Coronary Heart Disease

Coronary heart disease (CHD) is the most common form of heart disease and the leading cause of death for Americans. About 12.6 million Americans suffer from CHD, which often results in a heart attack. About 1.1 million Americans suffer a heart attack each year, and about 515,000 of these heart attacks are fatal.

 

Fortunately, CHD can be prevented or controlled. This fact sheet gives an overview of CHD and its prevention, diagnosis, and treatment. It describes the steps that you can take to protect your heart-health.

 

 

That blood flow can be reduced by a process called atherosclerosis, in which plaques or fatty substances build up inside the walls of blood vessels. The plaques attract blood components, which stick to the inside surface of the vessel walls. Atherosclerosis can affect many blood vessels, causing them to narrow and harden. It develops over many years and can begin early, even in childhood.

 

In CHD, atherosclerosis affects the coronary arteries. The fatty buildup, or plaque, can break open and lead to the formation of a blood clot. The clot covers the site of the rupture, also reducing blood flow. Eventually, the clot becomes firm. The process of fatty buildup, plaque rupture, and clot formation recurs, progressively narrowing the arteries. Less and less blood reaches the heart muscle.

 

When too little blood reaches a part of the body, the condition is called ischemia. When this occurs with the heart, it's called cardiac ischemia. If the blood supply is nearly or completely, and abruptly, cut off, a heart attack results and cells in the heart muscle that do not receive enough oxygen begin to die. The more time that passes without treatment to restore blood flow, the greater the damage to the heart. Because heart cells cannot be replaced, the cell loss is permanent.

 

 

Certain behaviors and conditions increase the risk that someone will develop CHD (see Box below). They also can increase the chance that CHD, if already present, will worsen. They are called "risk factors" and while some cannot be modified, most can.

 

 

 

Symptoms of CHD vary. Some people feel no discomfort, while others have chest pain or shortness of breath. Sometimes the first symptom of CHD is a heart attack or cardiac arrest (a sudden, abrupt loss of heart function).

 

Chest pain also can vary in its occurrence. It happens when the blood flow to the heart is critically reduced and does not match the demands placed on the heart. Called angina, the pain can be mild and intermittent, or more pronounced and steady. It can be severe enough to make normal everyday activities difficult. The same inadequate blood supply also may cause no symptoms, a condition called silent ischemia.

 

Often, particularly in men, angina is felt behind the breastbone and may radiate up the left arm or neck. It may also be felt in the shoulder, elbows, jaw, or back. Angina is usually brought on by exercise, lasts 2 to 5 minutes, does not change with breathing, and is eased by rest.

 

Women may get a less typical form of angina that feels like shortness of breath or indigestion, and can linger or occur in a different location than behind the breastbone. This less typical form may not be brought on by exertion or be eased by rest. In fact, it may occur only at rest.

 

A person who has any symptoms should talk with his or her doctor. Without treatment, the symptoms may return, worsen, become unstable, or progress to a heart attack.

 

 

Those with CHD should talk with their doctor about the symptoms of a heart attack and the appropriate steps to take to get emergency care. The key to surviving a heart attack is fast action. Learn the heart attack warning signs and if you or someone else experiences any of them, call 9-1-1 immediately. Fast treatment is critical; treatments to restore blood flow to the heart are most effective if given within the hour of the start of symptoms. The sooner treatment is begun, the greater the chance for survival and a full recovery.

 

 

Chest discomfort is the most common warning sign and is the same for men and women. However, women are somewhat more likely than men to have some of the other common symptoms, particularly shortness of breath, nausea and vomiting, and back or jaw pain. Also, women tend to be about 10 years older than men when they have a heart attack and often have other conditions as well, such as diabetes, high blood pressure, and congestive heart failure. Fast treatment is vital.

 

 

Six key steps can help prevent or control CHD: stop smoking cigarettes; lower high blood pressure; reduce high blood cholesterol; lose extra weight; become physically active; and manage diabetes.

 

Cigarette smoking. There is no safe way to smoke. Although low-tar and low-nicotine cigarettes may somewhat reduce the risk for lung cancer, they do not lessen the risk for CHD. In fact, smoking accelerates atherosclerosis. It also increases the risk for stroke.

 

The risk for CHD increases along with the number of cigarettes smoked daily. Quitting sharply lowers the risk, even in the first year and no matter what a person's age. Quitting also reduces the risk for a second heart attack in those who have already had one.

 

High blood pressure. Also known as hypertension, high blood pressure usually has no symptoms. Once developed, it typically lasts a lifetime. If uncontrolled, it can lead to heart and kidney diseases, and stroke.

 

Blood pressure is given as two numbers - the systolic pressure over the diastolic pressure - and both are important. A measurement of 140/90 mmHg (millimeters of mercury) or above is called high blood pressure, although if either number is high, that is also hypertension. A healthy blood pressure is around 120/80.

 

Lifestyle steps often can prevent or control high blood pressure: lose excess weight, become physically active, follow a healthy eating plan including foods lower in salt and sodium, and limit alcohol intake. Some of these steps are the same as those needed to reduce the risk for CHD and are discussed in more detail in other sections of this web site.

 

High blood cholesterol. Cholesterol is a soft, waxy substance involved in normal cell function. Normally, the body makes all the cholesterol it needs. Excess saturated fat and cholesterol in the diet cause the fatty buildup in blood vessels, which contributes to atherosclerosis.

 

Overweight/obesity. About 65 percent of American adults are overweight or obese. Being overweight or obese increases the risk not only for heart disease, but also for other conditions, including stroke, gallbladder disease, arthritis, and breast, colon, and other cancers.

 

Physical activity. Physical activity is one of the best ways to help prevent and control CHD. It can lower Low Density Lipoprotein (LDL), or "bad cholesterol," which in large quantities leads to a buildup of cholesterol in the arteries. Physical activity also raises High Density Lipoprotein (HDL), or "good cholesterol," which carries cholesterol from various parts of your body to your liver for removal from the body. High HDL reduces your risk of getting heart disease, while high LDL increases your risk of getting heart disease. Another benefit of physical activity is that it can help lowers blood pressure for those who are overweight.

 

Diabetes. Diabetes mellitus affects more than 17 million Americans. It damages blood vessels, including the coronary arteries of the heart. Up to 75 percent of people with diabetes develop heart and blood vessel diseases. Diabetes also can lead to stroke, kidney failure, and other problems.

 

Diabetes occurs when the body is not able to use sugar as it should for growth and energy. The body gets sugar when it changes food into glucose (a form of sugar). Insulin, a hormone made in the pancreas, is needed for the glucose to be taken up and used by the body. In diabetes, the body cannot use the glucose in the blood because either the pancreas cannot make enough insulin or the insulin that is available is not effective.

 

Symptoms of diabetes include increased thirst and urination (including at night), weight loss, and blurred vision, hunger, fatigue, frequent infections, and slow healing of wounds or sores.