STROKE
- Every 45 seconds, someone in America has a stroke.
80% could be avoided by 5 modifiable risk factors:
quit smoking, avoid excess alcohol, exercise daily, control hypertension, control high cholesterol.
MRI of brain shows right subacute ischemic stroke due to large-vessel
thrombosis in the middle cerebral artery.
Stroke Signs and Symptoms:
Come on Suddenly
If you notice any signs or symptoms of a stroke, call 911 immediately. The chance that you will survive and recover from a stroke is higher if you get emergency treatment right away.
What You Need to Know About Stroke Now:
Stroke can affect your senses, speech, behavior, thoughts, memory, and emotions. One side of your body may become paralyzed or weak. If you have minor or resolving symptoms, still seek emergency assistance right away. Strokes are always of SUDDEN onset.
According to the American Stroke Association, dial 911 if you or your companion experience any of the following:
- Sudden numbness/weakness on one side of body/face/arm, or leg.
- Sudden confusion or trouble speaking or understanding others.
- Sudden trouble seeing in one or both eyes.
- Sudden dizziness, trouble walking, or loss of balance or coordination.
- Sudden severe headache with no known cause.
Signs of a stroke always come on suddenly.
If your symptoms go away after a few minutes, you may have had a "mini-stroke," better called a transient ischemic attack (TIA). TIAs do not cause permanent damage but can be a warning sign of a full stroke—you should still get help immediately.
Though stroke is the third leading cause of death in the United States, most stroke victims survive.
However, many survivors don’t fully recover, making stroke a leading cause of long-term disability in adults. About 4.4 million Americans live with stroke-related disabilities, and half of them are partially or totally dependent on someone else for their daily activities.
- If you or someone else experiences one or more signs or symptoms of stroke, call 911 immediately.
- TAKE NOTE OF THE EXACT TIME OF ONSET; WRITE DOWN THE TIME THAT SYMPTOMS BEGAN AND TELL THE DOCTORS.
- Don't try to drive yourself to the hospital.
- Paramedics can begin treatment if necessary and can triage the situation, so that the hospital can give appropriate care more quickly and effectively.
"Time Lost is Brain Lost": the more quickly you seek care, the more likely you are to qualify to receive brain-saving medication.
Mechanisms of Stroke
A stroke is due to an interruption of the normal blood flow to or in the brain. Another term is cerebro-vascular attack (CVA). There are different types of mechanisms for the development of a stroke. The most common type is ischemic stroke that occurs as a result of a clot that slows and stops the flow of blood into an area of the brain. Ischemic stroke is again subclassified.
Embolic stroke occurs when a clot travel upstream into a cerebral artery and gets lodged so that blood cannot flow. The clot, or embolus, is formed, in susceptible individual in the heart or the carotid arteries of the neck. Ischemia of a stroke may also occur due to thrombosis, which is a blockage in an artery by fatty deposits related to cholesterol metabolism. The ischemic stroke cannot always easily be distinguished as embolic or thombotic.
Now, a further, sub-subclassification is rather important due to the vast difference in prognosis for the patient with the stroke. A thrombotic stroke is usually less severe when it is the result of small-vessel disease. This type of stroke is due to thrombosis in a very small artery found deep in the brain at the end of the arterial branches, just like a tree has large trunks and many, many small branches. This is a lacunar stroke since imaging later shows a small black or white space, an emptiness or a hole, called lacuna in Latin. The particular risk factors for this outcome are hyperlipidemia with uncontrolled cholesterol in the blood stream, high blood pressure, and diabetes mellitus.
More severe strokes are the result of large-vessel thrombosis. One of the large arteries into the brain has been blocked so that a large segment of the brain is deprived of blood, oxygen and nutrients. Therefore, a large stroke follows with much more significant outcome for the patient. The arteries affected are most often the internal carotid artery or the immediate large truncal branches within the brain of the middle or anterior cerebral arteries.
