Cryoballoon Ablation Group Research Articles

Radiation exposure in cryoballoon ablation compared to radiofrequency ablation with three-dimensional electroanatomic mapping in atrial fibrillation patients.

Catheter ablation for atrial fibrillation (AF) has become an established treatment to control symptoms. AF ablation either by cryoballoon or radiofrequency using three-dimensional (3D) electroanatomical mapping exposes patients and medical staff to increased doses of radiation. To compare radiation exposure in patients during cryoballoon ablation compared to 3D electro-anatomic mapping catheter ablation in AF patients. Atotal of 30 patients referred for AF ablation underwent full history taking, 12-lead ECG, echocardiogram, and pulmonary vein isolation either by 3D mapping system or cryoballoon. Procedure duration and fluoroscopy time were collected and analyzed. Radiation exposure was measured using thermoluminescent dosimeters placed at different sites related to patients and medical staff. The procedural time was statistically significantly longer with 3D mapping compared to cryoballoon but showed no significant difference regarding fluoroscopy time. There was asignificantly higher radiation skin dose at the right scapular area in the cryoballoon ablation group, in addition to higher peak skin dose compared to the 3D mapping ablation group. There was no statistically significant correlation between peak skin doses and fluoroscopy duration but astatistically significant correlation between peak skin dose and usage of high frame rate and the high dose area product. Cryoballoon ablation was found to be associated with higher peak skin radiation doses especially in the right scapular area. Knowing dose area product and peak skin dose is more important than fluoroscopy time alone.

Cryoballoon vs radiofrequency ablation of atrial fibrillation: insights from the Veterans Healthcare System.

Catheter ablation is considered the mainstay treatment for drug-refractory atrial fibrillation (AF). The aims of our study were to compare the efficacy and safety of the most two currently approved approaches (point-by-point radiofrequency ablation (RFA), either with contact force (CF) or without contact force (nCF) catheters, and cryoballoon ablation (CBA)) in the Veterans Healthcare System. We performed a retrospective study of patients who underwent ablation for treatment of AF at the veterans affairs healthcare system between 2013 and 2018. Only the first reported ablation procedure was included. We included 956 patients in the study (97.4% males, 91.5% Caucasians, 67% paroxysmal AF), with 682 patients in RFA-nCF, 139 in RFA-CF, and 135 in CBA. Thirty-day complication rates were comparable between the three groups with the exception of higher incidence of phrenic nerve injury in CBA group when compared to RFA-nCF (2.2% vs 0.0%, p < 0.01). Long-term recurrence rate of AF was significantly lower in the CBA group when compared to RFA-nCF (33.3% vs 47.7%, adjusted HR 0.60, 95% CI 0.44-0.83, p < 0.01). On the other hand, it was similar between RFA-CF and RFA-nCF groups (43.9% vs 47.7%, adjusted HR 1.01, 95% CI 0.76-1.33, p 0.97). After stratifying patients based on AF type, these findings were only present in patients with paroxysmal AF. CBA for paroxysmal AF, in male dominant patients' population, was associated with lower incidence of AF recurrence rate while having a comparable safety profile to RFA independent of the use of CF catheters.

Difference of myocardial injury, inflammation and early recurrence after pulmonary vein isolation among laser balloon ablation, radiofrequency catheter ablation and cryoballoon ablation

