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, slow 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.
Arrhythmias may not cause any signs or symptoms. In fact, your doctor might find you have an arrhythmia before you do, during a routine examination. Noticeable signs and symptoms don’t necessarily mean you have a serious problem, however.
Noticeable arrhythmia symptoms may include:
- A fluttering in your chest
- A racing heartbeat (tachycardia)
- A slow heartbeat (bradycardia)
- Chest pain
- Shortness of breath
- Lightheadedness or dizziness
- Fainting (syncope) or near fainting
Many things can lead to, or cause, an arrhythmia, including:
- A heart attack that’s occurring right now
- Scarring of heart tissue from a prior heart attack
- Changes to your heart’s structure, such as from cardiomyopathy
- Blocked arteries in your heart (coronary artery disease)
- High blood pressure
- Overactive thyroid gland (hyperthyroidism)
- Underactive thyroid gland (hypothyroidism)
- Drinking too much alcohol or caffeine
- Drug abuse
- Certain medications and supplements, including over-the-counter cold and allergy drugs and nutritional supplements
- Sleep apnea
Types of arrhythmias:
Doctors classify arrhythmias not only by where they originate (atria or ventricles) but also by the speed of heart rate they cause:
- Tachycardia. This refers to a fast heartbeat — a resting heart rate greater than 100 beats a minute.
- Bradycardia. This refers to a slow heartbeat — a resting heart rate less than 60 beats a minute.
Not all tachycardias or bradycardias mean you have heart disease. For example, during exercise it’s normal to develop a fast heartbeat as the heart speeds up to provide your tissues with more oxygen-rich blood. During sleep or times of deep relaxation, it’s not unusual for the heartbeat to be slower.
Certain factors may increase your risk of developing an arrhythmia. These include:
- Coronary artery disease, other heart problems and previous heart surgery.Narrowed heart arteries, a heart attack, abnormal heart valves, prior heart surgery, heart failure, cardiomyopathy and other heart damage are risk factors for almost any kind of arrhythmia.
- High blood pressure. This increases your risk of developing coronary artery disease. It may also cause the walls of your left ventricle to become stiff and thick, which can change how electrical impulses travel through your heart.
- Congenital heart disease. Being born with a heart abnormality may affect your heart’s rhythm.
- Thyroid problems. Having an overactive or underactive thyroid gland can raise your risk of arrhythmias.
- Drugs and supplements. Certain over-the-counter cough and cold medicines and certain prescription drugs may contribute to arrhythmia development.
- Diabetes. Your risk of developing coronary artery disease and high blood pressure greatly increases with uncontrolled diabetes.
- Obstructive sleep apnea. This disorder, in which your breathing is interrupted during sleep, can increase your risk of bradycardia, atrial fibrillation and other arrhythmias.
- Electrolyte imbalance. Substances in your blood called electrolytes — such as potassium, sodium, calcium and magnesium — help trigger and conduct the electrical impulses in your heart. Electrolyte levels that are too high or too low can affect your heart’s electrical impulses and contribute to arrhythmia development.
- Drinking too much alcohol. Drinking too much alcohol can affect the electrical impulses in your heart and can increase the chance of developing atrial fibrillation.
- Caffeine or nicotine use. Caffeine, nicotine and other stimulants can cause your heart to beat faster and may contribute to the development of more-serious arrhythmias. Illegal drugs, such as amphetamines and cocaine, may profoundly affect the heart and lead to many types of arrhythmias or to sudden death due to ventricular fibrillation.
Certain arrhythmias may increase your risk of developing conditions such as:
- Stroke. When your heart quivers, it’s unable to pump blood effectively, which can cause blood to pool. This can cause blood clots to form. If a clot breaks loose, it can travel from your heart to your brain. There it might block blood flow, causing a stroke.Certain medications, such as blood thinners, can greatly lower your risk of stroke or damage to other organs caused by blood clots. Your doctor will determine if a blood-thinning medication is appropriate for you, depending on your type of arrhythmia and your risk of blood clots.
- Heart failure. Heart failure can result if your heart is pumping ineffectively for a prolonged period due to a bradycardia or tachycardia, such as atrial fibrillation. Sometimes controlling the rate of an arrhythmia that’s causing heart failure can improve your heart’s function.
To prevent heart arrhythmia, it’s important to live a heart-healthy lifestyle to reduce your risk of heart disease. A heart-healthy lifestyle may include:
- Eating a heart-healthy diet
- Increasing your physical activity
- Avoiding smoking
- Keeping a healthy weight
- Limiting or avoiding caffeine and alcohol
- Reducing stress, as intense stress and anger can cause heart rhythm problems
- Using over-the-counter medications with caution, as some cold and cough medications contain stimulants that may trigger a rapid heartbeat.
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.
- 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.
- Implantable loop recorder. This device detects abnormal heart rhythms and is implanted under the skin in the chest area.
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.
- 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, a 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.
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 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 by 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.
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.
Treatment for heart arrhythmias also may involve use of an implantable device:
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.