An abnormal heartbeat (arrhythmia) is any variation in the normal heartbeat. Abnormal heartbeats occur when the heart has an irregular heart rhythm, beats too fast (tachycardia), or beats too slow (bradycardia).
The electrical system of the heart creates signals that trigger the heart to pump. These electrical signals control the heart rate and rhythm. Normally, the heart beats in a regular rhythm and at a rate that is appropriate for the work the body is doing. An arrhythmia results from a problem in the electrical system of the heart. Things that can cause the heart to beat abnormally include heavy smoking, alcohol use, excess caffeine or other stimulants, stress, thyroid disease, and fever.
Many arrhythmias are minor, causing only occasional abnormal heartbeats and requiring no treatment. Others, such as atrial fibrillation, can be life-threatening because they increase the risk of blood clots and strokes. Arrhythmias are of special concern in people who also have heart disease or heart failure. Some arrhythmias can be treated with medication. Others may require an electrical shock (cardioversion), surgery, or a pacemaker.
How are arrhythmias treated?
Some arrhythmias may be present but cause few, if any, problems. In this case, the doctor may elect not to treat the arrhythmia. However, when the arrhythmia causes symptoms, there are several different options for treatment. The doctor will choose an arrhythmia treatment based on the type of arrhythmia, the severity of symptoms being experienced, and the presence of other conditions (diabetes, kidney failure, heart failure, etc.) which can affect the course of the treatment.
Some treatments for arrhythmias include:
- Lifestyle modification. Factors, such as stress, caffeine, or alcohol, can cause arrhythmias. The doctor may order the elimination of caffeine, alcohol, or any other substances believed to be causing the problem. If stress is suspected as a cause, the doctor may recommend stress-reduction measures, such as meditation, stress-management classes, an exercise program, or psychotherapy.
- Medication. There are various types of medications that may be used to treat arrhythmias. If the doctor chooses to use medication, the decision of which medication to use will be determined by the type of arrhythmia, other conditions which may be present, and other medications already being taken by the patient.
- Cardioversion. In this procedure, an electrical shock is delivered to the heart through the chest to stop certain very fast arrhythmias such as atrial fibrillation, supraventricular tachycardia, or atrial flutter. The patient is connected to an ECG monitor which is also connected to the defibrillator. The electrical shock is delivered at a precise point during the ECG cycle to convert the rhythm to a normal one.
- Ablation. This is an invasive procedure done in the electrophysiology laboratory, which means that a catheter (a very thin, flexible hollow tube) is inserted into the heart through a vessel in the groin or arm. The procedure is done in a manner similar to the electrophysiology studies (EPS) described above. Once the site of the arrhythmia has been determined by EPS, the catheter is moved to the site. By use of a technique, such as radiofrequency ablation (very high frequency radio waves are applied to the site, heating the tissue until the site is destroyed) or cryoablation (an ultra-cold substance is applied to the site, freezing the tissue and destroying the site), the site of the arrhythmia may be destroyed.
- Pacemaker. A permanent pacemaker is a small device that is implanted under the skin (most often in the shoulder area just under the collar bone), and sends electrical signals to start or regulate a slow heart beat. A permanent pacemaker may be used to make the heart beat if the heart's natural pacemaker (the SA node) is not functioning properly and has developed an abnormal heart rate or rhythm or if the electrical pathways are blocked. Pacemakers are typically used for slow arrhythmias such as sinus bradycardia, sick sinus syndrome, or heart block.
- Implantable cardioverter defibrillator. An implantable cardioverter defibrillator (ICD) is a small device, similar to a pacemaker, that is implanted under the skin, often in the shoulder area just under the collarbone. An ICD senses the rate of the heartbeat. When the heart rate exceeds a rate programmed into the device, it delivers a small, electrical shock to the heart in order to shock the heart back to a slower more normal heart rhythm. Newer ICDs are combined with a pacemaker to deliver an electrical signal to regulate a heart rate that is too slow. ICDs are used for life-threatening fast arrhythmias such as ventricular tachycardia or ventricular fibrillation.
- Surgery. Surgical treatment for arrhythmias is usually done only when all other appropriate options have failed. Surgical ablation is a major surgical procedure requiring general anesthesia. The chest is opened, exposing the heart. The site of the arrhythmia is located, the tissue is destroyed or removed in order to eliminate the source of the arrhythmia.