Abstract Background Pulmonary vein isolation (PVI) has become well-established as the main therapy for patients with drug-refractory paroxysmal atrial fibrillation (PAF) and various isolation methods including radiofrequency ablation (RFA), cryoballoon ablation (CBA) and laser balloon ablation (LBA) were available. Pathological findings in each ablation methods such as myocardial injury and inflammation are thought to be different. High sensitive cardiac troponin I (hs-TnI), subunit of cardiac troponin complex, is a sensitive and specific marker of myocardium injury. High-sensitive C-reactive protein (hs-CRP) is a biomarker of inflammation and is elevated following cardiomyocyte necrosis. Relationship between myocardial injury and inflammation after ablation using RFA, CBA and LBA and early recurrence of atrial fibrillation (ERAF) remains unclear. Methods We enrolled consecutive PAF patients from Osaka Rosai Atrial Fibrillation (ORAF) registry who underwent PVI from January 2019 to October 2019. We compared the clinical characteristics including age, gender, hypertension, diabetes mellitus, history of heart failure, CHADS2Vasc score, renal function, serum BNP level and echocardiographic parameters including left ventricular dimensions, left atrial diameter (LAD) and left ventricular ejection fraction (LVEF) between RFA, CBA and LBA groups. We investigated the difference of relationship between myocardial injury marker (hs-TnI), inflammation markers (white blood cell change (DWBC) from post to pre PVI, neutrophil-to-lymphocyte ratio change (DNLR) from after to before PVI and hs-CRP) at 36–48 hours after PVI and ERAF (&amp;lt;3 months after PVI) between each group. Results We enrolled 187 consecutive PAF patients who underwent PVI. RFA, CBA and LBA groups comprised 108, 57 and 22 patients, respectively. There were no significant differences of age, gender, hypertension, diabetes mellitus, history of heart failure, CHADS2Vasc score, renal function, serum BNP level and echocardiographic parameters between each group. Serum hs-TnI in RFA group and LBA group were significantly lower than in CBA group (2.643 ng/ml vs 5.240ng/ml, 1.344 ng/ml vs 5.240 ng/ml, p&amp;lt;0.001, p=0.002, respectively, Figure). DWBC was significantly higher in LBA group than CBA group (1157.3/μl vs 418.4/μl, p=0.045). DNLR did not differ between each group. Hs-CRP in RFA group and LBA group were significantly higher than in CBA group (1.881 mg/dl vs 1.186 mg/dl, 2.173 mg/dl vs 1.186 mg/dl, p=0.010, p=0.003, respectively, Figure). Incidence of ERAF was significantly higher in LBA group than RFA group (36.4% vs 16.7%, p=0.035). Incidence of ERAF tended to be higher in LBA group than CBA group (36.4% vs 19.3%, p=0.112). Conclusion LBA may cause less myocardial injury than RFA and CBA, on the contrary LBA may cause more inflammation than CBA. Incidence of ERAF in LBA was highest between each procedure. Inflammation markers and ERAF Funding Acknowledgement Type of funding source: None

Outcome of contact force-guided radiofrequency catheter ablation or second generation cryoballoon ablation for paroxysmal atrial fibrillation: propensity score matched analysis

Abstract Background Little has been reported on the outcome of contact force (CF)-guided radiofrequency catheter ablation (RFCA) and second generation cryoballoon ablation (CBA). Purpose The purpose of this study was to compare the outcome of CF-guided RFCA and second generation CBA for paroxysmal atrial fibrillation (PAF). Methods We enrolled the consecutive 364 patients with PAF who underwent initial ablation between September 2014 and July 2018 in our hospital. We compared the late recurrence of atrial tachyarrhythmia more than three months after ablation between RFCA group and CBA group. All RFCA procedures were performed using CF-sensing catheter and all CBA procedures were performed using second generation CB. Results There were significant differences in background characteristics: chronic kidney disease, serum brain natriuretic peptide level, and left ventricular ejection fraction. After propensity score matched analysis (Table), atrial tachyarrhythmia free survival was significantly higher in CBA group than in RFCA group (Figure). Conclusions Second generation CBA showed a significantly lower late recurrence rate compared to CF-guided RFCA. Kaplan-Meier Curve Funding Acknowledgement Type of funding source: None

Lesion characteristics between cryoballoon ablation and radiofrequency ablation with a contact force-sensing catheter: Late-gadolinium enhancement magnetic resonance imaging assessment.

