Intra-cardiac ultrasound guided approach for catheter ablation of typical right free wall accessory pathways

Figures

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  Fig. 1. Schematic representation of the “loop” manoeuvre - the steerable long sheath (light grey curve pointing downwards) and the ablation catheter (dark grey curve pointing upwards) position in a case of anterior right free wall accessory pathway ablation. Also, division of the free wall aspect of the tricuspid annulus is shown with green dots representing each individual accessory pathway location. CS coronary sinus.

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  Fig. 2. Intra-cardiac echocardiography (ICE) image taken during mapping and ablation of the an-terior right free wall accessory pathway (AP). The 10 Fr (French scale) ICE probe was in-serted into the right atrium via the femoral vein. The ablation catheter was inserted into the right ventricle via a steerable long sheath and the described “loop” manoeuvre was used. White lines mark the presumed location of the steerable long sheath, yellow lines mark the course of the ablation catheter loop. The tip of the ablation catheter is marked with a solid white arrow, the tricuspid valve is marked with solid white arrowheads. RA right atrium, RV right ventricle, Ao aorta.

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  Fig. 3. Intra-cardiac echocardiography (ICE) image taken during mapping and ablation of the anter-olateral right free wall accessory pathway (AP). The “loop” manoeuvre was done as de-scribed in Fig. 2. White lines mark the location of the steerable long sheath that is also marked with an asterisk, yellow lines mark the presumed course of the ablation catheter loop. The tip of the ablation catheter is marked with a solid white arrow, the tricuspid valve is marked with solid white arrowheads. RA right atrium, RV right ventricle.

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  Fig. 4. Intra-cardiac echocardiography (ICE) image taken during mapping and ablation of the lateral right free wall accessory pathway (AP). The “loop” manoeuvre was done as described in Fig. 2. White lines mark the presumed location of the steerable long sheath, yellow lines mark the presumed course of the ablation catheter loop. The tip of the ablation catheter is marked with a solid white arrow, the tricuspid valve is marked with solid white arrowheads. RA right atrium, RV right ventricle.

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  Fig. 5. Intra-cardiac echocardiography (ICE) image taken during mapping and ablation of the pos-tero-lateral right free wall accessory pathway (AP). The “loop” manoeuvre was done as de-scribed in Fig. 2. White lines mark the presumed location of the steerable long sheath, yellow lines mark the presumed course of the ablation catheter loop. The tip of the ablation catheter is marked with a solid white arrow, the tricuspid valve is marked with solid white arrowheads. RA right atrium, RV right ventricle, Ao aorta.

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  Fig. 6. Endocardial electrocardiograms during mapping and ablation at the ventricular aspect of the tricuspid valve annulus. Arrow marks atrial electrocardiogram that has low amplitude and a far-field appearance, ABLD signals from distal tip of the ablation catheter, CSP-CSD signals from 10 polar diagnostic catheter inserted into the coronary sinus. Panel a shows signals during mapping of the orthodromic AVRT with an atrial electrocar-diogram that is 49 ms early compared to the reference in the CS3. Panel b shows signals during sinus rhythm after ablation at the previous site and termina-tion of the orthodromic AVRT. Panel c shows signals during mapping in sinus rhythm in a patient with clear ventricular preexcitation. The large amplitude ventricular signal is 40 ms early compared to the begin-ning of the delta wave in surface electrocardiogram tracings (I, II, V1 and aVF) and is in line with the beginning of the negative deflection in the unipolar recording from the distal tip of the ablation catheter (ABL UNI). Panel d shows signal after ablation at the previous site and termination of ventricular preexcitation.