CORONNARY ARTERY DISEASE

Causes

Damage or injury to the inner layer of a coronary artery initiates CAD, sometimes as early as childhood. The damage may be caused by various factors, including:

• Smoking
• High blood pressure
• High cholesterol
• Diabetes
• Radiation therapy to the chest, as used for certain types of cancer

Damage to the inner wall of an artery leads to fatty deposits (plaques) made of cholesterol and other cellular waste products to accumulate at the site of injury in a process called atherosclerosis. Rupture of the surface of these plaques causes blood cells called platelets to clump at the site to try to repair the artery. Heart attack can occur due to this dumping.

SYMPTOMS

Narrowed coronary arteries are unable to supply enough oxygen-rich blood to your heart — especially when it’s beating hard, such as during exercise. Initially, the decreased blood flow may not cause any coronary artery disease symptoms. But, you may develop coronary artery disease symptoms as the plaques continue to build up in your coronary arteries. The symptoms are:

• Chest pain (angina). It is typically a feeling of pressure or tightness in your chest, as if someone were standing on your chest. This symptom, called as angina, is usually triggered by physical or emotional stress. It abolishes within minutes after stopping the stressful activity. This pain may be fleeting or sharp and noticed in the abdomen, back or arm in some people, especially women.
• Shortness of breath. You may develop shortness of breath or extreme fatigue with exertion if your heart can’t pump enough blood to meet your body’s needs.
• Heart attack. Heart attack ensues if a coronary artery becomes completely blocked. Heart attack classically presents with crushing pressure in your chest and pain in your shoulder or arm, sometimes with shortness of breath and sweating. Less typical signs and symptoms are present in women. Sometimes a heart attack occurs without any apparent signs or symptoms.

Diagnosis

Upon presentation to doctor, a medical history will be taken, a physical exam will be conducted routine blood tests will be ordered. Doctor may suggest one or more diagnostic tests as well, including:

• Electrocardiogram (ECG). It is an electrical recording of the signals as they travel through your heart. Evidence of a previous heart attack can be revealed by an ECG. If the signs and symptoms of your atherosclerosis is more evident during exercise, your doctor may ask you to walk on a treadmill or ride a stationary bike during an ECG.
• Blood tests. Blood is tested for elevation of certain heart enzymes that slowly leak out into your blood if your heart has been damaged by a heart attack.
• Abnormal heart rhythms (arrhythmias). Electrical “short circuits” can develop if your heart muscle is damaged from a heart attack. These can cause abnormal heart rhythms, some of which can be serious, even fatal.
• Stress test. Stress test is also an exercise stress test. It is used to gather information about how well your heart works during physical activity. By doing exercise on bike or treadmill your heart pump harder and faster than it does during most daily activities. Testing of the heart during and after exercise can reveal problems within your heart that might not be noticeable otherwise. The procedure usually involves walking on a treadmill or riding a stationary bike while your heart rhythm and blood pressure and breathing are monitored. In some types of stress tests, pictures will be taken of your heart, such as during a stress echocardiogram (ultrasound) or nuclear stress test. In patients who are unable to exercise due to some or other reason, a medication that mimics the effect of exercise on heart is used to make it pump harder.
• Chest X-ray. Images of your heart and lungs is displayed by this test. Also, other conditions can be looked into that might explain your symptoms and to see if you have an enlarged heart.
• Echocardiogram. It is a type of ultrasound examination of your heart to produce images of the heart. These images are seen by the doctor to identify heart attack-related problems, including whether there are areas of your heart not getting enough blood or heart muscle that’s been damaged by poor blood flow. Sometimes, an echocardiogram is performed during a stress test.
• Nuclear stress test. This test is performed to assess blood flow to your heart muscle at rest and during stress. It is similar to a routine stress test but uses a radioactive substance.
• Coronary angiography. Narrowing or blockade in coronary arteries can be revealed by this test. The test involves injecting a liquid dye into the arteries of your heart through a long, thin tube (catheter) that’s fed through an artery, usually in your leg, to the arteries in your heart. The arteries become visible on X-ray, as the dye fills your arteries. Any area of blockage can then be revealed.
• Cardiac computerized tomography (CT) scan. During performance of this test, you lie on a table inside a doughnut-shaped machine. Inside the machine there is an X-ray tube which rotates around your body and collects images of your heart and chest. These images can show if any of your heart’s arteries are narrowed or if your heart is enlarged.
• Cardiac MRI: In this test, the patient is made to lie on a table inside a long tube-like machine that produces a magnetic field. The magnetic field aligns atomic particles in some of your cells. Signals are produced when radio waves are broadcast toward these aligned particles. These signals vary according to the type of tissue they are. The signals create images of your heart.

Complications

Treatment