Pulmonary vein isolation (PVI) lesions after cryoballoon ablation (CBA) are characterized as a wider and more continuous than that after conventional radiofrequency catheter ablation (RFCA) without the contact force (CF)-sensing technology. However, the impact on the lesion characteristics of ablation with a CF-sensing catheter has not been well discussed. We sought to assess the lesions using late-gadolinium enhancement magnetic resonance imaging (LGE-MRI) and to compare the differences between the two groups (CB group vs. RF group). A total of 30 consecutive patients who underwent PVI were enrolled (CB group, 18; RF group, 12). The RF applications were delivered with a target lesion size index (LSI) of 5. The PVI lesions were assessed by LGE-MRI 3 months after the PVI. The region around the PV was divided into eight segments: roof, anterior-superior, anterior carina, anterior inferior, bottom, posterior inferior, posterior carina, and posterior superior segment. The lesion width and visual gap of each segment were compared between the two groups. The visual gaps were defined as no-enhancement site of >4 mm. The mean LSI was 4.7 ± 0.7. The lesion width was significantly wider but the visual gaps were more frequently documented at the bottom segment of right PV in the CBA group (lesion width: 8.1 ± 2.2 vs. 6.3 ± 2.2 mm; p = .032; visual gap at the bottom segment or right PV: 39% vs. 0%; p = .016). The PVI lesion was wider after CBA, while the visual gaps were fewer after RFCA with a CF-sensing catheter.

Hot balloon versus cryoballoon ablation for persistent atrial fibrillation: Lesion area, efficacy, and safety.

The clinical efficacy and safety of hot balloon ablation (HBA) for the treatment of persistent AF (PerAF) remain unclear. We aimed to evaluate the clinical efficacy and safety of HBA versus cryoballoon ablation (CBA) as a treatment for PerAF. Of 195 consecutive patients who underwent initial catheter ablation for PerAF (AF lasting for longer than7 days but shorter than 12 months), 158 propensity score-matched (79 HBA and 79 CBA) patients were included in our retrospective study. All patients who underwent HBA received applications of energy to the upper posterior LA wall with a larger balloon in addition to single shots to each pulmonary vein (PV) ostium, whereas those who underwent CBA received simple single-shot applications. The electrically isolated surface area (ISA), including the PV antrum and part of the posterior LA wall, was assessed by high-resolution mapping. The success of the PV isolation with balloon shots alone did not differ between HBA and CBA (81% vs. 85%; p = .52). The ISA was generally wide in both groups and significantly larger in the HBA group than in the CBA group (61 ± 16% vs. 51 ± 12%; p < .001). The incidence of procedure-related complications did not differ significantly (HBA 4% vs. CBA 1%; p = .62) nor did the arrhythmia recurrence rate (HBA 11% vs. CBA 18% at 18 months; p = .26). Despite the difference in protocols, HBA and CBA performed for PerAF appear comparable in terms of wide antral lesion creation, clinical efficacy, and safety. Further prospective studies, based on a unified methodology, are needed.

A prospective multicenter study of direct comparison of feasibility and safety of pulmonary vein isolation using the minimally interrupted apixaban between second-generation cryoballoon and radiofrequency ablation of paroxysmal atrial fibrillation: J-HIT apixaban.

BackgroundThe feasibility and safety of pulmonary vein isolation (PVI) using cryoballoon (CB) for paroxysmal atrial fibrillation (PAF) with minimally interrupted apixaban has not fully explored.MethodsIn this multicenter, randomized prospective study, we enrolled patients with PAF undergoing CB or radiofrequency (RF) ablation with interrupted (holding 1 dose) apixaban. The primary composite end point consisted of bleeding events, including pericardial effusion and major bleeding requiring blood transfusion, or thromboembolic events at 4 weeks after ablation; secondary end points included early recurrence of AF and procedural duration.ResultsA total of 250 patients underwent PVI (125 assigned to the RF ablation and 125 assigned to the CB ablation). The primary end point occurred in 1 patient in the CB ablation group (0.8%; 90% confidence interval [CI], 0.04 to 3.70) and 3 patients in the RF group (2.4%, P = .622; risk ratio, 0333; 90% CI, 0.05 to 2.20). All events were pericardial effusion, all of whom recovered after pericardiocentesis. Early recurrence of AF occurred in 4 patients (3.2%) in the RF group and in 6 patients (4.8%) in the CB group (P = .749). The procedural duration was shorter in the CB group than that in the RF group (136.5 ± 39.9 vs 179.5 ± 44.8 min, P < .001).ConclusionCB ablation with minimally interrupted apixaban was feasible and safe in patients with PAF undergoing PVI, which was equivalent to RF ablation.

