2002 IAGS Proceedings: Intracranial Interventions (Part I of II)
- Volume 15 - Issue 2 - February, 2003
- Posted on: 8/1/08
- 0 Comments
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Max Amor: I have no magic bullet, but I think that politics are an extremely important component of this issue. In France in the past ten years, I have not seen any changes in the approach to treating stroke. There are still efforts to make advances in some centers, but I have realized that it is very difficult to convince neurologists to enter into that domain. It has also been difficult to convince neuroradiologists to involve cardiologists in stroke treatment. I would say that the situation has been quite stagnant in my country over the past four to five years. From my experience with carotid angioplasty and carotid stenting, I think it is extremely important to organize collaborative, multi-disciplinary studies on an international, European, and national basis. These types of studies show local practitioners how to treat stroke. Perhaps the IAGS could have a role in defining a multidisciplinary territory to convince local practitioners to work as a team. If we don’t do this, we will continue holding meeting after meeting while the stroke situation remains unchanged. Likewise, industry will have no incentive to invest money in stroke research.
Gary Roubin: I called Richard Stack twelve years ago to ask how I could get our people organized at UAB to improve stroke treatment. Following Richard’s advice, I got interventional radiology and neuroradiology involved. It is important for the group here to understand that it was actually at the IAGS meeting ten years ago, attended by Bob Ferguson and a few other interventional radiologists, where we had discussions like this one today regarding carotid stenting. That meeting ten years ago gave us the confidence to join with Jiri Vitek and get carotid stenting started. There has been a major change over the last decade in the way that carotid disease is treated, and it started with this group. This change is something we should be able to replicate in other areas as well. I would be interested to know what Fayaz Shawl, Howard Cohen, and perhaps some of our South American colleagues think about this.
Some of the practical issues we need to address involve finding ways to share information and ideas, overcoming some of the interdisciplinary barriers that we face, and getting major players such as Cordis, Boston Scientific, and Guidant more involved in bringing different disciplines together. For a number of years thought leaders such as yourself, Nick, have acknowledged that there will be no progress in stroke intervention without the help of interventional cardiology. The national bodies of neurology have just recently acknowledged that interventional cardiologists are far ahead in acute myocardial infarction intervention and now have many experienced operators available to help in acute stroke intervention. And yet, we are still struggling. We should perhaps turn this discussion over to those of you who come from some of the largest centers in the country — many of them very influential academic centers such as Mayo Clinic, Montreal Heart Institute, and Duke, which has the largest interventional laboratory in the country. As a society, the IAGS doesn’t quite have the “muscle,” but with companies like Cordis, Guidant, and Boston Scientific behind us, we can get organized.
Tom Linnemeier: Medical technology seems to be outpacing the medical subspecialties. There is nothing you showed us, Nick, that can’t be fixed with the devices currently available from the major catheter companies. This is a good place to start, but I think that industry is hoping that medicine will move things forward. You can give example after example of failure for every successful Lenox Hill or Duke. One such example would be at my own institution, St. Vincent Hospital, where we thought we would solve the interventional radiology problem by hiring Don Schwarten. Within a two-week time period, the vascular surgeons hired their own interventional radiologist and Dan sat around for a long time with nothing to do. This is a very complex subject with complex dynamics. It requires someone like Nick Hopkins to stand up and say that interventional cardiology and neurology ought to work together. I am glad to hear that the American Heart Association is encouraging interventional cardiologists to get involved with stroke intervention. Some of our own societies such as the AMA, the ACC, and the AHA have some relatively conservative views on how this ought to be handled. There certainly are some influential people in this room today — so let’s work through the professional societies to help move this technology forward.
Nick Hopkins: One of the biggest problems is that we fail sometimes and we will continue to experience failures in some of our cases, with devastating outcomes. The neurology community is tightly focused on clinical research and outcomes, as well they should be. However, a very powerful force against the new technology crops up when a disaster occurs. We experienced a huge battle at our institution following a failed procedure that resulted in committee hearings. It was just awful. Neurology basically said, “You had a hemorrhage here; the patient died.” I told the committee that the patient had an NIH stroke scale of 23 when we started, which is worse than death by almost anyone’s definition. Yes, the patient died. He died because he had a hemorrhage. But frankly, if it were my stroke, I would hope you would intervene on me — I’ll take my chances, thank you. Progress will come only when we train more neurologists who will then go back to their institutions and preach the gospel to their colleagues. As Gary Roubin said, the neurology meeting represented an enormous breakthrough this year because there was finally a recognition that they need the help of cardiology. Neurology still represents a major hurdle, however. They will hold our feet to the fire, as they should, but we must bring them along.
