Spring 2010 - Stroke: Surviving & Thriving
More Americans are surviving strokes and experiencing fewer permanent side effects than ever before, thanks to dramatic advances in technology and minimally invasive techniques.
Hippocrates, the father of medicine, was the first person to recognize and describe ischemic stroke — the most common type of stroke — some 2,400 years ago. He called it “apoplexy,” which, loosely translated from Greek, means struck down by violence. A person with apoplexy was suddenly “struck down” by paralysis, which led to the use of the term “stroke” as a synonym for apoplectic seizure. References to the word stroke date back to 1599.
In the days of Hippocrates and his successors, there were few treatment options for stroke sufferers. Today, it’s a different story.
“At primary stroke centers like ours at WakeMed, consistent teamwork has led to reduced length of stay and reduced mortality in cases of acute ischemic stroke,” says Dr. Keith Hull, a neurologist with Raleigh Neurology Associates and director of the WakeMed Stroke program, who recently returned from the International Stroke Conference. Heart to Heart had the opportunity to speak with Dr. Hull and his physician colleagues in WakeMed Heart & Vascular Services about the latest stroke treatments.
Thrombolytics & t-PA
In the case of ischemic stroke, a thrombolytic drug is administered intravenously to help dissolve blood clots in arteries and reestablish blood flow to the brain. “A stroke is a dynamic process that typically kills 2 million nerve cells per minute over approximately eight hours,” says Dr. Hull. “When the thrombolytic drug is administered, it can interrupt the stroke and prevent loss of more nerve cells. Our stroke team has been working to improve the efficiency of collaboration among hospital departments to allow for earlier interruption of the stroke process.”
The first thrombolytic for stroke treatment was approved by the Food & Drug Administration in 1996. That thrombolytic is a man-made enzyme called tissue plasminogen activator (t-PA) — an enzyme that changes or activates plasminogen in the human body into another enzyme that can dissolve a blood clot.
Initial t-PA trials revealed that the drug is most effective when administered within three hours of the onset of symptoms. “In terms of stroke outcomes at three months, the administration of the thrombolytic drug at one hour after stroke symptom onset is 3.5 times more effective than administration at three hours after symptom onset,” says Dr. Hull. “Earlier administration is better. Our primary goal remains to be prompt administration of IV t-PA to appropriate patients as soon as possible after the onset of symptoms.” A current international study is beginning to produce evidence that t-PA may also be effective up to 4.5 hours after the onset of symptoms — another potential advancement in stroke treatment. “Because that window for successful treatment might be widening from a research perspective does not mean you can take your time getting to the hospital if you are experiencing stroke symptoms,” warns Dr. Hull. “The faster you get treatment for stroke the better your chances of a full recovery will always hold true.”
Technology to Actually Remove Clots
What about those patients who do not make it to the hospital within three hours of stroke symptom onset or those who are not candidates for t-PA?
“In general, t-PA is not recommended for stroke patients who are beyond the three-hour window after the onset of symptoms,” says Dr. Ravish Sachar, an interventional cardiologist with Wake Heart & Vascular Associates and the WakeMed Heart Center. “There are also multiple medical conditions, such as a recent stroke, history of excessive bleeding, severe hypertension, a known brain aneurysm, and many others which increase the risks associated with IV t-PA.”
Help in fending off the debilitating side effects of stroke for these types of patients and those who simply do not respond to t-PA therapy arrived in 2004 with the introduction of the Merci Retrieval System®. “The Merci retriever is a coil that an interventionist threads through the artery with a catheter,” explains Dr. Sachar. Once it reaches the clot, it coils around the clot, trapping it so the interventionist can pull it out of the artery. Once the clot is dislodged and retrieved, blood flow returns to the brain.
Interventionists at WakeMed also use a different type of technology to remove clots and stop strokes in their tracks. FDA approved in 2008, the Penumbra System uses suction instead of a coil to pull the clot out of the artery. “For some interventionists, the Penumbra offers an advantage because you don’t have to feed a coil all the way up to the clot,” says Dr. Matthew Hook, who is also an interventional cardiologist with Wake Heart & Vascular Associates and the WakeMed Heart Center. “Both technologies are effective; the one that’s used really depends on physician preference.”
Angioplasty & Stenting
Doctors Sachar and Hook also use angioplasty, a procedure commonly used to open blocked coronary arteries, to return blood flow to the brain. The interventionist threads a catheter containing a balloon to the site of the blocked carotid artery then inflates the balloon to open the artery. The interventionist may also place a stent, a tiny device made of metal mesh, at the site of the blockage to help prevent future blockages that could cause strokes.