Early recurrence of atrial fibrillation after pulmonary vein isolation: a comparative analysis between cryogenic and contact force radiofrequency ablation.

Early recurrence (ER) of atrial fibrillation (AF) within 90 days post-ablation is observed in up to 50% of patients and has been attributed to transient inflammation. The importance of ER in current era of pulmonary vein isolation (PVI) with cryoballoon ablation (CBA) and contact-force catheter radiofrequency ablation (cfRFA) has not been clearly reported. In addition, it is not known whether there are differences between types of ablation energy used during PVI. Study population was drawn from a prospective multicenter database of AF ablation. Consecutive patients undergoing first-time ablation with PVI alone, using either second-generation CBA or cfRFA catheters were included. Patients were followed at 0.5, 3, 6, and 12 months to assess recurrence. Predictors of late recurrence (LR), defined as recurrence outside the blanking period, were assessed by Cox proportional hazards regression models. Freedom from LR was calculated and compared between two groups using the Kaplan-Meier method and log-rank test. Study cohort included 300 patients (1:1 CBA:RFA, age 63.6 ± 10.3 years, 67% male). There were no baseline characteristic differences between the CBA and cfRFA groups. ER occurred in 23.3% and 16.7% of patients in the CBA and cfRFA groups, respectively (p = 0.149). One-year freedom from LR was similar for both groups (72.7% CBA vs. 78% cfRFA, p = 0.287). Fifty-two patients (25 CBA and 27 cfRFA) underwent repeat ablation and no difference in durability of PVI was found. ER was the only common independent predictor of LR for either group and for the entire cohort (HR 2.3). In our series of AF ablation using second-generation cryoballoon and contact-force RFA catheters, recurrence in the "blanking period" is seen in 20% and remains predictive of late recurrence irrespective of the energy used.

P1914Relationship between myocardial injury, inflammation and early, late recurrence after pulmonary vein isolation may be different between radiofrequency catheter ablation and cryoballoon ablation

