What is supraventricular tachycardia. How does SVT affect heart rhythm. What are the common symptoms of SVT. When should you seek medical attention for SVT. What treatments are available for managing SVT.

Understanding Supraventricular Tachycardia: A Rapid Heartbeat Condition

Supraventricular tachycardia (SVT) is a cardiac condition characterized by sudden episodes of abnormally fast heart rate. This occurs when the electrical system controlling the heart’s rhythm malfunctions, causing the heart to beat much faster than normal, typically exceeding 100 beats per minute (bpm) at rest.

SVT episodes can vary in duration and frequency, lasting from a few minutes to several hours. They may occur multiple times daily or as infrequently as once a year. While SVT can affect individuals of any age, it often first manifests in children and young adults, with many experiencing their initial symptoms between the ages of 25 and 40.

The Mechanics of SVT: How Does It Affect Heart Rhythm?

To understand SVT, it’s crucial to grasp the basics of normal heart function. The heart is a muscular organ comprising four chambers: two upper atria and two lower ventricles. A natural pacemaker called the sinoatrial (SA) node typically regulates the heart’s rhythm by sending electrical signals through specialized pathways.

In SVT, this electrical system malfunctions, causing rapid and often irregular heartbeats originating above the ventricles. This abnormal rhythm can interfere with the heart’s ability to pump blood efficiently, potentially leading to various symptoms and complications.

Types of Supraventricular Tachycardia

Several types of SVT exist, each with unique characteristics:

• Atrial Fibrillation (AFib): Rapid, irregular contractions of the atria
• Atrial Flutter: Rapid, regular contractions of the atria
• Atrioventricular Nodal Reentrant Tachycardia (AVNRT): Involves a “short circuit” in the AV node
• Wolff-Parkinson-White Syndrome: Presence of an extra electrical pathway in the heart

Recognizing SVT: Common Symptoms and Warning Signs

The primary symptom of SVT is a sudden, rapid heartbeat. However, individuals may experience a range of additional symptoms, including:

• Chest pain or discomfort
• Shortness of breath
• Lightheadedness or dizziness
• Weakness or fatigue
• Nausea or vomiting
• Palpitations or a fluttering sensation in the chest

Is SVT always symptomatic? Not necessarily. Some individuals may experience no symptoms other than the rapid heartbeat itself. However, the presence of additional symptoms often prompts individuals to seek medical attention.

Triggers and Risk Factors: What Causes SVT Episodes?

While the exact cause of SVT can vary among individuals, several factors may trigger episodes or increase the risk of developing the condition:

1. Stress and anxiety
2. Caffeine consumption
3. Alcohol intake
4. Smoking
5. Fatigue or lack of sleep
6. Certain medications
7. Hormonal changes (e.g., during pregnancy or menstruation)
8. Underlying heart conditions
9. Genetic predisposition

Can lifestyle changes help reduce SVT episodes? Indeed, making certain lifestyle modifications can potentially decrease the frequency and severity of SVT episodes. These may include reducing caffeine and alcohol intake, quitting smoking, managing stress, and ensuring adequate rest.

Diagnosing SVT: Tools and Techniques Used by Medical Professionals

Accurate diagnosis of SVT is crucial for effective management. Healthcare providers employ various tools and techniques to identify and characterize the condition:

• Electrocardiogram (ECG): Records the heart’s electrical activity
• Holter Monitor: A portable ECG device worn for 24-48 hours
• Event Recorder: A wearable device activated during symptoms
• Electrophysiology Study: An invasive test to map the heart’s electrical system
• Tilt Table Test: Assesses how blood pressure and heart rate respond to position changes

Why is proper diagnosis important for SVT management? Accurate diagnosis allows healthcare providers to determine the specific type of SVT and develop an appropriate treatment plan tailored to the individual’s needs.

Treatment Options: Managing SVT Effectively

The management of SVT varies depending on the frequency and severity of episodes, as well as individual patient factors. Treatment options include:

1. Lifestyle Modifications

For mild cases, lifestyle changes may be sufficient to manage SVT:

• Stress reduction techniques (e.g., meditation, yoga)
• Avoiding known triggers
• Maintaining a healthy diet and exercise routine
• Limiting caffeine and alcohol consumption

2. Vagal Maneuvers

Simple techniques to stimulate the vagus nerve and potentially stop an SVT episode:

• Valsalva maneuver (bearing down as if having a bowel movement)
• Carotid sinus massage (under medical supervision)
• Facial immersion in cold water

3. Medications

Various medications can be prescribed to control SVT:

• Beta-blockers
• Calcium channel blockers
• Antiarrhythmic drugs

4. Cardioversion

For persistent SVT episodes, cardioversion may be necessary:

• Electrical cardioversion: Delivers a controlled electric shock to reset the heart’s rhythm
• Chemical cardioversion: Uses intravenous medications to restore normal rhythm

5. Catheter Ablation

A minimally invasive procedure to correct the heart’s electrical pathways:

• Thin tubes (catheters) are inserted through blood vessels to the heart
• Radiofrequency energy or extreme cold is used to destroy problematic tissue
• High success rate in permanently curing SVT in many patients

How effective is catheter ablation for treating SVT? Catheter ablation has shown high success rates, with many patients experiencing a permanent cure for their SVT. However, the procedure’s effectiveness can vary depending on the specific type of SVT and individual patient factors.

