What is coronary heart disease?
LAST UPDATED: Dec 01, 2019
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Coronary heart disease (or coronary artery disease) is a condition where the oxygen and blood flow to your heart is restricted or reduced because plaque build-up narrows the arteries that feed it. Coronary heart disease is the leading cause of death in the United States, according to the National Heart, Lung, and Blood Institute (NIH, n.d.).
What causes coronary heart disease?
Coronary heart disease (CHD) is due to a build-up of plaque along the walls of the coronary arteries, the blood vessels that supply oxygen-rich blood to the heart. Plaque is a fatty deposit made of cholesterol and other cell waste products; as the plaque deposit gets thicker, the central channel (lumen) of the blood vessels (where the blood flows) gets narrower. The narrow lumen results in less blood (and oxygen) getting through to the heart cells; this is called atherosclerosis. Atherosclerosis may start as early as childhood and can progress to coronary artery disease as you get older. While the exact causes of atherosclerosis are not known, one theory is that when the inner lining of the blood vessels (the endothelium) gets damaged, plaques are attracted to accumulate at the site of injury. Injuries to vessel endothelium can be due to diabetes, high cholesterol, high blood pressure, and smoking; smoking, in particular, makes the plaques more likely to form and grow quickly. If the plaque deposit ruptures, it will attract clotting factors, like platelets, in an attempt to repair the rupture; these platelets clump up to make a clot, which can then block off the entire artery leading to a heart attack.
Signs and symptoms of coronary heart disease
As the coronary arteries get narrower, less oxygen-rich blood can get to the heart. In the early stages, the plaque build-up is minimal and most people don’t experience any symptoms. However, as the build-up increases and less blood reaches the heart, you may start to experience symptoms, including:
Angina (chest pain): This can feel like pressure (like a heavy weight on your chest), squeezing, burning, or tightness; it can occur at rest, with physical activity, or with emotional stress. Typically the discomfort starts in your chest and radiates to your arms, neck, jaw, shoulder, or back. Some people report that their chest pain feels like indigestion.
Shortness of breath, especially with exercise
Women, however, can have a different presentation of their coronary heart disease. Men often report the classic chest pain with exertion that stops when they rest. Sometimes women can also experience this, but they are more likely to have no symptoms from their coronary artery disease than men. When they do have symptoms, women more often report things like tightness or pressure in the chest, nausea, abdominal pain, vomiting, fatigue, and dizziness.
Complications of coronary heart disease
If coronary heart disease is left untreated, it can lead to other medical conditions including:
Stable angina: This is chest pain or tightness that occurs when you make your heart work harder, like climbing stairs or walking for several minutes, and lasts for about five minutes; it resolves when you rest or take angina medications. Stable angina is relatively predictable and usually feels the same each time.
Unstable angina: This is a more dangerous form of angina and is a medical emergency, as it can be a sign of an impending heart attack. Unstable angina can occur at rest, can be more severe and last longer than your prior episodes, and may not improve with rest or taking your medications. If you experience this, you need to call 911 immediately. Unstable angina is a type of acute coronary syndrome, a situation where a coronary artery is suddenly blocked.
Heart attack: Another type of acute coronary syndrome is a heart attack. If a coronary artery gets completely blocked off, like when a plaque ruptures and a blood clot forms, the heart cells fed by that particular coronary artery die due to lack of oxygen (myocardial infarction). The classic symptoms of a heart attack include sudden chest pain, or crushing pressure in your chest, and pain along your left arm; sometimes, other symptoms like shortness of breath and sweating also occur. In women, heart attacks may present with chest pain, but they are more likely than men to have different symptoms, like shortness of breath, nausea or vomiting, and back or jaw pain (AHA, 2015). The diagnosis of a heart attack in women can be delayed due to these non-classic symptoms.
Stroke: If a plaque breaks off and travels to the brain, it can get lodged in a brain blood vessel and block the blood flow to part of the brain. When this happens, those brain cells fed by that vessel die; this is called a stroke.
Heart failure: People with long-term coronary artery disease have narrow, but not blocked arteries feeding their heart tissue. Over time, the heart tissue becomes weaker because it is not getting enough oxygen and nutrients; alternatively, if you have had a heart attack due to your coronary artery disease, then parts of the heart have been damaged. Either way, the heart is no longer able to pump blood to the rest of your body the way that it should; this is called heart failure.
Arrhythmias: Damage to heart tissue from an inadequate blood supply can lead to problems with the electrical system of the heart; this leads to abnormal heartbeats, also called arrhythmias.
Risk factors for coronary heart disease
The risk factors for coronary artery can be divided into three categories: risks that you can not change, risks that you can treat, and other factors that contribute to coronary artery disease.
Risks that you cannot control:
Age: As you get older, your arteries harden and are more likely to narrow; most people who die from coronary heart disease are over 65 years of age (AHA, 2016).
Gender: Men are more likely to get coronary artery disease, especially after age 45. After age 55, the risk for women is similar to that of men.
Genetics: People with a family history of coronary heart disease, especially if a close relative developed it at a young age, are at higher risk. This is especially true if your father or brother was diagnosed with coronary heart disease before age 55 or if your mother or sister developed it before age 65 (NIH, n.d.).
Race: African Americans, Mexican-Americans, American Indians, and native Hawaiians all have a higher risk of coronary heart disease than Caucasians.
Risks that you can modify include:
Smoking: Tobacco smoke can damage your blood vessels and lead to the development of atherosclerosis and coronary artery disease. Exposure to secondhand smoke also increases the risk of developing heart disease.
