Paroxysmal supraventricular tachycardia in children

Paroxysmal supraventricular tachycardia is a common arrhythmia of all ages, especially infants and young children. The disease presents with an abnormally fast heart rate, which, if left untreated, can cause dangerous complications.

Paroxysmal supraventricular tachycardia (PSVT) is one of the more common heart rhythm abnormalities, characterized by episodes of a very fast-than-normal heart rate. The cause originates in the atrium and is in the atrioventricular conduit.
Normally, the first signal to generate an impulse is at the sinus node, then the impulse travels through the entire atria, causing the atria to contract. Then, it will pass through the atrioventricular node to the ventricles, through the bohis and the purkinje network to pass through the ventricles and cause the ventricles to contract. The transmitted impulses of the impulse will correspond to the contraction of the heart muscle, normally this pacing mechanism is from 60 to 90 times/minute, corresponding to a normal heart rate. When abnormalities occur due to abnormality of these impulses or abnormalities of transmission, it will cause abnormal myocardial contractility.
Paroxysmal supraventricular tachycardia is one of the typical examples of arrhythmias in children. This condition can occur at any age, including people without heart disease. During paroxysmal supraventricular tachycardia, an abnormal conduction pathway other than the atrioventricular one occurs. This transmission causes the heart rate to increase, causing tachycardia.

Supraventricular tachycardia is divided into 3 common types including:
Tachycardia due to atrioventricular node re-entry: This is the most common form in adults, for children this form is the second most common. This situation occurs when there is an abnormal impulse source in the functional dual line or within the AV node. The impulses will pass through the abnormality and return to causing supraventricular tachycardia. Atrial tachycardia: There are some extra abnormal electrical impulses on the atria. These impulses are strong enough that an impulse can be generated across the AV node. These impulses then cause beats that are faster than normal. W.P.W syndrome (wolff parkinson white): This is a condition mainly seen in infants and young children, the tachycardia originates from the accessory pathway. That is, in addition to the main transmission through the atrioventricular node, in the W.P.W syndrome, there is another accessory pathway, which transmits the impulses faster than through the AV node. Thus, paroxysmal supraventricular tachycardia in young children is most commonly caused by WPW syndrome. Most of these syndromes are caused by spontaneous causes and some cases are caused by secondary causes such as hypertrophic cardiomyopathy, some other cardiomyopathies...

Supraventricular tachycardia episodes have episodic manifestations, so the child may have a history of prior tachycardia. The tachycardia occurs at intervals, comes on suddenly, and stops abruptly. During the attack, you will see symptoms such as fatigue, chest pain, shortness of breath, palpitations, palpable fast pulse, fussy children, restlessness, fatigue, excessive sweating, vomiting, severe convulsions and fainting. Examination: The pulse is very fast, breathing is fast, in some cases, the heart beat is large. Auscultation of the lungs may show moist rales.

In addition to clinical manifestations, to determine, it is necessary to do paraclinical tests.
Electrocardiogram (ECG): This is a test to help diagnose the disease. On the electrocardiogram, the heart rate is between 150 and 300 beats/min. P waves may or may not be visible and may be before or after the QRS complex. The QRS T complex may be normal or enlarged. Straight chest x-ray: An enlarged heart can be seen. If shock is suspected, additional tests such as blood chemistry, complete blood count, electrolytes, and urinalysis should be performed.

Paroxysmal supraventricular tachycardia is rarely life-threatening; if the tachycardia is infrequent and of short duration, no treatment is needed. In the case of frequent episodes and difficult to control without treatment, tachycardia tends to increase the number of episodes and if prolonged, there is a risk of affecting heart function.
The goals of treatment for episodes of supraventricular tachycardia in children include treatment to stop the tachycardia episode, maintenance therapy to prevent recurrences, and treatment of the underlying cause.
5.1 Treatment to cut out the heart rate Monitor electrocardiogram and handle with some measures to stimulate the X nerve as follows:
Reflex reflex: Applied to children under 1 year of age. An intravenous line should be prepared in case the heart rate drops too slowly or stops breathing. Do it by putting ice in a glove, tie it tightly, and place it on the child's face for 20 seconds. Carotid sinus massage: Apply to older children. The child lies on his back with his neck extended and turned to one side. The performer uses two fingers 2 and 3 to place in the carotid sinus and feel the carotid pulse, gently press and rub for about 15-20 seconds, close to the ECG, stop if the rhythm has slowed down. First do the right, if it fails wait 2 minutes and then do the left side again. The valsava test: Used in older children who can cooperate when asked to do it. The child takes a deep breath, then asks the child to exhale and push hard like a bowel movement, puffing out his mouth and covering his nose with one hand. Hold this position for about 10 seconds, monitor the electrocardiogram and ask the patient to breathe normally. Take action if the tachycardia is not controlled. 5.2 Preventive treatment In cases where the child has an infrequent attack, is easily controlled and is not accompanied by severe symptoms such as syncope, no treatment is required. If the child has a more frequent tachycardia, but it is not accompanied by severe symptoms, the doctor may prescribe some oral medications to prevent the occurrence of attacks such as beta-channel blockers, antiarrhythmics... If the child has a seizure, Infrequently, severe manifestations during attacks and failure of drug therapy are often treated with radiofrequency ablation. This method uses energy generated from frequency energy waves, and then burns parts of the heart tissue that are determined to be the cause of the electrical disturbances of the heart. This method is highly effective and is now widely used all over the world. In cases where the exact cause of the disease is determined, it is necessary to combine additional treatment to prevent the recurrence of supraventricular tachycardia.
Paroxysmal supraventricular tachycardia in children is not life-threatening if symptoms are mild and attacks occur infrequently. However, it increases the risk of heart failure, angina, and other cardiovascular complications. Therefore, if there are symptoms of the disease, treatment should be carried out as soon as possible.

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With a team of highly qualified and experienced specialists: Doctors with qualifications from Master's, Doctoral to Professor are reputable in medical treatment, surgery, interventional cardiac catheterization.. . is trained intensively at home & abroad. Besides, Vinmec also owns modern equipment, comparable to major hospitals in the world: the most modern operating room system in the world; The most modern silent magnetic resonance imaging machine in Southeast Asia; The CT machine has a super-fast scanning speed of only 0.275s/round without the use of heart rate-lowering drugs; The 16-sequence PET/CT and SPECT/CT systems help detect damage to cardiovascular organs early even when there are no symptoms of the disease. In addition, Vinmec also regularly cooperates with leading cardiovascular centers in Vietnam and the world such as: National Heart Institute, Cardiology Department, Hanoi Medical University, University of Pennsylvania (USA), Hospital Georges Pompidou (France) - University of Paris Descartes ... with the aim of updating modern and advanced cardiovascular treatments in the world.