Living with SVT: Long-term Management and Prognosis

While SVT can be a concerning condition, it is generally not life-threatening. With proper management and treatment, most individuals with SVT can lead normal, active lives. Long-term management strategies may include:

• Regular follow-up appointments with a cardiologist
• Continuous monitoring of heart rhythm and overall cardiovascular health
• Adherence to prescribed medications and treatment plans
• Maintaining a heart-healthy lifestyle
• Being prepared for potential SVT episodes with an action plan

Can SVT resolve on its own? In some cases, particularly in children and young adults, SVT may resolve spontaneously over time. However, for many individuals, ongoing management or definitive treatment like catheter ablation may be necessary for long-term control of the condition.

When to Seek Medical Attention: Recognizing SVT Emergencies

While most SVT episodes are not immediately life-threatening, certain situations warrant prompt medical attention:

• SVT episodes lasting longer than 30 minutes
• Sudden shortness of breath accompanied by chest pain
• Loss of consciousness or severe dizziness
• Persistent symptoms despite attempting vagal maneuvers

In these cases, individuals should seek emergency medical care immediately. Healthcare providers can administer appropriate treatments to restore normal heart rhythm and prevent potential complications.

What should you do if you suspect you’re experiencing an SVT episode? If you believe you’re having an SVT episode, try performing a vagal maneuver like the Valsalva technique. If symptoms persist or worsen, contact your healthcare provider or seek emergency medical attention, especially if you experience severe symptoms or the episode lasts longer than 30 minutes.

Research and Future Directions in SVT Management

Ongoing research in the field of cardiac electrophysiology continues to advance our understanding and treatment of SVT. Some areas of focus include:

• Improved mapping techniques for more precise catheter ablation procedures
• Development of new antiarrhythmic medications with fewer side effects
• Investigation of genetic factors contributing to SVT susceptibility
• Exploration of novel non-invasive treatments for SVT

As research progresses, individuals with SVT can look forward to potentially more effective and less invasive treatment options in the future.

How might future advancements impact SVT treatment? Emerging technologies and treatment modalities may lead to more personalized approaches to SVT management, potentially improving outcomes and quality of life for individuals living with the condition.

Supraventricular tachycardia (SVT) – NHS

Supraventricular tachycardia (SVT) is a condition where your heart suddenly beats much faster than normal. It’s not usually serious, but some people may need treatment.

Causes of supraventricular tachycardia (SVT)

SVT happens when the electrical system that controls your heart rhythm is not working properly.

This causes your heart to suddenly beat much faster. It can then slow down abruptly.

A normal resting heart rate is 60 to 100 beats per minute (bpm). But with SVT your heart rate suddenly goes above 100bpm. This can happen when you’re resting or doing exercise.

Symptoms of supraventricular tachycardia (SVT)

Having SVT means your heart suddenly beats faster.

This:

• usually lasts for a few minutes, but can sometimes last for several hours
• can happen several times a day or once a year – it varies
• can be triggered by tiredness, caffeine, alcohol or drugs – but often there’s no obvious trigger
• can happen at any age, but often starts for the first time in children and young adults – many people have their first symptoms between 25 and 40

You may get no other symptoms, but sometimes people also:

• have chest pain
• feel weak, breathless or lightheaded
• feel tired
• feel sick or are sick

Non-urgent advice: See a GP if you keep getting a fast heartbeat

It’s important to get it checked out. You might need a test, such as an electrocardiogram (ECG), to find out what’s going on.

Immediate action required: Call 999 or go to A&E if:

• you have been diagnosed with SVT and your episode has lasted longer than 30 minutes
• you have sudden shortness of breath with chest pain

You need to go to hospital for treatment immediately.

Things you can do to help with supraventricular tachycardia (SVT)

If your episodes of SVT only last a few minutes and do not bother you, you may not need treatment.

You can make changes to your lifestyle to reduce your chances of having episodes, such as:

• cutting down on the amount of caffeine or alcohol you drink
• stopping or cutting back on smoking
• making sure you get enough rest

Your doctor may also be able to recommend some simple techniques to help stop episodes when they happen.

Treating supraventricular tachycardia (SVT) in hospital

SVT is rarely life threatening. But you may need treatment in hospital if you keep having long episodes.

