Abstract

CA-43

Junctional ectopic tachycardia following aortic balloon angioplasty

Staudt G, Eagle S
Vanderbilt University Medical Center, Nashville, TN, USA

Introduction:
Junctional ectopic tachycardia (JET) is a rare arrhythmia resulting from increased automaticity of the AV node with variable retrograde VA conduction. It most commonly manifests following congenital cardiac surgery.1 JET can be challenging as it resembles supraventricular tachyarrhythmias, but its treatment differs significantly.

Case Presentation:
This is an 8-week old male with Shone’s complex manifest by a hypoplastic mitral valve with stenosis, hypoplastic aortic valve with long segment coarctation, patent ductus arteriosus (PDA), reduced left ventricle chamber size and an atrial septal defect (ASD). On day of life 5, he underwent ASD closure, PDA ligation and arch augmentation. Follow-up echocardiogram revealed moderate mitral stenosis and a “napkin ring” narrowing in the ascending aorta.

Angiography revealed focal narrowing of the ascending aorta (Fig. 1A). During dilation of the aorta, the rhythm abruptly changed from normal sinus rhythm (NSR) at a rate of 120 to a narrow complex tachycardia at a rate of ~200 (Figs. 1B and 2). Adenosine resulted in a decreased rate of atrial p waves without change in ventricular rate. The diagnosis of JET with complete AV block was made based on this pathognomonic response to adenosine. Treatment included ice packs and methylprednisolone to reduce edema from potential trauma to conduction tissue. Within 1 hour, the patient returned to NSR.

Discussion:
Arrhythmias from the development of accessory pathways are known to coexist with congenital heart disease. However, acute onset of JET may also be caused by manipulation of the AV nodal artery during cardiac procedures.1,2 In this case, acute JET occurred during an aortic balloon angioplasty, without direct manipulation of the conduction system.

Treatment of JET includes atrial pacing, active cooling, amiodarone, and systemic corticosteroids.1-3 JET is refractory to cardioversion and most anti-arrhythmic agents and can be a rare but challenging complication following percutaneous cardiac procedures.2

References:
1. Tharakan JA, Sukulal K. Post cardiac surgery junctional ectopic tachycardia: A ‘Hit and Run’ tachyarrhythmias as yet unchecked. Ann Pediatr Cardio 2014 Jan-Apr; 7(1):25-28.
2. Johnson JN, Marquardt ML, Ackerman MJ, et al. Electrocardiographic changes and arrhythmias following percutaneous atrial septal defect and patent foramen ovale device closure. Catheter Cardiovasc Interv. 2011 Aug 1;78(2):254-261.
3. Entenmann A, Michel M. Strategies for temporary cardiac pacing in pediatric patients with postoperative junctional ectopic tachycardia. J Cardiothorac Vasc Anesth. 2016 Jan;30(1):217-221.