This overview is a sample of the type of information available to you at Griffin Hospital's Community Health Resource Center. It is not intended to replace your physician's instructions in the management of your health problems, but to better inform you about a particular illness and alert you to the availability of other materials. If you have a question about any piece of information presented in theses fact sheets, please call your physician, or stop by the Community Health Resource Center at your convenience.
A heart attack occurs when a part of the heart does not get the oxygen it needs for a prolonged period of time, causing permanent damage to that part of the heart muscle. Because the heart is responsible for pumping blood through the body, damage to the heart muscle can cause serious problems with the circulation of blood through the body.
The heart normally gets its oxygen from three primary blood vessels (called coronary arteries) and many smaller branches of these vessels. These blood vessels bring oxygenated blood (blood which has passed through the lungs) to the heart muscle. When the heart does not get enough oxygen to a certain area, this part of the heart muscle will die. Depending on the area affected, this can cause problems with the speed and rhythm of the heartbeat or the strength of the pumping.
There are several reasons that can cause the heart to not get the oxygen it needs. The most common reason is because of narrowing of the blood vessels, called atherosclerosis. Atherosclerosis occurs when fat deposits form on the inside wall of the arteries, causing them to thicken and harden, narrowing the passageways. These narrowed arteries prevent enough blood and oxygen from reaching the heart, especially during periods of increased activity, when the body needs more oxygen than when resting.
Other causes can be a clot in one of the coronary vessels which blocks blood from getting through, severe muscle spasms of the coronary arteries, very low blood pressure, or irregular heartbeats. A rupture of plaque or of a weak area in the artery wall can also prevent the heart from getting the oxygen it needs.
A heart attack can occur very suddenly or can come on gradually. Heart attacks often occur during or after exertion, stress, or eating a heavy meal when the oxygen demands are higher than usual, putting extra strain on the heart. A heart attack is also called a “coronary” or myocardial infarction (MI).
WHAT CAUSES A HEART ATTACK?
Heart attacks are usually caused by atherosclerosis, but can be caused by any underlying condition or event which prevents oxygen from getting to the heart and results in damage to the heart cells. Things which cause the heart to beat irregularly or erratically, such as other heart conditions, or drugs such as cocaine can cause a heart attack.
Because atherosclerosis can be caused by a diet high in fat or cholesterol, this type of diet can increase the chance of a heart attack. Other factors which can contribute to your risk of having a heart attack are things which put extra demands on the heart muscle, such as lack of exercise, extreme exhaustion, obesity, or high levels of sustained stress.
WHO HAS A HEART ATTACK?
If there is heart disease in your family, your likelihood of having a heart attack is increased. Your risk is also increased if you have high blood pressure or smoke. Men have a much higher rate of heart attacks than pre-menopausal women. But after a woman goes through menopause, her risk increases and equals that of men. It is thought that women's hormone levels prior to menopause protect them from heart attacks.
Smokers are three times as likely as non-smokers to have a heart attack. Diabetics also are at increased risk.
Heart attacks can occur in both men and women of any age, but are most common in individuals between 50 and 70.
WHAT ARE THE SYMPTOMS OF A HEART ATTACK?
The most common symptoms are intense pain, pressure, or a squeezing sensation in the chest area. The symptoms may also be felt in the jaw, neck, left arm and back areas. Sometimes the only symptom is shortness of breath. Other symptoms are heavy sweating, feelings of faintness, lightheadedness, nausea, and vomiting.
Some individuals have several of the symptoms; others only have one. Most of the time, the symptoms come on during activities which increase the work on the heart and subside with rest.
Heart attack symptoms can last for a few minutes or much longer. Any pain in the chest or upper abdomen that lasts more than a few minutes could be a heart attack. For some, the symptoms can be very much like those of indigestion. Some heart attacks can be "silent," with no pain or symptoms. It is important to pay attention to any of these symptoms and get immediate medical assistance.
