Atrial Fibrillation: Symptoms, Causes, and Treatment

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in the world, affecting millions of people. In this condition, the atria (upper chambers of the heart) beat chaotically and in an uncoordinated manner instead of rhythmically and efficiently. Although it is not always an immediate emergency, atrial fibrillation significantly increases the risk of stroke and can deteriorate heart function if not properly treated.

What is atrial fibrillation

In a healthy heart, an electrical signal originates in the sinus node (the heart's natural pacemaker) and propagates in an orderly fashion through the atria and then to the ventricles, producing a coordinated and efficient heartbeat. In atrial fibrillation, multiple abnormal electrical impulses fire simultaneously in the atria, causing them to quiver or fibrillate rather than contracting effectively. This produces an irregular and frequently rapid heart rhythm.

Atrial fibrillation can be classified as:

• ●Paroxysmal: episodes that begin and end spontaneously, generally within less than 7 days
• ●Persistent: the arrhythmia lasts more than 7 days and requires intervention (medication or cardioversion) to restore normal rhythm
• ●Long-standing persistent: atrial fibrillation persists for more than 12 months
• ●Permanent: the decision has been made not to attempt restoration of normal rhythm, and treatment focuses on controlling the heart rate

Symptoms of atrial fibrillation

Symptoms vary enormously between patients. Some have very bothersome symptoms while others feel nothing and the arrhythmia is discovered incidentally:

• ●Palpitations: sensation of rapid, irregular, or strong heartbeats in the chest. This is the most common symptom
• ●Fatigue and weakness: loss of effective atrial contraction reduces cardiac output by up to 25%, causing tiredness
• ●Shortness of breath: especially with physical exertion, climbing stairs, or walking briskly
• ●Dizziness or feeling of unsteadiness: due to rhythm irregularity and blood pressure fluctuations
• ●Chest pain or discomfort: pressure or tightness that may be confused with other conditions
• ●Exercise intolerance: noticeable reduction in the ability to perform usual physical activity
• ●Anxiety: the perception of irregular heartbeats causes distress in many patients

Causes and risk factors

Atrial fibrillation can be associated with multiple conditions:

• ●Hypertension: the most common risk factor, present in the majority of AF patients
• ●Advanced age: prevalence increases significantly after age 65
• ●Valvular heart disease: especially mitral stenosis or regurgitation
• ●Heart failure: both a cause and a consequence of atrial fibrillation
• ●Coronary artery disease: ischemic heart disease predisposes to arrhythmias
• ●Thyroid disease: hyperthyroidism is a classic and treatable cause of AF
• ●Obstructive sleep apnea: an increasingly recognized risk factor
• ●Obesity: being overweight independently increases AF risk
• ●Excessive alcohol consumption: the so-called holiday heart syndrome
• ●Diabetes mellitus: increases risk through atrial remodeling
• ●Chronic lung disease: COPD and other pulmonary conditions
• ●Recent cardiac or thoracic surgery: a common transient cause

Diagnosing atrial fibrillation

The diagnosis is confirmed through cardiac electrical studies:

• ●Electrocardiogram (ECG): shows an irregularly irregular rhythm with absence of defined P waves and presence of fibrillatory f waves. This is the confirmatory study
• ●24-48 hour Holter monitoring: essential for detecting paroxysmal episodes not captured on an office ECG
• ●Event monitor: for sporadic episodes requiring prolonged monitoring
• ●Echocardiogram: evaluates atrial size, ventricular function, and the presence of intracardiac thrombi (clots)
• ●Blood tests: thyroid function, electrolytes, kidney function, coagulation studies
• ●Transesophageal echocardiogram: in selected cases, to evaluate the left atrial appendage where most thrombi form

Stroke risk

The most feared complication of atrial fibrillation is embolic stroke. When the atria fibrillate without contracting effectively, blood can pool and form clots, especially in the left atrial appendage. If a clot breaks loose, it can travel to the brain and cause a potentially devastating stroke.

Stroke risk is assessed using the CHA2DS2-VASc score, which considers factors such as heart failure, hypertension, age, diabetes, prior stroke, vascular disease, and sex. Based on the score, the cardiologist determines whether the patient needs anticoagulation.

Treatment options

Rate control

Medications such as beta-blockers (metoprolol, bisoprolol), calcium channel blockers (diltiazem, verapamil), or digoxin are used to keep the heart rate within an acceptable range, even though the arrhythmia persists.

Rhythm control (restoring normal rhythm)

The goal is to restore and maintain normal sinus rhythm. Strategies include:

• ●Electrical cardioversion: a synchronized electrical shock is delivered under brief sedation to restore normal rhythm. It is a safe and effective procedure
• ●Anti-arrhythmic drugs: medications such as amiodarone, flecainide, or propafenone to maintain sinus rhythm after cardioversion
• ●Catheter ablation: a minimally invasive procedure in which the pulmonary veins (the main source of abnormal impulses) are isolated using radiofrequency energy or cryoablation. It offers success rates exceeding 70% in a first session

Anticoagulation (stroke prevention)

Direct oral anticoagulants (apixaban, rivaroxaban, dabigatran, edoxaban) or warfarin dramatically reduce the risk of stroke. The decision to anticoagulate depends on the CHA2DS2-VASc score and the individual bleeding risk.

Living with atrial fibrillation

• ●Take your medications exactly as prescribed by your cardiologist, especially anticoagulants
• ●Monitor your pulse regularly; learn to detect if your rhythm is irregular
• ●Moderate caffeine and alcohol intake, known triggers for episodes
• ●Maintain a healthy weight; weight loss in obese patients significantly reduces AF episodes
• ●Treat sleep apnea if you have it; CPAP use improves arrhythmia control
• ●Engage in moderate, regular exercise, consulting with your cardiologist about appropriate intensity
• ●Strictly control blood pressure, diabetes, and cholesterol

When to seek emergency care

• ●Palpitations accompanied by severe chest pain
• ●Severe breathing difficulty that does not improve with rest
• ●Sudden weakness on one side of the body, difficulty speaking, or vision loss (signs of stroke)
• ●Fainting or loss of consciousness
• ●Sustained heart rate above 150 beats per minute with severe symptoms

Atrial fibrillation is a treatable condition. With the correct diagnosis, appropriate anticoagulation, and the right control strategy, most patients can lead a normal and active life. At ElderCardio, Dr. Jimenez Iglesias offers comprehensive evaluation with electrocardiogram, Holter monitoring, and echocardiogram to diagnose and treat atrial fibrillation holistically. Schedule your appointment at (998) 116-3657 and take control of your heart rhythm.

Dr. Elders Jimenez Iglesias

Cardiologist · Nuclear Cardiology

Professional License: 13819257 · Specialty: 12543211