This may include:

• medicines to control the episodes of SVT – given as tablets or through a vein
• cardioversion – a small electric shock to the heart to help it get back to a normal rhythm
• catheter ablation – a treatment where thin tubes are placed through a vein or artery into your heart to correct the problem with the electrical system; this permanently cures the problem in most patients

Find out more about:

• cardioversion: British Heart Foundation
• catheter ablation: British Heart Foundation

Page last reviewed: 27 April 2021
Next review due: 27 April 2024

Types, Causes, & Risk Factors

Written by WebMD Editorial Contributors

• How Your Heart Beats
• What Is Supraventricular Tachycardia?
• Causes
• Symptoms
• Diagnosis
• Treatments
• More

Sometimes, a problem with your heart’s electrical signals can make it speed up, even when you’re not anxious or exercising. One type of faster-than-normal heartbeat is called supraventricular tachycardia (SVT).

SVT is a group of heart conditions that all have a few things in common.

The term has Latin roots. Supraventricular means “above the ventricles,” which are the lower two sections of your heart. Tachycardia means “fast heart rate.”

Other conditions can cause your heart to beat too fast. Your doctor will need all the details of your symptoms. They’ll also do a physical exam and record your heartbeats to be sure of the diagnosis.

Most of the time, it doesn’t cause any serious health problems even though a racing heartbeat can be a scary feeling. Still, you should see your doctor about it. When your heart beats too quickly, it can’t pump out enough blood to meet your body’s needs.

Sometimes you might have a drop in blood pressure and feel dizzy or lightheaded. Other times, the only feeling is the rapid heartbeat.

Your doctor can try to bring your heart back into a regular rhythm with medicines and other treatments.

Your heart is a muscular organ that pumps about 100,000 times a day to send oxygen-rich blood out to your body. It has four pumping chambers to do the job. The left and right atria are at the top, and the left and right ventricles are on the bottom.

Your heart also has something of a natural pacemaker. It’s called the sinoatrial node, or SA node, for short. It’s at the top of the heart and sends out electrical signals that keep it beating the right way.

The electrical signal from the SA node makes the muscles of the atria contract to pull blood into the ventricles. Then the signal moves down and causes the muscles of the ventricles to squeeze. That causes blood to go out to the body.

The heart beats like this in a familiar lub-dub pattern some 50 to 99 times a minute if you’re at rest.

The heart normally increases and decreases in speed based on signals that get sent to the SA node. During a bout of SVT, these signals do not occur normally.

Tachycardia is a faster-than-normal heart rate at rest. If you have this condition, your heart beats too quickly — more than 100 times a minute. The “supra” in supraventricular means above the ventricles.

With this condition, the fast heartbeat starts in the top chambers of the heart, the atria. When electrical signals in the atria fire off early, the atria contract too soon. That interrupts the main electrical signal coming from the SA node. This results in the heart beating very quickly through an abnormal and separate pathway.

This condition is divided into three types:

Atrioventricular nodal reentrant tachycardia is the most common form. If you have it, there’s an extra pathway in your heart that causes an electrical signal to circle around and around instead of moving down to the ventricles. This can trigger the rapid heartbeat.

Atrioventricular reciprocating tachycardia happens when an abnormal pathway links the atria and ventricles, causing the signal to move around and around in a big loop.

If you have the inherited condition called Wolff-Parkinson-White syndrome, you have this extra pathway. This condition can be serious. If it is part of your family history, have it checked.

Atrial tachycardia happens when a short circuit in the right or left atrium triggers a faulty electrical signal.

Bouts of any of these can last from a few seconds to a few hours. When SVT only happens from time to time, it’s called paroxysmal supraventricular tachycardia.

Most of the time, SVT happens without any obvious reason. It often starts when you are in your teens or early 20s.

Sometimes you are born with abnormal pathways or electrical circuits in your heart. Faulty circuits can also form out of scar tissue left behind after surgery.

Your heart is more likely to race if you:

• Drink a lot of caffeine and/or alcohol
• Smoke
• Are under a lot of stress or are very tired
• Take certain medicines, such as asthma drugs, decongestants, and some herbal diet remedies
• Take drugs such as cocaine or methamphetamine, also called crystal meth

When your heart beats too quickly, it doesn’t have time to fully refill with blood in between beats. That means it can’t send enough blood out to your body. That can cause:

• Chest pain
• Dizziness
• Fatigue
• Shortness of breath

If you have symptoms, your doctor will ask you detailed questions.

They’ll want to know how old you were when you first noticed a problem. They’ll also ask when and how your symptoms began. That includes whether you were exercising when you noticed things such as a rapid pulse, dizziness or a hard time breathing.

Other things they’ll ask you about:

• Whether the symptoms came on suddenly or slowly
• What they feel like to you and how long they tend to last
• Whether you’ve noticed that you’ve had a fast heartbeat after caffeine or stress
• Whether you or anyone in your family has had heart problems or procedures

During your exam, your doctor will listen to your heart and lungs with a stethoscope. They might also:

• Feel your thyroid gland on your neck
• Get your temperature and measure your blood pressure
• Take a small blood sample with a thin needle

EKG test

If your doctor suspects supraventricular tachycardia after hearing about your symptoms, examining you and running some basic tests, they might ask you to get an EKG. You may hear them call it an “electrocardiogram” or an ECG.

