Abnormal Heart Rhythms/Arrhythmias
What are abnormal heart rhythms, or arrhythmias?
Your heart muscle beats many times a minute with a speed and pattern known as your heart rhythm or rate. When signals from the heart’s electrical system are somehow disrupted, the heart rate or rhythm is affected. Your heart may beat too slowly (bradycardia), too quickly (tachycardia) or irregularly (fibrillation), causing a decrease in blood flow. These heart rhythm problems are called arrhythmias or dysrhythmias.
There are many types of arrhythmia, most of which are not life-threatening. The most common kinds include:
- Atrial and ventricular fibrillation - Millions of people live with atrial fibrillation, or atrial flutter, in which the upper heart chambers beat very fast and irregularly. This is not immediately life-threatening but, if left untreated, atrial fibrillation could ultimately lead to a stroke. Ventricular fibrillation is a form of cardiac arrest and, therefore, is considered life-threatening.
- SVT – Super ventricular Tachycardia. This rhythm starts in the atria and has a rate faster than 100 beats per minute. It can cause dizziness or passing out.
- WPW – Wolf-Parkinson-White Syndrome. This rhythm is caused by an extra electrical “wire” in the heart between the atria and ventricles. It can be diagnosed with an EKG and monitored by your physician.
Both SVT and WPW can be permanently cured with a cardiac ablation.
What causes arrhythmias?
Arrhythmias are caused by heart problems like heart attack; congenital defects; complications from chemicals in your body (drug toxicity, nicotine or caffeine); your body’s reaction to an infection; or a change in your body’s electrolytes (naturally-occurring calcium, sodium or potassium).
A normal heart rate is between 60 and 100 beats a minute. Acceptable heart rhythms or rates vary person to person. If you suspect you have arrhythmia, tell your physician.
Your physician may recommend undergoing an electrophysiology study to pinpoint the problem. The information that study provides will help determine what treatment you need. Mercy’s Electrophysiology Lab provides this procedure and others in diagnosing heart problems.
What are the symptoms of arrhythmia?
- Shortness of breath
- Chest pain (angina)
- Heart racing or skipping a beat
- Heart palpitations
- Weakness
- Fainting
You can determine if you have an irregular heartbeat by checking the pulse on your wrist for 15 seconds and multiply by four the number of beats you count. If your heart rate is under 60 beats a minute, over 100 beats, or is irregular, contact your physician.
How is arrhythmia diagnosed?
Through an electrocardiogram, which produces a graphic record of the heart’s electrical activity. Results from this test are interpreted by a physician, who can then determine whether you have a slow heart rate (bradycardia) that’s below 60, a normal rate or a faster than normal rate (tachycardia) that’s over 100, or irregular.
What treatment is available?
Abnormal heart rates are rarely life-threatening, and do not cause heart attacks. However, abnormal heart rhythms can.
Abnormal heart rates can occur in people of all ages and fitness levels. Abnormal heart rhythms need to be evaluated to be sure they are treated – if necessary - properly. Sometimes medication, a pacemaker or other procedures or devices may be needed to control rhythm disturbances.
Medication
- Beta-blockers (Metoprolol, Atenolol, Propranolol) - help relax your heart so its heartbeat slows and is less stressed.
- Calcium channel blockers (Diltiazem, Verapamil, Nifedipine) - these slow conduction of atrial fibrillation and atrial flutter waves to the ventricles, keeping the ventricular rate from becoming too fast. They also dilate coronary arteries to increase their blood flow.
- Anti-arrhythmics (Sotalol, Amiodarone, Mexilitine, Procainamide) - there are several types of these. They work on various parts of the heart to control abnormal rhythms.
- Digoxin - many people with atrial fibrillation take this to help strengthen the heart beat.
- Coumadin - a “blood thinner,” this interferes with blood clotting. Patients who are in atrial fibrillation take this to prevent strokes.
Procedures
- Ablation – burning abnormal tissue with catheters placed inside the heart to eliminate arrhythmias. This can be done in many different parts of the heart, depending on where the abnormal rhythm originates.
- Cardioversion – shocking the heart into a normal rhythm with patches placed on the chest.
Devices
- A permanent pacemaker: these help patients whose hearts beat too slowly, by helping the heart establish a more regular rhythm.
- Implantable cardioverter defibrillator (ICD) implant: this is a small device implanted to control dangerous ventricular rhythms. It gives a shock to restore a normal rhythm.
For more information on Mercy’s Electrophysiology Lab, where the latest treatment for correcting abnormal heart rates is offered, click here.
For more information on dysrhythmia and other heart conditions from the American Heart Association, click here www.americanheart.org or from the Heart Rhythm Society, click here www.HRSonline.org.
