Although their symptoms and effects can be similar, strokes and heart attacks are two different medical problems. Both are vascular events, meaning they involve the blood vessels, the arteries in particular. Both conditions can also lead to disability and death.
Heart attacks are almost always the result of progressive coronary artery disease (CAD). In CAD, the arteries that supply blood to the heart become choked with fatty deposits called plaque, which narrows and blocks arteries. The condition is called atherosclerosis. When pieces of plaque break free, blood clots can form, blocking the flow of blood to the heart. When that happens, the heart muscle does not get the oxygen and nutrients that it needs, and parts of the heart may become damaged or die. This is a heart attack, also known as myocardial infarction.
When the blood supply to the brain is interrupted, causing a part of the brain to die, it is called a stroke, or "brain attack." Stroke is similar to a heart attack, but it affects the blood vessels in the brain instead of the heart.
When the flow of blood to the brain is blocked by a clot, it's called an ischemic stroke. Another type of stroke, called a transient ischemic attack, is sometimes called a "mini stroke" and is caused by a temporary clot.
A hemorrhagic stroke happens when a blood vessel in the brain bursts and bleeds, depriving an area of the brain of blood and causing damage inside the brain. Hemorrhagic stroke are classified in two ways, defined by the type of blood vessel causing the damage. The most common — an aneurysm — occurs when an artery or ordinary blood vessel within the brain balloons, weakens, and bursts. In rare cases, an abnormal, tangled mass of blood vessels will form in the brain. This is called an arteriovenous malformation (AVM). Sometimes, one of the vessels within the AVM will burst, causing bleeding and compression in the brain.
Causes of heart attack and stroke
The causes for heart attack and stroke are similar, yet diverse. Both share many of the same risk factors, such as family history, obesity, smoking, lack of physical activity, high blood pressure, high cholesterol, diabetes, and vascular disease. But there are some differences, too:
Gender. Men tend to have more heart attacks, and have them at an earlier age, than women. But, while more men have strokes than women, women in all age groups are more likely to die from stroke.
Race. African-Americans have higher rates of CAD and more severe high blood pressure than whites. CAD is also more prominent in Mexican-Americans, American Indians, Alaska Natives, and Pacific Islanders, in part because of higher rates of obesity and diabetes, two other common risk factors for both heart attack and stroke.
Another risk factor for stroke is a transient ischemic attack (TIA), also called a "mini-stroke." TIAs produce the same symptoms as a stroke but don't cause lasting damage. A person who has had one or more TIAs is almost 10 times more likely to have a stroke, the American Stroke Association says. Consider a TIA a medical emergency and seek immediate medical help.
Reducing your risk
To reduce your risk for heart attack and stroke, it's important to control your risk factors. This means making healthy lifestyle choices:
Quit smoking if you smoke.
Eat a healthy diet.
Get plenty of exercise.
Control high blood pressure, diabetes, and cholesterol with medications, if necessary.
The American Heart Association recommends that you begin screening for heart and vascular disease by age 20. Screening includes measuring your blood pressure, body mass index (an assessment of your weight and height), waist circumference, and pulse rate at each regular health care visit, or at least every two years. If you are at normal risk, you should get a cholesterol profile every five years — more often if your risk is higher.