Superior Vena Cava Isolation With Cryoballoon in AF Ablation: Randomized CAVAC AF Trial

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• The superior vena cava (SVC) is implicated as a trigger for atrial fibrillation (AF).
• Cryoballoon pulmonary vein isolation (PVI) is a common AF treatment.

Purpose of the Study:

• To compare the efficacy and safety of combining cryoballoon PVI with SVC ablation versus PVI alone for AF.
• To evaluate the impact on atrial tachyarrhythmia recurrence and complications.

Main Methods:

• A randomized trial involving 100 patients with paroxysmal or non-long-standing persistent AF.
• Patients received either PVI with SVC ablation or PVI alone.
• Daily ECG monitoring via mobile devices was used to detect atrial tachyarrhythmias.

Main Results:

• No significant difference in freedom from atrial tachyarrhythmia recurrence between 91 and 365 days post-ablation (62.9% vs. 72%, P=0.41).
• Higher rates of phrenic nerve paralysis (20.8% vs. 6%, P=0.003) and sinus node injury (18.8% vs. 0%, P=0.001) in the PVI+SVC group.
• Median atrial tachyarrhythmia burden was similar between groups (P=0.91).

Conclusions:

• Combining SVC ablation with PVI did not improve AF recurrence rates at 12 months.
• The addition of SVC ablation led to a significant increase in procedural complications.
• Routine inclusion of SVC ablation with cryoballoon PVI is not supported for first-time AF ablation.