By Bob Marshall, Chief Editor, Med Device Online
We’ve all seen or heard commercials from the American Stroke Association (ASA) encouraging people who suspect they might be having a stroke to call 9-1-1 right away, because “time lost is brain lost.” Stroke is the No. 5 cause of death in the United States, killing nearly 130,000 people a year — one in every 20 deaths, according to the ASA. But even if you survive a stroke, you are not even close to being out of the woods.
Some years ago Dr. Jeffrey L. Saver published Time is Brain - Quantified (a take-off of the proverb “time is money”). The article emphasized that human nerve tissue is rapidly lost as stroke progresses, and emergent evaluation and therapy are required. Through systematic literature reviews, as well as various assumptions and calculations, Saver connected degradation of the brain to time for patients experiencing a typical large vessel acute ischemic stroke. His article indicates that 120 million neurons, 830 billion synapses, and 714 km (447 miles) of myelinated fibers are lost each hour. In each minute, 1.9 million neurons are destroyed!
I was previously unaware of Dr. Saver’s article, and I had not even heard of the massive number of neurons lost each minute during a stroke until I spoke with Stacey Pugh, VP and GM of Medtronic’s Neurovascular business. I talked with Pugh regarding the recent FDA clearance of Medtronic’s Riptide aspiration system, but our conversation went so much further. In researching this column, I became intrigued with Pugh’s background and experience, as well as her pathway to a key leadership role within Medtronic neurovascular, which included 10 years of increasing responsibility in clinical operations, clinical affairs, and medical affairs leading up to her current role. Her understanding of the medical realities that shape the neurovascular market and her passion for better care for patients is palpable.
“When a patient comes in and is determined to have a large vessel occlusion, the existing data would show that, for each 30 minutes of delay in the time to get a vessel open, from the time they first started having the stroke, there is a 10 percent lower likelihood that they will have a good neurological outcome after their stroke,” Pugh explained. “So, we are looking to save minutes. The primary challenge we have in treating stroke today is you lose hours outside of the hospital for patients to get to the right place. The procedural duration, once a patient gets to a neurovascular catheterization lab to have the procedure done, is getting quicker and quicker.”
Clinical Prowess Provides Expedient Clearance
So what is the buzz about Medtronic’s new Riptide aspiration system all about? It seems that it’s not so much about what they did, but how quickly they were able to it.
“Are we bringing anything new with Riptide that has not existed? No, we’re not. What we are bringing is Medtronic quality, and the Medtronic portfolio as a whole to a segment of the market we have not played in,” Pugh explained. “There has been a lot of discussion and debate, some of it coming from the fact that other companies have been unable to get this clearance without a requirement for clinical trial data. The bit of a shock, if you talk to some of the physicians in the market and the market analysts, was that the clearance of the Riptide aspiration system came much earlier than they were anticipating, since clinical data was not required. We did not conduct a clinical trial specifically to get this indication. We had extensive amounts of prior data, bench data, and pre-clinical data that the FDA felt was sufficient to get the clearance on the catheter for aspiration.”
Two Camps For Treatment Of Large Vessel Occlusions
I asked Pugh about the procedure for treating stroke in the hospital, and she explained:
They bring the patient in and do a groin stick, just like they were going to do a cardiac catheterization. They navigate up through the aortic arch, into the carotid arteries, and into the vessels deeper in the brain to get to where the clot is. Some doctors will take a large-bore catheter right up to the clot, cross the clot with a stent retriever, open the stent retriever, embed the clot, and then pull it back into the catheter and pull it out of the patient. As these catheters started getting better and larger, physicians would get the catheter up to the clot and try to tug on it with aspiration to see if they could get the clot to clear without deploying a stent in it. There has been some debate about which is the best approach, and which affords the best outcome. Some camps have evolved: one that wants to try aspiration first and then use a stent when needed, [and] another camp that always wants to use a stent with the catheter. As we get more data, we are going to understand where the aspiration-first approach may actually work a certain percentage of the time. If it does, the ability to simplify a procedure, maybe not pull a secondary product that costs money, could provide a potential financial benefit. But how do we go about evolving where that works? We need it to work, and we need it to work quickly, because every minute counts for these patients.
Importance Of Stroke Diagnostics
Remembering one of the first articles I wrote when I joined Med Device Online was on Forest Devices’ ALPHASTROKE, an early screening device for ischemic stroke, I asked Pugh’s take on new technologies targeted at getting patients to the proper care centers. Her response was rather positive.
“Diagnostics are going to provide one of the biggest changes in stroke care. Our ability to identify those patients in the field that need to get to a comprehensive center quickly could make a significant difference in patient outcomes. If a patient goes to a primary stroke care center, but then needs to be transferred to a comprehensive care center, the resulting delay is at least 90 minutes — 90 times 1.9 million, I don’t have that many neurons to lose,” Pugh said. “So, I think this is a very exciting space; we have some small investments in diagnostics, and I am spending a lot of my time there. If we could get patients to definitive care — meaning getting them to a comprehensive center with mechanical thrombectomy in 90 minutes — we would approach the number of 90 percent of the patients being what we would call good neurological outcomes, meaning minimal disability from a major stroke.”
Finally, Pugh told me horror stories about patients taken to primary stroke centers who needed to be transferred to comprehensive centers, but were literally driven past multiple non-affiliated hospitals with the ability to provide mechanical thrombectomy, only to be taken to a more distant hospital that was affiliated with the primary stroke center. Can you imagine how you would feel if this happened to one of your loved ones?
“The stroke system in the United States today is broken. Today, we fight in technology for minutes in the procedure, but unfortunately we lose hours outside of the hospital in terms of getting stroke patients to the right location for care. We are going to continue to fight for those minutes because that’s what we do as a technology company. That’s the piece we own, but we will continue to advocate for the real battle, which is getting patients to the right center of care as quickly as possible,” Pugh concluded.