DIAGNOSING A HEART ATTACK
An EKG (electrocardiogram) will be done to look at the electrical activity of your heart. After a heart attack, certain patterns are seen on the EKG. Blood tests can also be done to look for certain chemicals in your blood that are released by the heart when it is damaged.
Other tests may be done to determine what type of heart attack you have had and/or what damage has occurred. An angiogram (also called a cardiac catherization) may be performed. This test involves a dye being injected into the coronary arteries while x-rays are taken to follow the route of the dye. This test can show the size and shape of the heart and the condition of its vessels and valves. An echocardiogram is another test that provides pictures of the heart to see how well it is pumping.
TREATMENT FOR A HEART ATTACK
Prompt medical care in the first hours after an attack increases the chance of survival. If you have chest pain regularly, and your nitroglycerin does not relieve the pain, get medical attention right away. Some physicians feel that taking an aspirin as soon as you think you may be having a heart attack decreases the severity of the attack and improves survival rates. If you think you are having a heart attack, don't wait for symptoms to get worse. Call an ambulance or have someone take you to the nearest emergency room. Do not drive yourself to the hospital.
Treatment is usually started right away within the first one to three hours of your admission to the hospital. The first thing medical personnel will do is to try to restore flow to your heart before damage is done. You should sit or lie down, and will be given oxygen. An IV (tube to give you fluids and medication) will be put in your vein. You will be given various medicines to relieve the pain and increase blood flow to the heart. You may be taken to a special unit of the hospital where equipment to monitor your heart is available.
Depending on what is causing your heart attack, different medications may be given. If your heart attack is due to a clot, you may receive thrombolytic agents to dissolve the clots. You may also be given anticoagulant drugs to help keep your blood thin.
A vasodilator (medication which opens up the blood vessels) such as nitroglycerin may be given to relax the coronary arteries or other blood vessels to reduce the workload of the heart.
Other medications that help the heart pump more effectively such as digitalis may be prescribed. The use of medications called beta blockers help the heart recover after a heart attack. Your physician will determine which medications are most appropriate for your condition.
After a heart attack, the heart muscle needs to rest and should not be stressed by any kind of activity. As you recover, you can start walking for a longer amount of time and start regaining your strength.
If you need pain relief, nitroglycerin can be taken either under the tongue in pill form or sprayed onto the tongue for quick absorption into the blood. Severe pain may be treated with other medications.
After a heart attack, the rhythm of the heart's pumping can be disturbed so that it beats too rapidly, too slowly, or irregularly. You will be closely monitored.
If there is damage to the heart muscle, the heart may have trouble pumping blood through the body. This is often treated with certain medications such as digitalis, which increases the strength of the pumping action, and diuretics, which reduces the extra water in the body. Other medicines can also be taken to relax the walls of blood vessels so less pressure and work are needed for the heart to pump blood through the body.
Procedures such as an angioplasty or coronary artery bypass may be considered if a blockage is found that puts you at risk of a future heart attack.
WHAT YOU CAN DO
The most important thing you can do is to prevent another heart attack. The following lifestyle changes have been shown to decrease the risk of another attack:
It is important to see your doctor for regular follow-up visits. Studies show that continuing certain medications indefinitely can be beneficial in preventing future heart attacks. Your doctor may want to do periodic testing or lab work to monitor how your heart is doing. You should gradually rebuild your strength and endurance. Over time, your body can develop new branches of blood vessels to make up for the areas which are damaged or blocked.
COPING
An acute, painful illness can be very stressful. It usually takes anywhere from a few weeks to a few months to return to your normal activity. After you return home, you may go through a period of readjustment during which you will wonder about your condition. You may worry about how a heart condition will affect your sex life or how much exercise or work will be safe. You and your family may find it helpful to talk to others who have had similar experiences. Community organizations can provide support and information.
Please note that this information is intended to give you a general overview of the topic. It is not intended to replace advice or instruction of a health professional. We recommend that you consult your physician, nurse, or qualified health professional regarding the information in this publication. © 1994 Planetree, Inc. Reproduction of this material in any form is limited to license agreement.
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