Abstract Background High sensitive cardiac troponin I (hs-TnI), subunit of cardiac troponin complex, is a sensitive and specific marker of myocardium injury as troponin T. Several studies showed hs-TnI was associated with worse cardiovascular outcomes but relationship between serum hs-TnI level in patients with atrial fibrillation (AF) after pulmonary vein isolation (PVI) and AF recurrence remains unclear. Methods We enrolled 444 consecutive AF patients who underwent PVI from May 2017 to September 2018. We investigated the difference of relationship between serum hs-TnI, inflammation markers at 48 hours after PVI and early or late recurrence of AF (ERAF, &lt;3 months and LRAF, during 1 year after PVI in patients with AF) between radiofrequency ablation (RFA) group and cryoballoon ablation (CBA) group. Results RFA and CBA were performed in 328 and 116 patients, respectively. There were no significant differences in patient characteristics between RFA group and CBA group. Serum hs-TnI in RFA group was significantly lower than in CBA group (1.93 ng/ml±3.28 vs 5.08 ng/ml±4.29, p&lt;0.001), while hs-CRP was significantly higher in RFA group than CB group (1.97±2.38 mg/dl vs 1.10±0.84 mg/dl, p&lt;0.001). The incidence of ERAF was similar between the two groups (RFA group: 26.8% and CBA group: 21.6%, p=0.262). There was no significant difference of hs-TnI and hs-CRP between patients with ERAF and without ERAF (table). In 213 patients who were followed during 1 year (PVIs were performed from May 2017 to January 2018, RFA 149 and CBA 64 patients), there was no significant association between hs-TnI, hs-CRP and incidence of LRAF (table). TnI and CRP between RFA and CBA RFA (n=328) CBA (n=116) P value hs-TnI 1.93±3.28 5.08±4.29 &lt;0.001 hs-CRP 1.97±2.38 1.10±0.84 &lt;0.001 3 months follow-up RFA (n=328) CBA (n=116) ERAF (+) ERAF (−) P value ERAF (+) ERAF (−) P value hs-TnI 1.68±1.90 2.02±3.66 0.410 5.03±3.17 5.10±4.56 0.943 hs-CRP 2.23±2.65 1.88±2.27 0.238 1.01±0.84 1.13±0.85 0.524 1 year follow-up RFA (n=149) CBA (n=64) LRAF (+) LRAF (−) P value LRAF (+) LRAF(−) P value hs-TnI 1.61±1.77 1.87±2.69 0.570 4.71±2.14 5.60±5.69 0.664 hs-CRP 2.18±2.24 1.92±2.24 0.550 1.12±0.64 1.12±0.98 0.991 Conclusion CBA may cause more myocardial injury than RFA, on the contrary RFA may cause more inflammation than CBA. These markers did not affect ERAF and LRAF after PVI.

Earliest pulmonary vein potential-guided cryoballoon ablation for atrial fibrillation.

No studies have evaluated both the time-to-isolation (TTI) and the sequence of pulmonary vein (PV) potentials in cryoballoon ablation (CBA) for atrial fibrillation (AF). This study aimed to prospectively evaluate the acute results of pulmonary vein isolation (PVI) using a novel CBA technique-the earliest potential (EP) of PV-guided CBA-in paroxysmal AF. We pressed a balloon against the earliest PV potential site during PVI when TTI could not be achieved within 60s (EP-guided CBA group). We compared 32 patients consecutively treated by EP-guided CBA to 32 patients treated without pressing the balloon against the EP site (conventional CBA group). The cryoapplication protocol was the same, except with regard to the pressing of the balloon. All 256 PVs (EP-guided CBA group, 128 PVs; conventional CBA group, 128 PVs) were isolated successfully. The TTI observation rate was similar in both groups. Compared with conventional CBA, EP-guided CBA was associated with a lower non-success rate of TTI ≤ 90s (9% vs. 26%; P = 0.040) and shorter left atrial dwell time (38 ± 9 vs. 46 ± 19min; P = 0.036), total procedure time (76 ± 15 vs. 87 ± 23min; P = 0.043), and fluoroscopy time (23 ± 8 vs. 30 ± 11min; P = 0.006). This novel EP-guided CBA approach may help facilitate the ablation procedure.

Clinical significance of early recurrence of atrial fibrillation after cryoballoon vs. radiofrequency ablation-A propensity score matched analysis.

ObjectivesOne of the mechanisms of early recurrence of atrial fibrillation (ERAF) after AF ablation is considered to be the inflammatory reaction of the atrial tissue. The aim of this study is to compare the clinical significance of ERAF at each stage for true AF recurrence between cryoballoon (CB) and radiofrequency (RF) ablation.MethodsAmong 798 paroxysmal AF patients who underwent an initial ablation, 460 patients (CB, n = 230; RF, n = 230) were selected by propensity score matching. Very ERAF (VERAF), ERAF-1M, ERAF-3M and true AF recurrence were defined as AF recurrence at 0–2, 3–30, 31–90 days and more than 90 days after the procedure, respectively.ResultsThe patient characteristics of the two groups were similar. ERAF was observed 21% and 27% in the CB and RF groups, respectively. In both the CB and RF group, VERAF, ERAF-1M and ERAF-3M were more frequently observed in patients with true AF recurrence than in those without. In a multivariable analysis, ERAF-1M and ERAF-3M were found to be independent predictors of true AF recurrence in both the CB (P = 0.04 and P<0.001, respectively) and RF groups (P = 0.02 and P = 0.001, respectively). However, while VERAF was associated with true AF recurrence after RF ablation (P = 0.03), it was not associated with true AF recurrence after CB ablation (P = 0.19).ConclusionThe relationship between ERAF and true AF recurrence differed between the RF and CB ablation groups. While VERAF was associated with true AF recurrence after RF ablation, it was not a predictor of true AF recurrence after CB ablation.

