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Supraventricular TachycardiaTopic Overview
Is this topic for you? Atrial fibrillation and ventricular tachycardia are types of fast heart rates that can be serious. If you have one of these heart problems, see the topic Atrial Fibrillation or Ventricular Tachycardia. What is supraventricular tachycardia?Supraventricular tachycardia (SVT) means that from time to time your heart beats very fast for a reason other than exercise, high fever, or stress. Types of SVT include:
During an episode of SVT, the heart’s electrical system doesn't work right, causing the heart to beat very fast. The heart beats at least 100 beats per minute and may reach 300 beats per minute. After treatment or on its own, the heart usually returns to a normal rate of 60 to 100 beats a minute. SVT may start and end quickly, and you may not have symptoms. SVT becomes a problem when it happens often, lasts a long time, or causes symptoms. SVT also is called paroxysmal supraventricular tachycardia (PSVT) or paroxysmal atrial tachycardia (PAT). What causes SVT?Most episodes of SVT are caused by
faulty electrical connections in the heart SVT also can be caused by very high levels of the heart medicine digoxin (such as Lanoxicaps or Lanoxin) or the lung medicine theophylline (such as Theochron or Uniphyl). Some types of SVT may run in families, such as Wolff-Parkinson-White syndrome. Or they may be caused by a lung problem such as COPD or pneumonia. What are the symptoms?Some people with SVT have no symptoms. Others may have:
Other symptoms include, near-fainting or fainting (syncope), shortness of breath, chest pain, throat tightness, and sweating. How is SVT diagnosed?Your doctor will diagnose SVT by asking you questions about your health and symptoms, doing a physical exam, and perhaps giving you tests. Your doctor:
If you do not have an episode of SVT while you're at the doctor's office, your doctor probably will ask you to wear a portable EKG. When you have an episode, the device will record it. Your doctor also may do tests to find the cause of the SVT. These may include blood tests, a chest X-ray, and an echocardiogram, which makes a picture of the heart. How is it treated?Some SVTs don't cause symptoms, and you may not need treatment. If you do have symptoms, your doctor probably will recommend treatment. To treat sudden episodes of SVT, your doctor may:
If these treatments don't work, you may have to go to your doctor's office or the emergency room. You may get a fast-acting medicine such as adenosine or verapamil. If the SVT is serious, you may have electrical cardioversion, which uses an electrical current to reset the heart rhythm. If you often have episodes of SVT, you may need to:
What can you do at home to prevent SVT?You can do a lot to prevent SVT by avoiding the things that trigger it.
To find your triggers, keep a diary of your heart rate and your symptoms. You might find, for example, that smoking or caffeine causes your SVT episodes. Health ToolsHealth Tools help you make wise health decisions or take action to improve your health.
Frequently Asked Questions
CauseTwo common types of supraventricular tachycardia—atrioventricular reciprocating tachycardia (AVRT) and atrioventricular nodal reentrant tachycardia (AVNRT)—are caused by an abnormal electrical pathway in the heart and often occur in people who do not have any other type of heart disease. What causes this abnormal pathway is not clear. Some experts believe that AVRT—specifically Wolff-Parkinson-White syndrome—may in some cases be inherited. Other types of supraventricular tachycardia may be caused by:
SymptomsSymptoms of supraventricular tachycardia include:
What Increases Your RiskSome lifestyle factors can raise your risk of having an episode of supraventricular tachycardia, such as overuse of caffeine, nicotine, or alcohol or use of illegal drugs, such as stimulants like cocaine or methamphetamine. Decongestants that contain stimulants should also be avoided, including oxymetazoline (such as Afrin and other brands) and pseudoephedrine (such as Sudafed and other brands). Doctors also warn against using nonprescription diet pills or "pep" pills, because many contain caffeine, ephedra, ephedrine, the herb ma huang, or other stimulants. Conditions that affect the lungs, such as chronic obstructive pulmonary disease (COPD), pneumonia, heart failure, and pulmonary embolism, can raise your risk for multifocal atrial tachycardia (MAT), a type of supraventricular tachycardia. Many experts believe that Wolff-Parkinson-White syndrome may in some cases be inherited. If you have a first degree relative, which is a parent, brother, or sister, with this disorder and he or she has symptoms, talk with your doctor about your risk of developing this abnormal heart rhythm. When to Call a DoctorCall 911 or seek emergency services immediately if you have a fast heart rate and you:
Call your doctor if you are having fluttering in your chest (palpitations) that persists and does not go away quickly or if you have frequent palpitations. Watchful WaitingIf you have a fast heart rate and you have symptoms that may be caused by the fast heart rate, watchful waiting is not appropriate. See your doctor. Who to SeeHealth professionals who can evaluate symptoms of a fast or irregular heartbeat include:
Most people with supraventricular tachycardia need to see a cardiologist or electrophysiologist for follow-up care. Exams and TestsAn exact diagnosis is important because the treatment you receive depends on the type of tachycardia you have. Supraventricular tachycardia can sometimes be diagnosed simply on the basis of a medical history and physical examination and a few simple tests. The physical exam may include a carotid sinus massage. Tests that may be done to monitor your heart and diagnose the type of fast heart rate that you have include:
After finding tachycardia, your doctor may need to search for its cause. The specific tests needed depend on the particular tachycardia. These tests may include:
