Atrial Fibrillation

  • Basics

    Atrial fibrillation occurs when the heart's two upper chambers quiver rather than beat effectively Figure 01.

    Click to enlarge: The heart

    Figure 01. The heart

    To beat effectively, the heart relies on an organized sequence of electrical impulses. Any deviation from this normal sequence is known as an “arrhythmia.” in the case of atrial fibrillation, the arrhythmia is one in which the heart beats too fast (tachycardia).

    Atrial fibrillation can cause a feeling of a racing heart or extra heartbeats (palpitations). However, sometimes it occurs without symptoms, in which case it can be discovered during a routine physical examination. If your condition is very serious or you have other forms of heart disease, your doctor will probably refer you to a heart specialist (cardiologist) to take over your care. If left untreated, atrial fibrillation can lead to heart failure or stroke.

    Atrial fibrillation is serious, but can be treated. Most patients with atrial fibrillation can lead normal lives. The heart returns to a normal rhythm in roughly 50% of people whose atrial fibrillation comes on suddenly. Whether or not someone with atrial fibrillation will require treatment depends on the severity of their symptoms and their person’s overall health, age, and lifestyle.

  • Causes

    Experts aren’t certain what causes atrial fibrillation Table 01. In many cases, atrial fibrillation results from an enlarged upper heart chamber (atrium), which can be caused by heart failure, high blood pressure over time, or diseased heart valves. Atrial fibrillation is also a common complication of heart surgery; especially among older people. It can also be caused by such illnesses as lung disease or asthma, from alcohol abuse or street drug use (primarily “uppers”), or from certain over-the-counter herbal preparations (such as Ephedra or ginseng). Atrial fibrillation can also occur without any obvious cause.

    Table 1.  Possible Causes of Atrial Fibrillation

    Situation Examples
    Existing heart disease Heart valve disease
    Cardiomyopathy
    Cardiomyopathy
    Coronary artery disease
    High blood pressure
    Heart disease present at birth
    Endocarditis
    Rheumatic heart disease
    Pericarditis
    Myocardial infarction (heart attack) ?
    Scarring, build up of deposits on the atria Commonly occurs with aging
    Heart surgery Cardiac bypass surgery
    Valve surgery
    Repair of congenital heart disease
    Illness Thyroid disease
    Diabetes
    Lung disease
    Asthma
    Alcohol intoxication
    Cardiac surgery
    Severe infection
    Non-heart-related causes Sudden alcohol toxicity
    Street drug ?uppers? (cocaine, amphetamines)
    Herbs (Ephedra, ginseng)
    Sleep apnea

Atrial Fibrillation Related Drugs