Approach Considerations
Acute atrial ectopic tachycardia (AET) may be a medical emergency, requiring immediate rate control. More frequently, patients are evaluated in the clinical setting, and hospitalization is often only necessary for initiation of certain antiarrhythmic medications. Although surgical cryoablation has previously been used to treat patients with atrial ectopic tachycardia, this has been primarily supplanted by catheter radiofrequency (RF) ablation techniques.
Patients with atrial ectopic tachycardia (AET) should be monitored by a cardiologist.
Historically, patients have been advised to avoid caffeine and chocolate. The role of these dietary elements must be assessed in the individual patient; most cases are not related to these dietary elements.
Go to Atrial Tachycardia and Multifocal Atrial Tachycardia for information on these topics.
Treatment of Acute AET
For patients who present in cardiac arrest or with hemodynamic compromise, establish the circulation, airway, and breathing (CABs), as is standard; provide appropriate monitoring; make sure that a defibrillator is available; and attempt conversion with a defibrillator if necessary.
Patients with atrial ectopic tachycardia (AET) may present with circulatory collapse similar to patients with cardiomyopathy. Although these patients may benefit from afterload reduction and inotropy, primary therapy aimed at reversing their tachycardia is usually more successful.
Immediate rate control is desired in the child who requires significant support, including intubation, in the intensive care unit (ICU). This can often be achieved without resorting to negatively inotropic antiarrhythmic agents. Digitalization and the use of intravenous (IV) amiodarone may quickly achieve rate control. An additional maneuver involves the use of atrial pacing (eg, esophageal, transthoracic, transvenous) to overdrive the atrial tachycardia to a point of consistent 2:1 atrioventricular (AV) block, thus lowering the ventricular response rate. [4] In the era of radiofrequency (RF) ablation, most patients who require this degree of support undergo an attempt at ablation of the focus, particularly if it is an incessant tachycardia. The use of inotropic agents such as epinephrine may increase the tachycardia rate and cause clinical deterioration.
Treatment of Chronic AET
Three options are available for treatment of patients with atrial ectopic tachycardia (AET), including medication to suppress the arrhythmia or control the ventricular response, surgery, or radiofrequency (RF) ablation.
Long-term oral medication is the mainstay of therapy in patients not undergoing RF ablation. Class IC and III antiarrhythmic agents are generally the most effective, and a staged approach is recommended. Medical therapy may be effective in as many as 75% of patients, but more than one medication is usually needed.
Radiofrequency (RF) ablation can be curative for atrial ectopic tachycardia and can be performed with a high degree of success, a low complication rate, and a low recurrence rate. [10] Success rates range from 75-100%. The complication rates are similar to other RF ablation procedures, with a higher risk of recurrence. The encircling technique uses two catheters capable of delivering RF energy as mapping catheters, alternating the reference and roving catheters, until no site provides an earlier signal than the reference. This early reference catheter is then used to deliver ablation. Atrial angiography may occasionally be helpful as a roadmap during RF catheter ablation.
Noncontact mapping systems have gained an increasing role in the ablation of atrial ectopic tachycardia. [11, 12] The ability to localize the focus, including a nonsustained focus, with accuracy is an advantage of this technique. A limitation in the pediatric population is the size of the equipment and duration of the procedures. Cummings et al reported better results using a 3-dimensional mapping system than with conventional mapping in a series of 16 patients who underwent ablation. [13]