Treatment OverviewSupraventricular tachycardia is usually treated if:
Treatment for sudden-onset (acute) episodesWhen episodes of supraventricular tachycardia (SVT) start suddenly and cause symptoms, you can try vagal maneuvers—such as gagging, holding your breath and bearing down (Valsalva maneuver), immersing your face in ice-cold water (diving reflex), coughing, or putting pressure on your eyelids. These simple maneuvers stimulate the vagus nerve, which can slow conduction of electrical impulses that control your heart rate. Your doctor will teach you how to perform vagal maneuvers safely. Your doctor may also prescribe a short-acting medicine that you can take by mouth if vagal maneuvers don't work. This allows some people to manage their SVT without having to visit the emergency room repeatedly. If your heart rate cannot be slowed using vagal maneuvers, you may have to go to your doctor's office or the emergency room, where a fast-acting medicine such as adenosine or verapamil can be given. If the arrhythmia does not stop and symptoms are severe, electrical cardioversion, which uses an electrical current to reset the heart rhythm, may be needed. Ongoing treatment of recurring supraventricular tachycardiaIf you have recurring episodes of supraventricular tachycardia, you may need to take medicines, either on an as-needed basis or daily. Medicine treatment typically includes beta-blockers, calcium channel blockers, other antiarrhythmic medicines, or digoxin. In people with frequent episodes, treatment with medicines can decrease recurrences. But these medicines may have side effects. Many people with supraventricular tachycardia have a procedure called catheter ablation, which blocks abnormal electric impulses and can eliminate supraventricular tachycardia and the need to take medicines. But this procedure has risks, including infection, bleeding, and injury to the heart. If your heart is injured during catheter ablation, you will need a pacemaker. You must balance your feelings about taking medicine for the rest of your life with having an invasive procedure. Also, catheter ablation is not available everywhere and is best performed in a medical center that has staff experienced with this complicated procedure. Treatment for atrioventricular nodal reentrant tachycardia (AVNRT)In the case of atrioventricular nodal reentrant tachycardia (AVNRT), medicines can be taken—either daily or only when the fast heartbeat arises—or catheter ablation may be done. If you have infrequent episodes of AVNRT that last hours but do not cause severe symptoms, your doctor may recommend that you take medicines only when you have an episode. These medicines include antiarrhythmic medicines, calcium channel blockers, and beta-blockers. Your doctors may recommend daily doses of calcium channel blockers, beta-blockers, and/or digoxin if you have frequent episodes of AVNRT. If these medicines are not effective in stopping supraventricular tachycardia from recurring, your doctor may recommend that you take an antiarrhythmic medicine. If you take daily medicine for AVNRT or you have significant symptoms, you may want to consider having catheter ablation. Treatment for atrioventricular reciprocating tachycardia (AVRT)In the case of atrioventricular reciprocating tachycardia (AVRT), you can take medicines for recurrent episodes either on an as-needed or daily basis, depending on how frequently they occur. These medicines—which include beta-blockers, calcium channel blockers, and digoxin—are often effective in stopping or preventing episodes of AVRT. But in some people with a type of AVRT called Wolff-Parkinson-White (WPW) syndrome, digoxin and verapamil may result in extremely fast heart rates that can lead to lightheadedness, fainting (syncope), and even death. These drugs are only dangerous when given in an emergency when someone with Wolff-Parkinson-White syndrome is having atrial fibrillation. Treatment of WPW frequently requires antiarrhythmic medicines, such as propafenone (Rythmol) or flecainide (Tambocor), that slow electrical conduction over the extra connection. Catheter ablation is often recommended for people with WPW, especially those who have severe symptoms or also have atrial fibrillation or flutter. This procedure can successfully eliminate WPW most of the time. There is a small risk of the arrhythmia recurring even after successful ablation of WPW. But a second session of catheter ablation is usually successful. Ongoing ConcernsSymptoms of atrioventricular reciprocating tachycardia (AVRT), including Wolff-Parkinson-White (WPW) syndrome, usually start during the teen or young adult years. Episodes of WPW can trigger a life-threatening heart rhythm called ventricular fibrillation, although this is extremely rare. Your doctor may recommend that you wear a medical bracelet to alert medical professionals of your condition if you are at risk for ventricular fibrillation. AV nodal reentrant tachycardia (AVNRT) usually first causes symptoms from the teen years to middle age. After episodes of supraventricular tachycardia begin, they generally recur. These arrhythmias frequently stop spontaneously or with simple maneuvers, but you may have to take medicines daily if the arrhythmias keep happening. Medicine treatment typically includes beta-blockers, calcium channel blockers, or digoxin. In people with frequent episodes, treatment with an antiarrhythmic medicine can decrease recurrences, and catheter ablation can eliminate the arrhythmia altogether. When supraventricular tachycardia occurs in someone with significant coronary artery disease, the heart may not receive enough blood to keep up with the demands of the increased heart rate. If this occurs, the heart may not get enough oxygen, potentially causing chest pain (angina) or a heart attack. If tachycardia is left untreated, repeated and long episodes of tachycardia can lead to heart failure. But mild supraventricular tachycardia, with rare and short episodes, does not typically lead to heart failure.
