A stroke (or brain attack) is cardiovascular disease that occurs when a blood vessel that delivers oxygenated blood and nutrients to the brain either ruptures or is blocked by a blood clot. As result, part of the brain is unable to receive the oxygenated blood it needs, and brain cells begin to die. Understanding your risk factors for and the symptoms of a stroke are critical because obtaining immediate treatment can be the difference between life and death.

Strokes are classified into two categories. Nearly 90 percent of strokes are ischemic strokes or strokes that are created by a clot blocking an artery in the brain. When the clot is formed at the site of the stroke and doesn't travel to the vessel it blocks, it's called a thrombus. When the clot travels, it's referred to as an embolism. The second and less common type of stroke is a hemorrhagic or bleeding stroke.

A clot blocking an artery in the brain produces an ischemic stroke. The causes for this type of stroke include:

• Atherosclerosis: Plaque on the vessel walls can block the flow of blood or cause abnormal blood flow that creates clots (very similar mechanism that causes a heart attack).
• Heart disorder or device (e.g. mechanical heart valve): Even a diseased native heart valve, such as in rheumatic mitral stenosis, can promote the development of a clot that can be transported from the pumping heart to the brain. Arrhythmias, such as atrial fibrillation, can cause blood clots to form in the chambers of the heart. A clot formed in the heart can then be expelled into the circulation of the brain.

A hemorrhagic or bleeding stroke is caused by blood vessels that weaken and burst. Experts believe that the primary cause of this type of stroke is related to a defect in the blood vessels of the brain that causes them to be more fragile than normal and predisposed to rupture.

Risk factors
Understanding your risk factors for stroke can prevent a stroke and help you obtain faster treatment if you have one. A risk factor is a characteristic or lifestyle habit that increases your chances for developing a particular health problem. Uncontrollable risk factors are those characteristics that you cannot change or manage, such as age, gender, ethnicity and family history. Likewise, controllable risk factors are manageable characteristics and lifestyle habits that you can control. For example, you can modify your weight and tobacco use. You can control elevated blood pressure with medications, diet restrictions and regular aerobic exercise.

Uncontrollable stroke risk factors:

• Heart arrhythmia: Take prescribed anticoagulant medications and follow-up with your physician regularly.
• Congenital heart malformation or disease: Take prescribed medications, follow lifestyle recommendations, and follow-up with your physician regularly.
• Increasing age: Your risk increases as you age. Understand the symptoms.
• Gender: Men are at an increased risk for stroke compared to women, although women are responsible for more than half of the deaths attributed to stroke.
• Heredity: Know your family history.
• Race: African Americans and Hispanics' risk for stroke is higher than Caucasians'.
• History of stroke: If you've had one stroke, your risk for a second is higher.

Controllable stroke risk factors:

• High blood pressure (hypertension): Take control with prescribed medication, diet restrictions and exercise.
• Atherosclerosis (especially plaque that causes coronary artery disease, peripheral vascular disease and/or carotid artery disease): Take control with lifestyle changes (including diet and exercise) and prescribed medications.
• Poor cholesterol levels (High LDL and low HDL cholesterol): Take control with prescribed medication, diet restrictions and exercise.
• Tobacco use/smoking: Quit!!!
• Excessive alcohol use: Drink alcoholic beverages in moderation or abstain altogether.
• Obesity, excess weight and inactive lifestyle: Take control with diet, a prescribed exercise program and guidance from your physician and nutritionist.
• Diabetes: More than 65 percent of people with diabetes die from heart disease or stroke, but you can change the statistics by carefully managing your blood sugar and other controllable risk factors.

Recognizing the symptoms of a stroke and seeking immediate medical attention are essential to surviving a stroke and avoiding the most debilitating effects. In fact, with ischemic stroke (the most common type of stroke caused by a blood clot), you have to be diagnosed and treated within a critical three hour window when the most effective, lifesaving and disability-reducing therapies, such as thrombolytic therapy, can be administered. Thrombolytics are highly effective because they actually dissolve the clot, but they have to be administered within three hours of the onset of stroke.

So if you or someone you know experience any of these symptoms, seek IMMEDIATE medical attention:

• Slurred speech, difficulty speaking, confusion
• Dizziness, vertigo and unexplained sudden falls
• Weakness or numbness of the arm, leg or faces, especially when it occurs on one side of the body
• Loss of vision or blurred vision, especially in only one eye
• Excruciating headache with no known cause

If you or someone you know experiences the symptoms of a stroke, call 911 immediately. Emergency Medical Services can best transport you to the hospital quickly and safely. At the hospital, the medical team will conduct a thorough exam that may include specific tests to determine any neurologic, sensor and motor deficiencies to try to pinpoint the area of the brain affected by the stroke. Additional tests may include:

• CT or MRI of the head
• EKG
• Echocardiogram
• Carotid duplex
• Blood work
• Holter monitor (a small EKG that you wear over a long period of time that records your heart rate throughout the day or days)
• Head angiography