This test records your heart’s rhythm over time, so if it’s not beating as it should, it can reveal what the problem is. If you’re getting one, there’s nothing special you need to do ahead of time to get ready.

To set up the test, a nurse or technician will attach six sticky patches called electrodes on your chest and others on your arms and legs. If you have a hairy chest, an aide may need to shave small areas so they stay put.

Each one will go with a wire that leads to a machine. During the test, which takes just a few minutes, you’ll be asked to lie still and breathe normally.

Home monitoring

You might have symptoms just once in a while, so a single EKG in the doctor’s office may not reveal an abnormal heart rate.

In these cases, you might need to wear a device for longer so doctors can record your heart while you’re having symptoms. You may be sent home with one of the following:

A Holter monitor is a small, battery-powered EKG that records your heart’s activity for 24 to 48 hours. The device is about the size of a small camera and has little electrodes placed on your chest while you wear it. You can do most of your daily activities, but you shouldn’t bathe or shower.

An event monitor is also a portable EKG but might be more practical if you have symptoms less than once a day. You can wear it for longer than a Holter and press a button on it when you’re having symptoms. The monitor will record details only for the few minutes you’re feeling the fast heartbeat.

Your doctor may ask you to wear it for days or weeks.

Further tests

If you’re diagnosed based on the results of an EKG, you may need more tests to figure out what type of SVT you have and what’s causing it.

Often, this can include what’s called an “electrophysiology study” so that doctors can learn in more detail how the different sections of your heart are sending electrical signals to each other.

For this test, you are sedated at a hospital or clinic and soft, flexible wires are passed through your veins into your heart. You will need someone to drive you to and from your appointment. Talk to your doctor about how to prepare because this test is more involved.

One treatment for SVT uses medicine to slow the heartbeat.

If that doesn’t fix the problem for you, another option is called ablation. In this procedure, a surgeon burns the pathway that causes the abnormal electrical signals.

If you feel like your heart is fluttering and you have any of the symptoms listed above, make an appointment with your doctor to be tested.

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Supraventricular tachycardia (SVT) | First Clinical Medical Center

Supraventricular tachycardia (SVT) is a condition in which the heart suddenly begins to beat much faster than normal. It is usually not serious, but some people may need treatment.

Causes of supraventricular tachycardia (SVT)

SVT occurs when the electrical system that controls the heart’s rhythm is not working properly.

This causes the heart to suddenly start beating much faster. Then it can slow down dramatically.

The normal resting heart rate is 60-100 beats per minute (bpm). But in SVT, the heart rate suddenly rises above 100 beats per minute. This can happen when you are resting or exercising.

Supraventricular tachycardia (SVT) symptoms

Supraventricular tachycardia means that your heart suddenly starts beating faster.

This is:

• usually lasts a few minutes but can sometimes last several hours
• may occur several times a day or once a year – it depends on the situation
• may be triggered by fatigue, caffeine, alcohol or drugs – but often no obvious cause
• can occur at any age, but often first begins in children and young adults—many people have their first symptoms between the ages of 25 and 40.

You may not have any other symptoms, but sometimes people with this condition also:

• experiencing chest pain
• feel weak, short of breath or dizzy
• feeling tired
• feeling unwell or sick

Important tip: see your doctor if you have a fast heartbeat.

It is important to get tested. You may need a test, such as an electrocardiogram (ECG), to find out what’s going on.

Call an ambulance immediately if:

• you are diagnosed with SVT and the attack lasts more than 30 minutes
• you have sudden shortness of breath with chest pain

You need to go to the hospital immediately for treatment.

What you can do to help with supraventricular tachycardia (SVT)

If your SVT attacks last only a few minutes and don’t bother you, you may not need treatment.

Disease Prevention

You can make lifestyle changes to reduce the chance of seizures, such as:

• reduce the amount of caffeine or alcohol you drink
• stop or reduce smoking
• make sure you get enough rest.

Your doctor can also give you some simple methods to help stop seizures when they happen.

Treatment of supraventricular tachycardia (SVT) in hospital

Supraventricular tachycardia is rarely life threatening. But you may need treatment in the hospital if you continue to have prolonged seizures.

This may include:

• medicines to treat SVT attacks – pills or by vein
• cardioversion – a small electric shock to the heart to help it return to a normal rhythm
• catheter ablation, a procedure in which thin tubes are inserted through a vein or artery into the heart to correct an electrical problem; in most patients, this solves the problem permanently.

