EXPERT ANALYSIS FROM EUROPCR 2015
PARIS (FRONTLINE MEDICAL NEWS) – The leaders of European interventional cardiology have thrown down the gauntlet to their colleagues, declaring during a special call-to-action session at EuroPCR that a revolution is underway in the treatment of acute stroke, and interventional cardiologists need to train up and become part of it.
“Something big is going on today. If we want to be transformative and impactful, I think stroke intervention is one of the main points where we can do so as interventional cardiologists,” said Dr. Alberto Cremonesi of Villa Maria Cecilia Hospital in Cotignola, Italy, a past president of the Italian Society of Interventional Cardiology.
Dr. Petr Widimsky highlighted the five prospective, randomized, controlled trials that have come out in the past few months and triggered the revolution in acute stroke therapy. All five studies – MR CLEAN , ESCAPE , EXTENT IA , SWIFT PRIME , and REVASCAT – were halted early because of the significant advantage mechanical endovascular therapy with stents or thrombus retrieval devices demonstrated over standard therapy featuring clot thrombolysis with tissue plasminogen activator.
Collectively, the five trials showed a 60% greater chance for good functional recovery from stroke with endovascular interventions. The rate of a favorable neurologic outcome as reflected in a modified Rankin score of 0-2 was 48% with the use of stent/retriever devices, compared with 30% with thrombolysis alone, noted Dr. Widimsky, professor and chair of the cardiology department at Charles University in Prague.
The Food and Drug Administration began approving these endovascular therapy devices in 2012. The major challenge is how to make this therapy available to the vast numbers of patients in need. After all, the successful clinical trials were carried out by highly skilled interventional neuroradiologists operating in centers of excellence – yet such centers are few and far between.
“There should be no fight between the specialties. In hospitals with high patient volume and good work flow and experienced neuroradiologists available 24/7, there is no need for cardiologists to jump in. But in hospitals where that’s not the case then cardiologists can be of help,” he asserted at the annual congress of the European Association of Percutaneous Cardiovascular Interventions.
There aren’t nearly enough interventional neuroradiologists or endovascularly trained neurosurgeons to fill the enormous need, and neurologists simply don’t have the mindset for this sort of work, Dr. Widimsky added.
“Neurologists, with few exceptions, don’t do interventions. In general, they are people who think conservatively. These procedures should be done by someone who is working with procedures every day, and that’s not what neurologists do,” he continued.
Because interventional neuroradiology services weren’t available at Dr. Widimsky’s hospital, he and his fellow interventional cardiologists took on the task several years ago, gaining specialized training and then forming a multidisciplinary acute stroke team. The results, he said, have been gratifying.
The new endovascular therapy for acute stroke has much in common with contemporary management of ST-elevation MI, Dr. Widimsky observed. Just as in an acute MI, where time is heart muscle, in acute stroke time is brain. In most patients, the endovascular procedures are most effective when done within 3 hours after acute stroke onset. By 6 hours, the rate of good functional recovery falls to about 20%. But some patients can derive benefit even with much later intervention provided they have sufficient collateral circulation, which can be determined by sophisticated perfusion imaging techniques.
Dr. Widimsky pointed out a couple of ways to streamline today’s standard acute stroke management flow in order to save substantial time. The typical pathway today is for EMS personnel to take a patient to the emergency department for evaluation for suspected stroke, which can take up to 30 minutes. That patient then goes to CT imaging to determine whether the stroke is ischemic or hemorrhagic, then to the neurology unit for thrombolytic therapy, which can take another 30-60 minutes. Only afterwards, if indicated, does the patient go to the catheterization laboratory for endovascular intervention.
A faster, better approach, he said, is to train EMS personnel to recognize suspected cases of acute stroke, have them bypass the ED and instead take those patients straight to a hospital with high-quality CT imaging available 24/7, and if imaging indicates the patient is a candidate for mechanical revascularization, to then bypass the thrombolysis suite and go directly to the catheterization laboratory. That can save an hour to an hour-and-a-half in total.
Who should be performing these endovascular interventions? Dr. Alain Bonafe presented highlights of a recent joint consensus statement by the European Stroke Organization, the European Society of Minimally Invasive Neurological Therapy, and the European Society of Neuroradiology that declared the decision to undertake these procedures should be made jointly by a multidisciplinary team in experienced centers providing comprehensive stroke care, and that the procedures should be carried out by accredited interventionalists with certified expertise, regardless of their specialty.
“We must offer this intervention to as many patients as possible,” stressed Dr. Bonafe, professor of neuroradiology at the University of Toulouse and president of the French Society of Neuroradiology. “In most places it’s not offered at all, or only part-time by a few experts. So I think cardiologists should join the force, and everybody who is expert in procedural interventions should be trained for this in order to cover the need for the whole population.”
Dr. Kenneth K. Snyder observed that as recently as 2013, the rumor was that endovascular stroke therapy was dead. Three randomized trials published in the New England Journal of Medicine – IMS III , SYNTHESIS , and MR RESCUE – had found no difference between endovascular therapy and standard medical therapy.
But only 5% of the participants in those trials were treated with modern clot retrievers, which are much more effective than earlier-generation devices. And the negative trials didn’t specifically target large-vessel occlusions, which is where device therapy clearly works best.
“Stroke is now a surgical disease. Many of us have believed this from the get go. In centers with advanced systems of stroke care, endovascular therapy can significantly improve functional outcomes without compromising safety as compared to standard therapy,” said Dr. Snyder, a neurosurgeon specializing in endovascular therapy at the State University of New York at Buffalo.
In the United States, he noted, stroke is the fourth leading cause of mortality, the No. 1 cause of long-term disability, the most common discharge diagnosis to nursing homes, and carries a cost of $70 billion annually. Worldwide, stroke is the second leading cause of mortality. And stroke rates will continue to grow.
He said conflict between specialties regarding provision of state-of-the-art acute stroke therapy is not inevitable, as can be seen at the acute stroke unit at SUNY Buffalo.
“Our center is collaborative and multidisciplinary. We have 20 interventional suites. We all work next to each other and with each other – the cardiologists next to the interventional radiologists next to the neurosurgeons. It forces a great deal of collaboration. And we have a track record of training cardiologists both in observerships and also in formal training programs,” Dr. Snyder said.
The speakers declared having no financial conflicts.