The 'single big cryoballoon' technique for acute pulmonary vein isolation in patients with paroxysmal atrial fibrillation: a prospective observational single centre study

Abstract

Aims: Cryothermal energy (CTE) ablation via a balloon catheter (Arctic Front, Cryocath) represents a novel technology for pulmonary vein isolation (PVI). However, balloon-based PVI approaches are associated with phrenic nerve palsy (PNP). We investigated whether 'single big cryoballoon'-deployed CTE lesions can (i) achieve acute electrical PVI without left atrium (LA) imaging and (ii) avoid PNP in patients with paroxysmal atrial fibrillation (PAF).

Methods and results: After double transseptal punctures, one Lasso catheter and a big 28 mm cryoballoon catheter using a steerable sheath were inserted into the LA. PV angiography and ostial Lasso recordings from all PVs were obtained. Selective PV angiography was used to evaluate balloon to LA-PV junction contact. CTE ablation lasted 300 s, and the PN was paced during freezing at right-sided PVs. Twenty-seven patients (19 males, mean age: 56 +/- 9 years, LA size: 42 +/- 5 mm) with PAF (mean duration: 6.6 +/- 5.7 years) were included. PVI was achieved in 97/99 PVs (98%). Median (Q(1); Q(3)) procedural, balloon, and fluoroscopy times were 220 min (190; 245), 130 min (90; 170), and 50 min (42; 69), respectively. Three transient PNP occurred after distal PV ablations. No PV stenosis occurred. Total median (Q(1); Q(3)) follow-up time was 271 days (147; 356), and 19 of 27 patients (70%) remained in sinus rhythm (3-month blanking period).

Conclusion: Using the single big cryoballoon technique, almost all PVs (98%) could be electrically isolated without LA imaging and may reduce the incidence of PNP as long as distal ablation inside the septal PVs is avoided.

Figure 1

The crosstalk technique: (A) big balloon ablation after occlusion of the left superior pulmonary vein (PV); the Lasso catheter is placed in the left inferior PV. (B) Left inferior PV ablation after exchanging balloon and Lasso positions. (C) Left superior PV Lasso recordings demonstrate remaining LA–PV conduction (arrow: PV spike, dotted line: earliest activation LSPV 15/16 indicating inferior conduction gap) and subsequent elimination of PV spike. A, atrium; CS, coronary sinus catheter; V, ventricle; LA, left atrium; LAO, left anterior oblique; PV, pulmonary vein. *Far field atrium.

Figure 2

(A–D) The hockey stick technique: the guide wire is placed in an early branching inferior pulmonary vein (PV). The balloon is advanced over the wire, thereby resulting in a hockey stick configuration of the system. This technique enables right inferior PV (2A+B) and left inferior PV (2C+D) isolation. Both schematic drawings (B and D) illustrate the basic principle of the hockey stick technique. CS, coronary sinus catheter; LAO, left anterior oblique; LIPV, left inferior pulmonary vein; LSPV, left superior pulmonary vein; RAO, right anterior oblique; RIPV, right inferior pulmonary vein; RSPV, right superior pulmonary vein; SVC, superior caval vein.

Figure 3

Pull-down technique: the balloon is positioned parallel to the pulmonary vein (PV) ostium. (A) Although angiography indicates perfect contact of the balloon only at the superior circumference of the target PV (arrows) but not at the lower PV circumference, the freeze is started regardless of the remaining leakage at the inferior PV circumference. (B) Both the sheath and the frozen cryoballoon attached to the superior PV circumference are pulled down to close the inferior gap (arrows). (C) The schematic drawings illustrate the sequential steps of the pull-down technique. CS, coronary sinus catheter; LIPV, left inferior pulmonary vein; LSPV, left superior pulmonary vein; RAO, right anterior oblique; reference catheter, CARTO backup (Biosense Webster); RIPV, right inferior pulmonary vein; RSPV, right superior pulmonary vein.

Figure 4

The big loop technique: (A) right inferior pulmonary vein (RIPV) with a large inferior gap (arrows) lacking an early PV branch. (B) The sheath is directed towards the lateral posterior left atrium, allowing the guide wire to be advanced until the distal part of the RIPV is reached. The balloon is placed over the wire at the RIPV ostium. (C) Schematic drawing of the big loop technique. CS, coronary sinus catheter; LA, left atrium; LIPV, left inferior pulmonary vein; LSPV, left superior pulmonary vein; RAO, right anterior oblique; RIPV, right inferior pulmonary vein; RSPV, right superior pulmonary vein; *Dislodged multipolar catheter. **Repositioned multipolar catheter for phrenic nerve stimulation.

Figure 5

Phrenic nerve lesion: (A) baseline angiography of right superior pulmonary vein (RSPV) in right anterior oblique. (B) Ostial balloon position at the start of the freeze. (C) Unanticipated cryoballoon ablation inside the RSPV. CS, coronary sinus catheter; PN stim, phrenic nerve stimulation; RAO, right anterior oblique; RSPV, right superior pulmonary vein; RIPV, right inferior pulmonary vein.