Supraventricular Tachycardia Treatment in Delhi, India

Supraventricular Tachycardia is a type of irregular heartbeat that causes the heart to beat rapidly, specifically affecting the upper chambers of the heart. 

It occurs in episodes that manifest as dizziness, low blood pressure, and other symptoms. Sometimes, the only noticeable sign is the rapid heartbeat. There is no single known cause of this condition, and it is often triggered by medical conditions or previous surgery. SVT usually affects younger people and is more common in women.

There are three main types of SVT: 

Atrioventricular nodal reentrant tachycardia (AVNRT)

AVNRT is the most common type of supraventricular tachycardia. It occurs due to the presence of the reentry circuit pathway near the atrioventricular node, causing a premature contraction to occur. This early contraction allows the electrical impulse to enter the circuit and circle repeatedly instead of moving down the lower chambers of the heart. This causes the rapid heartbeat that starts and stops abruptly. 

Atrioventricular reciprocating tachycardia (AVRT)

AVRT is the second most common type of SVT. It creates an extra connection between the lower and the upper chambers of the heart, forming an additional electrical loop. This condition results in more heartbeats than normal.

Atrial tachycardia

Atrial tachycardia is caused by a short circuit in the heart’s left or right atrium, which triggers a faulty electrical signal. It is most commonly seen in individuals with an existing heart condition.

Supraventricular tachycardia (SVT) is caused by faulty signalling in the heart, which prompts the heartbeat to start early in the heart's upper chambers, speeding up the herat rate. When this happens, the heart cannot fill with blood adequately between beats. 

Several factors may lead to a faulty signalling in the heart, including:

• Certain Conditions: Some health conditions such as lung disease, thyroid disease or a heart disease can speed up the pumping of the heart.
• Medications: Some medications, including those prescribed for allergies or asthma, can interfere with the normal functioning of the heart.
• Heart Surgery: A scar tissue, formed after surgery, can change the electrical signals.

Several factors increase the risk of developing SVT. These include:

• Sleep disorder
• Excessive alcohol consumption
• Smoking
• Emotional stress
• Excessive caffeine intake

The most common symptoms of SVT include:

• Rapid heartbeat
• Sweating
• Lightheadedness
• Chest Pain

In rare cases, SVT can cause unconsciousness or even cardiac arrest. Sometimes, SVT may not cause any symptoms at all. 

If you feel you or your loved one has any of these symptoms, consider consulting a doctor at Max, one of the best heart hospitals in India, for a timely diagnosis and intervention. 

Electrocardiogram 

During an ECG or EKG, electrodes are attached to the chest to check the heartbeat. The resulting graph indicates the heart’s rhythm and rate. 

Echocardiogram

Echocardiogram uses sound waves to generate images of the beating heart, helping to assess the function of the heart valves. Issues with the aorta, valves or the heart’s pumping ability can be detected through this method.

Holter Monitor

A Holter monitor is a small wearable device used when the ECG does not provide enough detail about the heart’s condition. Through this device, heartbeats are recorded over a period of 1-2 days.

Implantable Loop Recorder

A loop recorder is implanted under the skin, near the heart. It works as an ECG and picks up electrical signals from the heart and records anything abnormal. The loop recorder can monitor heart rhythms for up to 3 years, making it useful in cases where other tests have not identified a cause.

SVT is an episodic condition and doesn’t usually require treatment. But sometimes, the rapid heartbeats last longer and may need treatment. Treatment options for SVT are as follows:

Medications

Medications such as calcium channel blockers and beta blockers are typically prescribed by the doctor if SVT episodes occur frequently. These medications help keep the heartbeat in control. 

Vagal manoeuvres

Simple actions like applying an ice pack to the face or coughing can stimulate the vagus nerve and are enough to slow a rapid heartbeat. 

Catheter ablation

Catheter ablation is a procedure that threads thin flexible tubes (called catheters) through a vein to the heart. The catheter releases a pulse of heat or cold that breaks the abnormal electrical pathway causing an irregular heartbeat.

Cardioversion

In cases of emergency, a set of paddles or patches are used to deliver an electric shock to the heart. This helps bring the heartbeat back to normal. Cardioversion can also be performed using medications, a method known as chemical cardioversion.

Pacemaker

In rare cases, a device called a pacemaker can be surgically placed under the skin near the collarbone. This device sends small electrical impulses to the heart to help restore regular rhythm.

A common complication of SVT is heart failure. The rapid heartbeat may prevent the heart from sending enough blood to the body, leading to low oxygen levels in organs and tissues. In the long run, SVT can cause the heart to weaken, resulting in heart failure. In severe cases, an SVT attack can also lead to cardiac arrest.

One of the best ways to prevent SVT episodes is to modify your lifestyle a bit, that includes making the following changes:

• Eat a heart-healthy diet:  Incorporate more vegetables and fruits into the diet, as they are low in calories and rich in fibre. Whole grain foods are also good examples of high sources of nutrients and fibre. Oatmeal, barley, and brown rice are some options. 
• Limit caffeine consumption: Too much caffeine has been linked to trigger SVT episodes. So, it is best to avoid it.
• Keep a diary of episodes: Maintain a journal recording details of each episode, including heart rate, the possible triggers, and symptoms. Tracking patterns can be useful in identifying specific factors that may trigger SVT.

Can SVT happen during pregnancy?

Yes, the predispositions that cause the occurrence of supraventricular tachycardia may appear during pregnancy due to high levels of hormones, increase in blood volume, and increased workload on the heart. Consult a doctor if these symptoms occur during pregnancy.

How long does an SVT episode typically last?

Episodes may last from a few minutes to several hours. The duration of the episode varies depending on the person and the severity of the condition.

Can lifestyle changes completely prevent episodes of SVT?

Even though lifestyle changes like stress reduction, limiting caffeine and quitting smoking may reduce the frequency of episodes, they do not often suppress episodes altogether and treatment is thus eventually required.

How is SVT different from atrial fibrillation?

SVT involves rapid heartbeats originating from the upper chambers of the heart but typically having a regular rhythm. Atrial fibrillation involves irregular heartbeats, which are very rapid and chaotic. 

Can emotional stress trigger an episode of SVT?

Yes, a common cause of an episode of SVT is emotional stress. Stress management techniques, such as meditation and relaxation exercises, may reduce the likelihood of an episode.

Is SVT a serious condition?

SVT is usually not life-threatening, but severe or prolonged episodes can cause complications such as fainting; in rare instances, cardiac arrest has been reported. An episode that persists for a long time should be assessed by a doctor.

How is it different from ventricular tachycardia?

SVT is initiated within the upper chambers, or atria, of the heart, and VT is initiated within the lower chambers, or ventricles. VT can sometimes be more dangerous and needs immediate treatment.

Can SVT go away spontaneously or with no intervention?

Episodes of SVT can sometimes resolve by themselves. Recurrent episodes need drugs or catheter ablation as treatment options.

Can SVT cause blood clots?

SVT itself is not a cause of blood clots, however in conjunction with an intrinsic heart disorder or other predisposing condition, it may increase the risk of clotting.

Reviewed By Dr. Bipin Kumar Dubey, HOD-Cardiology & Principal Director - Interventional Cardiology, Cardiac Sciences, on 26 Dec 2024.