hospitals are certified by The Joint Commission as Primary Stroke Centers, which means we have specially trained doctors, nurses and support staff available 24/7 for fast, accurate diagnosis and expert stroke treatment
Western Connecticut Health Network Neurosurgeon Joshua Marcus, MD, is nationally recognized for his expertise in endovascular stroke treatment. Learn more about Dr. Marcus.