Arrhythmia

Heart rhythm problems (heart arrhythmias) occur when the electrical impulses that coordinate your heartbeats don't work properly, causing your heart to beat too fast, too slow or irregularly.

Heart arrhythmias (uh-RITH-me-uhs) may feel like a fluttering or racing heart and may be harmless. However, some heart arrhythmias may cause bothersome — sometimes even life-threatening — signs and symptoms.

Heart arrhythmia treatment can often control or eliminate fast or irregular heartbeats. In addition, because troublesome heart arrhythmias are often made worse — or are even caused — by a weak or damaged heart, you may be able to reduce your arrhythmia risk by adopting a heart-healthy lifestyle.

Tests and diagnosis

To diagnose a heart arrhythmia, your doctor will review your symptoms and your medical history and conduct a physical examination. Your doctor may ask about — or test for — conditions that may trigger your arrhythmia, such as heart disease or a problem with your thyroid gland. Your doctor may also perform heart-monitoring tests specific to arrhythmias. These may include:

  • Electrocardiogram (ECG). During an ECG, sensors (electrodes) that can detect the electrical activity of your heart are attached to your chest and sometimes to your limbs. An ECG measures the timing and duration of each electrical phase in your heartbeat.
  • Holter monitor. This portable ECG device can be worn for a day or more to record your heart's activity as you go about your routine.
  • Event monitor. For sporadic arrhythmias, you keep this portable ECG device available, attaching it to your body and pressing a button when you have symptoms. This lets your doctor check your heart rhythm at the time of your symptoms.
  • Echocardiogram. In this noninvasive test, a hand-held device (transducer) placed on your chest uses sound waves to produce images of your heart's size, structure and motion.

If your doctor doesn't find an arrhythmia during those tests, he or she may try to trigger your arrhythmia with other tests, which may include:

  • Stress test. Some arrhythmias are triggered or worsened by exercise. During a stress test, you'll be asked to exercise on a treadmill or stationary bicycle while your heart activity is monitored. If doctors are evaluating you to determine if coronary artery disease may be causing the arrhythmia, and you have difficulty exercising, then your doctor may use a drug to stimulate your heart in a way that's similar to exercise.
  • Tilt table test. Your doctor may recommend this test if you've had fainting spells. Your heart rate and blood pressure are monitored as you lie flat on a table. The table is then tilted as if you were standing up. Your doctor observes how your heart and the nervous system that controls it respond to the change in angle.
  • Electrophysiological testing and mapping. In this test, doctors thread thin, flexible tubes (catheters) tipped with electrodes through your blood vessels to a variety of spots within your heart. Once in place, the electrodes can map the spread of electrical impulses through your heart. In addition, your cardiologist can use the electrodes to stimulate your heart to beat at rates that may trigger — or halt — an arrhythmia. This allows your doctor to see the location of the arrhythmia and what may be causing it.

Treatments and drugs

If you have an arrhythmia, treatment may or may not be necessary. Usually it's required only if the arrhythmia is causing significant symptoms or if it's putting you at risk of a more serious arrhythmia or arrhythmia complication.

Treating slow heartbeats

If slow heartbeats (bradycardias) don't have a cause that can be corrected, doctors often treat them with a pacemaker because there aren't any medications that can reliably speed up your heart.

A pacemaker is a small device that's usually implanted near your collarbone. One or more electrode-tipped wires run from the pacemaker through your blood vessels to your inner heart. If your heart rate is too slow or if it stops, the pacemaker sends out electrical impulses that stimulate your heart to beat at a steady rate.

Treating fast heartbeats

For fast heartbeats (tachycardias), treatments may include one or more of the following:

  • Vagal maneuvers. You may be able to stop an arrhythmia that begins above the lower half of your heart (supraventricular tachycardia) by using particular maneuvers that include holding your breath and straining, dunking your face in ice water, or coughing. These maneuvers affect the nervous system that controls your heartbeat (vagus nerves), often causing your heart rate to slow. However, vagal maneuvers don't work for all types of arrhythmias.
  • Medications. For many types of tachycardia, you may be prescribed medication to control your heart rate or restore a normal heart rhythm. It's very important to take any anti-arrhythmic medication exactly as directed by your doctor in order to minimize complications.

If you have atrial fibrillation, your doctor may prescribe blood-thinning medications to help keep dangerous blood clots from forming.

  • Cardioversion. If you have a certain type of arrhythmia, such as atrial fibrillation, your doctor may use cardioversion, which can be conducted as a procedure or using medications.

In the procedure, a shock is delivered to your heart through paddles or patches on your chest. The current affects the electrical impulses in your heart and can restore a normal rhythm.

  • Catheter ablation. In this procedure, your doctor threads one or more catheters through your blood vessels to your heart. Electrodes at the catheter tips can use heat, extreme cold or radiofrequency energy to damage (ablate) a small spot of heart tissue and create an electrical block along the pathway that's causing your arrhythmia.

Implantable devices

Treatment for heart arrhythmias also may involve use of an implantable device:

  • Pacemaker. A pacemaker is an implantable device that helps control abnormal heart rhythms. A small device is placed under the skin near the collarbone in a minor surgical procedure. An insulated wire extends from the device to the heart, where it's permanently anchored.

If a pacemaker detects a heart rate that's abnormal, it emits electrical impulses that stimulate your heart to beat at a normal rate.

  • Implantable cardioverter defibrillator (ICD). Your doctor may recommend this device if you're at high risk of developing a dangerously fast or irregular heartbeat in the lower half of your heart (ventricular tachycardia or ventricular fibrillation). If you have had sudden cardiac arrest or have certain heart conditions that increase your risk of sudden cardiac arrest, your doctor may also recommend an ICD.

An ICD is a battery-powered unit that's implanted under the skin near the collarbone — similar to a pacemaker. One or more electrode-tipped wires from the ICD run through veins to the heart. The ICD continuously monitors your heart rhythm. If it detects an abnormal heart rhythm, it sends out low- or high-energy shocks to reset the heart to a normal rhythm. An ICD doesn't prevent an abnormal heart rhythm from occurring, but it treats it if it occurs.

Surgical treatments

In some cases, surgery may be the recommended treatment for heart arrhythmias:

  • Maze procedure. In the maze procedure, a surgeon makes a series of surgical incisions in the heart tissue in the upper half of your heart (atria) to create a pattern or maze of scar tissue. Because scar tissue doesn't conduct electricity, it interferes with stray electrical impulses that cause some types of arrhythmia.

The procedure is effective, but because it requires surgery, it's usually reserved for people who don't respond to other treatments or for those who are having heart surgery for other reasons. The surgeon may use radiofrequency energy or extreme cold (cryotherapy) to create the scars.

  • Coronary bypass surgery. If you have severe coronary artery disease in addition to arrhythmias, your doctor may perform coronary bypass surgery. This procedure may improve the blood flow to your heart.