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Cryoablation System

Clinical evidence

Numerous studies have demonstrated the safety and efficacy of the POLARx™ Cryoablation System in the treatment of paroxysmal atrial fibrillation. It has been studied and is in use in multiple countries across the globe.


FROzEN-AF US IDE Clinical Trial

In a global, prospective, single-arm study, researchers evaluated the safety and effectiveness of the POLARx™ Cryoablation System for treatment of symptomatic, drug refractory, recurrent, paroxysmal atrial fibrillation (PAF). At 12 months, data revealed a 96.0% freedom from primary safety events (100% for the POLARx™ FIT 12-month extension arm study) and a 79.9% freedom from atrial arrhythmias (82% in the FIT extension study). The findings also point to an increase in Grade 4 occlusions and in successful single-shot therapy with POLARx FIT at 31 mm cryoballoon expansion.1
Clinical evidence chart
Mean ± SD
*Only ablations with duration >60S included in ablation counts
Twelve-month data on POLARx™ FIT showed low arrhythmia recurrence and freedom from primary safety events, with a high rate of Grade 3 or 4 occlusions achieved.1

Freedom from atrial arrhythmias

at follow-up (12 months) after using POLARx FIT

Major adverse events

including esophageal fistulas, persistent phrenic nerve palsy and PV stenosis

High-grade occlusion rate

resulting in either Grade 3 or Grade 4 occlusion level

Frozen AF clinical trial

download the clinical compendium


POLAR ICE multicenter study

In a prospective, nonrandomized study conducted from 2020–2023 in multiple experienced European centers, researchers using the POLARx™ Cryoablation System for pulmonary vein isolation found the device to be effective, safe and efficient.2,3
POLAR ICE study - safety chart
Procedural characteristics3
POLAR ICE study - Procedural characteristics chart
12-month efficacy2
POLAR ICE study - Efficacy chart
Performance and biophysical characteristics3
POLAR ICE study - Performance and biophysical characteristics chart
POLAR ICE multicenter study


ANTARCTICA observational study

In a multicenter prospective assessment of the POLARx™ system's efficacy and safety for PVI in an early-adopter setting of acute efficacy and safety, researchers found that use of POLARx™ resulted in a high rate of real-time pulmonary vein isolation (PVI) visualization and durable lesion creation. Following a short 25-patient learning curve, experienced operators also incurred significantly fewer adverse safety events.4

Acute PV isolation

Real-time PVI visualization

Freedom from recurrence

at 226 ± 115 days

ANTARTICA observational study


Performance vs. existing cyroablation systems

Prospective ICE AGE 1 Study

In a 1-year follow-up study comparing 103 consecutive patients with paroxysmal or persistent AF who underwent PVI with POLARx™ and 102 consecutive patients previously treated with Arctic Front Advance Pro™, POLARx demonstrated comparable safety and efficacy with lower cryoballoon nadir temperatures and improved rates of real-time visualization of PVI.5

Polarx vs. Arctic Front - Prospective ICE AGE 1 Study
Heeger et al comparison study

U.K. Comparative Study

A large United Kingdom multicenter study of 1,688 AF patients compared the POLARx™ Cryoablation System to Arctic Front Advance™ (AFA) and found comparable safety and efficacy between the systems. The POLARx cohort of 844 patients experienced a low rate of procedural complications (0.8%) with no reported phrenic nerve palsy.6

Reported phrenic nerve palsy6

Complication rate6

Procedure time6

Review data from the study United Kingdom POLARx versus AFA experience

Propensity Score-Matched Comparison

In a propensity score-matched comparison (covarying in age, gender, CHA2DS2VASc and left atrial dilation) between POLARx™ and Arctic Front Advance Pro™, POLARx™ demonstrated significantly lower procedure time and greater visualization of time-to-isolation.7

Faster procedure time

vs. Arctic Front Advance
(61 min. vs. 73 min.)

Faster to -40˚C

vs. Arctic Front Advance
(30 sec. vs. 48 sec.)

Greater real-time isolation rate

vs. Arctic Front Advance
(84% vs. 70%)

Procedural characteristics

Polarx vs. Arctic Front - Procedural characteristics
Mojica comparison study

Studies comparing POLARx™ and other cryoablation systems

Doctor looking at a laptop screen



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1. Ellenbogen KA, Mittal S, Varma N, et al. One-year outcomes of pulmonary vein isolation with a novel cryoballoon: Primary results of the FROZEN AF trial. J Cardiovasc Electrophysiol. 2024 March 6.
2. Luik A, Anic A, Asmundis C, et al. Long-term success rates of a stable, low pressure cryoballoon for the treatment of paroxysmal atrial fibrillation: Results of the prospective, international, multicenter POLAR-ICE Study. Presented at: 2023 ESC Congress, Aug. 25-28, 2023; Amsterdam, Netherlands.
3. Martin CA, Tilz RRR, Anic A, et al. Acute procedural efficacy and safety of a novel cryoballoon for the treatment of paroxysmal atrial fibrillation: Results from the POLAR ICE study. J Cardiovasc Electrophysiol. 2023 Apr;34(4):833-840. doi: 10.1111/jce.15861. Epub 2023 Feb 23. PMID: 36786515.
4. Heeger CH, Pott A, Sohns C, et al. Novel cryoballoon ablation system for pulmonary vein isolation: multicenter assessment of efficacy and safety-ANTARCTICA study. Europace. 2022 Dec 9;24(12):1917-25
5. Heeger C-H, Popescu SS, Inderhees T. et al. Novel or established cryoballoon ablation system for pulmonary vein isolation: the prospective ICE-AGE-1 study. Europace. 2023 Aug 2;25(9):euad248. doi: 10.1093/europace/euad248.
6. Honarbakhsh S, Martin CA, Mesquita J, et al. AF cryoablation is an effective day case treatment: The United Kingdom PolarX versus AFA experience. EP Europace. Sept 21, 2023. euad286.
7. Mojica J, Lipartiti F, Al Housari M, et al. Procedural safety and efficacy for pulmonary vein isolation with the novel POLARx™ Cryoablation System: A propensity score matched comparison with the Arctic Front™ Cryoballoon in the setting of paroxysmal atrial fibrillation. J Atr Fibrillation. 2021 Jun 30;14(1):20200455.

† Updated analysis with corrected data.