Poor outcomes also follow thrombosis of the arteries in the back of the brain, the vertebral, basilar and posterior cerebral arteries. The cause if often the combination of a thombotic artery suddenly blocked by a small clot in the residual narrowed lumen of the artery. The risk factors are similar to those of small-vessel disease, but these patients are much more like to have underlying and severe cardiac disease, so that large-vessel stroke and heart attack may occur in the same patient at different times.
If the CVA is not ischemic due to too little blood flow, it is the result of bleeding, called hemorrhagic stroke, after the rupture of an artery inside the brain. The onset is also very sudden, but more often catastrophic. The eventual outcome is worse, with more frequent deaths and prolonged disability. Intracerebral hemorrhage are usually due to uncontrolled hypertension, but many other causes will be considered by the doctors attending to this patient that almost invariably is admitted to the Intensive Care Unit of our hospital, rather than a regular floor.
A particular type of intracerebral bleeding that is infrequent but devastating is the subarachnoid hemorrhage (SAH). There are indeed benign types of SAH, usually in the back of the brain from a ruptured vein, rather than an artery. Most types of SAH follows the tear in the weakened arterial wall, bulging into a pouch called an aneurysm. Treatments of these have changed rapidly the last decade. Neurosurgical procedures are now rarely done; instead, the patient is managed initially by an interventional neuroradiologist. Yet, the outcome is sometimes disappointing. Risk factors are cigarette smoking, hypertension, and family history. Family history is significant only for first degree relatives, NOT grandparents, aunts, uncles, or first cousins. It is NOT appropriate to screen for aneurysms when a headache patient reports a distant relative with SAH or aneurysm!!
Stroke Risk Factors
Anyone can have a stroke no matter age, race or gender. But, the chances of having a stroke increase if a person has certain risk factors, or conditions that can cause a stroke. The good news is that many strokes can be prevented, and the best way to protect yourself and loved ones from stroke is to understand personal risk and how to manage it.
Some risk factors for stroke are controllable and others are not. Controllable risk factors generally fall into two categories: those that the individual is responsible for by life-style, and those that are medical risks that need intervention by a medical doctor. Lifestyle risk factors can often be changed, while medical risk factors usually can be treated with medications. Both types are managed best by working with a doctor.
Uncontrollable Risks
After the age of 55, stroke risk doubles for every decade a person is alive.
Women suffer more strokes each year and more disability after stroke than men. Since women live longer than men, and stroke occurs more often at older ages, more women than men die from stroke each year. However, at younger ages, men have stroke more often than women.
African Americans have twice the risk of stroke when compared to Caucasians. Hispanics and Asian/Pacific Islanders also have stroke higher stroke risks.
Family history of stroke indicates the presence of a genetic predisposition. This risk is significant for first degree relatives only, particularly when the stroke occurs at a younger age, usually less that age 70. Thus, if the parent died from a stroke at age 90, the implication is longevity, not heightened stroke risk for the patient in the office.
A variety of structural vascular and heart conditions are associated with strokes, including patent foramen ovale, aortic stenosis, cardiomyopathy, previous heart attack with scarring of the heart muscles, fibromuscular dysplasia, and different forms of inflammatory blood vessel conditions called vasculitides (singl., vasculitis) among others. Obviously, treatments, though not cures, are offered for these problems.
Occurrence of a stroke or TIA is associated with a high risk of future stroke. Within 5 years, the risk of recurrence is 20-40%, depending on the study that you read. TIAs are serious warning signs of an impending stroke. Up to 40 percent of people who experience a TIA are expected at some time later to have a stroke.
Therefore, after a first CVA or TIA, the patients and their families must concentrate not just on rehabilitation and recovery, but must consider how medical treatments, surgery, and lifestyle changes can help reduce the risk of recurrence.
Lifestyle Risk Factor
Smoking tobacco doubles the risk of stroke due to effects on atherosclerosis of the arteries and increased blood pressure.