Tom Linnemeier: Generally speaking, one doesn’t become a neurologist because one enjoys performing acute interventions. I’ve watched Gary Roubin get shot down so many times over the past fifteen years for performing carotid angioplasty, I don’t know how he’s still standing! The amount of grief Gary has taken is unbelievable. It takes people like Gary, Andreas Gruentzig, Richard Myler, and Eberhard Zeitler, to stand up and say: “Yes, we will have complications, but we need to move this technology forward.” It takes courage, charisma, and perseverance. I guarantee you that Andreas Gruentzig did not back off when a patient died or when a patient had a complication. We simply wouldn’t be gathered here today if not for the courage of these men.
Doug Cavaye: I am a vascular surgeon. My intervention work ends in the carotid artery. I have jotted down some comments which all happen to start with the letter “p.” The first “p” represents the concept of a neurological penumbra — an area of ischemic or dying brain cells that are electrically negative and that may or may not be able to be rescued. Thus, the concept of a penumbra implies that time is very important. If a patient has a deficit that lasts for 60 minutes, my understanding of the literature is that he has about a one in four chance of rescue. If the deficit is present at two hours, the patient has a less than 10% chance of the event being a transient ischemic attack. In other words, a stroke is established in more than 90% of patients at two hours post-event. Thus, getting a patient to the hospital — which is the second “p” for protocol — is just as important as the penumbra. The third “p” is for perforators, which are deadly little arteries. You can’t blow up a balloon 2 cm long in intracerebral vessels without getting a perforator, and it is difficult to predict the occlusion’s locality. A perforator occlusion is dramatic and disastrous. The final “p” — for pharmacology — is something we have not yet discussed. Many of the cardiological improvements, or rescues of cardiac interventions, have relied on pharmacology — whether these are anticoagulants, lytic agents, or anti-spasmodics. What is the current situation with intracerebral or neurological pharmacologic rescue? From what I understand, very few agents are effective.
Nick Hopkins: You talked about the window of time, the first “p.” In certain circumstances a stroke is indeed likely to be established within two hours. But everything depends on the substrate. For patients with no underlying collateral, there may not be very much penumbra. That’s actually one of the big “bugaboos”: we have difficulty determining which patients will do well and which ones will not. If you see a big infarct on the CT scan, you know the patient is cooked; there’s nothing you can do. But if you don’t see a big infarct on the CT scan, you don’t really know the status of the penumbra. There is no test available yet to quickly assess a patient’s condition. We have all seen patients — particularly cases involving the vertebral-basilar system — who were as long as 12, 14, even 24 hours out, were locked in neuroradiology, and who then made dramatic recoveries when their vessel was opened up. As for the pharmacological aspect, we are trying to inch our way along at our center with small numbers of patients. We’ve been reporting groups of 15 to 20 patients, with 15 patients in thrombolysis alone. There was a high rate of hemorrhage and a relatively low rate of reperfusion in these patients. If we used thrombolysis plus mechanical disruption of the clot, 85–90% were reperfused, but there was still a significant incidence of hemorrhage. Now with a much lower dose of thrombolytics and the addition of abciximab, we are achieving much better reperfusion and many fewer strokes. We still experience a good number of failures, however. We are now looking toward opening the window of time with techniques such as cooling, which a lot of previous work has shown to be the best brain protectant available. Thus, we are inching along with the same pharmacologic agents that are being used in cardiology, but it’s a slow process and it’s difficult to get patients into the centers. Neurology does control most of the strokes and we must keep working to convince them that we should be entering these patients in the experimental trials.
Chris Cates: I want to revert back to what we were discussing earlier. I have done carotid work since 1994 after training under Gary Roubin. I am constantly amazed at the visceral response that carotid stenting by cardiologists evokes in colleagues who are on the multi-disciplinary team. It seems that at the early, vestigial phase, there is a lot of camaraderie. However, as soon as success and notoriety come along, a visceral reaction — subtle nastiness —takes over. The quality assurance process is used in every way possible to stifle the program. Given that, I would like to address what Paul and Tom have said about industry’s influence. Paul said that because not many physicians are involved in stroke intervention, it is difficult for industry to justify expenditures in that area. On the other hand, you (Paul) and others have done a lot to try to be politically correct and develop the protocols for the very small group that you were just complaining about. One way to “enlarge the pie” would be to start involving cardiology more in those protocols. In fact, instead of putting the stroke protocol with the typically anti-intervention neurology group, give it to the group you want it to grow with, which is cardiology. Let the others either join in or not. This would be a way to justify from the company’s and the FDA’s point of view that the physicians you involve in this protocol are in fact eligible to perform the procedures it calls for. I think this type of strategy will have a much greater impact on the marketplace than you think.