Introduction
Atrial ectopic tachycardia is a rare condition causing arrhythmia but is a common form of incessant supraventricular tachycardia in children. Atrial ectopic tachycardia is secondary to increased automaticity of non-sinus atrial foci. In addition, atrial ectopic tachycardia has a high association with tachycardia-induced cardiomyopathy.
What Is the Cause of Atrial Ectopic Tachycardia?
Atrial ectopic tachycardia is most of the time idiopathic. Viral infections may trigger arrhythmia, but chaotic atrial tachycardia is more frequently found. Atrial tumors may be associated with atrial ectopic tachycardia. Reports identify autosomal dominant inheritance patterns. Atrial ectopic tachycardia is also observed in individuals with congenital heart disease.
How Common Is Atrial Ectopic Tachycardia?
Atrial ectopic tachycardia reportedly compromises 5 percent to 10 percent of supraventricular tachycardia. Although the incidence of pediatric supraventricular tachycardia widely varies. Atrial ectopic tachycardia occurs in approximately one case per 10000 children. Atrial ectopic tachycardia is commonly observed in infants and children; this accounts for 11 percent to 16 percent of tachycardias for which a mechanism is determined in children.
What Is the Prognosis of Atrial Ectopic Tachycardia?
Atrial ectopic tachycardia is usually well tolerated. Cardiac arrest and syncope are rarely seen except when a complication occurs. Atrial ectopic tachycardia is commonly followed by tachycardia-induced cardiomyopathy, which is often insidious. The clinical presentation depends on the duration and rate of the tachycardia, and ventricular dilatation may be present in the initial presentation, reversible with successful treatment of the arrhythmia. Several studies have shown spontaneous recurrence of ectopic atrial tachycardia in children and young adults. It is common in individuals who are withdrawing medications.
What Are the Signs and Symptoms of Atrial Ectopic Tachycardia?
History:
Atrial ectopic tachycardia is occasionally seen in individuals following surgery for congenital heart disease. Most of them have structurally normal hearts and are symptomatic. The common symptoms include chest, palpitations, lightheadedness, presyncope, and dyspnea. Asymptomatic or preverbal individuals may be noted to be dyspneic or tachycardic on routine examination. Difficulty feeding or diaphoresis may accompany the infants having tachycardia. Heart failure and exercise intolerance are late manifestations of secondary cardiac dysfunction. It is evident to rule out causes of persistently elevated heart rates, such as hyperthyroidism, anemia, or catecholamine-producing malignancy. Occasionally there may be a family history of ectopic atrial tachycardia.
Physical Examination:
The heart rate is elevated for the degree of activity. The heart rate may be regular if there is a second-degree atrioventricular block. The individual may be tachypneic. In advanced cardiomyopathy, perfusion and pulses are poor, with evidence of cardiac enlargement.
What Are the Diagnostic Considerations?
A right-sided atrial ectopic tachycardia focuses on tachycardia-induced cardiomyopathy and should be differentiated from idiopathic dilated cardiomyopathy with secondary compensatory sinus tachycardia; the degree of dysfunction and heart rate is higher, and a second-degree atrioventricular block is more common in individuals with ectopic atrial tachycardia. Atrial ectopic tachycardia should also be differentiated from atypical atrioventricular node reentry, inappropriate sinus tachycardia, and permanent junctional reciprocating tachycardia. They usually respond to adenosine with abrupt termination.
Inappropriate sinus tachycardia is associated with exercise intolerance and a minor elevation of the sinus rate. It is common in females. Approximately half the individuals with ectopic atrial tachycardia demonstrate transient atrial slowing with adenosine, and others demonstrate transient atrioventricular block. Atypically conducting ectopic atrial tachycardia must be differentiated from ventricular tachycardia. In ectopic atrial tachycardia, conduction delay is observed from the atrium to the ventricle. Most individuals demonstrate first-degree atrioventricular block and show second-degree block. Atrial flutter is an abnormal rhythm in the differential diagnosis of ectopic atrial tachycardia.
What Is the Treatment for Atrial Ectopic Tachycardia?
Approach Considerations:
Acute atrial ectopic tachycardia is a medical emergency that requires immediate rate control. Individuals are evaluated in the clinical setting, and hospital admission is only necessary for starting certain antiarrhythmic medications. Although cryoablation was used in treating ectopic atrial tachycardia, it has been supplanted by catheter radiofrequency ablation techniques.
Treatment for Acute Atrial Ectopic Tachycardia:
Circulating, airway, and breathing are established for individuals with cardiac arrest or hemodynamic compromise. Appropriate monitoring is provided. It is made sure that the defibrillator is available. Individuals may also present with circulatory collapse, similar to individuals with cardiomyopathy. However, these individuals may benefit from inotropy and afterload reduction, which aim at reversing tachycardia. Immediate rate control is achieved in the child who requires intubation in the intensive care unit. The use of intravenous Amiodarone and digitalization may achieve rate control.
Treatment for Chronic Atrial Ectopic Tachycardia:
Three options for individuals with ectopic atrial tachycardia are medications to suppress the arrhythmia or control the ventricular response, surgery, or radiofrequency ablation. Long-term oral medication is the mainstay of therapy in individuals who have not opted for radiofrequency ablation. Radiofrequency ablation can be curative for ectopic atrial tachycardia and has a high success rate. However, radiofrequency ablation has similar complication rates to other ablation techniques, with a high risk of recurrence. The encircling technique uses two catheters capable of delivering radiofrequency energy as roving catheters, and mapping catheters provide an earlier signal. The early reference catheters are used to deliver ablation. Atrial angiography may be useful in cases of radiofrequency ablation. Noncontact mapping systems have increased the ablation of ectopic atrial tachycardia. The ability to localize the focus, including a nonsustained focus with accuracy, is an advantage of this approach. A limitation in the periodic population issue is the equipment size and duration of the procedures.
Medications Used:
Drugs including Digoxin, Amiodarone, Propafenone, Flecainide, Sotalol, Procainamide, and Esmolol.
Diet:
Individuals have been advised to avoid caffeine and chocolate. The role of these dietary elements must be assessed in the individuals.
What Are the Complications of Atrial Ectopic Tachycardia?
Atrial ectopic tachycardia is one of the incessant tachycardias associated with myocardial dysfunction if the ventricular rate remains elevated over the long term.
Conclusion
Atrial ectopic tachycardia, also called atrial tachycardia, is an abnormally fast heart rate originating from the top of the heart. Atrial ectopic tachycardia is most of the time idiopathic. Treatment involves antiarrhythmic drugs. Also, it is important to make certain dietary and lifestyle changes to prevent further complications.
