Today, tomorrow, and every day this year, roughly 1,900 strokes will be suffered by people in the U.S. After heart disease and cancer, strokes are responsible for more American deaths than any other medical condition, but experts say much could be done to change this.

Guidelines released today by the American Stroke Association highlight some well-established and less well-known risk factors for stroke, as well as measures people can take to lower their risk. People are more aware of stroke than they used to be. But far too many people ignore or don't recognize the symptoms of stroke and delay seeking treatment.

Strokes happen when part of the brain loses its blood supply. This can happen in two major ways, as outlined below:

Ischemic Strokes
More than 80% of strokes occur when a blood vessel (an artery) in the brain or neck gets blocked by a blood clot. This is called an ischemic stroke. Typical strokes are ischemic and are due to clogged arteries.

Doctors further classify ischemic strokes by where the blood clot originated. When a clot forms in an artery, stays in place, and blocks the artery, it's called a thrombus -- and a person has a thrombotic stroke. More than half of ischemic strokes are thrombotic strokes.

Another mechanism of ischemic stroke is a clot arising from the heart: an embolism. That is a clot from one part of the body going to another. When these traveling clots wedge into a blood vessel leading to the brain, a person has an embolic stroke.

Hemorrhagic Strokes
Strokes also occur when an artery supplying blood to the brain bursts. These are hemorrhagic strokes.

Hemorrhagic strokes are also further classified by where they originate. When a hemorrhagic stroke happens inside the brain, it's called an intracerebral hemorrhage. When it happens in the subarachnoid space (between the brain and a lining surrounding it), it's called a subarachnoid hemorrhage.

The usual cause of intracerebral hemorrhage is high blood pressure. Another cause is an aneurysm -- a weak spot in the wall of the artery that balloons out. When these balloons pop, a person has a stroke. This is the usual cause of subarachnoid aneurysms.

Hemorrhagic stroke can be just as devastating as ischemic stroke. There are other types of bleeding that affect the brain. Subdural hematomas and epidural hematomas are bleeding just outside the brain. Usually caused by a head injury, these are technically not considered strokes. But they do compress the brain and can cause similar disabilities.

Symptoms of strokes can include, but are not limited to:

    Weakness or numbness in the face, arm, or leg n side of the body.
    Sudden, intense headache
    Dizziness or loss of balance or coordination -- especially when another warning sign is present
    Sudden blurry vision or loss of vision in one or both eyes.
    Trouble speaking or understanding simple phrases.

If you think you are having a stroke or someone around you is, call 911 immediately, not your doctor. If someone is having a stroke there is nothing that can be done in their doctor's office and there is nothing that patients can do at home. Time is critical, and the quicker a stroke victim gets to a hospital the better his or her chances of surviving and recovering. The brain likes blood and oxygen, and the longer it goes without them the lower the chances that they will fully recover.

Clot-busting drugs used to treat ischemic stroke (stroke from a blood clot) can only work if they are given within three hours of the onset of symptoms.

Obviously, a stroke is never a good thing. But some are worse than others. Severity depends on two things: the part of the brain affected and the size of the affected brain area.

The first distinction in stroke damage is the side of the brain affected. The left side is the dominant hemisphere, related to language function for most people. One of the things people fear the most is a stroke that leaves them unable to speak and to understand speech. When the stroke is on the right, usually patients are able to have normal conversations. There may be more subtle cognitive problems not immediately obvious, but usually right-side stroke patients can have a better recovery.

There is naturally a hole in the heart while you are developing. Usually, at birth, it closes. It is called PFO: patent foramen ovale. About 25% of the population has that without any symptoms involved.

But if a person with a PFO has a stroke -- and no other obvious risk for stroke -- doctors often assume that the hole is allowing tiny blood clots to pass into the circulation and causing stroke. It's a very controversial area, as there's no definitive proof that this really happens.

We have the technology to close the hole, but also the controversy over whether to do it.

Once a PFO is suspected of causing a stroke, doctors usually put the patient on blood thinners to prevent new clots from forming. Blood thinners (such as Coumadin) increase a person's risk of hemorrhagic stroke. So doctors sometimes decide to repair the hole in the heart so that a patient can stop taking these medicines.

