When functioning properly, your heart rhythm is coordinated and well-timed, with your two upper chambers (atria) contracting first, followed by the two lower chambers (ventricles), both powered by the heart’s own electrical system.
When that electrical system doesn’t function the way it should, the result is an abnormal heart rhythm, known as arrhythmia.
Atrial fibrillation (also known as AF or AFib) is the most common form of arrhythmia. AF occurs when different electrical impulses mistakenly fire all at once, creating a very fast, chaotic rhythm in the atria. As a result, the atria cannot effectively move blood into the ventricle, causing blood to pool in the heart. Over time, this chaotic rhythm can weaken the heart and lead to heart failure and stroke.
Signs & Symptoms
As many as one-third of patients with arrhythmias may show no symptoms at all, with heartbeat irregularities discovered during a routine exam. However, some patients report the following symptoms:
- Irregular heartbeat
- Shortness of breath
- Heart palpitations (rapid, flutter or pounding)
- Chest discomfort/pain
- Extreme fatigue
Diagnosing an Arrhythmia - What to Expect
To diagnose a heart arrhythmia, your doctor will review your symptoms and medical history and conduct a physical. He or she might also order noninvasive heart-monitoring tests that are specific to diagnosing arrhythmias. These can include:
- Electrocardiogram (ECG/EKG) – This test uses a machine that is attached to the legs, arms and chest through 10 electrodes. The ECG/EKG records the heart’s electrical signals that create heart rhythms.
- Echocardiogram – This noninvasive imaging technique records a videotaped image of heart structures, showing the heart’s chambers and valves in motion.
- Holter Monitoring – A Holter monitor is a small phone-sized device attached to a patient’s chest by five adhesive electrode patches. The monitor records the heart rhythm for 24-48 hours.
- Event Recorder – This small, phone-sized recording device detects and records arrhythmias and can be worn for up to a month.
- Tilt Table Test – This test helps evaluate blood pressure-related causes for fainting (syncope). The patient rests on a special table that tilts him or her upright at a 70-80 degree angle for 30-45 minutes while their heart rhythm and blood pressure are recorded.
Treatments for Arrhythmia
Some arrhythmias are self-limiting and require very little treatment. However, left untreated, other arrhythmias can dramatically increase the risk of stroke, heart failure and sudden death. Treatment options may include the following:
- Rate control medications
- Rhythm control medications
- Anticoagulants – medications given to decrease blood clotting
- Implantable cardioverter defibrillator (ICD)
- Pacemaker – single-chamber, dual-chamber or biventricular
- Cardioversion – uses a medication or electric current to reset the heart rhythm
- Catheter ablation – a minimally invasive procedure that cauterizes the exact heart regions where irregular heart rhythms originate
- Surgical ablation – a procedure performed through incisions in the chest to remove or destroy the abnormal tissue that is causing the arrhythmia. This is often combined with other heart surgeries such as coronary bypass surgery or valve repair or replacement
- Convergent (hybrid) ablation – a procedure that is a treatment alternative for atrial fibrillation patients who have failed other ablations or who have an enlarged atria, which is often indicative of structural heart disease
Risk Factors for Atrial Fibrillation
Though associated with many conditions, there’s no single cause of atrial fibrillation. Factors that can increase the risk of developing an arrhythmia or AF include:
- Narrowed heart arteries
- A previous heart attack
- Abnormal heart valves
- Prior heart surgery, heart failure, cardiomyopathy and other heart damage
- High blood pressure
- Congenital heart disease
- Overactive or underactive thyroid gland
- Taking certain over-the-counter cough and cold medicines and certain prescription drugs
- Obstructive sleep apnea
- Electrolyte imbalance
- Drinking too much alcohol
- Caffeine or nicotine use
- Sex (men are more likely than women to develop AF)