Medical Conditions that Increase Stroke Risk
Certain medical conditions can increase the risk of having a stroke. Fortunately, effective treatment is available for these conditions at WakeMed.
Hole in the Heart — All unborn babies have a small opening between the upper chambers of the heart called the foramen ovale. Its purpose is to redirect blood away from the lungs before birth. Once born, a child no longer needs the opening. “The hole typically closes during the first months after birth,” explains Dr. John Rhodes, a pediatric cardiologist affiliated with Wake Heart & Vascular Associates and the WakeMed Heart Center. “But sometimes the hole doesn’t close. The person is then left with a type of birth defect called a patent foramen ovale (PFO).” The American Heart Association estimates that one in fi ve healthy adults have a PFO.
Small PFOs may not cause any problems for children or adults. “It’s the larger PFOs that can cause serious issues,” says Dr. Rhodes. A blood clot can travel through the hole in the heart and into the brain to cause a stroke.
Today, the treatment for a PFO is typically minimally invasive, which means decreased pain and blood loss and a faster recovery over traditional open surgery. “We use a catheter to thread a patch through the artery,” says Dr. Rhodes. “When we reach the hole, we essentially patch it and remove the catheter.” The procedure is recommended for children who have large PFOs to prevent issues later in life and for adults who experience symptoms. Stroke, migraine headache, and shortness of breath during exercise are possible symptoms of PFO.
Surviving & Thriving
Innovations in technology and technique continue to help stroke specialists at WakeMed save more lives and decrease the chance of permanent disability. Though WakeMed stroke specialists are armed with the latest tools and expertise to help patients survive and thrive after stroke, they all agree that some not-so-recent advice still holds true: If you think you or someone you are with is having a stroke, call 911 and get to your closest emergency department. The faster you receive treatment, the better your chances for a full recovery and return to living your life.
Primary Stroke Center Certification: What It Means for You
WakeMed Health & Hospitals is the fi rst and only health system in the Triangle to offer a comprehensive stroke program that is certifi ed by The Joint Commission on Accreditation for Health Care Organizations. The certifi cation applies to stroke care provided at the WakeMed Raleigh Campus, WakeMed Cary Hospital, WakeMed North Healthplex and WakeMed Apex Healthplex.
So, what does it mean? “When a health system earns Joint Commission Primary Stroke Center certifi cation, it means that the system is using practices and processes that are proven by national research to be the best way to care for stroke patients,” says Dr. Keith Hull, director of the WakeMed Stroke program.
“Certification requires us to have certain practices and people in place,” says Dr. Hull. Some of these include ongoing stroke-related quality improvement initiatives, a dedicated acute stroke team readily available 24/7, specific protocols in the WakeMed Emergency Departments to ensure patients receive testing and treatment as quickly as possible, and a specialized hospital unit for stroke patients.
Regaining Your Rhythm
Atrial fi brillation is a serious heart rhythm problem in which the heart’s two upper chambers quiver instead of beating regularly. Dr. Matthew Forcina, an electrophysiologist with Wake Heart & Vascular Associates, and Dr. Pavlo Netrebko, an electrophysiologist with Cary Cardiology, are two cardiologists who specialize in the treatment of atrial fi brillation at the WakeMed Heart Center. “A normal heart rhythm effectively pumps blood through the heart’s chambers and ventricles,” says Dr. Pavlo Netrebko. “When a person has atrial fibrillation, the blood is not efficiently pumping through the heart. If atrial fibrillation is left untreated, blood can pool, clot and then travel to the brain and eventually cause a stroke.” According to the American Heart Association, people who have atrial fibrillation are five times more likely to have a stroke than people who have normal heart rhythms.
As Dr. Forcina explains, “There are several effective treatments to control and even eliminate atrial fi brillation.” Medication to control an abnormal heart rhythm is the fi rst step. When medication doesn’t work, electrical cardioversion is often the next step. The cardiologist uses electricity in an attempt to “shock” the heart into a normal rhythm.
“When medication and cardioversion do not work, the next option is radiofrequency ablation,” says Dr. Forcina. Radiofrequency ablation can permanently cure atrial fibrillation and, in many cases, eliminate the need to take blood thinners like warfarin. Both Dr. Forcina and Dr. Netrebko perform radiofrequency ablation at WakeMed. During the procedure, a thin tube is directed through a blood vessel to the heart. Radiofrequency waves are then used to destroy — ablate — the tissue causing Dr. Pavlo Netrebko abnormal electrical activity in the heart.