Adjunctive empirical superior vena cava isolation with fourth-generation cryoballoon in paroxysmal atrial fibrillation does not improve outcomes and increases complications: the randomized CISPAF trial

Figures

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  Figure 1. Flowchart of the trial. ECG, electrocardiogram; PN, phrenic nerve; PNI, phrenic nerve injury; PVI pulmonary vein isolation; RSPV, right superior pulmonary vein; SNI, sinus node impairment; SVCI, superior vena cava isolation.

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  Figure 2. Superior vena cava (SVC) ablation in the posteroanterior view. (A) Fluoroscopic image showing a decapolar catheter in the right subclavian vein for ipsilateral phrenic nerve pacing, an Achieve Advance circular mapping catheter in the SVC, and an inflated cryoballoon positioned at the SVC ostium. (B) Schematic illustration of the close anatomical relationship between the SVC and the right phrenic nerve. RSPV, right superior pulmonary vein; SVC, superior vena cava.

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  Figure 3. Real-time SVC isolation. Example of potentials recorded at the SVC ostium during cryoapplication in sinus rhythm, showing baseline activity prior to isolation and subsequent electrical isolation of the SVC. The yellow arrow marks the last SVC signal recorded by the circular mapping catheter before isolation. Surface leads I, II, aVF, V1, and V6, as well as bipolar intracardiac electrograms from the Achieve Advance circular mapping catheter (A1–2 to A7–8), are displayed. A decapolar catheter positioned in the subclavian vein was used for ipsilateral phrenic nerve pacing, with pacing spikes visible (white arrows).

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  Figure 4. Freedom from AF by Kaplan–Meier analysis in the PVI-only and PVI + SVCI groups. PVI, pulmonary vein isolation; SVCI, superior vena cava isolation.

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  Figure 5. Redo procedure with the CARTO system in a patient in whom SVC cryoablation was interrupted after 120 s due to impending phrenic nerve injury, without real-time isolation. (A) Pre-ablation map of the left atrium showing reconnection of the right inferior pulmonary vein. (B) Post-ablation map of the left atrium showing all pulmonary veins isolated. (C) Pre-ablation map showing non-isolated SVC. (D) Post-ablation map showing isolated SVC. (E) Pre-ablation SVC potentials recorded with the Octaray mapping catheter. (F) Post-ablation dissociated SVC potentials recorded with the ablation catheter. SVC, superior vena cava.