Successful atrioventricular nodal reentrant tachycardia ablation via superior vena cava approach in a patient with crisscross heart after modified Fontan with an extracardiac conduit surgery

Figures

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  Figure 1. Cardiac anatomy and puncture of the PA. A: Simplified anatomic illustration of the AV concordance crisscross heart. The right-sided atrium drains into the RV, which gives rise to the Ao. The LA, located on the left side, drains into the LV. Blood from the LV passes through a VSD into the RV and is then ejected into the Ao. B and C: Computed tomography showing situs solitus and concordant crisscross heart; RV on superior and LV on inferior, TA on right superior, and MA on left inferior. A VSD is observed between the ventricles. The CS runs around the MA and drains inferior to the TA. D and E: Computed tomography coronal (D) and sagittal views (E) showing the positions of the IVC, conduit, PA, and LA. F and G: Fluoroscopy AP view (F) and LAT view (G) during puncturing of the PA to the LA using the BRK needle. Ao = aorta; AP = anteroposterior; AV = atrioventricular; CS = coronary sinus; IVC = inferior vena cava; LA = left atrium; LAT = lateral; LV = left ventricle; MA = mitral annulus; PA = pulmonary artery; RA = right atrium; RV = right ventricle; SVC = superior vena cava; TA = tricuspid annulus; VSD = ventricular septal defect.

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  Figure 2. Body surface ECG and intracardiac ECG. A: Twelve-lead ECG of sinus rhythm and tachycardia. B: Intracardiac electrogram. Successful ablation site at the earliest atrial activation during tachycardia in the first session. The earliest atrial activation site was at the 1-o’clock position of the mitral annulus during tachycardia in the second session. The HA interval during tachycardia was 97 ms (this site exhibited earlier activation than the site in the first session, where the HA interval was 129 ms). Tachycardia was unaffected by the RF energy delivery at this site. C: Intracardiac electrogram at the successful ablation site in the second session. Fragmented atrial potentials were recorded at the 6-o’clock position of the TA during tachycardia. Tachycardia was terminated by eliminating small fragmented potentials (arrows) during RF application. A = atrial electrogram; ABL = ablation catheter; CA = catheter ablation; CON = conduit; ECG = electrocardiography; HA = His-atrial; LA = left atrium; LV = left ventricle; RF = radiofrequency; SVT = supraventricular tachycardia; TA = tricuspid annulus; V = ventricular electrogram.

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  Figure 3. Fluoroscopy and the CARTO. A and B: Successful ablation sites in the first session. Ablation was performed using the IVC approach in the first session. C and D: Successful ablation site at the TA in the second session. E: Atrial activation map during the tachycardia in the second session. The earliest atrial activation occurred at the 1-o’clock position of the MA. The tachycardia was not affected by the delivery of RF energy to this site. F: Atrial activation map during ventricular pacing was obtained using CARTO mapping in the second session. The His electrograms were recorded at the 5-o’clock position of the TA and on the opposite side of the MA. The earliest atrial activation site was near the His recording site. G: Assumed circuit of AVNRT induced in the second session. The left lower extension at the 1-o’clock position of the MA was retrograded, and the right lower extension present at the 5–6-o’clock position of the TA was prograded and succeeded at the fragmented potential marked by a star. AP = anteroposterior; CS = coronary sinus; IVC = inferior vena cava; LAT = lateral; MA = mitral annulus; TA = tricuspid annulus.