Atrial fibrillation
Atrial fibrillation (A-Fib or AF) is an abnormal heart rhythm characterized by disorganized electrical impulses in the atria, which can lead to ineffective heart contractions. Commonly associated with underlying heart conditions, it may arise from factors such as hypertension, heart surgery, or lifestyle choices, including alcohol consumption and drug use. Symptoms can vary widely; some individuals may experience palpitations, shortness of breath, or lightheadedness, while others may be asymptomatic. The condition can be acute or chronic, and its management typically involves a combination of restoring normal heart rhythm, controlling heart rate, and preventing complications like stroke through anticoagulants.
Treatment options include electrical cardioversion, antiarrhythmic medications, and lifestyle modifications. Advances in understanding atrial fibrillation's genetic and risk factor interdependencies are crucial, as the condition is expected to rise globally in the coming years. By addressing underlying health issues and refining treatment approaches, patients can achieve better outcomes and reduce the risks associated with this complex cardiac condition.
Atrial fibrillation
ANATOMY OR SYSTEM AFFECTED: Cardiovascular system, heart
DEFINITION: Abnormal heart rhythm or muscle contractions in the atria as a result of disorganized electrical impulses.
CAUSES:Hypertension, acute myocardial infarction, valvular heart disease, heart surgery, thyroid disorders, pulmonary clots, acute alcohol ingestion, cocaine use, pneumonia, congenital or other heart defects, surges in vagal tone, idiopathic
SYMPTOMS: Often asymptomatic; sometimes heart palpitations or fluttering, chest tightness, shortness of breath, lightheadedness
DURATION: Acute or chronic
TREATMENTS: Electrical cardioversion, antiarrhythmics, anticoagulants, ablation, Maze procedure
Causes and Symptoms
Atrial fibrillation, also called A-Fib or AF, may occur with or without heart abnormalities, but commonly there is an underlying heart condition. Patients with atrial fibrillation often have a stiffening of the arteries, aortic stenosis, or enlargement of the left ventricle. Also, hypertension (high blood pressure) is a predisposing factor of this conduction irregularity. Other risk factors include aging, obesity, sleep apnea, diabetes, and myocardial infarction (heart attack). An accurate model to describe the cause of atrial fibrillation is one recognizing the interdependence between genetics, the heart’s response to risk factors, and aging.
Atrial fibrillation is usually characterized by electrical conduction abnormalities seen on an electrocardiogram (ECG or EKG), which analyzes the heart’s rhythm. Three common conduction abnormalities are intermittent, persistent, and permanent.
The disease is characterized by a variety of symptoms, and some patients are without symptoms. A patient might describe feeling either a slow heartbeat (for example, heart “pauses”) or a fast heartbeat. Other symptoms that may occur during an atrial fibrillation episode are shortness of breath, lightheadedness or dizziness, fatigue, and chest discomfort.
Treatment and Therapy
There are generally three treatment categories for atrial fibrillation: acute, subacute, and chronic. The primary goal of therapy, when possible, is restoring the heart to a sinus rhythm. Additionally, treatments focus on preventing thromboembolic complications of atrial fibrillation and rate control.
If the patient is experiencing acute atrial fibrillation, then the causative factors should be addressed. Often, electrical cardioversion is still the treatment of choice. Heart rates often are controlled effectively with medications such as beta-blockers, calcium channel blockers, or digoxin. Rare complications including embolic stroke may result because of the lack of proper blood flow in the atria coincident with the abnormal contractions (fibrillation). Anticoagulants (blood thinners) such as aspirin or warfarin are used to prevent stroke. In some instances, ablation therapy, antiarrhythmic medications, or the Maze procedure (which creates new electrical pathways through the heart using scar issue) may be used.
Lifestyle changes such as trigger avoidance and regular exercise may help patients avoid recurrences of acute atrial fibrillation.
Perspective and Prospects
It is projected that atrial fibrillation will continue to increase in incidence worldwide over the next few decades. Therefore, improvements in both the classification and the characterization of the disease are imperative. Refining the understanding of genetics, such as chromosome 4 variants, offer prospects for intervention. Stroke prevention, comprehensive treatment including both rate and rhythm control, and management of underlying conditions may also help mitigate atrial fibrillation.
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