PreventionYou can reduce your risk of having episodes of supraventricular tachycardia by avoiding certain stimulants or stressors, such as caffeine, nicotine, some medicines (for example, decongestants), illegal drugs (stimulants, like methamphetamines and cocaine), excess alcohol, lack of sleep, and overeating. If fast heart rates continue, long-term medicines such as beta-blockers may be used to help prevent a recurrence of the fast heart rate. Living With TachycardiaHome care includes monitoring your supraventricular tachycardia and trying to slow your heart when a fast heart rate occurs. To monitor your condition, you may find it helpful to keep a diary of your heart rate and your symptoms. Check your pulse By keeping a diary of your heart rate and symptoms, you may be able to identify stressors—such as lack of sleep, drinking alcohol, or overeating—that trigger episodes. Also, it's usually important to avoid overuse of caffeine, nicotine, or alcohol and the use of illegal drugs, such as stimulants like cocaine, ecstasy, or methamphetamine. For people who are especially sensitive, even decaffeinated teas or coffee can cause supraventricular tachycardia episodes. Decongestants that contain stimulants should also be avoided, including oxymetazoline (such as Afrin and other brands) and pseudoephedrine (such as Sudafed and other brands). Doctors also warn against using diet pills or "pep" pills (because many contain caffeine), ephedrine, ephedra, the herb ma huang, or other stimulants. Your doctor may suggest that you try vagal maneuvers—such as gagging, holding your breath and bearing down, or immersing your face in cold water—to slow your heart rate. Your doctor will help you learn these procedures so you can try them at home when your fast heart rate occurs.
MedicationsIf you have symptoms, medicines may be used to treat supraventricular tachycardia. Medication ChoicesFor severe symptoms, such as chest pain, shortness of breath, or feeling faint, you may be given fast-acting antiarrhythmic medicines by health professionals in the hospital emergency department, where your heart can be monitored. Fast-acting antiarrhythmic medicines commonly used to slow the heart rate during an episode include:
Long-term use of an antiarrhythmic medicine may also be needed to reduce the chance of having more episodes of supraventricular tachycardia or to reduce the heart rate during these episodes. Common medicines used for this purpose include: What to Think AboutAll medicines have side effects. See a table of medicines that may interact with other medicines and with pacemakers and implantable cardioverter defibrillators (ICDs).
SurgeryOpen-heart surgery for supraventricular tachycardia is performed rarely and is usually done only if surgery to remove abnormal electrical pathways (catheter ablation) or other treatments cannot be used. If you have heart surgery for another heart condition, catheter ablation may be done at the same time. Other TreatmentAn electric shock to the heart (electrical cardioversion) may be necessary if you are having severe symptoms of supraventricular tachycardia and your heart rate does not return to normal using vagal maneuvers or fast-acting medicines. If you continue to have episodes that cause serious symptoms, a procedure called catheter ablation may be done during an electrophysiology (EP) study. During an EP study, the extra electrical pathway or cells in the heart that are causing the fast heart rate can often be identified and destroyed using catheter ablation. If you have tried other treatment, such as medicine and catheter ablation, but still have tachycardia, a pacemaker might be an option. Other Treatment ChoicesWhat to think aboutElectrical cardioversion is only used in an emergency. If you are awake, medicines will be used to control pain and make you sleepy during the procedure. Catheter ablation is effective for people with severely symptomatic supraventricular tachycardia due to AV nodal reentrant tachycardia or a concealed bypass tract. It can also reduce medical costs when compared with commonly used drug therapies. Catheter ablation has risks, but they are rare. You must balance your feelings about taking medicine for the rest of your life with having an invasive procedure. A pacemaker might be an option for some people. Your doctor may suggest a pacemaker if you have symptoms and if medicine or catheter ablation have not worked for you. Other Places To Get HelpOrganizations
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