Management of patients with supraventricular tachyarrhythmias

Oksana Mikhailovna Drapkina Professor, Doctor of Medical Sciences:

– The next lecture – Professor Olga Nikolaevna Miller, “Tactics of managing patients with supraventricular tachyarrhythmias. ”

Olga Nikolaevna Miller Doctor of Medicine, Professor:

– Good afternoon, dear colleagues! We are really going to talk about supraventricular tachyarrhythmias today. And first of all, I want to present this clinical and electrocardiographic classification, according to which, in fact, we, all cardiologists-arrhythmologists, have been working since 2006. It has been somewhat changed, indeed, since 2006, and you see that they distinguish the so-called sinoatrial reciprocal tachycardia (or re-entry tachycardia). The group of cardiac arrhythmias of atrial origin has slightly decreased – you see, only two types of cardiac arrhythmias are left in brackets: this is focal and multifocal, or, as we also call it, chaotic atrial tachycardia. A very large group of atrioventricular tachycardias, which includes AV nodal reciprocal tachycardia associated with the presence of additional pathways. And, undoubtedly, what is being very widely discussed today are two cardiac arrhythmias, in particular of supraventricular origin: atrial fibrillation and atrial flutter. We will not discuss them today, but, indeed, the whole world is discussing this problem, and not only “how to treat?”, “how to stop?”, “how to prevent?”, but also discusses antithrombotic therapy very widely.

So we’ll start with relief and of course we’re talking about the prevention of these supraventricular tachyarrhythmias. And first: if we have a patient with reciprocal tachycardia in front of us, that is, if it is supraventricular tachycardia caused by the re-entry mechanism, then there are no problems to stop it with the help of transesophageal pacing. Of course, endocardial can also be used, but this is mainly carried out in the arrhythmological departments during surgical interventions, for example, during radiofrequency ablation. Basically, in all hospitals, at least those who own these techniques, it is transesophageal cupping that is performed. You can use it as slow, competitive, fast, or super-fast pacing. And on these two fragments you can see how sinus rhythm was restored with a volley of impulses, where there is an effect on AV-nodal tachycardia on the upper film, and below is orthodromic tachycardia, again a volley of impulses, restoration of sinus rhythm. And you see perfectly well that in the sinus rhythm there are signs of pre-excitation, pre-excitation, that is, a short PQ interval, a delta wave, and a somewhat widened QRS complex.

Let’s see: if there is no way to stop the tachycardia, how should we treat if we really made the right diagnosis? So, sinoatrial reciprocal tachycardia. It is clear that it is due to the re-entry mechanism, and therefore the first thing you can do is to apply vagal maneuvers. You can use anything: squatting, inducing a gag reflex, a Valsalva test, that is, a breath-holding test. Best of all, of course, carotid sinus massage helps. I remind you that Ashner’s maneuver or Ashner’s test is prohibited today, this pressure on the eyeballs is not recommended to restore sinus rhythm.

You can use ATP. I will not talk about Adenosine, because Adenosine has never been on the pharmaceutical market of the Russian Federation, but you can introduce ATP in a dose of 10-20 milligrams. It is administered very quickly, as a bolus, as it is written. But bolus is sometimes a loose concept. Just a reminder that ATP is really injected very quickly, within 1-2 seconds, and without dilution.

You can use Verapamil. Its dose can be 5 or 10 milligrams, it is administered no faster than 2 minutes, so as not to get severe hypotension against the background of the administration of this drug.

The following drugs may be used: Digoxin, beta-blockers, Amiodarone are listed here. Digoxin has an advantage in the elderly. Of course, we understand that Digoxin does not belong to antiarrhythmic drugs, if we take into account the Williams classification, but, nevertheless, sometimes Digoxin helps in the relief of supraventricular tachyarrhythmias. I’m not talking about, I repeat, atrial fibrillation and flutter.

If your patient with sinoatrial reciprocal tachycardia already has hemodynamic disturbances, then, of course, electrical cardioversion is performed here. And I would like to draw your attention to the fact that the discharge power during electrical cardioversion should be small. At least 50 joules is enough to restore sinus rhythm.

And, of course, as I have already shown, pacing, which stops reciprocal tachycardia in 100% of cases.

The second question is how to warn? And you see the first sentence that there are no controlled studies on the prevention of sinus reciprocal tachycardia. In general, of course, if it is hemodynamically poorly tolerated or ineffective antiarrhythmic therapy, catheter ablation should be performed. But here surgeons must work very delicately, very carefully, because if they act on the sinoatrial zone powerfully, they can damage the sinus node, and then the second point of surgical intervention is the implantation of a pacemaker.

You can take medicines, ie tablets, to prevent episodes of sinus reciprocal tachycardia. It’s Verapamil, beta-blockers, just please titrate to the maximum tolerated. In elderly patients, you can use Digoxin, and also, but only as a last resort, you can use Amiodarone or Sotalol. Once again I repeat – in tablets. Why amiodarone last? Because amiodarone, we have repeatedly said about this, has a very high organotoxic effect.