Cryoballoon Ablation for the Treatment of Atrial Fibrillation: A Meta-analysis.

Background:Ablation therapy is the treatment of choice in antiarrhythmic drug-refractory atrial fibrillation (AF). It is performed by either cryoballoon ablation (CBA) or radiofrequency abla-tion. CBA is gaining popularity due to simplicity with similar efficacy and complication rate com-pared with RFA. In this meta-analysis, we compare the recurrence rate of AF and the complications from CBA versus RFA for the treatment of AF.Methods:We systematically searched PubMed for the articles that compared the outcome of interest. The primary outcome was to compare the recurrence rate of AF between CBA and RFA. We also in-cluded subgroup analysis with complications of pericardial effusion, phrenic nerve palsy and cerebral microemboli following ablation therapy.Results:A total of 24 studies with 3527 patients met our predefined inclusion criteria. Recurrence of AF after CBA or RFA was similar in both groups (RR: 0.84; 95% CI: 0.65, 1.07; I2=48%, Cochrane p=0.16). In subgroup analysis, heterogeneity was less in paroxysmal AF (I2=0%, Cochrane p=0.46) compared to mixed AF (I2=72%, Cochrane p=0.003). Procedure and fluoroscopy time was less by 26.37 and 5.94 minutes respectively in CBA compared to RFA. Complications, pericardial effusion, and silent cerebral microemboli, were not different between the two groups, however, phrenic nerve palsy was exclusively present only in CBA group.Conclusion:This study confirms that the effectiveness of CBA is similar to RFA in the treatment of AF with the added advantages of shorter procedure and fluoroscopy times.

Clinical success of cryoballoon pulmonary vein isolation in patients with atrial fibrillation

Aim. To estimate the clinical success of cryoballoon pulmonary vein isolation (PVI).Methods.230 patients (males: 49.6%, mean age 57 (53; 62) with symptomatic paroxysmal and persistent atrial fibrillation (AF) resistant to antiarrhythmic therapy were included in a single-center prospective study. The patients were randomized into 2 groups to undergo either cryoballoon ablation (n = 122) or radiofrequency (RF) (n = 108) ablation. Both groups were comparable in baseline parameters. The follow-up period was 12 months. Clinical outcomes were estimated with the use of a three-stage scale. The rates of cardiovascular rehospitalizations, direct-current cardioversions and repeated ablations during were estimated within the follow-up. The quality of life (QoL) in the cryoablation group was measured using the AFEQT scale.Results.77% (n = 94) of patients in the cryoballoon ablation group and 71.3% (n = 77) of patients in the RF group (р = 0.71) demonstrated reported the optimal clinical effects. Both groups, cryo ablation and RF ablation, had similar rates of cardiovascular hospitalizations (23.8 vs 28.7%, OR 0.8, 95% CI 0.4–1.4; р = 0.39), direct-current cardioversions (12.3 vs 17.6%, OR 0.7, 95% CI 0.3–1.4; р = 0.26) and repeated ablations (9.8–11.1%, OR 0.9, 95% CI 0.4–2.0; р = 0.75). The patients treated with cryoballoon as opposed to RF ablation had significantly more successful usage of “pill-in-pocket” strategy – 14.8 vs 6.5% (OR 2.5, 95% CI 1.01–6.2; р = 0.04). Significant improvements of the QoL parameters with strong size effect have been found in the cryoablation group, i.e. global score (GS) increased by 8.9±6.9 (95% CI 6.6–10.1; dCohen 1.2; р&lt;0.001), symptoms (S) – by 8.3±7.9 (95% CI 4.2–8.8; dCohen 1.5; р&lt;0.001), daily activities (DA) – by 10.0±6.9 (95% CI = 6.4–10.6; dCohen 0.9; р&lt;0.001), treatment concerns (TC) – by 5.5±6.0 (95% CI 6.3–9.2; dCohen 1.2; р&lt;0.001) and treatment satisfaction (TS) – by 5.5±6.0 (95% CI 5.4–9.8; dCohen 0.9; р&lt;0.001).Conclusion.The both catheter-based technologies had comparable clinical success. Cryoablation was characterized by improvement in all QoL parameters based on the AFEQT score.

