Future of Stroke Therapy to Include More Stroke Centers, Telemedicine, and New Approaches to Opening Blocked Arteries
ARTICLE IN BRIEF
A stroke expert highlights changes needed to improve stroke care.
WASHINGTON—The field of stroke therapy will change over the next 10 years, and these changes will benefit men and women, said James C. Grotta, MD, professor and chairman of the department of neurology at the University of Texas Medical School.
Speaking at a symposium on women and stroke, Dr. Grotta, who is director of the Stroke Program at the University of Texas, predicted that stroke centers, telemedicine, and new treatments will improve US stroke outcomes. The symposium, held on Capitol Hill in February, was sponsored by the Society for Women's Health Research and the Hazel K. Goddess Fund for Stroke Research in Women.
Stroke is the third leading cause of death among women, and stroke in women is an ongoing epidemic, accounting for more than 60 percent of all US stroke deaths.
Currently the only approved treatment for stroke is the clot-dissolving drug tissue plasminogen activator (tPA), Dr. Grotta noted. “tPA is maximally effective if treatment is started within 90- to 120-minutes of symptom onset, and presently the drug is approved only up to three hours,” said Dr. Grotta. “Based on recent data from Europe, guidelines will probably be changed to allow treatment out to 4.5 hours, but the benefit at such an extended time window is minimal.”
tPA is not a panacea, but can open a blocked artery in about 20- to 50-percent of cases, said Dr. Grotta. Today, however, only 2- to 5-percent of stroke patients receive tPA, a dismal statistic that must be changed, he said. “Patients don't act fast enough and call 911,” he said. Further, “They are taken to hospitals that are not prepared to give the drug, and many eligible patients are not treated (with tPA) even at stroke centers.”
CHANGES FOR BETTER MANAGEMENT
To change this picture, Dr. Grotta said management of stroke in the future will involve a number of changes. First, he said, stroke patients must have access to the best care, and that means development of more US stroke centers, stroke teams, better systems organization to improve patient access, and better coordination of emergency medical services. “We have to develop stroke centers in virtually every community,” said Dr. Grotta. He noted that states are now passing legislation to ensure faster patient access to optimal stroke treatment and stroke system development.
Second, Dr. Grotta predicted that treatment of stroke will increasingly rely on telemedicine. “Telemedicine can provide stroke (and other specialty expertise) to hospitals without specialty coverage,” he said, noting that half of stroke patients are currently treated in hospitals with less than 100 beds. In his hospital, he said, he covers 20 other Texas hospitals through telemedicine. “It's really a two-way interaction; I can examine the patient remotely with the nurse there.”
Dr. Grotta said telemedicine infrastructure is an ideal target for the recently passed economic stimulus legislation, because currently there is no coordination of telemedicine services. Noting that in Texas physicians need a telemedicine license, Dr. Grotta said the field has to be properly regulated and its reimbursement mechanisms established, but it has “huge potential benefits.”
Dr. Grotta predicted the development of new developments in reperfusion designed to open blocked arteries faster and more completely. He cited ultrasound-enhanced lysis in addition to using ultrasound diagnostically to identify artery blockage. “Ultrasound-enhanced clot lysis is an important goal of the future,” he said. “Adding microbubbles amplifies the effect of ultrasound.” In addition, he cited anticoagulants such as thrombin inhibitors and platelet inhibitors, which are being tested in conjunction with tPA.
Dr. Grotta also predicted that there will be greater use of interventional endovascular techniques that use catheters to deliver drugs and mechanically disrupt a clot. This interventional approach “can get the artery open in 80 percent of cases including larger clots resistant to tPA,” he said, adding that such an approach may be applicable up to 12 hours after symptoms in selected patients.
Neuroprotection is another approach that will be employed in stroke management in the future, predicted Dr. Grotta. “The concept is to reduce tissue damage by targeting the physiologic problems that are triggered by the interruption of blood flow,” he noted. He said several neuroprotective treatments are under investigation, including caffeinol, a simple mixture of low doses of caffeine and ethanol; magnesium (started pre-hospital in the ambulance); albumin; and hypothermia. In the latter case, he said, “This is an area of intense investigation at the present time…Improved technical methods to achieve cooling are a priority.”
Implicit in the management of stroke is the “emerging concept that the brain has some limited restorative capability,” said Dr. Grotta, and that plasticity means the brain can form new connections and take over the function of damaged areas. Thus progenitor cells and non-embryonic pluripotent cells from bone marrow will continue to be studied to enhance recovery from stroke, he predicted. He also predicted wider use of growth factors, which he likened to “little factories” to improve recovery, and said that phototherapy (infrared laser beams) and oxygen may be used to “kick-start idling neurons to stimulate recovery and plasticity.”
While there is currently no blood test for stroke, Dr. Grotta predicted that one will be developed in the future based on biomarkers. This test, he said, could theoretically be “based on gene expression, ‘turned on’ by stroke, and reflected in proteins circulating in the blood.” Thus, “measuring these proteins in the blood will identify stroke patients, and perhaps distinguish between infarct and hemorrhagic stroke, duration of stroke, existence of ‘penumbral’ tissue (tissue that is still alive but threatened), etc.” And, he predicted, studies on genetic variability in responses to various stroke therapies will help physicians individualize treatments “according to a patient's genetic profile.”
Asked by Neurology Today what can be done to alert the public to the critical importance of getting help for stroke symptoms early, Dr. Grotta said, “I don't think anybody knows how to change public behavior.” But, he added, “We have to do more than just put up a few billboards. We need to create a whole generation of more aware consumers.” This increased awareness, he said, must also extend to prevention.