The second thing that was presented on the electrocardiographic classification of supraventricular tachyarrhythmias is focal atrial tachycardia. And we must also understand that this is a focus that is located in the conduction system or in the atrial myocardium. Focal atrial tachycardia is not stopped by ATP, is not stopped by vagal techniques and is not treatable by pacing.

If your patient is hemodynamically stable, please slow down the heart rate in this situation. What can be used? You can apply Verapamil or Diltiazem, as well as beta-blockers.

It has been shown in some studies that first class A drugs have a good relief effect, but this is about relief. Of the drugs of the first A class on the pharmaceutical market of the Russian Federation, only the only drug is Novocainomid, although you can use it. The first class C is a good drug Propafenone, but, unfortunately, we do not have it in injectable form. You can try the third class drug – this is Kordaron.

If your patient has a low ejection fraction or there are clear signs of increasing heart failure, then in no case should you interfere with drugs of the first A, first C class.

And again, in case of hemodynamic disturbances – electrical cardioversion, and the discharge power – I emphasize again – is low, not 360 joules, but only 50-100 joules is enough to restore sinus rhythm.

How to warn? Try to start the prevention of this atrial tachycardia with beta-blockers, but I repeat – do not stop at a frozen dose. Titrate, select specifically for each patient this dose of beta-blockers. If there is no effect, use drugs of the fourth class of antiarrhythmics. And if both groups of drugs do not help, then you can use Amiodarone and Sotalol. Even if these drugs do not help and there is no possibility at the moment, for example, to perform radiofrequency ablation of this ectopic focus, then a combination of drugs can be tried. In particular, what drugs are welcome? These are first A or first C class drugs in combination with beta-blockers or calcium channel blockers, that is, with Verapamil.

Strictly speaking, if we take this algorithm for preventive therapy for focal atrial tachycardia, then the therapist or cardiologist has a lot of opportunities.

But multifocal atrial tachycardia – unfortunately, you see the first line: it says that the treatment of the underlying disease occupies an important place. Yes, we really understand that the cause of multifocal atrial tachycardia is most often COPD with exacerbations, the same bronchial asthma, multifocal tachycardia can occur in long-term febrile patients, in patients with a severe functional class of chronic heart failure and with severe diabetes mellitus.

And so, of course, we will first of all deal with slowing down the heart rate. And for this purpose, you can use Verapamil or beta-blockers, but it is clear that the latter are contraindicated due to exacerbation of COPD.

Amiodarone may be used, but also remember that with the introduction of Amiodarone in patients with COPD, broncho-obstructive syndrome may develop.

Cases of successful restoration of the rhythm with the help of magnesium sulfate are described, that is, when you inject a 25% solution of magnesium sulfate at a dose of 2 grams, which is 8-10 milliliters of this drug, and no faster than 3-5 minutes, you can restore the sinus rhythm. You can repeat after 5-10 minutes exactly the same dose.

Further written: first class C drugs, in particular Propafenone, are effective. But, once again, due to the lack of an injectable form, we cannot currently use this drug.

But electrical impulse therapy or electrical cardioversion, pacing with multifocal atrial tachycardia is ineffective. There are many ectopic foci, and therefore I once again pay attention to the first line – it is the treatment of the underlying disease that occupies an important place.

AV nodal reciprocal tachycardia. It used to be thought that it could develop for no particular reason. Today, if there is no coronary heart disease, sinus node weakness syndrome, any pathological changes in the area of ​​the atrioventricular junction, then this is a manifestation of connective tissue dysplasia syndrome. I won’t stop there.

Let’s see how to stop AV nodal tachycardia. Of course, the number one drug is calcium channel blockers, of course, that is, Verapamil. The effectiveness of Verapamil and this group of drugs is 95%, according to some sources even 98%. In the same line, beta-blockers and Digoxin are still written. But remember that the effectiveness of beta-blockers is low, only 50%, and Digoxin shows its antiarrhythmic effect in this type of heart rhythm disturbance only by the second hour.

If you are treating a patient without structural heart disease, meaning that the ejection fraction is sufficient, there is no problem. You can use Propafenone if it is in injectable form, and in 2013 representatives of the PRO. MED. Prague still promise that it will be on our pharmaceutical market.

In most cases, as it is written in all recommendations, Amiodarone and Sotalol are not used. Of course, it will not be a mistake if you enter the same Amiodarone. No one has ever seen sotalol in injections. Of course, it will not be a mistake whether you stop or do not stop this AV-nodal reciprocal tachycardia.

But further it says that class IA drugs are used to a limited extent. Why? Because Novokainomid, which exists in injections, unfortunately, has a vagolytic effect on the atrioventricular junction, and having, for example, tachycardia with a frequency of 160 per minute. And by introducing Novokainomid, you can get the same type of tachycardia, but it will already go with a frequency, for example, 180-200. Vagolytic action, that is, the acceleration of the movement of the impulse along this vicious circle. Well, or, of course, pacing in 100% of cases will stop reciprocal tachycardia.