And, by the way, cigarette smoking causes so many other health issues than stroke. Recall, respiratory failure, cancer (not just of the lungs), and premature ageing of the skin, with many wrinkles, already at age 40.
Although mild use of alcohol has been associated with lower risk of stroke, daily use of larger amounts of alcohol increases the risk for stroke. It is difficult to say whether some types of alcohol are better than others; arguments have been made for occasional use of red wine, which contains the chemical resveratrol. It has proven difficult to define excess alcohol use. Usually doctors give the advice that 2 - 3 drinks daily is TOO much and is associated with various health risks, in addition to stroke, - but that 1 - 2 drinks are fine. Tolerance is less in women and in people with less body weight.
Obesity and excess weight puts a strain on the entire circulatory system. Obesity also makes people more likely to have high cholesterol, high blood pressure and diabetes, - all of which can increase the risk of stroke. Obstructive sleep apnea of the obese patient is associated with increased risk of stroke, - but also headaches, memory problems and diminished attention.
Adopting healthy eating habits and increasing physical activity can help reduce stroke risk. Numerous studies have demonstrated that daily physical exercise, - even walking for 30 min (at home on a treadmill in front of the TV)- , is associated with lesser risk of stroke, heart attack, but also of memory loss, and movement abnormalities from Parkinson’s disease. The correct diet is important, though hard to define. The so-called Mediterranean diet may be a safe choice, - with vegetables, fruit, fish, lean meat, but restrained on carbohydrates.
Treatment and Prevention of Stroke
Clot? Not!
Antiplatelet and anticoagulant therapies are at the heart of preventing recurrent strokes. Although neither antiplatelet nor anticoagulant drugs can break up a clot (that’s a job for tPA and other clot busters being tested), both types of drugs are effective in keeping a clot from forming or stopping the growth of one. A lot of antiplatelets and anticoagulants are available to stroke survivors, and it helps to understand them.
Antiplatelet Medications
Blood platelets are actually fragments of cells – meaning they don’t contain all the necessary cellular equipment. When a person gets a cut or scratch, platelets release thromboxane, a chemical that signals other platelets to “help out.” Without the release of thromboxane, the platelets won’t come together, no clot will form, and the cut will continue to bleed. If you have a wound, thromboxane is an indispensable self-sealing material; but if you’re a stroke survivor, thromboxane’s ability to round up “help” to form a blood clot becomes potentially life-threatening.
Antiplatelet agents include aspirin, clopidogrel (Plavix), dipyridamole (Aggrenox is extended-release dipyridamole with a low dose of aspirin). They work by inhibiting the production of thromboxane. Aspirin is highly recommended for preventing a first stroke, but it and other antiplatelets also have an important role in preventing recurrent strokes.
According to a statement by the American Heart Association, taking aspirin within two days of an ischemic stroke reduces the severity of the stroke. In some cases, it prevents death. For long-term prevention, antiplatelet therapy is recommended primarily for people who have had a transient ischemic attack (TIA or “mini” stroke) or acute ischemic stroke.
Despite the potential benefits, antiplatelet therapy is not for everyone. People with a history of liver or kidney disease, gastrointestinal disease or peptic ulcers, uncontrolled high blood pressure, bleeding disorders and sometimes asthma may not be able to take aspirin or may require special dosage adjustments.
Anticoagulant Medications
While antiplatelets keep clots from forming by inhibiting the production of thromboxane, anticoagulants target clotting factors, which are other agents that are crucial to the blood-clotting process. Clotting factors are proteins made in the liver. These proteins can’t be created in the liver without Vitamin K – a common vitamin found in cabbage, cauliflower, spinach and other leafy green vegetables. Anticoagulants, such as warfarin (Coumadin), dabigatran (Pradaxa), heparin, and enoxaparin (Lovenox), slow clot formation by competing with Vitamin K. This inhibits the circulation of certain clotting factors with the exotic names of factors II, VII, IX and X.
