Heart rhythm problems, called 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 are often harmless – in fact, most people have occasional, irregular heartbeats. However, some heart arrhythmias may trigger bothersome or even life-threatening symptoms.
When your heart beats, the electrical impulses that cause it to contract follow a precise pathway through your heart. Any interruption in these impulses can cause a heart arrhythmia, including the following:
- Coronary artery disease
- Scarring of heart tissue (such as from a heart attack)
- Changes to heart structure (such as from cardiomyopathy, a disease that enlarges and weakens your heart muscle)
- High blood pressure
- High stress
- Alcohol or drug abuse
- Drinking too much caffeine
- Certain medications, dietary supplements or herbal treatments
- Electrical shock
Heart arrhythmias may not trigger any symptoms. In fact, your doctor might find you have a heart arrhythmia before you do, during a routine examination. But some people do have noticeable arrhythmia symptoms, which may include:
- Light “fluttering” in your chest
- Racing heartbeat (tachycardia)
- Slow heartbeat (bradycardia)
- Chest pain or discomfort
- Shortness of breath or wheezing
- Lightheadedness, dizziness, or fainting
Noticeable symptoms don't always indicate a serious problem. Some people who feel heart arrhythmias don't have a serious problem, while others who have life-threatening arrhythmias feel no symptoms at all.
Heart arrhythmia treatment can often control or eliminate irregular heartbeats. You may be able to reduce your arrhythmia risk by adopting a heart-healthy lifestyle. Rhythm disorders can be treated with medication, pacemakers, defibrillators or by using catheters to ablate or destroy the small area of the heart's tissue that is causing the rhythm problem.
Many types of fast heartbeats (called tachycardias) respond well to anti-arrhythmic medications. Though they don't cure the problem, they can reduce episodes of tachycardia or slow down the heart when an episode occurs. Some medications can slow down your heart so much that you may need a pacemaker. It's very important to take any anti-arrhythmic medication exactly as directed by your doctor to avoid complications.
If slow heartbeats (bradycardias) don't have a cause that can be corrected — such as low thyroid hormone levels or a drug side effect — doctors often treat them with a pacemaker. A pacemaker is a small, battery-powered 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, proper rate.
Cardioversion is a medical procedure performed to restore a normal heart rhythm for people who have certain types of abnormal or irregular heartbeats (arrhythmias). Cardioversion is most often performed by sending tiny electric shocks to your heart through electrodes placed on your chest.
Cardioversion is usually a scheduled procedure that's performed in a hospital, and many people are able go home the same day. For most, cardioversion quickly restores a normal heart rhythm.
Complications of electric cardioversion are rare, and doctors can take steps to reduce your risk. Major risks of cardioversion include:
- Skin burns. Some people get minor burns on their skin where electrodes were placed.
- Dislodged blood clots. People who have heart arrhythmias sometimes have blood clots in their hearts. Cardioversion can cause these clots to migrate to other parts of your body, which can cause life-threatening complications, such as a stroke (clot in the brain) or a pulmonary embolism (clot in the lungs). Your doctor will check for blood clots in your heart the procedure and prescribe blood-thinning medications if clots are found.
- Abnormal heart rhythm. In rare cases, some people who undergo cardioversion end up with other heart rhythm problems during or after their procedure. If this occurs, it usually shows up only minutes after your procedure, so your doctor can give you medications or additional electrical impulses to correct the problem.
Electrophysiology (EP) Test
Your doctor may recommend an EP test to pinpoint where in your heart your arrhythmia occurs and to check the severity of your condition. A catheter is threaded through a vein in your groin to your heart, similar to cardiac catheterization. Electrodes are passed through the catheter to different points in your heart to study the speed and location of the flow of electricity within the heart, mapping out any irregular heartbeats. The electrodes detect the electrical signals running through your heart to see if it has a tendency to shift into potentially dangerous slow or fast rhythms.
This treatment is for those who’ve tried medications to treat heart arrhythmia without success, have suffered serious side effects from the drugs, have certain types of arrhythmias that respond well to ablation, or have a high risk of complications from their arrhythmia, such as sudden cardiac arrest.
Ablation works by scarring or destroying tissue that blocks the electrical signal traveling through your heart to make it beat. Clearing the signal pathway of the abnormal tissue lets your heartbeat return to normal. The procedure is sometimes done through open heart surgery, but typically uses cardiac catheterization, making the procedure less invasive and shortening recovery time.
Cardiac ablation can normalize heart rhythms and reduce the risk of stroke. Cardiac catheterization is a minimally invasive procedure, providing a less painful and risky alternative to surgery. After ablation, many people no longer need anti-arrhythmic medications.
Your risk of complications may increase if you have diabetes or kidney disease, or if you are 75 or older. Possible complications include:
- Bleeding at the site where your catheter was inserted
- Narrowing of the veins that carry blood between your lungs and heart (pulmonary vein stenosis)
- Damage to your blood vessels where the catheter may have scraped as it traveled to your heart
- Damage to your heart's electrical system which could worsen your arrhythmia and require a pacemaker to correct
- Blood clots which could lead to heart attack or stroke
- Puncture of the heart