Heart disease is a broad term that includes several more specific heart conditions. The most common heart condition in the United States is coronary heart disease, which can lead to heart attack and other serious conditions.
CHD is the most common type of heart disease. CHD occurs when the coronary arteries, that supply blood to the heart muscle, become hardened and narrowed due to the plaque buildup. The plaque buildup and the narrowing and hardening of the arteries is called atherosclerosis. Plaques are a mixture of fatty substances including cholesterol and other lipids. Blood flow and oxygen supply to the heart can be reduced or even fully blocked with a growing plaque. Plaques may also rupture and cause blood clots that block arteries.
CHD can lead to a heart attack. Angina can also occur. Angina is chest pain or discomfort that occurs when the heart muscle is not getting enough blood. Over time, CHD can weaken the heart muscle and lead to heart failure, a serious problem where the heart cannot pump blood the way that it should. Also, irregular heart beats, called arrhythmias, can develop.
The most common symptom of CHD is angina. In some people the first sign of CHD is a heart attack. Doctors can assess a patient's risk status by checking several factors, including blood pressure, blood cholesterol and glucose, history of heart disease, and other factors. Doctors can perform several tests to assess CHD in patients who are at high risk or have symptoms. These may include one or more of these tests:
- ECG or EKG (electrocardiogram), which measures the electrical function and the rate and regularity of your heartbeat.
- Echocardiogram, which creates a picture of the heart.
- Exercise stress test, to measure how well the heart pumps at greater than usual workloads when it needs more oxygen.
- Chest x-ray, a picture of the organs and structures inside the chest.
- Cardiac catheterization, a thin, flexible tube is passed through an artery in the groin or arm to reach the coronary arteries. The tube lets your doctor check the inside of your arteries to see if there is any blockage. Your doctor also can measure the pressure and blood flow in the heart's chambers, collect blood samples from the heart, and examine the arteries of the heart by x-ray.
- Coronary angiography, which is usually performed along with cardiac catheterization. A dye is injected through the catheter into the coronary arteries. The doctor can then take an x-ray to see the flow of blood through the heart and check for blockages.
For persons with CHD, treatment will involve addressing those factors that put them at risk for CHD and heart attack. The doctor may recommend lifestyle changes to help reduce risk. Medicines and medical treatments may be needed. Medicines are available to treat high blood cholesterol, high blood pressure, irregular heart beats, blood flow, and other potential problems. Some advanced treatments and surgical procedures may be used to help restore blood flow to the heart muscle.
In principle, all people can take steps to lower their personal risk of heart disease and heart attack by addressing their risk factors. People who already have heart disease especially need to control their risk factors.
A heart attack is also called a myocardial infarction. If the blood supply to the heart is severely reduced or completely blocked, heart muscle cells may not receive enough oxygen and begin to die. The more time that passes without treatment to restore blood flow, the greater the damage to the heart. This damage can cause irregular heart rhythms or even sudden cardiac arrest or stopping of the heart beat. Death can result. Coronary artery disease is the chief underlying cause of a heart attack. A less common cause of a heart attack is a severe spasm of a coronary artery that reduces the blood supply to the heart.
When a person is having a heart attack, emergency care is needed that may include cardiopulmonary resuscitation (CPR), electrical shock (called defibrillation), and other advanced emergency medical care. Emergency medical personnel and doctors can quickly perform emergency treatment and transport the person to the hospital. Bystanders might also be trained to perform CPR and to use an automated external defibrillator, if one is available, until emergency medical personnel arrive. Once at the hospital, doctors can perform several tests to quickly determine if the person is having or has had a heart attack and the best course of action to restore blood flow.
Because a heart attack is a medical emergency, it is important to recognize the signs and symptoms of a heart attack and to act immediately by calling 9-1-1. A person's chance of surviving a heart attack is increased the sooner emergency treatment is administered.
A heart attack survivor may have a damaged heart that affects the heart rhythm, pumping action, and blood circulation. This puts heart attack victims at greater risk of having another heart attack or other events such as a stroke, kidney problems, and peripheral arterial problems. Cardiac rehabilitation is usually recommended for heart attack survivors after the emergency event has stabilized. Cardiac rehabilitation guides the patient to make changes that can help improve cardiovascular fitness and quality of life. These changes may include dietary changes, physical activity, smoking cessation, and other issues such as medication schedules and stress management. Heart attack survivors should seek their doctor's advice about daily activities such as returning to work, driving, physical and sexual activity, and air travel.