What is paroxysmal supraventricular tachycardia (PSVT)?

The heart is a two-stage electrical pump. A coordinated electrical signal is required for the heart muscle cells to contract in a coordinated way and generate a heartbeat. Normally, an electrical signal is generated in special pacemaker cells found in the sinoatrial (SA) node located in the right atrium or upper chamber of the heart. This impulse spreads to the whole atrial muscle causing it to contract and push blood into the ventricle or the lower chamber of the heart. The electrical signal continues to a junction box between the atrium and ventricle (the AV node), where there is a slight delay that allows the ventricle to fill before it contracts and pumps blood to the body. The signal continues throughout the ventricles and causes them to beat and push blood to the body.
What causes paroxysmal supraventricular tachycardia (PSVT)?

In paroxysmal supraventricular tachycardia (PSVT), abnormal conduction of that electricity causes the atrium, and secondarily the ventricles, to beat very rapidly. It is referred to as paroxysmal because the rapid rate can occur sporadically and without warning and may also stop on its own. The rapid heartbeat may last a few seconds or many hours. Often the PSVT resolves before the patient reaches a health care professional.
In many patients with PSVT, there is a “wiring” problem in the AV node and instead of having just one pathway for electricity to travel to the ventricle, there are two. This allows electricity to circle back and cause the atrium to beat more quickly than it should normally. PSVT is one of many electrical abnormalities that cause the atrium to beat too quickly. These abnormalities were once lumped together and called paroxysmal atrial tachycardia or PAT but, as more has been learned about the electrical wiring of the heart, the terminology has been updated to better reflect the specific abnormal rhythm.
Some examples include
- atrial tachycardia,
- multifocal atrial tachycardia,
- atrial fibrillation,
- atrial flutter, and
- Wolff-Parkinson-White (WPW) syndrome.
As well, there are numerous abnormalities in the AV node that cause rapid heartbeats and palpitations. PSVT and other electrical abnormalities located in the atrium or AV node should not be confused with ventricular tachycardia, which arises from the ventricle and is potentially life-threatening.
What are the symptoms of paroxysmal supraventricular tachycardia (PSVT)?
One of the most common symptom of PSVT is heart palpitations, often described as a "rapid heartbeat." There can also be a fullness in the throat that is associated with the rapid heartbeat.
Other symptoms include the following:
- Lightheadedness,
- Weakness and fatigue
- Shortness of breath
- Chest pressure
- Syncope (passing out)
The symptoms of PSVT usually occur while the heart is beating quickly, but the fatigue can persist after the heartbeat returns to normal. By its nature, PSVT is intermittent and its onset cannot be predicted. As well, once the heart starts to beat quickly, there is no way of predicting if and when it will return to normal rhythm on its own. Some patients are unaware that their heart is beating quickly and PSVT is found only when the patient presents for care and is found to have a rapid heartbeat.
How is paroxysmal supraventricular tachycardia (PSVT) diagnosed?
The diagnosis of PSVT is based upon interpretation of the heart rate monitor and electrocardiogram.
Sometimes the diagnosis is difficult because the rapid heart rate resolves before the patient presents for medical care. In these cases, where there is a recurrent pattern of palpitations, the healthcare professional may suggest monitoring the patient's heart rate and rhythm as an outpatient. A Holter monitor is a small device that can be worn for 24 or 48 hours that records every heartbeat and may give a clue as to the underlying cause of the palpitations.
A 30-day event monitor may also be considered, which gives a longer window to detect the rhythm. Again, a small monitor is worn, but with this device the patient triggers the recording when the palpitations begin. In some cases, specialized electrophysiology tests may be necessary to monitor the heart and try to reproduce abnormal rhythms.
For infrequent events, an implantable device (LINQ) can be placed just under the skin, and can scan for a month looking for rare rhythm changes.