For closing the hole, you thread a catheter through the right side of the heart. And at the end of the catheter is a collapsed umbrella like in a cocktail drink. The catheter is inserted into the hole itself, and the umbrella is deployed. That is a permanent closure of the hole that was there since birth.

Blood-thinning medications save people's lives. Though these important drugs can raise a person's hemorrhagic stroke risk, they also can cut ischemic stroke risk. And the drugs are an important part of treatment for atrial fibrillation, a life-threatening heart rhythm problem.

People shouldn't walk away thinking, 'I don't want to take my Coumadin,'.

Low birth weight was recognized for the first time as a possible risk factor for stroke, based on recent studies suggesting a doubling of risk among adults who weighed less than 5.5 pounds at birth compared with those who weighed 8.8 pounds or more. The reason for this is unclear, and this association does not mean that low birth weight causes stroke. Other well established, non-modifiable stroke risk factors include age, sex, race or ethnic background, and family history. Elderly people, men, blacks, and people with a family history of stroke tend to have a higher than average risk.

The guidelines call for very aggressive stroke screening and prevention efforts for children and adults with sickle cell disease. About 10% of children with sickle cell will have had a stroke by the time they reach adulthood.

Patients who know they are at risk for having a stroke tend to be more motivated to make lifestyle changes and take their medication than patients who are simply told they have cardiovascular disease.

Sleep-disordered breathing, such as in sleep apnea, also appears to increase stroke risk. This suspected link led to the recommendation that people with excessive daytime sleepiness and who may snore loudly each night be evaluated for the condition and get treatment if they have it

What's the best treatment for stroke? The real focus should be on prevention. People need to know their blood pressure, their cholesterol level, and whether they are prone to diabetes. People unfortunately often find out about these risks after having a stroke or heart attack. The treatments we give to prevent stroke are far more effective than the ones we give after a stroke. Being more active physically is far more effective at preventing stroke than blood thinners or fixing a hole in the heart.

Anyone worried about stroke should see their doctor, get evaluated for stroke risk, and make the needed changes in their lifestyle.

However, if a person has one of the five classic warning signs of stroke, they should immediately go to an emergency room. The sooner a diagnosis can be made and treatment started, the greater the chance for a favorable outcome.

All stroke survivors are recommended to see a neurologist for a full evaluation and individualized treatment.

Though stroke is certainly life threatening, survival is the rule, not the exception. The majority of people do survive strokes. And the majority of survivors get through it and regain much function.

Of course, recovering from stroke means hard work. It's called rehabilitation -- rehab for short. Rehab is considered an expected part of stroke recovery. It is tailored based on what is needed.

There are four basic kinds of rehab:
    Speech therapy helps those with trouble talking.
    Physical therapy means getting the limbs moving, increasing power, and relearning how to walk.
    Occupational therapy is based on relearning the skills needed for daily care -- for example, going up the stairs, putting one's clothes on, and using dining utensils.
    Cognitive therapy helps people who have lost the ability to speak or understand language.

Most people benefit from at least some kind of rehabilitation therapy following stroke.

The new report reiterated some well-known steps that people can take to lower their stroke risk, including:

    Knowing your blood pressure and keeping high blood pressure under control
    Not smoking and avoiding exposure to second-hand smoke
    Getting regular physical exercise
    Aggressively treating disorders that increase stroke risk, such as diabetes, irregular heartbeat, carotid artery disease, and heart failure
    Treating diabetes patients with statins to lower "bad" cholesterol
    Increasing potassium in the diet to at least 4.7 grams a day and reducing sodium intake to 2.3 grams or less to help lower blood pressure in people with hypertension
    A referral to be considered for genetic counselling for people with rare genetic causes of stroke

Other prevention efforts that may reduce stroke risk include:
    Limiting alcohol consumption to no more than two drinks a day if you are a man and one drink a day if you are a woman. Avoiding illicit drug use.
    Taking low-dose aspirin if you are a woman at high risk for stroke. Aspirin has been shown to reduce heart attack risk in men, but the stroke data are less conclusive. No one should take aspirin for prevention without first discussing it with their doctor, however.
    Postmenopausal hormone therapy should not be used for prevention of stroke.