What is a heart attack?
A heart attack, or myocardial infarction, is a life-threatening condition in which the heart tissue does not receive enough oxygen. This lack of oxygen causes serious damage (infarction) to the heart muscle (myocardium) and its ability to function effectively.
Coronary artery disease, more commonly referred to as heart disease, is the most common cause of heart attack and the leading cause of death for both men and women in the United States, according to the Centers for Disease Control and Prevention (Source: CDC).
The heart is a muscle that requires a steady supply of oxygen in order for it to pump blood effectively to the rest of body. Oxygen is supplied to the heart by blood that flows through the coronary arteries. Heart attacks are most commonly due to the buildup of plaque on the coronary artery walls (atherosclerosis). Atherosclerosis can lead to the formation of a blood clot that blocks blood flow to the heart.
The area of the heart that is damaged in a heart attack and the severity of a heart attack vary depending on which coronary artery is blocked, how long the blockage lasts, and other factors. Damage to the heart can become permanent within minutes and result in the death of the affected heart tissue (myocardial necrosis or infarction) and death.
Angina is a type of chest pain that occurs when the heart is not getting enough oxygen. Having angina may mean that you are at increased risk for a future heart attack or that a heart attack may occur soon.
A heart attack is an immediately life-threatening condition that can rapidly lead to cardiac arrest and death. Immediate emergency heart attack treatment best minimizes the risk of these and other serious complications, such as heart failure and disability.
Seek immediate medical care (call 911) if you, or someone you are with, have heart attack symptoms, such as chest pain and difficulty breathing, which may be combined with dizziness, sweating, fainting and anxiety.
What are the symptoms of a heart attack?
Symptoms of a heart attack can differ depending on the area or areas of the heart affected and individual factors. The classic heart attack symptom is crushing chest pain. The nature of chest pain can vary greatly between individuals and may be described as tightness, squeezing, pressure, or fullness in the chest. Chest pain may also radiate to the shoulders, back, neck, jaw or arms.
Not all people who have a heart attack experience chest pain. In some cases, people may not have any symptoms. In other cases, symptoms may be mild or vague and include weakness, fatigue, dizziness, backache, or a feeling of indigestion. Women with myocardial infarction more often experience nausea rather than chest pain.
Serious symptoms that might indicate a life-threatening condition
Heart attack is a life-threatening condition. Seek immediate medical care (call 911) if you, or someone you are with, have any of these symptoms:
Bluish coloration of the lips or fingernails combined with pale skin
Change in level of consciousness or alertness, such as passing out or unresponsiveness
Extreme sweating (diaphoresis)
Fatigue with chest pain
Loss of pulse
Nausea and vomiting associated with chest pain
Pain in the shoulders, back, neck, jaw or arms that radiates from the chest or occurs by itself
Sudden, unexplained anxiety and restlessness
What causes a heart attack?
Heart attacks are most commonly caused by a buildup of plaque and inflammation in the coronary arteries. This is called atherosclerosis. Atherosclerosis narrows the coronary arteries, reducing the amount of oxygen-rich blood that reaches the heart muscle. This can result in angina, a type of serious chest pain. Angina is an important warning sign that the heart may be starving for oxygen.
Arteries narrowed by atherosclerosis are more likely to develop blood clots that completely block blood flow to the heart muscle, resulting in a heart attack.
What are the risk factors for a heart attack?
Heart attack risk factors increase your chances of having a myocardial infarction. They include:
- African American, Hispanic American, or American Indian ancestry
- Age older than 45 years
- High cholesterol (dyslipidemia)
- Excessive alcohol consumption
- Family history of a heart attack at an early age
- Long-term stress
- Male gender
- Sedentary lifestyle
Having high levels of certain substances in the body, which can be seen on blood tests, is associated with increased risk for heart attack. These include:
- High cholesterol, which can lead to atherosclerosis
- High C-reactive protein level, which reflects inflammation
- High homocysteine level, which may damage artery walls and increase the risk of developing clots that can lead to heart attack and stroke
Reducing your risk of heart attack
Not all people who are at risk will have a heart attack, and not all people who have a heart attack have risk factors. You can reduce your risk of heart attack by:
Eating a diet that is low in saturated fat and high in fiber, whole grains, and fruits and vegetables
Limiting alcohol consumption to no more than one drink per day for women and two drinks per day for men
Maintaining a healthy weight
Participating in a regular exercise program
Reducing excessive stress
Seeking regular medical care and following your treatment plan for such conditions as high cholesterol, hypertension, and diabetes
How is a heart attack treated?
