A disorder characterized by an electrocardiographic finding of a supraventricular arrhythmia characterized by the replacement of consistent P waves by rapid oscillations or fibrillatory waves that vary in size, shape and timing and are accompanied by an irregular ventricular response. (CDISC)

A disorder in which the two upper chambers of the heart beat fast and erratically. Because blood isn't pumped out of these chambers fully, it may pool and form clots that could lead to a stroke.

Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.

Atrial fibrillation, also known as AFib or AF, is one of the most common types of arrhythmias. Arrhythmias are problems with the rate or rhythm of your heartbeat. They can cause your heart to beat too slowly, too fast, or in an irregular way. If you have AFib, your heart beats irregularly and sometimes much faster than normal. Also, your heart's upper and lower chambers do not work together as they should. When this happens, the lower chambers do not fill completely or pump enough blood to your lungs and body. This can cause symptoms such as dizziness, fatigue, and a pounding heartbeat. AFib may happen in brief episodes, or it may be a permanent condition. It's very important to treat it, since AFib can put you at risk for stroke and other heart conditions. AFib is most often caused by changes to the heart's tissue or the electrical signaling that helps the heartbeat. These changes can happen due to different conditions and factors, such as high blood pressure, coronary artery disease, congenital heart defects, infections, and aging. Sometimes the cause is unknown. Anyone can develop AFib, but there are certain things that raise your risk for it: Aging. The risk of atrial fibrillation increases as you get older, especially when you are over age 65.; Family history and genetics. AFib can run in families. So can heart disease, which raises your risk of AFib.; Some lifestyle choices. Your risk is higher if you drink a lot of alcohol, use certain illegal drugs such as cocaine and methamphetamines, or smoke.; Having certain health conditions, such as: High blood pressure; Diabetes; Heart failure; Heart valve diseases; Obesity; Hyperthyroidism; Chronic kidney disease; COPD and other lung diseases; Sleep apnea.; Race. AFib is more common in people with European ancestry.; Recent surgery. You may be at risk of atrial fibrillation in the early days and weeks after surgery on your heart, lungs, or esophagus. Some people who have AFib don't have any symptoms and don't know they have it. If you do have symptoms, you may only notice them once in a while. Or you may have symptoms that are more frequent. And in some cases, the symptoms might be severe. If you have heart disease, you are more likely to notice your symptoms. And those symptoms could get worse if your heart disease gets worse. The symptoms of AFib can include: Extreme fatigue, which is the most common symptom; Heart palpitations (the feeling that your heart is skipping a beat, fluttering, pounding, or beating too hard or too fast); Trouble breathing, especially when lying down or when exercising; Chest pain; Dizziness or fainting; Low blood pressure. If AFib is not treated, it can lead to serious health problems (complications) such as: Stroke; Heart failure; Blood clots; Sudden cardiac arrest (SCA); Cognitive impairment and dementia. To help prevent these problems, it's important...

An atrial arrhythmia characterized by disorganized atrial activity without discrete P waves on the surface EKG, but instead by an undulating baseline or more sharply circumscribed atrial deflections of varying amplitude an frequency ranging from 350 to 600 per minute.

An irregular heart rhythm, usually associated with a rapid rate, that is caused by abnormal electrical activity within the atria.

Disorder of cardiac rhythm characterized by rapid, irregular atrial impulses and ineffective atrial contractions.

Irregular heart rhythm, usually associated with a rapid rate, that is caused by abnormal electrical activity within the atrial.

A disorder characterized by a dysrhythmia without discernible P waves and an irregular ventricular response due to multiple reentry circuits. The rhythm disturbance originates above the ventricles.

Atrial fibrillation is a rapid, irregularly irregular atrial rhythm. Symptoms include palpitations and sometimes weakness, effort intolerance, dyspnea, and presyncope. Atrial thrombi may form, causing a significant risk of embolic stroke. Diagnosis is by electrocardiography. Treatment involves rate control with drugs, prevention of...

Atrial fibrillation (AF) has strong associations with other cardiovascular diseases, such as heart failure, coronary artery disease (CAD), valvular heart disease, diabetes mellitus, and hypertension. It is characterized by an irregular and often rapid heartbeat (see the image below).

Atrial fibrillation is an irregular and often rapid heart rate that can increase your risk of strokes, heart failure and other heart-related complications.

Atrial fibrillation, irregular rhythm of contraction of the muscles of the atrium, the upper chamber of the heart. In some cases the fibrillations are not noticed by the patient, but frequently the chaotic, rapid, and shallow beats are felt as significant palpitations of the heart, often...