SLIDESHOW
Heart Disease: Causes of a Heart Attack See SlideshowWhat is the treatment for paroxysmal supraventricular tachycardia (PSVT)?
There is a stepwise approach to treating the rapid heartbeat of PSVT.
Vasovagal maneuvers stimulate the vagus nerve and can slow the heart rate. Some options include holding one's breath and bearing down as if to have a bowel movement or splashing cold water on the face. A care professional might cautiously massage the carotid artery in the neck, but in older patients, there is a risk of stroke and this procedure is usually reserved for younger patients.
Depending upon the heart rhythm, medications can be injected intravenously to reset the AV node or to decrease heart muscle excitability. Adenosine is a short-acting medication that is commonly used as a first-line drug to treat PSVT. Other treatment options for other atrial tachycardias include calcium channel blockers, beta blockers, digoxin, and amiodarone.
If the PSVT does not convert with intravenous medication or if the patient has low blood pressure or complains of chest pain or shortness of breath, cardioversion may be required. This means that an electrical shock is given that resets the heart's electrical system to beat with a regular rate and rhythm.
Health News
- Women's Gymnastics Brings High Risk for Concussion
- Going Solo: Masturbation May Give Humans an Evolutionary Edge
- Longer Breastfeeding in Infancy, Better School Grades for Kids?
- Kids With ADHD, Behavior Issues Have Poorer Trajectories as Adults
- FDA Finalizes Limit on How Much Arsenic Can Be in Apple Juice
More Health News »
How can paroxysmal supraventricular tachycardia (PSVT) be prevented?
PSVT can result because of underlying medical conditions or because of foods and medications that are ingested. Caffeine, alcohol, and over-the-counter (OTC) cold medications that contain pseudoephedrine can stimulate and irritate the heart's electrical conduction system and precipitate an episode of PSVT. Decreasing or avoiding use of these chemicals completely may prevent PSVT. Electrolytes abnormalities can cause heart electrical irritability. Abnormal thyroid levels can also precipitate abnormal heart rhythms.
Medications can be used to minimize the recurrence of PSVT, including calcium channel blockers, beta blockers, or other antiarrhythmic medications.
If PSVT continues to recur, an electrophysiologic study (EPS) can be done by a cardiologist and the electrical system of the heart can be mapped. If abnormal tracts or short circuits are found, they can be ablated or destroyed with high frequency radio waves and hopefully, prevent future episodes of PSVT. This is often a highly effective modality for patients with recurrent episodes who don't wish to have to take long-term medication.
Health Solutions From Our Sponsors
REFERENCE:
Tintinalli, Judith E., et al. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th edition. McGraw-Hill Education, 2011.
Top Paroxysmal Supraventricular Tachycardia (PSVT) Related Articles
Heart Healthy Diet: 25 Foods You Should Eat
What foods are heart healthy? Learn what foods help protect your cardiovascular system from heart attack, coronary heart disease, stroke, and cardiovascular disease. Plus, find easy meal recipes and menu ideas for more everyday heart benefit.Atrial Fibrillation (AFib)
Atrial fibrillation (AF or AFib) is an abnormality in the heart rhythm, which involves irregular and often rapid beating of the heart. Symptoms may include heart palpitations, dizziness, fainting, fatigue, shortness of breath, and chest pain. Atrial fibrillation treatment may include medication or procedures like cardioversion or ablation to normalize the heart rate.Cancer
Cancer is a disease caused by an abnormal growth of cells, also called malignancy. It is a group of 100 different diseases, and is not contagious. Cancer can be treated through chemotherapy, a treatment of drugs that destroy cancer cells.Chest Pain
Chest pain is a common complaint by a patient in the ER. Causes of chest pain include broken or bruised ribs, pleurisy, pneumothorax, shingles, pneumonia, pulmonary embolism, angina, heart attack, costochondritis, pericarditis, aorta or aortic dissection, and reflux esophagitis.
Diagnosis and treatment of chest pain depends upon the cause and clinical presentation of the patient's chest pain.
Electrocardiogram (ECG or EKG)
An electrocardiogram is known by the acronyms "ECG" or "EKG" more commonly used for this noninvasive procedure to record the electrical activity of the heart. An EKG generally is performed as part of a routine physical exam, part of a cardiac exercise stress test, or part of the evaluation of symptoms. Symptoms evaluated include palpitations, fainting, shortness of breath, dizziness, fainting, or chest pain.Electrolytes
Electrolytes are substances that become ions in solution and acquire the capacity to conduct electricity. The balance of the electrolytes in our bodies is essential for normal function of our cells and our organs. Common electrolytes include sodium, potassium, chloride, and bicarbonate. The functions and normal range values for these electrolytes are important, and if an electrolyte is at an extreme low or high, it can be fatal.Electrophysiology Test
An electrophysiology (EP) study is a test that records the electrical activity and the electrical pathways of your heart. This test is used to help determine the cause of your heart rhythm disturbance and the best treatment for you. During the EP study, your doctor will safely reproduce your abnormal heart rhythm and then may give you different medications to see which one controls it best or to determine the best procedure or device to treat your heart rhythm.Fainting (Syncope): Guide to Causes, Symptoms, Treatment and Prevention
Fainting, also referred to as blacking out, syncope, or temporary loss of consciousness has many causes. Often a person will have signs or symptoms prior to the fainting episode. Diagnosis and treatment depends upon the cause of the fainting or syncope episode.Heart Detail Picture
The heart is composed of specialized cardiac muscle, and it is four-chambered, with a right atrium and ventricle, and an anatomically separate left atrium and ventricle. See a picture of Heart Detail and learn more about the health topic.Heart Disease: Causes of a Heart Attack
Heart disease prevention includes controlling risk factors like diet, exercise, and stress. Heart disease symptoms in women may differ from men. Use a heart disease risk calculator to determine your heart attack risk.Heart Disease Quiz
Take our Heart Disease Quiz to get answers and facts about high cholesterol, atherosclerosis prevention, and the causes, symptoms, treatments, testing, and procedures for medically broken hearts.Am I Having a Heart Attack? Symptoms of Heart Disease
Heart attacks symptoms vary greatly for men and women, from anxiety and fatigue to nausea and sweating. Learn the warning signs of a heart attack and know the symptoms that may require an immediate trip to the hospital.How the Heart Works
The heart is a very important organ in the body. It is responsible for continuously pumping oxygen and nutrient-rich blood throughout your body to sustain life. It is a fist-sized muscle that beats (expands and contracts) 100,000 times per day, pumping a total of five or six quarts of blood each minute, or about 2,000 gallons per day.High-Fiber Foods
Learn about high-fiber foods. From fresh fruits to whole grains, these fiber-rich foods can lower cholesterol, prevent constipation, and improve digestion.Low Blood Pressure (Hypotension)
Low blood pressure, also referred to as hypotension, is blood pressure that is so low that it causes symptoms or signs due to the low flow of blood through the arteries and veins. Some of the symptoms of low blood pressure include light-headedness, dizziness, and fainting if not enough blood is getting to the brain. Diseases and medications can also cause low blood pressure. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidneys; the organs do not function normally and may be permanently damaged.Radiofrequency Ablation (RFA) of the Liver
Radiofrequency ablation (RFA) of the liver is a technique used to treat liver cancer. RFA uses imagine procedures like CT scan, ultrasound, and MRI (magnetic resonance imaging) to guide the RFA probe into the area of the tumor. There are different ways to perform radiofrequency ablation. Side effects of radiofrequency ablation of the liver are pain after the procedure, injury to the bowel, and inflammation of the gallbladder. The procedure lasts approximately 10-30 minutes.