High blood pressure: Uncontrolled high blood pressure makes your heart work more and contributes to the hardening of your arteries; this increases your risk of coronary artery disease.
High cholesterol: High levels of cholesterol in the blood increase your risk of coronary artery disease. Elevated low-density lipoprotein (LDL, or “bad” cholesterol) and low levels of high-density lipoprotein (HDL, or “good” cholesterol) contribute to the development of atherosclerosis.
High triglycerides: This is another type of fat in your blood; when the levels are high, you are at an increased risk of coronary artery disease.
Diabetes: Even if your sugar levels are under control, diabetes still increases your risk of coronary artery disease; the risk is even higher if your diabetes is uncontrolled. According to the American Heart Association (AHA), approximately 68% of people with diabetes who are over 65 years old die from some form of heart disease; in that same group, 16% die from stroke (AHA, 2016).
Obesity or being overweight: People who are obese or overweight, especially if they have excess body fat around their waist, have a higher risk of coronary heart disease.
Sedentary lifestyle: People who don’t exercise have a higher risk of developing coronary heart disease, as well as some of its risk factors, like obesity.
Stress: There is a relationship between stress and coronary heart disease.
Diet: Eating a heart-healthy diet high in fruits and vegetables can decrease your risk of obesity and heart disease.
Excessive alcohol consumption: Drinking too much alcohol (more than two drinks per day for men or one drink per day for women) can contribute to heart disease by increasing your blood pressure and your triglycerides.
Sleep apnea: In this condition, you repeatedly stop and start breathing while you sleep, causing drops in your blood oxygen levels. These sudden drops can increase your blood pressure, putting a strain on the cardiovascular system and possibly leading to coronary artery disease.
How to diagnose coronary heart disease
After discussing your medical history, eating habits, exercise routines, etc. your healthcare provider may decide to order additional tests to see if you have coronary heart disease. These tests include:
Electrocardiogram (ECG or EKG): This is a standard test that can be performed in the office. It looks at the electrical activity of the heart to see if you are having a heart attack or have had one in the past.
Echocardiogram: This test uses sound waves to create a picture of your heart and visualize how well the different chambers are pumping. If parts of the heart are not pumping well, it can be a sign of a previous heart attack or indicate areas where the heart muscle is sick from lack of oxygen; this could be due to coronary artery disease.
Cardiac angiography (catheterization): In this minimally invasive procedure, a thin tube is inserted into a blood vessel in your groin or arm and guided into your heart. Once inside, a special dye is injected into your blood vessels to visualize any narrowed or blocked arteries. If found, the arteries can be opened back up by inserting a balloon, via the catheter, into the blocked artery to open it up and a mesh stent placed to keep it from closing off again.
Exercise stress test: You are asked to exercise (or given medicine to make your heart beat faster to simulate exercise) and pictures are taken of your heart to see how your heart functions under stress.
Cardiac CT scan: A CT scan is taken of your heart to detect or evaluate any coronary artery disease.
Treatment of coronary heart disease
Treatment of coronary artery disease typically involves lifestyle changes, plus medications or procedures as needed.
Adopting a heart-healthy lifestyle includes:
Eating a diet low in sodium and saturated fat and rich in fruits and vegetables
Keeping a healthy weight
Exercising several times a week
Sometimes behavioral changes are not enough and medications need to be added to keep your heart healthy. Medicines that your provider may recommend:
In some people, more aggressive measures are needed in addition to medication and lifestyle changes. Sometimes, procedures to open or bypass your blocked coronary arteries are necessary to maintain your heart health.
One such procedure is percutaneous coronary intervention (PCI), formerly called angioplasty with stent placement. In this procedure, a blocked (or severely narrowed) coronary artery is opened via a balloon inserted through a catheter directly into the blocked artery. The balloon is inflated inside the artery, opening it up, and a stent is placed to hold the artery open; some stents release medication over time to also help keep the artery open and blood flowing.
Another option is a coronary artery bypass graft (CABG) surgery, a type of open-heart surgery. The surgeon takes a blood vessel from another part of the body and creates a new passageway (bypass) for blood to flow to the areas of the heart fed initially by the blocked artery.
How to prevent coronary heart disease
The best way to prevent coronary heart disease is to treat the risk factors for this condition. Most of the risk factors are related to overall heart health, like high cholesterol and diabetes, doing things to keep your heart healthy may also prevent coronary heart disease. Things you can do to improve your heart health include:
Heart-healthy diet: Eat a low salt, low saturated fat diet that is high in fruits and vegetables
Physical activity: Exercise several times a week
Treat existing heart disease (like high blood pressure, high cholesterol, or heart failure) and other medical conditions like diabetes as instructed by your provider
If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.
American Heart Association (AHA). (2015, July 31). Heart Attacks Symptoms in Women. Retrieved Dec. 1, 2019 from https://www.heart.org/en/health-topics/heart-attack/warning-signs-of-a-heart-attack/heart-attack-symptoms-in-women
American Heart Association (AHA). (2016, June 30). Understand Your Risks to Prevent a Heart Attack. Retrieved Dec. 1, 2019 from https://www.heart.org/en/health-topics/heart-attack/understand-your-risks-to-prevent-a-heart-attack
National Institutes of Health (NIH). (n.d.). National Heart, Lung, and Blood Institute - Ischemic Heart Disease. Retrieved Dec. 1, 2019 from https://www.nhlbi.nih.gov/health/coronary-heart-disease