Angina

概述

Angina is a type of chest pain caused by reduced blood flow to the heart. Angina (an-JIE-nuh or AN-juh-nuh) is a symptom of coronary artery disease.

Angina, also called angina pectoris, is often described as squeezing, pressure, heaviness, tightness or pain in your chest. Some people with angina symptoms say angina feels like a vise squeezing their chest or a heavy weight lying on their chest. Angina may be a new pain that needs to be checked by a doctor, or recurring pain that goes away with treatment.

Although angina is relatively common, it can still be hard to distinguish from other types of chest pain, such as the discomfort of indigestion. If you have unexplained chest pain, seek medical attention right away.

症状

Angina symptoms include chest pain and discomfort, possibly described as pressure, squeezing, burning or fullness.

You may also have pain in your arms, neck, jaw, shoulder or back.

Other symptoms that you may have with angina include:

• Dizziness
• Fatigue
• Nausea
• Shortness of breath
• Sweating

These symptoms need to be evaluated immediately by a doctor who can determine whether you have stable angina, or unstable angina, which can be a precursor to a heart attack.

Stable angina is the most common form of angina. It usually happens when you exert yourself and goes away with rest. For example, pain that comes on when you're walking uphill or in the cold weather may be angina.

Characteristics of stable angina

• Develops when your heart works harder, such as when you exercise or climb stairs
• Can usually be predicted and the pain is usually similar to previous types of chest pain you've had
• Lasts a short time, perhaps five minutes or less
• Disappears sooner if you rest or use your angina medication

The severity, duration and type of angina can vary. New or different symptoms may signal a more dangerous form of angina (unstable angina) or a heart attack.

Characteristics of unstable angina (a medical emergency)

• Occurs even at rest
• Is a change in your usual pattern of angina
• Is unexpected
• Is usually more severe and lasts longer than stable angina, maybe 30 minutes or longer
• May not disappear with rest or use of angina medication
• Might signal a heart attack

There's another type of angina, called variant angina or Prinzmetal's angina. This type of angina is rarer. It's caused by a spasm in your heart's arteries that temporarily reduces blood flow.

Characteristics of variant angina (Prinzmetal's angina)

• Usually happens when you're resting
• Is often severe
• May be relieved by angina medication

Angina in women

Symptoms of angina in women can be different from angina symptoms that occur in men. These differences may lead to delays in seeking treatment. For example, chest pain is a common symptom in women with angina, but it may not be the only symptom or the most prevalent symptom for women. Women may also have symptoms such as:

• Nausea
• Shortness of breath
• Abdominal pain
• Discomfort in the neck, jaw or back
• Stabbing pain instead of chest pressure

When to see a doctor

If your chest pain lasts longer than a few minutes and doesn't go away when you rest or take your angina medications, it may be a sign you're having a heart attack. Call 911 or emergency medical help. Arrange for transportation. Only drive yourself to the hospital as a last resort.

If chest discomfort is a new symptom for you, it's important to see your doctor to find out what's causing your chest pain and to get proper treatment. If you've been diagnosed with stable angina and it gets worse or changes, seek medical attention immediately.

病因

Angina is caused by reduced blood flow to your heart muscle. Your blood carries oxygen, which your heart muscle needs to survive. When your heart muscle isn't getting enough oxygen, it causes a condition called ischemia.

The most common cause of reduced blood flow to your heart muscle is coronary artery disease (CAD). Your heart (coronary) arteries can become narrowed by fatty deposits called plaques. This is called atherosclerosis.

During times of low oxygen demand — when you're resting, for example — your heart muscle may still be able to function on the reduced amount of blood flow without triggering angina symptoms. But when you increase the demand for oxygen, such as when you exercise, angina can result.

• Stable angina. Stable angina is usually triggered by physical activity. When you climb stairs, exercise or walk, your heart demands more blood, but narrowed arteries slow down blood flow. Besides physical activity, other factors such as emotional stress, cold temperatures, heavy meals and smoking also can narrow arteries and trigger angina.

