What Is Supraventricular Tachycardia?

Supraventricular tachycardia (SVT) is an abrupt or erratic (arrhythmia) heartbeat that mainly affects the upper chambers of your heart. SVT can also be called paroxysmal supraventricular tachycardia. The term SVT has two Latin roots. Supraventricular means “above the ventricles,” (lower sections of your heart) and tachycardia means “fast heart rate.”

Certain conditions are responsible for a faster heartbeat. By observing your symptoms and doing a physical exam, the doctor will record your heartbeats to ensure the diagnosis.

Though an abrupt heartbeat makes you scared, it doesn’t cause any serious health issues. Consult a doctor if your heart beats too fast. Sometimes, a sudden fall in pressure may make your heart beat faster. By prescribing medications and other treatments, your doctor will bring back a normal heartbeat.

How Does Your Heart Beats?

Your heart is a muscular organ that beats 100,000 times a day and sends oxygen-rich blood out to your body. The heart contains 4 pumping chambers. The left and right atria are at the top, and the left and right ventricles are at the bottom. Your heart also has a natural pacemaker which is called the sinoatrial node, or SA node. This is situated at the top of your heart and sends out electrical signals to keep the heart’s beating normal.

If you are at rest, your natural heartbeat is between 50 to 99 times a minute. The heart naturally enhances and reduces in speed based on signals that get sent to the SA node. But in the case of an SVT heart, these signals don’t occur normally.

What Is Supraventricular Tachycardia?

An SVT heart rate is more than 100 times a minute.

This condition is divided into three types:

Atrioventricular Nodal Reentrant Tachycardia: This is the most common of all. Under this condition, there is an add-on pathway in your heart that creates an electrical signal to circle around and around instead of moving down to the ventricles. This condition may stimulate a rapid heartbeat.

Atrioventricular Reciprocating Tachycardia:  This condition occurs when there is an extra pathway link between the atria and ventricles. This produces the signal to move around and around in a big loop.

If you are suffering from a genetic condition called Wolff-Parkinson-White syndrome, then you may have this extra pathway. Since this is a serious condition, hence you should check your family history first.

Atrial Tachycardia: This situation occurs when a short circuit has happened in the right or left atrium which triggers a faulty electrical signal.

Any of the above situations may last from a few seconds to a few hours. When SVT only happens from time to time, it’s called paroxysmal supraventricular tachycardia.

6 Causes Supraventricular Tachycardia

There are no particular reasons for SVT. It can even appear in your teens or early 20s. Sometimes you may possess abnormal pathways or electrical circuits in your heart by default.

• Your heart will beat faster
• If you consume excessive caffeine/alcohol
• If you smoke frequently
• If you take a lot of stress or are very tired
• If you take certain medications like asthma drugs, decongestants, and some herbal medications
• If you take drugs like cocaine or methamphetamine

4 Symptoms of Supraventricular Tachycardia

If your heart beats rapidly, then it doesn’t get adequate time to refill with blood in between beats. This means it can’t send sufficient blood out to your body. As a result, you may get:

• Chest Pain
• Dizziness
• Fatigue
• Shortness of breath

Diagnosis of Supraventricular Tachycardia

If you are experiencing symptoms, your doctor may ask some questions. These questions could be:

• Your age when you first observed a problem
• He may ask when and how your symptoms start
• Did you observe symptoms like rapid pulse, dizziness or difficulty in breathing during an exercise?

Other Questions About Supraventricular Tachycardia

• Whether the symptoms came on abruptly or gradually
• How long do these symptoms usually last
• If your heart beats faster after caffeine or stress
• Whether anyone in your family has had heart problems or procedures

During a physical exam, your doctor will check your heart and lungs with a stethoscope. He might also:

• Feel your thyroid gland on your neck
• Check your body temperature
• Measure your blood pressure
• Recommend some blood tests

EKG Test

After physical examinations and some basic blood tests, if your doctor suspects that you are having supraventricular tachycardia, then he might suggest an EKG test. This is also called an “electrocardiogram” or an ECG.

This test records the rhythm of your heart over time. The test also portrays what kind of problem you are having.

For this test, an experienced nurse or technician will attach six sticky patches called electrodes on your chest and others on your arms and legs. Each electrode has a wire that leads to a machine. During the test, you need to lie down and breathe normally.

Home Monitoring

Sometimes, a single EKG may not show an abnormal heart rate.

Thus, you need to wear a device for longer so doctors can monitor and record your heart while you are having symptoms.

• A Holter Monitor: This is a small and battery-driven EKG that records your heart’s activity for 24 to 48 hours. Apart from bathing, you can do other activities with this device.
• An Event Monitor: If you have symptoms less than once a day, then this portable ECG device could be your apt choice.  You can wear this device longer than a Holter and press a button when you are having symptoms.

Further Tests

To find out what type of SVT you have and its cause, you may need an “electrophysiology study” test. This test helps your doctor to know how different sections of your heart are sending electrical signals to each other.

SVT Treatments

Medications are recommended to slow the heartbeat.

If you are not getting better with medications, then ablation is used. In this treatment procedure, a surgeon burns pathways that are causing abnormal electrical signals.

The Bottom Line

SVT (supraventricular tachycardia) is a problem that is associated with your heartbeat’s speed or rhythm (arrhythmia). By doing simple lifestyle changes, you can prevent the symptoms of SVT. Sometimes, you may need medications to slow down the speed of your heart. Take the prescribed medications properly and do your follow-up appointments to regularize your heartbeat.