Catheter ablation of an unusual decremental accessory pathway in the left coronary cusp of the aortic valve mimicking outflow tract ventricular tachycardia

Simultaneous narrow and wide QRS complex tachycardia: Misdiagnosis or Missed diagnosis?

Tachycardia-induced tachycardia, or so-called double tachycardia, appears to be a relatively rare condition. Regardless of the mechanism, this case illustrates the importance of assessing the response to multiple different pacing maneuvers in determining the mechanism of narrow and wide QRS complex tachycardias, rather than relying upon a single maneuver, even one that is believed to be diagnostic. This article is protected by copyright. All rights reserved.

Wide complex tachycardia in a patient with non-ischemic cardiomyopathy: What is the diagnosis?

A 55-year-old male presented with acute heart failure and incessant wide complex tachycardia resembling an outflow tract ventricular tachycardia. Meticulous analysis of the electrocardiograms established the diagnosis of pre-excitation with prolonged atrio-ventricular (A-V) conduction over a decremental accessory pathway. 'Linking' between accessory pathway and normal A-V conduction system resulted in sustained maximal pre-excitation as well as periodic transition to normal A-V conduction without appreciable change in heart rate. Successful radiofrequency ablation of this atypical accessory pathway was performed at the aortic-mitral junction. This ameliorated the mechanical dysynchrony, allowed discontinuation of hemodynamic/inotropic support, and resulted in sustained symptomatic improvement. This article is protected by copyright. All rights reserved.

Successful ablation of a left anterior accessory pathway from the left coronary sinus of Valsalva near the aortic-mitral continuity

Catheter ablation of accessory pathways can be challenging depending on the location of these pathways, and accessory pathways are rare through the aortic cusps. We report a patient who underwent radiofrequency catheter ablation for manifestation of a left anterior accessory pathway from the left coronary sinus of Valsalva near the aortic–mitral continuity. Anterior accessory pathways can be safely and effectively ablated from the aortic cusps with favorable long-term outcomes.

Catheter ablation of an antidromic atrioventricular reentrant tachycardia using a slow, decrementally conducting accessory pathway in the great cardiac vein

The inability to ablate left accessory pathways (APs) from endocardial approaches may suggest an epicardial location. We report on a 43-year-old woman presenting with a wide QRS tachycardia with Right Bundle Branch Block (RBBB) morphology, right inferior axis, and the "pattern break" appearance in V2 resembled the outflow tract ventricular tachycardia. An electrophysiology study confirmed an antidromic atrioventricular reentrant tachycardia using an antegrade slow, decrementally conducting AP that was successfully ablated in the great cardiac vein-anterior interventricular vein junction after failure of endocardial approach.

Catheter ablation of anteroseptal accessory pathways from the aortic cusps: A case series and a review of the literature

Data regarding catheter ablation of anteroseptal accessory pathways through the aortic cusps are limited. We describe two cases of true para-Hisian accessory pathways successfully ablated from the aortic cusps (right coronary cusp and non-coronary cusp, respectively) along with a review of the current literature. Due to the close proximity to the atrioventricular node and the high risk of complication, mapping of the aortic cusps should always be considered in the case of anteroseptal accessory pathways. Anteroseptal accessory pathways can be safely and effectively ablated from the aortic cusps with good long-term outcomes.