Anticoagulants are considered more aggressive drugs than antiplatelets. They are recommended primarily for people with atrial fibrillation and certain types of implanted mechanical heart valves. More than 2 million Americans have atrial fibrillation (AF), a rhythmic disorder of the heart where the atria quivers instead of beats. As a result, not all of the blood is pumped out of the heart, allowing pools to collect in the heart chamber; clots may form and thus cause embolic stroke (see above). The American Heart Association recommends that most AF patients over age 65 receive some sort of anticoagulant therapy.
Anticoagulants are generally recommended only for patients with strokes caused by clots originating in the heart. Anticoagulants tend to be more expensive and carry a higher risk of serious side effects, including bruising and skin rash and bleeding in the brain, stomach and intestines. Patients that have unsteady gait with falls or who are confused or demented are at higher risk of complications from these medications. When used as directed, however, anticoagulants have proven very effective for AF patients. Although the potential risks seem severe, the life-saving effects give the drugs a bright upside.
Other people who may benefit from anticoagulant therapy for stroke prevention are those with blood that clots easily. The indications for use of anticoagulants have changed the last decade. Thus, patients with intracranial arterial blockages and patients with a series of recurring strokes are no longer “advanced” from antiplatelet to anticoagulant medications since there appears to be no benefits, just increased complications.
In comparison to antiplatelets, anticoagulants tend to be affected more by other drugs, vitamins and even certain foods, making anticoagulant therapy somewhat troublesome for stroke survivors. Because warfarin competes with Vitamin K, patients taking it should consult their doctors about possible dietary restrictions, as even some vegetables might cause an imbalance if eaten in excess. Many prescription drugs interact with warfarin to advance or weaken its effect.
Anticoagulant therapy requires regular blood tests to ensure the correct drug dose. A weak dosage increases the risk of stroke and heart attack, but too much may cause bleeding.
Combinations of Medications
Given the many benefits of antiplatelet and anticoagulant therapies, it seems logical that a combination of the two might magnify the positive effects. However, the combination of low-dose warfarin and low-dose aspirin is no more effective than aspirin by itself. Major bleeding episodes occurred nearly twice as often in the combination-therapy patients compared with the aspirin-only patients. Nevertheless, some patients may be asked by their cardiologist or neurologist to add a low dose aspirin to the anticoagulant.
Because of its low cost, availability and effectiveness, aspirin is the most prescribed and used drug in antiplatelet therapy. Aspirin plus extended-release dipyridamole is found more effective in secondary stroke prevention than aspirin alone. The combination of aspirin and clopidogrel is reserved for some patients after implantation of vascular stents and for a short time period after acute stroke or myocardial infarction.
The BEST Medication
Anticoagulants and antiplatelets should not be thought of in terms of one therapy being superior to the other. Because all strokes and stroke survivors are unique, secondary prevention must be tailored to the needs of the survivor. Many issues must be considered by the physician and the specific patient: overall efficacy, side-effect profile, nature of the patient’s stroke, and history of other underlying diseases (such as, cardiac disease, gastrointestinal bleeding, drug allergy and drug sensitivities), as well as cost.
Other Medications: “statins”
The use of cholesterol medications, “statins”, reduces risk of first stroke and heart attack. Such drugs also reduce risk of recurring ischemic stroke. The specific numbers on the blood test’s lipid profile is often less important; however, very abnormal results requires more aggressive treatment. Some patients do not tolerated statins due to renal or liver disease. Sometimes, muscle pains can be a side effect. Niacin or gemfibrozil can be added to a statin with when there is a low level of HDL cholesterol.
Supplementation with beta-carotene, fish oil, omega-3 fatty acids, CoQ 10, vitamin E, vitamin C or vitamin B does not appear to be effective in primary or secondary stroke prevention.
