Double factor single shot to diminish complications in cryoballoon ablation procedures for atrial fibrillation

Cryoballoon ablation dosing: From the bench to the bedside and back

“…While major complications including atrioesophageal fistula, transient ischemic attack and stroke, pericardial effusion, and tamponade were not significantly different between the cohorts, events related to cryoenergy delivery (ie, PN palsy, atrioesophageal fistula, and PV stenosis) were significantly reduced in patients with tailored vs conventional dosing (3 patients vs 8 patients; P 5 .047). 38 Collectively, these data suggest that shortened cryoballoon application times may reduce the risk of undesired energy transfer to collateral tissue.…”

“…33 Most clinical studies comparing shortened applications to conventional dosing have reported no difference in overall safety outcomes between cohorts. 19,22,34 Low rates of adverse events after cryoballoon ablation may limit the ability to detect an effect 22,34 ; therefore, several recent studies [35][36][37][38] have specifically examined the outcomes of cryoballoon dosing on collateral injury (Table 3). Chun et al 23 prospectively evaluated the outcomes between patients treated with a single 240-second application and those ablated with 2 sequential 240-second applications per PV and found a trend toward higher PN and esophageal complications (6% vs 18%, respectively; P 5 .06).…”

“…Once again, a conventional nonstandardized cryoablation approach was identified as a significant predictor for esophageal edema (P , .001). 37 Valles et al 38 reported an overall reduction in combined major and minor complications in patients treated with a "single-shot" ablation approach with variable duration (a minimum of 90 seconds with a bonus freeze if deemed necessary on the basis of TTI and nadir temperature) vs a conventional cohort who received at least 2 applications per PV (180 seconds each). While major complications including atrioesophageal fistula, transient ischemic attack and stroke, pericardial effusion, and tamponade were not significantly different between the cohorts, events related to cryoenergy delivery (ie, PN palsy, atrioesophageal fistula, and PV stenosis) were significantly reduced in patients with tailored vs conventional dosing (3 patients vs 8 patients; P 5 .047).…”

Cryoablation for atrial fibrillation

“…All used a variable-dose strategy based on TTI but differing protocols, which limits comparisons between studies. For example, the 3 observational studies with historical comparators used a fixed-dose strategy based on TTI (Pott et al, 39 who performed 2-vs 3-minute cryoapplications based on whether TTI was early [,30 seconds] or not [.30 seconds]); a TTI-plus strategy (Aryana et al, 40 who delivered 120 seconds of cryoapplication beyond the time at isolation, leading to variable exposure within and between patients); or combinations of both (Valles et al 41 ). In addition, if TTI was late (.60 seconds), both Pott et al and Aryana et al delivered a Table 2 Suggested approach to tailored cryoballoon ablation dosing I.…”

“…On the whole, these studies demonstrate that omitting the bonus cryoapplication (either as part of a variable TTI-based dosing protocol or fixed-dose protocol using 3-, 4-, or 5-minute freezes) results in significantly shorter procedure duration and lower fluoroscopy exposure, with comparable longer-term freedom from recurrent arrhythmia. 11 , 39 , 40 , 41 , 43 , 44 …”