A common heart rhythm disorder is called supraventricular tachycardia. As a rule, it is presented with repeated episodes of an increase in the frequency of beating and heaviness in the area of the organ. Although SVT is usually not life threatening, many patients suffer from recurring symptoms that have a significant impact on their quality of life. The uncertain and sporadic nature of episodes of tachycardia can cause considerable concern in many individuals.
Suddenly, a fast heartbeat characterizes SVT, and in most patients the diagnosis can be made with a high degree of reliability only by the medical history. Repeated attempts at electrocardiographic studies may prove futile.
The incidence of SVT is about 35 cases per 100,000 population per year, the prevalence is 2.25 per 1,000 inhabitants. It usually manifests itself as a recurring paroxysm of supraventricular tachycardia, the symptoms of which lead to an acute course of the disease. The main types of SVT are: Wolff-Parkinson-White syndrome, supraventricular, or supraventricular extrasystole, atrioventricular nodular tachycardia.
How does the heart work?
A vital organ consists of four chambers - two atria and two ventricles. Each heartbeat begins with tiny electrical impulses produced in the sinoatrial node. It is a pacemaker in the upper part of the right atrium. An electrical impulse travels through the heart muscle, making it work. Initially, it moves through the atria, passing into the atrioventricular node, which acts as a distributor. Then it passes through the atrioventricular bundle, acting as a conduit that supplies impulses to the ventricles. In turn, the ventricles begin to supply blood to the arteries.
What is supraventricular tachycardia, and what are the causes of its occurrence?
This disease means a fast heartbeat from the top of the ventricle, not controlled by the sinoatrial node. Another part of the heart blocks the electrical impulses in the pacemaker. The source begins above the ventricles, spreading to them. In most cases, SVT begins in early adulthood. Supraventricular tachycardia of children is also common. However, it can occur at any age. This is a rare disease, but the exact number of victims is unknown.
Supraventricular supraventricular tachycardia is caused by the following reasons:
- Medication. These include some inhalers, herbal supplements, and cold remedies.
- Drinking plenty of caffeine and alcohol.
- Stress or emotional distress.
- Smoking.
Atrioventricular and atrial type of SVT. Wolf-Parkinson-White Syndrome
AVURT is the most common type of supraventricular tachycardia. Most often observed in people over 20 years of age and in women who are over 30. Occurs when an electrical impulse occurs in the center of the heart. Often manifested in completely healthy individuals. Instead of the subsequent normal activation and impulse supply, the synotrial unit launches additional current around this short circuit. This means that the heart rate will increase rapidly, and then all the symptoms of SVT will appear.
Atrial tachycardia is a less common type. It occurs in a small area of tissue, anywhere in both atria of the heart. In most cases, the causes are unknown. However, it can occur in areas where myocardial infarction has previously been transmitted, or there are problems with the heart valve. Wolf-Parkinson-White Syndrome is developing very rapidly. Dizziness symptoms occur, loss of consciousness is possible . Sudden death is a complication of this condition, but this phenomenon is extremely rare.
Clinical manifestations
Symptoms of supraventricular tachycardia can last several seconds, minutes or even hours.
The following manifestations are possible:
- The pulse becomes 140-200 beats per minute.
- Sometimes it can be faster.
- Sensation of a pounding heart.
- Dizziness, shortness of breath.
SVT usually begins suddenly, for no apparent reason. Paroxysmal supraventricular tachycardia is manifested by pulsation in the neck or head, and may also be accompanied by chest discomfort (unusual pain), shortness of breath, anxiety. Blood pressure often decreases due to a fast heart rate, especially if it persists for several hours. In some cases, this leads to fainting or collapse.
The severity of symptoms varies greatly, depending on the function and frequency of contractions, the duration of supraventricular tachycardia, concomitant heart diseases. The individual perception of the patient is also important. Myocardial ischemia may occur.
Diagnosis of the disease
There are several ways to diagnose a disease such as supraventricular tachycardia: ECG, echocardiogram, cardiac testing with exercise. In many cases, the results of the study are usually normal.
An electrocardiograph examines the rhythm and electrical activity of an organ. This is a painless procedure and takes several minutes. If paroxysmal supraventricular tachycardia occurred during an ECG, the device can confirm the diagnosis and thereby exclude other causes of fast heartbeat.