Other Medications: anti-hypertensives
Lower blood pressure is associated with fewer strokes. Prevention of recurring stroke includes close attention to and lowering of the blood pressure.
People with hypertension will live longer, if the blood pressure is well-controlled. After a stroke, many patients even with NORMAL blood pressure will be started on a heart medication, most often an ACE inhibitor (angiotensin converting enzyme inhibitor, f.ex., ramipril). Patients, but also physicians, have been reluctant to accept the benefits of using such medications along with a statin when the cholesterol is “normal” and when there is no hypertension.
Other Medications: diabetic drugs
Tight glucose control in diabetic patients reduces vascular complications, including stroke, particularly lacunar infarctions from small blood vessels (see above). Therefore, the diabetic patient should be compliant with the diabetic diet but should be treated with oral hypoglycemic drugs and/or insulin.
Summary of Treatment
The PROTECT program was designed to integrate proven secondary stroke prevention measures into the standard stroke care provided during acute hospital stay, with initiation and maintenance of the following goals for all patients with ischemic stroke (Ovbiagele B, Saver JL, Fredieu A, et al., PROTECT: a coordinated stroke treatment program to prevent recurrent thromboembolic events. Neurology, 2004; 63,1217)
· Antithrombotic therapy
· Statin therapy
· Angiotensin converting enzyme inhibitor or angiotensin
receptor blocker therapy
· Thiazide diuretic therapy
· Smoking cessation advice and referral to a formal cessation program
· American Heart Association diet
· Exercise counseling
· Stroke education, including knowledge of stroke warning signs
· Awareness of need to call 911 in case of cerebrovascular event
· Awareness of individual's risk factors
Implementation of this program was associated with a substantial increase in treatment utilization at the time of hospital discharge compared with conventional care.
Gold Achievement Award for Acute Stroke Care:
Dr. Rosenkilde cares for acute stroke patients at Northern Westchester Hospital (http://www.nwhc.net/home). In 2011, the hospital was recognized with a Gold Achievement Award for the "Get With The Guidelines" Excellence in Stroke Care program.
NWH received the American Heart Association/American Stroke Association’s Get With the Guidelines®-Stroke Gold Plus Quality Achievement Award, which recognizes the hospital for commitment and success in implementing excellent care for stroke patients, according to evidence-based guidelines. To receive the award, NWH achieved 85 percent or higher adherence to all Get With The Guidelines-Stroke Quality Achievement indicators for two or more consecutive 12-month intervals and achieved 75 percent or higher compliance with six of ten Get With The Guidelines-Stroke Quality Measures, which are reporting initiatives to measure quality of care. These measures include aggressive use of medications, such as tPA, antithrombotics, anticoagulation therapy, DVT prophylaxis, lipid-lowering drugs, and smoking cessation, all aimed at reducing death and disability and improving the lives of patients who have had a stroke.
Specifically the measures include
Percent of ischemic stroke or TIA patients who receive antithrombotic medication (e.g., warfarin, aspirin, other antiplatelet drug) within 48 hours of hospitalization.
Percent of ischemic stroke or TIA patients discharged on antithrombotics.
Percent of ischemic stroke or TIA patients with atrial fibrillation who are discharged on anticoagulation therapy (warfarin/Coumadin or heparin/heparinoids) unless an absolute or relative contraindication.
Percent of patients at risk for DVT who received DVT prophylaxis by the second hospital day.
Percent of ischemic stroke or TIA patients with LDL > or = 100 mg/dL OR on cholesterol reducer prior to admission who are discharged on cholesterol-reducing drugs.
Percent of smokers who receive smoking cessation advice or medication (e.g., Nicoderm or Zyban) at discharge.
Adapted from "Clot? Not!," Stroke Connection Magazine, July/August 2003 (Science update May 2008), from American Stroke Association, and from National Stroke Association.
http://www.stroke.org
