Heart disease is a category of health conditions that can affect any part of the heart or the coronary arteries, the vessels that bring blood to the heart. The different types of heart disease are categorized based on the cause and the part of the heart that is affected. It’s common to have more than one type of heart disease, as some types of heart disease can directly cause another type. For example, hypertension (high blood pressure) makes the heart work harder and can cause atherosclerosis (a buildup of fatty plaques that narrow the arteries) and cardiomyopathy (heart muscle disease).

Read more about heart disease symptoms and treatments.

Normal Heart Anatomy and Function

Knowing a little about the anatomy of the heart and how it works will help you understand the different types of heart disease. The heart has four compartments called chambers: two atria (left and right) on top and two ventricles (left and right), one below each atrium. The right atrium receives oxygen-depleted blood from the body and moves it into the right ventricle, which pumps it into the lungs to receive fresh oxygen. The left atrium receives freshly oxygenated blood from the lungs and moves it into the left ventricle — the heart’s largest and strongest heart chamber — which pumps the blood around the body.

The heart has four valves — mitral, aortic, tricuspid, and pulmonary — that control the flow of blood between each chamber. The valves open to allow the blood to flow into the next chamber and snap shut to prevent backflow.

The heart’s rhythm and pace are controlled by collections of cells that produce electrical impulses. These cells coordinate the muscle contractions of the heart’s chambers. The sinoatrial (SA) node, the heart’s natural pacemaker, sends the electrical signals that make your heart beat. This electrical impulse travels through fibers from the SA node to the atrioventricular (AV) node in the lower heart chambers, ensuring that each chamber of the heart beats in a regular rhythm that allows sufficient blood flow.

The vascular system is made up of arteries, which carry blood away from the heart to all the tissues of the body, and veins, which bring blood back to the heart. The coronary arteries supply the heart itself with oxygen and nutrients.

Heart Disease Types

Heart disease can affect any part of the heart or cardiovascular system, including the blood vessels, heart valves, SA node, and heart muscle.

Blood Vessel Diseases

Diseases of the blood vessels, also called vascular diseases, are very common. Blood vessel disease does not usually cause symptoms until significant damage has occurred. Smoking, a diet high in saturated (animal) fats, lack of exercise, and inherited genetic changes are risk factors for vascular disease development.

High blood pressure, or hypertension, silently damages organs and makes the heart work harder. According to the Centers for Disease Control and Prevention (CDC), nearly half of adults in the U.S. have high blood pressure, and only about a quarter of those adults have their condition under control. High blood pressure contributes directly to the development of many other types of heart disease and raises the risk of stroke and heart attack.

Atherosclerosis is another vascular disease where cholesterol and fat form sticky plaques that build up on the walls of the arteries. This causes the arteries to narrow, raising blood pressure. Plaques can break off and block arteries, causing a heart attack or stroke.

Coronary artery disease (CAD) occurs when plaque builds up in the coronary arteries. CAD is the most common cardiovascular disease in the U.S. In CAD, the coronary arteries that supply the heart narrow and may become fully blocked. Many people with CAD are unaware they have developed the condition until they experience chest pain (angina) or a heart attack.

Peripheral artery disease (PAD) is caused by plaque buildup in arteries outside the heart, such as the arteries of the arms, legs, stomach, or head. It most commonly occurs in the arteries of the legs. PAD can result in blockages to the blood supply that prevent tissues from receiving blood. PAD can cause intense pain, tissue death (gangrene), stroke, or brain damage. It can be especially life-threatening if it develops in the head or neck arteries.

An aneurysm occurs when a weak spot in an artery wall bulges out. Aneurysms can occur in any artery. Some aneurysms are present at birth, while others are caused by lifestyle factors such as high blood pressure, high cholesterol, and smoking. A ruptured aneurysm is a life-threatening emergency.

Valvular Heart Problems

Heart valves can become stenotic (too rigid to open fully) or incompetent (too loose to close completely). A stenotic valve causes blood to back up because it cannot let enough blood through with each beat (stenosis), while an incompetent valve allows some blood to leak back into the previous chamber with each beat (regurgitation). Both stenosis and regurgitation result in ineffective pumping. The mitral and aortic valves are most likely to develop disorders.

Some valvular diseases are genetic, while other cases are caused by age-related damage, high blood pressure, or infections. Heart valve problems can lead to cardiomyopathy, as the heart muscle becomes larger and thicker to make up for the ineffective pumping of blood. Valvular disorders can also promote infection and blood clots, which may cause a heart attack or stroke.

