case_images: PMC11833687_01
case_images: During the procedure, sustained and non-sustained episodes of atrial tachycardia were presented displaying the phenomenon of 'warm-up' and 'cool-down' during initiation and termination, respectively. P-wave was highly positive in leads II, III, aVF, and negative in lead aVL (box).
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case_images: PMC11833687_01_ytaf048f1.jpg
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case_images: P-wave was highly positive in leads II, III, aVF and negative in lead aVL (Figure 1). During the procedure, sustained and non-sustained spontaneous AT episodes (without hemodynamic compromise, blood pressure: 115/75 mmHg) with a cycle length of 485 ms and concentric pattern of activation were presented displaying the phenomenon of 'warm-up' and 'cool-down' during initiation and termination, respectively (Figures 1 and 2A).
case_images: (A) Concentric pattern of coronary sinus activation during atrial tachycardia. (B) The electroanatomical activation map demonstrated a focal origin located at the lateral aspect of the superior vena cava with radial spread of activation from the earliest activation site. (C) High-output pacing (10 V/2.0 ms) from this site resulted in phrenic nerve capture. To avoid phrenic nerve injury, the power output of radiofrequency applications was limited to 20 W.
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case_images: PMC11833687_01_ytaf048f2.jpg
case_images: ytaf048-F2
case_images: During the procedure, sustained and non-sustained spontaneous AT episodes (without hemodynamic compromise, blood pressure: 115/75 mmHg) with a cycle length of 485 ms and concentric pattern of activation were presented displaying the phenomenon of 'warm-up' and 'cool-down' during initiation and termination, respectively (Figures 1 and 2A). The electroanatomical activation map demonstrated a focal origin located at the lateral SVC aspect with radial spread of activation from the earliest activation site (Figure 2C). Ablation was performed using a 4.5-mm irrigated-tip ablation catheter (IntellaNav MiFi OI ; Boston Scientific) capable of real-time local impedance monitoring (Figure 2B).
case_images: The pentaspline pulsed-field ablation catheter was advanced into the superior vena cava to the level of the earliest activation under fluoroscopic guidance and visualization within the mapping system (A and B, respectively). (C) Two pairs of applications (with a peak voltage of 2.0 kV) were delivered inside the superior vena cava leading to the disappearance of local sharp potentials (box).
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case_images: PMC11833687_01_ytaf048f3.jpg
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case_images: The catheter was advanced into the SVC to the level of the earliest activation under fluoroscopic guidance and visualization within the mapping system (Figure 3).
case_images: (A) Post-ablation voltage mapping revealed superior vena cava isolation. (B) Activation mapping revealed the breakthrough of the sinus node during sinus rhythm. (C) The focus of the atrial tachycardia was located ~17 mm above the anatomical right atrium-superior vena cava junction where the breakthrough of the sinus node wavefront was defined.
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case_images: PMC11833687_01_ytaf048f4.jpg
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case_images: This site was located ~17 mm above the anatomical RA-SVC junction where the breakthrough of the sinus node wavefront was defined using electroanatomical mapping during sinus rhythm (Figure 4C). Post-ablation voltage mapping revealed SVC isolation (Figure 4A) while sinus node function was not compromised based on electrocardiogram monitoring (Figure 5) and activation mapping (Figure 4B).
case_images: Post-ablation 12-lead electrocardiogram revealed that sinus node function was not compromised.
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case_images: PMC11833687_01_ytaf048f5.jpg
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case_images: Post-ablation voltage mapping revealed SVC isolation (Figure 4A) while sinus node function was not compromised based on electrocardiogram monitoring (Figure 5) and activation mapping (Figure 4B).