What else do I want to remind you? That beta-blockers should not be administered in combination with Verapamil, Diltiazem or rapidly one after the other, because this can lead to severe bradycardia and even asystole. And in this regard, I would like to recall the expression of Richard Fogoros, who in his book “Antiarrhythmic drugs” wrote back in 1999 that the idea of ​​antiarrhythmic drugs as a “softening balm” is not only naive, but even dangerous. For if one takes this view of antiarrhythmic drugs as a “softening balm”, then in the case when the arrhythmia does not respond to a certain remedy, what does the doctor do? Either he naturally increases the dose of the same drug, or, even worse – I want to emphasize, Richard Fogoros correctly writes – he adds another drug. Not a single ambulance doctor will write a remark in the accompanying coupon if he injected a drug, did not stop tachycardia, if the patient’s hemodynamics are stable, bring him to the hospital, then we will deal with all this and try to stop this type of tachycardia.

What else needs to be remembered? If, with AV nodal reciprocal tachycardia, the ejection fraction is low or there are obvious manifestations of heart failure, realizing that Verapamil has a 98% efficiency, either Amiodarone or Digoxin should be used here. Do not forget that Verapamil does have a negative inotropic effect and in this situation, despite such high efficiency, it is contraindicated.

If you meet with AV nodal reciprocal tachycardia, the patient has low blood pressure numbers. Yes, indeed, it is described in the literature that vozopressors can interrupt such tachycardia. Because of which? Due to a reflex increase in vagus tone when trying to raise blood pressure numbers. We are talking, of course, about Mezoton, a 1% solution that you can enter with arrhythmic collapse or severe hypotension at a dose of 0.1-0.2 milliliters.

How is it prevented? And, in fact, there are no large clinical studies on the prevention of AV nodal reciprocal tachycardia. Abroad, these are mainly surgical interventions. And you see, some drugs were compared, and in fairly high doses. Pay attention to the dose of Digoxin, Verapamil, Propranolol – they had the same effectiveness. As for Propafenone – it is effective in 80% of cases – I will show one more graph in general on the effectiveness of drugs.

Next is the oral administration of amiodarone and the dose, you see, maintenance was 200-400 milligrams, for 66 days prevented seizures in all patients. I put three question marks on purpose because I found this study. There were 17 patients in total in the study. Of course, there is no evidence base here. But, nevertheless, I repeat once again that basically such patients are taken for surgical treatment.

If it is not possible to carry out surgical treatment, then with a reduced ejection fraction, of course, and with a severe functional class of CHF, Amiodarone should be used.

Some antiarrhythmics that are listed in this table (and you see – the years 1987, 1999 and the last year – 2008) prevent AV-nodal reciprocal tachycardia well, in particular, we have Propafenone in Propanorm tablets. With AV-nodal reciprocal tachycardia, what was discussed now is up to 80%, in no way inferior to either Sotalol or Amiodarone.

Another study by our Russian authors – Professor Bunin and co-authors, 2010 – showed that Propanorm as a representative of the first C class is quite good – you see, 75% and 81% – prevents both focal atrial tachycardia and AV nodal reciprocal tachycardia; and AV reciprocal tachycardia associated with an accessory pathway. Very good efficacy of this drug.

The next type of tachycardia, which I wanted to talk about very briefly, is the so-called orthodromic tachycardia – tachycardia associated with additional pathways. How to stop orthodromic tachycardia, that is, tachycardia with narrow complexes? The first point is occupied by all these drugs. Without re-reading everything, I can simply say that any antiarrhythmic drug for narrow complex tachycardia, except drugs of the first B class: except the Lidocaine class. That is, drugs of the first A class can be used, drugs of the first C class, beta-blockers that affect the atrioventricular node. We don’t care where to break this circle of re-entry: either to act on the accessory pathway, or on the atrioventricular junction. These are antiarrhythmics of the third class, and, of course, Verapamil preparations.

As for the tablets, it says here: the combination of Diltiazem and Propranolol was 94% effective. But if you have never tried to use this combination, for the first time yourself, you must definitely under the supervision of your doctor, then just do not recommend this combination of drugs to the patient. Moreover, this combination, you see – 94%, turned out to be even more effective than the use of the first class C drug, in particular, we are talking about Flecainide.

And, of course, transesophageal pacing, because orthodromic tachycardia is AV reciprocal tachycardia. I repeat once again: all reciprocal tachycardias lend themselves very well to stopping.

