Key result
Computational modeling demonstrated that the difference in distance to the phrenic nerves between 23 mm and 28 mm cryoballoons was only 1.7 ± 1.2 mm, indicating balloon size does not significantly alter nerve proximity.
Why the study?
Does cryoballoon size (23 mm vs 28 mm) significantly alter the distance to the phrenic nerve during simulated pulmonary vein isolation?
Does cryoballoon size (23 mm vs 28 mm) significantly alter the distance to the phrenic nerve during simulated pulmonary vein isolation?
Computational modeling reveals that cryoballoon size does not significantly alter the distance to the phrenic nerve, but deep seating the balloon can decrease the distance by up to 65%, increasing the risk of injury.
Answers are grounded in this paper and cite their sources.
Cryoballoon size unlikely to reduce phrenic nerve injury risk; leaves open effects of deployment depth in clinical validation.
The primary goal of this computational modeling study was to better quantify the relative distance of the phrenic nerves to areas where cryoballoon ablations may be applied within the left atria. Phrenic nerve injury can be a significant complication of applied ablative therapies for treatment of drug refractory atrial fibrillation. To date, published reports suggest that such injuries may occur more frequently in cryoballoon ablations than in radiofrequency therapies. Ten human heart-lung blocs were prepared in an end-diastolic state, scanned with MRI, and analyzed using Mimics software as a means to make anatomical measurements. Next, generated computer models of ArticFront cryoballoons (23, 28 mm) were mated with reconstructed pulmonary vein ostias to determine relative distances between the phrenic nerves and projected balloon placements, simulating pulmonary vein isolation. The effects of deep seating balloons were also investigated. Interestingly, the relative anatomical differences in placement of 23 and 28 mm cryoballoons were quite small, e.g., the determined difference between mid spline distance to the phrenic nerves between the two cryoballoon sizes was only 1.7 ± 1.2 mm. Furthermore, the right phrenic nerves were commonly closer to the pulmonary veins than the left, and surprisingly tips of balloons were further from the nerves, yet balloon size choice did not significantly alter calculated distance to the nerves. Such computational modeling is considered as a useful tool for both clinicians and device designers to better understand these associated anatomies that, in turn, may lead to optimization of therapeutic treatments.
No takes yet. Share an insight, caveat, or question.
Goff et al. (2015) studied Atrial Fibrillation (n=10). 23 mm and 28 mm ArticFront cryoballoons (computational modeling) vs. 23 mm vs 28 mm cryoballoons was evaluated on Distance from the phrenic nerve to the mid measurement spline of the cryoballoon (MD 1.7 mm, p=0.965). Computational modeling demonstrated that the difference in distance to the phrenic nerves between 23 mm and 28 mm cryoballoons was only 1.7 ± 1.2 mm, indicating balloon size does not significantly alter nerve proximity.
Synapse has enriched 10 related papers. Consider them for comparative context: