Heart Arrhythmia

Overview

Troubles of the heart

Heart arrhythmia (or dysrhythmia) is an abnormal change in your heart rate and/or rhythm. Arrhythmias, which affect many people, may cause the heart to beat faster than normal (tachycardia), slower than normal (bradycardia), or irregularly (erratic). They range from mild, asymptomatic disturbances to life-threatening conditions that may require immediate medical intervention.

Detailed Description

The heart is made up of four chambers: two atria and two ventricles. In a healthy heart, each of these chambers contracts in a precise sequence to move the maximum amount of blood while using the least amount of energy. Normally the heartbeat starts in the right atrium when a special group of cells called the sinus node (the "pacemaker" of the heart) sends an electrical signal. As the electrical impulse moves through the heart, the heart contracts — normally 60 to 100 times a minute. Each contraction represents one heartbeat. The atria contract a fraction of a second before the ventricles. This lets them empty their blood into the ventricles before the ventricles contract. Arrhythmias occur when the electrical impulse that controls these muscle contractions is disrupted.

Arrhythmias can be dangerous to the extent that they reduce the heart's ability to function properly. Very occasional irregular heartbeats are harmless and require no treatment. Most arrhythmias don't cause symptoms or interfere with the pumping action of the heart, so they pose little risk, and are readily controlled by proper medication. If, however, you experience recurring or persistent arrhythmia, or it is accompanied by other symptoms, such as chest pain or dizziness, contact a doctor immediately.

How Common Is Heart Arrhythmia?

Arrhythmias affect all age groups and occur equally in both sexes. Stress-related arrhythmia is more likely to occur in adults.

Conventional Treatment

Goals of Treatment

Most arrhythmias can be controlled with proper treatment. Depending on the nature and severity of the condition, your doctor may prescribe antiarrhythmic medication, implantation of a pacemaker, or both. If the arrhythmia is due to an underlying heart condition, more aggressive surgical intervention may be required. Very occasional irregular heartbeats are harmless and require no treatment.

In cases in which arrhythmia is due to lifestyle-related causes such as stress, overwork, or smoking, changes in behavior may end the problem. Arrhythmia stemming from organic causes, such as heart disease or endocrine disorders, can be controlled but not cured.

Treatment Overview

While most arrhythmias respond to drug therapy, you may need to try several drugs to find the most effective one for you. Also, because drugs can control but not cure arrhythmia, it is important that you strictly follow the regimen your doctor prescribes — even if you become symptom-free.

Call your doctor immediately if any new, unexplained symptoms develop because any of the drugs used in treatment may produce side effects. You should also inform your doctor immediately if you continue to experience heart problems despite being on medication.

A few arrhythmias can be life-threatening unless CPR (cardiopulmonary resuscitation) is performed immediately. As a matter of course, at least one family member, friend, or designated caregiver should be certified in this technique.

Drug Therapy

Beta-blockers
Inderal
Tenormin
Lopressor
Calcium-channel blocking agents
Calan
Cardizem
Other drugs for treating arrhythmias
Mexitil
Cordarone

Surgery

Depending on the nature and severity of the arrhythmia, surgical options could include a temporary pacemaker, a permanent pacemaker, or cardiac surgery.

A temporary pacemaker consists of a long, thin electrode wire, one end of which is inserted into the heart through a vein while the other end is attached to an external, battery-powered, pacemaker pulse generator. It can be left in place for up to several days until normal heart rhythms are restored.

With a permanent pacemaker, the pulse generator is implanted under the skin. The pacemaker is implanted while the patient is under local anesthesia, although patients may need to remain in bed for up to 24 hours following surgery in order to ensure that the leads have attached well to the heart wall.

Patients with recurring, life-threatening dysrhythmias may require an automatic implantable cardioverter defibrillator (AICD) implant. This device senses when the heart rhythm becomes abnormal and administers an electrical shock to the heart to correct the problem. AICD implantation, which requires making an incision in the chest, is done under general anesthesia; patients should expect to remain hospitalized for about a week following surgery.

If the arrhythmia is caused by an underlying cardiac condition, other surgical procedures may be required. The two most commonly performed surgeries to unblock the blood vessels leading to the heart are angioplasty and coronary bypass surgery, but a relatively new treatment called transmyocardial revascularization also shows promise for certain patients. The location and severity of the disease in the coronary arteries determine which procedure is chosen.

• Angioplasty
• Coronary bypass surgery
• Transmyocardial revascularization

Activity & Diet Recommendations

Psychotherapy or counseling may be helpful in alleviating arrhythmia if you and your doctor determine that stress is a major factor.

Some heart medicines require that you add extra potassium to your diet. Potassium-rich fruits include oranges, orange and grapefruit juice, bananas, melons, nectarines, prunes, peaches, pears, and avocados. Vegetables high in potassium include collard greens, cucumbers, potatoes, sweet potatoes, cabbage, beans, peas, winter squash, and tomatoes.

Monitoring the Condition

Your doctor may have to prescribe different antiarrhythmic medications to find the most suitable one for you. Record all side effects and report them to your doctor. Discontinue use immediately if the side effects are severe.

Possible Complications

The most serious cardiac rhythm disturbance is called ventricular fibrillation. The lower chambers of the heart quiver and the heart cannot pump any blood. Ventricular fibrillation is a life-threatening medical emergency.

Blood clots can form during atrial fibrillation, a condition in which the two small upper chambers of the heart quiver instead of beating effectively. Since blood isn't pumped completely out of the atria when the heart beats, the blood pools and clots. If a piece of the blood clot in the atria becomes lodged in an artery in the brain, a stroke results.

These serious arrhythmias are usually treated by defibrillation — an electric shock applied to the heart to reestablish a normal rhythm.

Quality of Life

If lifestyle factors are determined to be wholly or partially responsible for the arrhythmia, consider making serious behavioral changes. These could include abstaining from or significantly decreasing your consumption of alcohol and caffeine-containing beverages, quitting smoking, and actively seeking ways to reduce the stress level in your life.

Considerations for Women

Pregnancy

If you are pregnant, consult your doctor before taking any antiarrhythmic medication.

Nursing mothers

If you are breastfeeding, consult your doctor before taking any antiarrhythmic medication.

Considerations for Older People

Side effects of medication may be more frequent and severe in older people. Make sure your doctor is aware of any other medicines you already take.