In terms of prophylactic therapy, you see this percentage of how well antiarrhythmic drugs work. A good drug, you see, Sotalol, Propafenone, Flecainide, and 100% – I am always confused by 100% in general in medicine, and even more so in arrhythmology – but, nevertheless, the combination is not bad: Propafenone (Propanorm) + beta-blockers – 100% . Again, when you open this study, you will see that there were 27 or 26 patients in total in the study. Basically, if we have a patient with additional atrioventricular connections – of course, this is radiofrequency ablation of these additional pathways.

Another small piece is atrial fibrillation plus extra pathways. We quite often see such cardiograms, very ugly. If you look at this cardiogram, it will remind you very much of monomorphic ventricular tachycardia. But we will see a clear inequality of RR intervals. Yes, the QRS complexes are wide, but there is a clear disparity in RR intervals, because if it were monomorphic ventricular tachycardia, there could be a disparity, but it is delicate, it should not be more than 0.02 seconds, that is, no more than 20 milliseconds . Here we see the usual atrial fibrillation, but, unfortunately, the reset of impulses goes through the patient’s additional path. Therefore, such an ugly film. And if you see a patient with such an electrocardiogram, in addition to what we will discuss now, how to stop such a tachycardia, immediately tell the patient: “You must definitely contact the surgical clinic.”

So what to stop? With a wide QRS complex, only three drugs are indicated: Propafenone, Amiodarone and Novokainomid (it is called Procainomid abroad).

Of course Digoxin should be avoided, but in WPW syndrome we all know about Digoxin – by no means. Verapamil with wide complexes is impossible, Lidocaine is impossible, as well as beta-blockers. Why? I will return once more to this film. Imagine that you, as a doctor, mistook this heart rhythm disorder for ventricular tachycardia. It is good that at the moment the priority in the relief of ventricular tachycardia is occupied by Amiodarone. But if you still love and give primacy to Lidocaine as, from your point of view, a safer drug, imagine that you will inject Lidocaine into this atrial fibrillation with conduction through an additional pathway. You will simply get the death of the patient. Therefore, we know about Digoxin, Verapamil, and, of course, do not forget about beta-blockers. But you may ask: “Why does Lidocaine sound here?” It was not for nothing that I returned to this film to show this feature.

How to prevent while the patient is on the waiting list for radiofrequency ablation? What is used? Good, excellent drug Propafenone (Propanorm), you can prescribe Amiodarone or Sotalol. But I repeat once again: due to the high frequency of organotoxic effects from Amiodarone, still try to use it as a last resort, especially if the patient is scheduled for surgery. Sometimes long-acting drugs – we are talking about Amiodarone – can interfere with surgeons during electrophysiological studies and surgical intervention.

Why are first class A drugs not being used? Because they do affect the accessory pathway, but they do not affect conduction through the normal atrioventricular conduction system. Why is Verapamil not used with beta-blockers? They, on the contrary, affect the atrioventricular connection and practically do not affect conduction in the accessory pathway. So, Propafenone (Propanorm), Amiodarone, Sotalol, which kill two birds with one stone: they both inhibit the conduction of excitation through the atrioventricular system and affect the additional pathway.

If a patient has chronic heart failure, but preserved systolic function – I always emphasize this too, that is, we are talking about diastolic dysfunction, that is, if the ejection fraction is preserved – combined antiarrhythmic therapy can be used. Yes, of course, we treat the underlying disease, where we use the main basic drugs, including beta-blockers, and if titrated, selected doses of beta-blockers do not help, then you can add Propafenone (Propanorm) to beta-blockers. A combination of Propafenone + Verapamil is possible in the absence of again pronounced manifestations of heart failure. And, if there is no effect from other combinations, a combination of Propafenone + Amiodarone is possible. But it is desirable to start this combination therapy in a hospital setting.

And almost the last pictures. I always start with the fact that if you have a patient with any supraventricular tachycardia and if there are violations of hemodynamic parameters with this supraventricular tachycardia, you do not need to remember any antiarrhythmic drugs – you need to conduct electrical cardioversion. The discharge power, I repeat, is small. The only thing is that if you’re using an older model non-synchronized defibrillator, here in atrial fibrillation the power of the first discharge is – note – 200 joules.

And the last picture. As for surgery. Here, however, there is also a typical atrial flutter and supraventricular tachycardia in the title, and we will pay attention to the yellow and green bars first of all. I was not going to talk about atrial flutter today, so we will evaluate those tachycardias that we have just talked about. Pretty good performance, to say the least. This is radiofrequency ablation. You see – 90-94%. Mortality is very low, and repeated radiofrequency ablations in yellow and green bars are 8% and 5%.

The most important thing is with AV nodal reciprocal tachycardia, when our surgeons go for an atrioventricular connection – after all, the length of the node is 6 millimeters, the width is only 3 millimeters – it is very difficult to act on fast and slow conducting channels, so the most important thing is that surgeons do not damage the atrioventricular node . Abroad, if we damage the atrioventricular connection, we get the so-called artificial complete AV block, and then we have to implant a pacemaker – this is considered a complication of this operation.