Introduction
Coronary artery disease (CAD), also called coronary heart disease (CHD) and atherosclerotic heart disease (ASHD), is caused by a thickening of the walls of the arteries that supply blood and oxygen to the heart. The thickened arteries cause the blood vessels to become narrow, which can lead to the restriction of flow of blood to the heart. CAD can lead to heart damage or heart attack. CAD is the leading cause of death for men and women in the United States according to the American Heart Association. Treatment of CAD may involve lifestyle changes, medications, interventional procedures, and surgery.
Anatomy
The heart has several large arteries and veins connected to it that branch out and become smaller as they travel throughout your body. Arteries are blood vessels that carry oxygenated blood away from your heart. The aorta is the largest blood vessel in your body. The aorta carries all the blood that is pumped out of your heart, and through its many branches, distributes blood to all of the organs throughout the body. Two coronary arteries branch from the aorta, which supply the heart with oxygenated blood and nutrients to keep it healthy. Veins are vessels that carry blood from your body and lungs back to your heart.
Causes
CAD results when the walls of the arteries that supply the heart with oxygen and blood thicken. The thickened walls cause a narrowed space for blood to flow through. The normally elastic walls of the artery become hard from plaque formation and are unable to promote blood flow. These thickened plaques can rupture which leads to even greater blockage. Over time, heart cell death and heart muscle damage can lead to angina, shortness of breath, heart attack, and sudden death.
Symptoms
Some people may have CAD without any noticeable symptoms. For others, the symptoms may be very apparent. CAD may cause angina or chest pain. The chest pain most typically occurs under the breastbone or in the left chest, abdomen, or back. It may feel like squeezing, heaviness, or intermittent sharp pain. It may radiate to your neck or arms. The pain may or may not occur or get worse with exercise or emotion and may or may not get better with rest or nitroglycerin medication. CAD may cause shortness of breath, which may be a sign of congestive heart failure. Along with shortness of breath, your ankles and feet may swell if the heart’s pumping mechanism is weak.
In some cases, heart attack is the first sign of CAD. Heart attack chest pain is usually severe and not relieved by rest or nitroglycerin. If you suspect you are having a heart attack, call for an ambulance, and chew an aspirin if one is nearby.
Diagnosis
A doctor can begin to diagnose CAD by reviewing your medical history and conducting a physical examination, blood tests, and cardiovascular tests. You doctor will check your pulse and blood pressure. Heart studies and imaging tests will be performed to learn more about the structure and function of your heart and cardiovascular system.
There are a variety of heart assessments and imaging studies.
An electrocardiogram (ECG) is used to record the heart’s electrical activity. An ECG may be repeated over several hours.
An exercise stress test, also called a cardiac stress test or treadmill test, involves monitoring your ECG and blood pressure while you walk on a treadmill.
An echocardiogram uses sound waves to produce an image on a monitor and can also be used to perform a stress test.
Nuclear ventriculography (MUGA or RNV) involves using a safe radioisotope injection to produce an image of the heart with special scanners. Electron-beam computed tomography (EBCT) evaluates how much calcium is in the plaque in the arteries.
A coronary angiography uses a dye and X-rays to show an image of the heart.
Treatment
The treatment that you receive for CAD depends on your symptoms and the severity of your condition. Treatment of CAD may involve lifestyle changes, medications, interventional procedures, and surgery. Lifestyle changes may involve attaining and maintaining a healthy weight, blood pressure, cholesterol level, and blood sugar level. It can be helpful to exercise regularly and eat a diet that avoids salt, saturated fats, cholesterol, and trans fats. It is very important to quit smoking.
There are a variety of medications that work in different ways to help treat CAD and the factors that contribute to it. Such medications may work to lower cholesterol, thin blood, decrease heart rates, lower blood pressure, and stop chest pain. Some medications may work to improve blood flow by opening the blood vessels and relaxing the arteries.
Coronary angioplasty (balloon PTCA), stenting, athrectomy, and radiation implant or brachytherapy are interventional procedures that may be used to treat CAD. A coronary angioplasty is a procedure that opens blocked coronary arteries. A stent may be inserted to ensure that the coronary artery remains open. Coronary brachytherapy delivers radiation into the coronary arteries. It is usually reserved for people that have had difficulties with stents.
Minimally invasive heart surgery may be used to treat CAD. Coronary artery bypass surgery (CABG) involves taking a blood vessel from another part of the body to create a detour around a clogged artery to restore the blood flow to the heart. Blood vessels are commonly taken from the leg and surgically attached to the coronary artery. It may be necessary to have bypass surgery on one or more coronary arteries.
Prevention
You may prevent CAD by reducing the risk factors that you have control over including your weight, blood pressure, diabetes, cholesterol, and activity level. It is important to quit smoking. It can be helpful to exercise regularly and eat a heart healthy diet. Your doctor can refer you to a nutritionist if you need suggestions for meal planning or eating guidelines.
Am I at Risk
Risk factors may increase your likelihood of developing CAD, although some people that develop the condition do not have any risk factors.
Risk factors for CAD:
- Family history of CAD
- Men over the age of 45 and women over the age of 55
- Cigarette smoking
- Obesity
- High blood sugar levels from diabetes
- High blood pressure
- High cholesterol
- People that are physically inactive
- Higher than normal inflammation markers found by blood testing
Complications
CAD can result in angina, heart attack, and sudden death. If you experience the symptoms of a heart attack you should call an ambulance. Some heart attacks occur suddenly and intensely. Others may start out slowly. A heart attack can cause chest pain, pressure, squeezing, fullness, or pain that lasts for more than a few minutes. The chest discomfort may come and go. It may feel like you have bad indigestion, a tight band around your chest, or that “an elephant is sitting on your chest.” You may experience pain that radiates to your jaws, neck, shoulder, teeth, arms, back, or abdomen. A heart attack can cause shortness of breath, nausea, vomiting, lightheadedness, and a cold sweat.
Women and men may experience different symptoms of a heart attack. For both men and women, chest discomfort is the most common symptom of a heart attack. However, women are more likely than men to experience atypical symptoms such as back or jaw pain, overwhelming fatigue, dizziness, nausea, vomiting, and shortness of breath.