• Unstable angina. If fatty deposits (plaques) in a blood vessel rupture or a blood clot forms, it can quickly block or reduce flow through a narrowed artery. This can suddenly and severely decrease blood flow to your heart muscle. Unstable angina can also be caused by blood clots that block or partially block your heart's blood vessels.

  Unstable angina worsens and isn't relieved by rest or your usual medications. If the blood flow doesn't improve, your heart is starved of oxygen and a heart attack occurs. Unstable angina is dangerous and requires emergency treatment.

• Prinzmetal's angina. This type of angina is caused by a sudden spasm in a coronary artery, which temporarily narrows the artery. This narrowing reduces blood flow to your heart, causing severe chest pain. Prinzmetal's angina most often occurs at rest, typically overnight. Attacks tend to occur in clusters. Emotional stress, smoking, medications that tighten blood vessels (such as some migraine drugs) and use of the illegal drug cocaine may trigger Prinzmetal's angina.

风险因素

The following risk factors increase your risk of coronary artery disease and angina:

• Tobacco use. Chewing tobacco, smoking and long-term exposure to secondhand smoke damage the interior walls of arteries — including arteries to your heart — allowing deposits of cholesterol to collect and block blood flow.
• Diabetes. Diabetes increases the risk of coronary artery disease, which leads to angina and heart attacks by speeding up atherosclerosis and increasing your cholesterol levels.
• High blood pressure. Over time, high blood pressure damages arteries by accelerating hardening of the arteries.
• High blood cholesterol or triglyceride levels. Cholesterol is a major part of the deposits that can narrow arteries throughout your body, including those that supply your heart. A high level of low-density lipoprotein (LDL) cholesterol, also known as "bad" cholesterol, increases your risk of angina and heart attacks. A high level of triglycerides, a type of blood fat related to your diet, also is unhealthy.
• Family history of heart disease. If a family member has coronary artery disease or has had a heart attack, you're at a greater risk of developing angina.
• Older age. Men older than 45 and women older than 55 have a greater risk than do younger adults.
• Lack of exercise. An inactive lifestyle contributes to high cholesterol, high blood pressure, type 2 diabetes and obesity. However, it is important to talk with your doctor before starting an exercise program.
• Obesity. Obesity is linked with high blood cholesterol levels, high blood pressure and diabetes, all which increase your risk of angina and heart disease. If you're overweight, your heart has to work harder to supply blood to the body.
• Stress. Stress can increase your risk of angina and heart attacks. Too much stress, as well as anger, also can raise your blood pressure. Surges of hormones produced during stress can narrow your arteries and worsen angina.

并发症

The chest pain that occurs with angina can make doing some normal activities, such as walking, uncomfortable. However, the most dangerous complication is a heart attack.

Common signs and symptoms of a heart attack include:

• Pressure, fullness or a squeezing pain in the center of your chest that lasts for more than a few minutes
• Pain extending beyond your chest to your shoulder, arm, back, or even to your teeth and jaw
• Increasing episodes of chest pain
• Nausea and vomiting
• Prolonged pain in the upper abdomen
• Shortness of breath
• Sweating
• Fainting
• Impending sense of doom

If you have any of these symptoms, seek emergency medical attention immediately.

预防

You can help prevent angina by making the same lifestyle changes that might improve your symptoms if you already have angina. These include:

• Quitting smoking.
• Monitoring and controlling other health conditions, such as high blood pressure, high cholesterol and diabetes.
• Eating a healthy diet and maintaining a healthy weight.
• Increasing your physical activity after you get your doctor's OK. Aim for 150 minutes of moderate activity each week. Plus, it's recommended that you get 10 minutes of strength training twice a week and to stretch three times a week for five to 10 minutes each time.
• Reducing your stress level.
• Limiting alcohol consumption to two drinks or fewer a day for men, and one drink a day or less for women.
• Getting an annual flu shot to avoid heart complications from the virus.