Since it is not always possible to diagnose the presence of a disease in a hospital setting, it is recommended that the patient try to identify the disease using a portable electrocardiograph. He will record in memory all the processes that occur with the heart for 24 hours. During the procedure, you can not swim.
You may need to use an echocardiogram. It is necessary to assess cardiac structure and function, but usually the results are within normal limits. You will also need to perform some exercises necessary to determine exactly when tachycardia occurs (during exercise or in a calm state). Patients may complain of chest pain during SVT. These symptoms do not require a stress test or angiography. The decision on further testing should be based on the patient’s history and the presence of vascular risk factors.
Existing Therapy Options
Most signs of SVT stop on their own; no treatment is required. Sometimes it is possible to stop the symptoms through various measures, including drinking cold water, holding your breath or lowering your face in cold water. However, if SVT lasts for a long time with severe signs, you must immediately go to the hospital.
There are several ways to manage tachycardia:
- Short term.
- Long term.
- Pharmacological.
Below, each of them is considered separately.
Short term disease management
The purpose of this treatment is to stop acute attacks. This can be achieved through maneuvers that increase tone. For example, you can apply a cold irritant to the skin of the face. Also, with a disease such as the supraventricular form of paroxysmal tachycardia, carotid sinus massage can be done.
If such actions do not help, it is recommended to take one of these medicines:
- "Adenosine." It very quickly removes symptoms by blocking electrical impulses in the heart, but the minus is that its duration is short. In rare cases, it can aggravate bronchospasm, cause atypical chest discomfort.
- Verapamil, Diltiazem. Drugs are administered intravenously for 2-3 minutes. They carry a risk of potentiation of hypotension and bradycardia.
Long-term management of the disease
How is paroxysmal supraventricular tachycardia eliminated? Treatment is individualized depending on the frequency, severity of the episodes and the effect of symptoms on the quality of life.
Drugs are prescribed for patients in whom:
- Periodic symptomatic episodes of SVT affecting the quality of life.
- Symptoms were detected by ECG.
- Rare episodes of SVT, but the professional activity of the patient can lead to the development of the disease.
Radiofrequency catheter ablation is recommended for most of these patients. It has a small risk of complications and is therapeutic in most cases. The procedure, as a rule, takes 1.5 hours, can be performed under local anesthesia with sedation or under general anesthesia. Patients usually remain in the hospital overnight for cardiac monitoring and follow-up.
Pharmacological disease management
The goal of pharmacotherapy is to reduce the incidence of SVT episodes. Only a small proportion of patients can get rid of the symptoms of a disease such as supraventricular tachycardia. Treatment includes the following recommended drugs:
- atrioventricular nodal blocking drugs;
- antiarrhythmic drugs of I and III class.
Beta-blockers and calcium channel blockers (class II and IV) are not suitable for first-line treatment for Wolf-Parkinson-White syndrome. Randomized trials did not show the clinical superiority of any one agent. But beta-blockers and calcium channel blockers are superior to Digoxin therapy, as they provide the best blocking effect in AVURT in a state of high tone of the sympathetic nervous system. They should not be used in patients with VPU syndrome, as this can contribute to rapid conduction along additional conduction pathways during atrial fibrillation, which can lead to ventricular fibrillation.
Treatment of patients with Wolf-Parkinson-White syndrome
For patients with VPU syndrome, there is an alternative to the above medicines. To treat such a disease, it is recommended:
- "Flecainide."
- "Sotalol" (II and III class of action).
They are more effective than beta-blockers and calcium channel blockers in terms of preventing SVT, but are associated with a small risk of developing ventricular tachycardia. This risk is low in patients without structural heart disease, but complications are observed in 1-3% of patients taking Sotalol, especially those who use high doses.
Amiodarone has no role in the long-term prophylaxis of SVT in both Wolf-Parkinson-White syndrome and other types due to the high frequency of serious toxic effects on the body with prolonged use.
SVT episode prevention
You can take medications daily to prevent episodes of SVT. Various drugs can affect the electrical impulses in the heart. If some remedy does not help or causes side effects, consult a doctor for help. He will advise which medicine is needed exactly in your case.
You must inform the appropriate authorities and stop driving if you are likely to have signs of illness while driving. You can not take drugs for the prevention of SVT, this can aggravate the situation and cause other heart problems. The best prophylaxis is daily exercise of the cardiovascular system.