March 27, 2023Open Access
Efficacy, Safety and Feasibility of Superior Vena Cava Isolation in Patients Undergoing Atrial Fibrillation Catheter Ablation: An Up-to-Date Review
Key Result
Superior vena cava isolation on top of pulmonary vein isolation has largely failed to demonstrate clinical benefit for arrhythmia recurrence, though safety and feasibility are undisputable.
Structured PICO
Does superior vena cava isolation reduce arrhythmia recurrence in patients undergoing atrial fibrillation catheter ablation?
P
Population
Patients undergoing atrial fibrillation catheter ablation
I
Intervention
Superior vena cava isolation (SVCI) (empiric or as-needed) on top of pulmonary vein isolation (PVI)
C
Comparator
Pulmonary vein isolation (PVI) alone
O
Outcome
Arrhythmia recurrence, safety, and feasibility
Current evidence does not support routine superior vena cava isolation in addition to pulmonary vein isolation for atrial fibrillation ablation to prevent arrhythmia recurrence, though the procedure is safe and feasible.
Limitations
- Mixed population demographics
- Small number of enrollees
- Short follow-up
Abstract
Pulmonary vein isolation (PVI) is the cornerstone in atrial fibrillation (AF) ablation; yet, the role of arrhythmogenic superior vena cava (SVC) is increasingly recognized and different ablation strategies have been employed in this context. SVC can act as a trigger or perpetuator of AF, and its significance might be more pronounced in patients undergoing repeated ablation. Several cohorts have examined efficacy, safety and feasibility of SVC isolation (SVCI) among AF patients. The majority of these studies explored as-needed SVCI during index PVI, and only a minority of them included repeated ablation subjects and non-radiofrequency energy sources. Studies of heterogeneous design and intent have explored both empiric and as-needed SVCI on top of PVI and reported inconclusive results. These studies have largely failed to demonstrate any clinical benefit in terms of arrhythmia recurrence, although safety and feasibility are undisputable. Mixed population demographics, small number of enrollees and short follow-up are the main limitations. Procedural and safety data are comparable between empiric SVCI and as-needed SVCI, and some studies suggested that empiric SVCI might be associated with reduced AF recurrences in paroxysmal AF patients. Currently, no study has compared different ablation energy sources in the setting of SVCI, and no randomized study has addressed as-needed SVCI on top of PVI. Furthermore, data regarding cryoablation are still in their infancy, and regarding SVCI in patients with cardiac devices more safety and feasibility data are needed. PVI non-responders, patients undergoing repeated ablation and patients with long SVC sleeves could be potential candidates for SVCI, especially via an empiric approach. Although many technical aspects remain unsettled, the major question to answer is which clinical phenotype of AF patients might benefit from SVCI?