Robotic magnetic-guided retrograde aortic ablation of atrioventricular nodal reentrant tachycardia in transposition of the great arteries after atrial switch

Figures

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  Figure 1. Diagnostic pacing maneuvers. Shown are recordings from surface electrocardiogram leads I, II, aVF, and V1; distal (MAP1-2) and proximal (MAP3-4) ablation catheter on the septal side of the systemic venous atrium; proximal (LAA9-10) to distal (LAA1-2) left atrial appendage; and apex of the subpulmonary left ventricle (LVA). A stimulation (STIM) channel is also displayed. A: Ventricular entrainment during tachycardia. Despite wobble in the tachycardia cycle length, ventricular pacing at 470 ms accelerates atrial activation to the pacing rate. The septal VA interval in tachycardia of 75 ms, V-A-V response upon pace termination, postpacing interval minus tachycardia cycle length of 125 ms, and the delta VA interval during pacing and tachycardia of 120 ms are all consistent with a diagnosis of typical atrioventricular nodal reentrant tachycardia (AVNRT). B: A premature atrial complex (PAC) timed to His refractoriness reproducibly terminated tachycardia, thereby demonstrating obligatory involvement of the AV nodal slow pathway (SP) in the tachycardia circuit. The ladder diagram insert depicts the response to the His-refractory PAC during AVNRT. Black lines show conduction through the…

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  Figure 2. A: Imported computed tomography imaging and electroanatomic mapping. A semi-automatically segmented computed tomography image imported into the 3D electroanatomic mapping system is shown in an anteroposterior view. The dotted line illustrates the trajectory of the robotic magnetic-guided ablation catheter coursing retrograde up the aorta, traversing the aortic valve to enter the systemic right ventricle, and then looping posteriorly to cross the tricuspid valve and arrive on the septal portion of the pulmonary venous atrium. B: Biatrial activation map in tachycardia. The site of earliest atrial activation (red) adjacent to the near-field His signal (yellow sphere) in the pulmonary venous atrium is compatible with retrograde fast pathway activation. The green spheres in the lower third of Koch’s triangle indicate the site where the slow pathway was successfully ablated.

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  Figure 3. Koch’s triangle in complete transposition of the great arteries (D-TGA) with Mustard baffle. Three surgical variants for Mustard procedures are portrayed. A: The coronary sinus is excluded from a baffle that is sutured posterior to its ostium (CSO), such that Koch’s triangle is entirely in the pulmonary venous atrium. B: The coronary sinus is surgically incised to redirect coronary venous flow into the Mustard baffle, with Koch’s triangle in the pulmonary venous atrium. C: The anterior portion of the Mustard baffle is sutured anterior to the CSO to include coronary venous egress, such that the inferoposterior section of Koch’s triangle is within the systemic venous atrium. Reproduced with permission from Khairy P and Van Hare GF, Heart Rhythm 2009;6(2):283-9.1