Coronary heart disease (CHD) is a narrowing of the small blood vessels that supply blood and oxygen to the heart. CHD is also called coronary artery disease.
Complications of Coronary Artery Disease
If coronary artery disease (CAD) is not diagnosed and treated, it can lead to serious heart conditions, including the following:
Heart failure occurs when some areas of your heart are chronically deprived of oxygen and nutrients because of reduced blood flow. Your heart may become too weak to pump enough blood to meet your body's needs. This can cause symptoms of shortness of breath and fatigue that increases with activity. Heart failure can lead to swelling in your feet, ankles, legs, and abdomen.
Heart attack can occur if plaque breaks free of artery walls and a blood clot forms, blocking one of the coronary arteries. The lack of blood flow to your heart may cause permanent damage to your heart muscle. The amount of permanent damage depends in part on how quickly you're treated after a heart attack. Heart attacks can be mild to severe.
A stroke is an interruption of the blood supply to any part of the brain. Blood clots, which can be caused by a buildup of plaque in the arteries, are dangerous because they can cut off the healthy blood supply to the brain, causing a stroke.
Sudden cardiac arrest is when the heart suddenly stops beating and pumping blood to the rest of your body. It's caused by a problem within the heart's electrical system that results in an abnormal heart rhythm. Immediate treatment with a defibrillator, which sends an electric shock to the heart to try to return it to a normal rhythm, can save lives.
Causes of Coronary Artery Disease
Coronary heart disease is caused by any problem with the coronary arteries that keeps the heart from getting enough oxygen- and nutrient-rich blood. The most common cause is atherosclerosis which occurs when fatty material and a substance called plaque builds up on the walls of your arteries. This causes them to get narrow. As the coronary arteries narrow, blood flow to the heart can slow down or stop, causing chest pain (stable angina), shortness of breath, heart attack, and other symptoms. Lack of sufficient blood is called ischemia, so coronary heart disease is sometimes called ischemic heart disease.
Signs & Symptoms of Coronary Artery Disease
Symptoms may be very noticeable, but sometimes you can have the disease and not have any symptoms. Chest pain or discomfort (angina) is the most common symptom. You feel this pain when the heart is not getting enough blood or oxygen. How bad the pain is varies from person to person. It may feel heavy or like someone is squeezing your heart. You feel it under your breast bone (sternum), but also in your neck, arms, stomach, or upper back. The pain usually occurs with activity or emotion, and goes away with rest or a medicine called nitroglycerin. Other symptoms include shortness of breath and fatigue with activity (exertion). Women, elderly people, and people with diabetes are more likely to have symptoms other than chest pain, such as:
Shortness of breath
Diagnosis of Coronary Artery Disease
An electrocardiogram (ECG) detects abnormal electrical cardiac charges. In someone who has had heart damage, the electrical signals that keep the heart beating change as they pass through damaged tissue. This can be detected and measured on an ECG.
An exercise electrocardiogram (or stress test) checks your heart for changes during periods of activity, and it can also show if the coronary arteries are too narrow. An exercise stress test is performed on a treadmill or a stationary bicycle while hooked up to an ECG. A thalliumscan allows imaging of blood flow in the heart during exercise. This involves injecting a very small dose of radioactive substance into the bloodstream, which is followed through the heart by a special camera.
With angina, abnormalities in the ECG may only occur while the person is having an angina attack. Some people have "silent angina," where even an attack brings no symptoms. To detect this, you may be asked to wear a monitor for 24 hours. The ECG tape is analysed for irregularities, and then compared with a detailed diary, in which you record your daily activities and any unusual symptoms.
Coronary angiography (or arteriography) is a test used to explore the coronary arteries. A fine tube (catheter) is put into an artery of an arm or leg and passed through the tube into the arteries of the heart. The heart and blood vessels are injected with contrast dye, which is then filmed with an X-ray while the heart pumps. The picture that is seen, called an angiogram or arteriogram, will show problems such as a narrowing or blockage caused by atherosclerosis.
Treatments of Coronary Artery Disease
Therapeutic options for coronary artery disease today are based on three principles:
If you suspect you're having a heart attack, immediately call your local emergency number. If you don't have access to emergency medical services, have someone drive you to the nearest hospital. Drive yourself only as a last resort. If you have risk factors for coronary artery disease — such as high blood pressure, high cholesterol, diabetes or obesity — talk to your doctor. He or she may want to test you for the condition, especially if you have signs or symptoms of narrowed arteries. Even if you don't have evidence of coronary artery disease, your doctor may recommend aggressive treatment of your risk factors. Early diagnosis and treatment may stop progression of coronary artery disease and help prevent a heart attack.