Arrhythmia

Arrhythmia is a change in the heart’s normal rhythm, which can lead to ineffective heart pumping. This condition can also lead to a stroke or cardiac arrest (a sudden loss of heart function). Arrhythmia can be caused by damage to the heart’s SA node, for instance, during a heart attack. Arrhythmia may also be due to interruptions in how electrical impulses are communicated through the heart.

Types of arrhythmia include:

• Atrial fibrillation — This is the most common type of arrhythmia, with rapid, irregular contractions in the right and left atria.
• Ventricular fibrillation — The ventricles quiver instead of fully contracting and pumping effectively.
• Atrial flutter — The atria pump blood regularly, but they beat more rapidly than usual and are out of sync with the ventricles.
• Ventricular tachycardia — Rapid heartbeat in the ventricles does not allow them to fill with blood.
• Paroxysmal supraventricular tachycardia — Racing heartbeat originating in the atria starts and stops abruptly.
• Bradyarrhythmia — The heartbeat is slower than normal.

Cardiomyopathy

Cardiomyopathy is a heart muscle disease that can be caused by high blood pressure, heart attack, alcoholism, drug abuse, valvular heart disease, or arrhythmia. This disease usually causes the heart muscle to become thick, swollen, or stiff, making it harder to pump blood.

Types of cardiomyopathy include:

• Dilated cardiomyopathy — The most common type of cardiomyopathy usually begins with an enlarged left ventricle and eventually leads to an enlarged right ventricle and atria.
• Hypertrophic cardiomyopathy — Generally caused by abnormal genes in the heart, this condition causes the left ventricle to become thicker than usual.
• Restrictive cardiomyopathy — This occurs when the heart muscle becomes rigid due to scar tissue, which can be caused by a variety of health conditions.
• Arrhythmogenic cardiomyopathy — This rare form of cardiomyopathy occurs when normal heart tissue in the right ventricle dies and is replaced with scar tissue, causing arrhythmias.

Heart Inflammation

Inflammatory heart conditions are a less common type of heart disease. Heart inflammation can be caused by a viral, bacterial, or fungal infection. Autoimmune conditions may also cause inflammation in the heart. While inflammatory heart conditions may not be chronic, they can cause damage to heart tissues that leads to chronic heart problems.

Endocarditis is the inflammation of the inner lining of the heart and valves. Myocarditis is inflammation of the heart muscle itself, and pericarditis is inflammation of the sac that surrounds the heart.

Congenital Heart Defects

In the U.S., approximately 1 percent of people are born with congenital heart defects. About 25 percent of those born with congenital heart defects require surgery or medical procedures within their first year of life, with subsequent surgeries and medications possibly required. Some congenital heart defects are mild and do not produce symptoms until later in childhood or adolescence. As treatments improve, the life expectancy of people born with congenital heart defects continues to increase. It’s estimated that more than 2 million Americans have congenital heart defects.

Congenital heart defects can lead to the development of other types of heart disease.

Complications of Heart Disease

Heart disease can sometimes lead to complications — additional health problems that develop during an initial disease or during or after its treatments. These include heart attack, stroke, heart failure, and pulmonary hypertension.

Heart attack, also called myocardial infarction, is a life-threatening complication of heart disease. Heart attacks occur when an artery in the heart becomes blocked, limiting the oxygen supply to the heart tissues. Heart attacks cause permanent damage to the part of the heart where they occur by killing heart tissue. Damage caused by heart attacks can lead to arrhythmia and other problems.

According to the American Stroke Association, stroke is the fifth most common cause of death in the U.S. Strokes occur when arteries in the brain become narrowed or blocked or when there is bleeding in the brain. They may be caused by uncontrolled high blood pressure, atherosclerosis, or high levels of blood thinner medications.

Congestive heart failure occurs when the heart can no longer pump enough blood effectively. This causes a backup of blood flow and a buildup of fluid in the lungs, which can lead to breathing trouble. Many types of heart disease can progress to heart failure.

Pulmonary hypertension is high blood pressure in the lungs. Some forms of pulmonary hypertension are progressive and potentially fatal. Pulmonary hypertension can be caused by heart valve problems, coronary artery disease, heart failure, and many other health conditions. Since the lungs and heart are interdependent, pulmonary hypertension can cause arrhythmia and issues in the right side of the heart.

Talk With Others Who Understand

MyHeartDiseaseTeam is the social network for people with heart disease and their loved ones. More than 52,000 members come together to ask questions, give advice, and share their stories with others who understand life with heart disease.

Have you been diagnosed with heart disease? Share your experience in the comments below, or start a conversation by posting on MyHeartDiseaseTeam.