If diagnosed early, some heart attacks can be successfully treated before the development of permanent heart damage and complications, such as heart failure and cardiac arrest. Heart attack treatment plans use a multifaceted approach and are individualized to the type and severity of your heart attack; your risk factors, lifestyle, and medical history; and other diseases and conditions you may have.
Typical treatments for a heart attack include hospitalization with monitoring in the intensive care unit, medications, supplemental oxygen, stabilization of vital signs, and, possibly, surgical procedures.
General treatments for a heart attack
General care of a heart attack includes:
Intensive monitoring and stabilization of heart rhythm and vital signs, which in some cases may require cardiopulmonary resuscitation (CPR) and advanced life support measures, such as intubation and mechanical ventilation to support breathing
Monitoring your heart rate and rhythm with a continuous electrocardiogram (known as an EKG or ECG) and blood tests to determine the presence or extent of heart damage
Regular follow-up care after discharge from the hospital, which is very important to help monitor your treatment and progress, and to promptly address any problems or complications
Supplemental oxygen to increase the amount of oxygen that is delivered to the heart tissue and the rest of the body
Medications used to treat a heart attack
A variety of medications may be used to treat a heart attack including:
ACE inhibitors (ramipril, lisinopril, enalapril or captopril) to lower blood pressure and help prevent heart failure
Aspirin to help prevent new blood clots
Heparin to help prevent new blood clots
Morphine to reduce pain and anxiety and lower the amount of oxygen the heart needs
Nitroglycerine to help widen narrow coronary arteries
Thrombolytic (clot-dissolving) drugs to break up and dissolve the clot that is causing the heart attack. Thrombolytic drugs are most effective if given within three hours of the onset of chest pain.
Surgical treatments for a heart attack
In some cases, a surgical procedure may be recommended to treat a heart attack:
Angioplasty and stent placement. In this procedure, the artery is widened using a balloon device, and usually a stent is placed in the artery to keep it open.
Coronary artery bypass. In this surgery, new graft arteries are placed to bypass the blocked coronary artery or arteries. Blood flow is then redirected through healthy new graft arteries to the affected heart tissues.
Implantation of defibrillator/pacemaker device to provide effective heart beat following myocardial infarction.
Other treatments for a heart attack
Other treatments and therapies that may be recommended as part of a complete treatment program for a heart attack include:
Cardiac rehabilitation and physical therapy to help strengthen your body, reduce complications, increase alertness, reduce fatigue, improve your overall health, and enhance your ability to function in everyday activities
Complementary or alternative treatments, such as acupuncture, massage therapy, and yoga, to help reduce stress, increase flexibility, and improve well-being. Complementary treatments are not meant to substitute for full medical care. Be sure to notify your doctor if you are consuming nutritional supplements or homeopathic (nonprescription) remedies as they may interact with the prescribed medical therapy.
Palliative care to improve the overall quality of life for families and patients with serious diseases
What are the possible complications of a heart attack?
Complications of a heart attack are life threatening. When the heart is damaged by a heart attack, it becomes weak and is unable to pump blood effectively throughout the body. This is called heart failure.
Damage to the heart caused by a heart attack can also trigger life-threatening abnormalities in heart rhythm (cardiac arrhythmias). Certain cardiac arrhythmias, such as ventricular tachycardia and ventricular fibrillation, can make the heart completely ineffective at pumping blood. These cardiac arrhythmias can lead to cardiac arrest (when the heart stops beating) and death within minutes.
Heart attack can also lead to the development of clots that lodge in other areas of the body, which can cause a stroke. Heart attack can also result in serious, permanent disability.
You can help minimize the risk of serious complications of a heart attack by following the treatment plan you and your health care professional design specifically for you. Complications of a heart attack include: