Technology is advancing rapidly in the area of Mechanical Thrombectomy for large vessel occlusion strokes. It was not that long ago that we had no treatment at all for patients who experienced a stroke. The stroke would simply expand, and depending on the amount of tissue damaged and the particular areas of the brain involved, the patient would either die or be left with severe disabilities that required extensive and ongoing rehabilitation. Those patients might eventually resume normal activities, but more often than not, instead face their remaining years with some level of permanent disability.
In the mid-1990s, the introduction of tPA (tissue plasminogen activator), a “clot busting” medication, increased the chance of minimal or no disability at 90 days post-stroke by 30%. However, subsequent studies have shown that tPA is only effective in approximately 13% of Large Vessel Occlusion strokes. Compare that with a recent meta-analysis of Mechanical Thrombectomy trials, which showed that for every 100 patients treated with Mechanical Thrombectomy, 40 would be less disabled, and an additional 23 would achieve an independent outcome. These results support Mechanical Thrombectomy as the new/current gold standard for Large Vessel Occlusion strokes.
In a prior blog, we addressed the challenges still experienced across the country with a lack of enough Thrombectomy Capable stroke centers to meet the population need. Corazon strongly advocates the need for Primary Stroke Centers to evaluate the addition of this service based on the location of other Comprehensive/Thrombectomy-capable stroke center-mile radius.
While Corazon continues to work to increase the availability of thrombectomy services at certain hospitals with clear opportunity to increase access to care, the technology to improve the speed of treatment is also advancing. Artificial Intelligence (AI) is fast becoming a key tool in managing the rapid identification of large vessel occlusions as a means to significantly decrease the time from Computed Tomography Angiography (CTA) to Mechanical Thrombectomy. AI is often established in a Hub-and-Spoke pattern with the Comprehensive/Thrombectomy-Capable stroke center serving as the Hub, and the other hospitals in the surrounding area serving as the Spokes.
Compare the workflow with and without AI:
Without AI | With AI |
| Patient triaged outside the 3 to 4.5 hr window for tPA, but within the 24 hr thrombecotmy window. Patient is taken to radiology for CTA. | Patient triaged outside the 3 to 4.5 hr window for tPA, but within the 24 hr thrombectomy window. Patient is taken to radiology for CTA |
| Patient is returned to Emergency Room following the CTA to await the reading of the scan by a Radiologist. | During the CTA, AI identifies the Large Vessel Occlusion and sends alert to the Stroke Neurologist and the Neuro-Interventionalist at the Comprehensive/Thrombectomy-Capable Stroke center nearby. This can also trigger an alert to the ER MD and in-house Neurologist. |
| Radiologist reads the CTA. Depending on the facility’s required reading time, this may be as long as a two-hour wait. | Neuro-Interventionalist views images immediately and validates the large vessel occlusion, then notifies the Neuro-Interventional team of an incoming patient. Team prepares the Neuro-Interventional room. |
| Radiologist contacts the ER or Neurology provider with the results that indicate a large vessel occlusion. | Neuro-Interventionalist contacts the ED or Neurology provider at the non-thrombectomy (Spoke) facility to arrange transfer to the Thrombectomy Capable (Hub) facility. |
| The ER or Neurology provider contacts the Neuro-Interventionalist at the Comprehensive/Thrombectomy-Capable stroke center nearby to discuss the case. | Patient transferred directly to the Neuro-Interventional lab at the Thrombectomy-capable facility and undergoes procedure. |
| The Radiology Department sends images via computer system to the Neuro-Interventionalist for viewing. | |
| Neuro-Interventionalist validates the large vessel occlusion and re-contacts the non-thrombectomy hospital to arrange for patient transport to the Neuro-Interventional suite. | |
| Patient arrives in Neuro-Interventional suite and undergoes procedure. |
It is often stated that ‘Time is Brain’. In fact, 1.9 million brain cells die every minute during a stroke prior to the opening of the blocked vessel. As can be determined from this example, significant opportunity for improvement exists in the time from the patient’s arrival to the procedure when using AI. The addition of this technology can result in much lower brain cell death, which in turn means less resulting disability.
With the continued increase of stroke cases across the US, and the fact that program expansions to thrombectomy aren’t keeping pace to ensure patient access to this critical time-sensitive care, Corazon believes that all Primary Stroke Centers and other larger-hospitals with viable neuro programs should evaluate the market to determine opportunity for this service. Indeed, not all hospitals have the resources to become a busy “hub” for neuro intervention; however, all hospitals CAN and SHOULD consider the regional landscape of stroke care and how they can fit in. Whether a spoke for a partner hospital, or the hub in the absence of any other advanced program in the area, thrombectomy is no doubt where stroke care is headed for optimal result.
