Once Isolated, Always Isolated?

Abstract

The regular TS was exchanged over a guidewire for a 12F steerable TS (Flexcath Advance, Medtronic Inc., Minneapolis, MN). The © 2015 American Heart Association, Inc. Original ArticleBackground-The second-generation cryoballoon delivers effective pulmonary vein isolation (PVI) associated with superior 1-year clinical outcome. However, data on reconduction of previously isolated PV are sparse. Methods and Results-A total of 421 patients underwent second-generation 28-mm cryoballoon-based PVI in 2 centers (St.George's hospital and Harburg hospital, Hamburg, Germany) between June 2012 and May 2015. Sixty-six of 421 (16%) patients (39/66, 59% women; mean age, 63±10 years, mean left atrium diameter, 45±6 mm) with a history of paroxysmal (40/66, 61%) or persistent atrial fibrillation and atrial tachyarrhythmia recurrences despite previous successful secondgeneration 28-mm cryoballoon-based PVI were included in this analysis. During the index PVI, the standard freeze cycle duration was 240 s. After successful PVI, a bonus freeze cycle of 240 s was applied in the first 15 of 66 (23%) patients, whereas no bonus freeze cycle was applied in the remaining patients. Repeat procedures were performed after a median of 205 (131-357) days following the index ablation. Electric reconduction was assessed for all PVs, and reablation was performed using radiofrequency energy. Persistent electric isolation was noted in 178 of 258 (69%) PVs. In 17 of 66 (26%) patients, all previously targeted PVs remained isolated. A significant difference toward highest reconduction rate for the posteroinferior segment of the right inferior PV was found (P=0.0002). Conclusions-The second-generation cryoballoon ablation is associated with a high rate of persistent PVI. The posteroinferior segment of the right inferior PV showed the highest reconduction rate and seems to be a predilection site for PV reconduction.

Second-generation cryoballoon ablation for recurrent atrial fibrillation after an index cryoballoon procedure: a staged strategy with variable balloon size

“…Our overall proportion of 75% chronic PVI was a composite of 64 and 82% for first- and second-generation cryoballoon index procedures, respectively, which confirms the high durable isolation with the latter, with rates comparable to previous reports [ 7 – 10 , 13 , 32 , 34 – 36 ]. Remarkably, in our series, the right inferior PV had the highest rates of durable isolation, which contrasts previous observations [ 7 , 9 , 32 , 36 ]. Durable isolation in all PVs was observed in about a third of patients, in line with previous reports.…”

“…When mapping of the PV showed reconnection, two applications were performed. In the absence of reconnection our protocol specified a single freeze, appreciating the role of fractionated ostial potentials as a contributor to recurrences [ 9 , 32 ], and the abovementioned impact of additional substrate ablation and GP modification [ 18 , 25 ]. An additional argument was that, reconnection may have gone undetected in some cases, as there was no systematic administration of adenosine prior to the redo.…”

Bonus-freeze: benefit or risk? Two-year outcome and procedural comparison of a “bonus-freeze” and “no bonus-freeze” protocol using the second-generation cryoballoon for pulmonary vein isolation

“…While one-year clinical outcome in protocols that include a bonus-freeze-cycle range between 76.8 and 83.6 %, [ 1 , 5 , 8 ] slendered protocols without a bonus-freeze-cycle also report on 80.4 to 82 % 1-year clinical efficacy [ 2 , 4 ]. Furthermore no differences were reported for durability PVI comparing a bonus- and a no bonus-freeze protocol in repeat procedures [ 13 ]. Additionally, our recent work demonstrated this observation in a smaller patients population.…”

“…Identified reconduction gaps were closed by irrigated radiofrequency (RF) ablation using a 3.5 mm irrigated-tip catheter (Biosense Webster, Navi-Star TM , Thermo-Cool TM ). The procedural endpoint was complete electrical PVI [ 13 ]. In patients with persistent isolation of all PVs admitted in SR, fractionated ostial potentials along previously performed ablation lines were identified and ablated and/or linear lesion sets were applied.…”

“…In patients with persistent isolation of all PVs admitted in SR, fractionated ostial potentials along previously performed ablation lines were identified and ablated and/or linear lesion sets were applied. In patients admitted in AF or atrial tachycardia (AT) and persistent isolation of all PVs, ostial potentials were identified and ablated followed by ablation of complex fractionated atrial electrograms and deployment of linear lesion sets in case of conversion to an AT [ 13 ].…”