Long Term Outcome and Pulmonary Vein Reconnection of Patients Undergoing Cryoablation and/or Radiofrequency Ablation: Results from The Cryo Versus RF Trial.

Long term prospective data comparing the efficacy of radiofrequency (RF) and cryoballoon ablation (CRYO) for paroxysmal atrial fibrillation (PAF) is lacking. We report the long-term outcomes of a randomized control trial comparing CRYO to RF ablation, or a novel COMBINED approach (RF followed by CRYO) for PAF. We studied the number and pattern of pulmonary vein (PV) reconnections in patients undergoing repeat procedure(s). The COMBINED approach had significantly higher single procedure success rate and is associated with the fewest reconnected PVs. 203 patients who underwent first time PAF ablation in a randomized clinical trial comparing CRYO (67), RF (67) and COMBINED (69) approaches were followed up. All patients with symptomatic recurrence of AF were offered a repeat procedure(s). Reconnected PV(s) at repeat procedure(s) were recorded. In a subset, the PV reconnection sites during the first repeat procedure were prospectively assessed and categorised into one of 8 segments. . At 5 years, 57% of COMBINED patients remained free of AF after a single procedure compared to 47% CRYO and 19% RF patients (p<0.001 COMBINED vs RF and CRYO vs RF, p=0.043 COMBINED vs CRYO). During the first repeat procedure, theCOMBINED group had less number of reconnected PVs (mean number of reconnected PVs in the COMBINED group 1.2 vs 2.3 CRYO and 2.4 RF, p=0.034). There was a different pattern of PV reconnection comparing the CRYO and RF groups. The COMBINED approach had a significantly higher single procedure success rate with fewer reconnected PVs and fewer reconnection sites compared to either CRYO or RF alone. CRYO in turn was superior to RF. PV reconnection pattern differed between CRYO and RF and the synergistic effect of the COMBINED approach may explain the improved single procedure efficacy.

Cryoballoon antral pulmonary vein isolation vs contact force-sensing radiofrequency catheter ablation for pulmonary vein and posterior left atrial isolation in patients with persistent atrial fibrillation

The role of cryoballoon ablation (CBA) for antral pulmonary vein isolation (APVI) has not been well established in persistent atrial fibrillation (PerAF). Isolation of the left atrial posterior wall (BOX) after APVI has been suggested to improve the efficacy of radiofrequency catheter ablation (RFA) in PerAF. The purpose of this study was to compare characteristics and clinical outcomes of APVI by CBA vs APVI + BOX by contact force-guided RFA (CF-RFA) in patients with PerAF. APVI was performed in 167 consecutive patients with PerAF (mean age 64 ± 9 years; left atrial diameter 46 ± 6 mm) using CBA (n = 90) or CF-RFA (n = 77). After APVI, a roofline was created in 33 of 90 patients (37%) in the CBA group and BOX was performed in all 77 patients in the CF-RFA group. During 21 ± 10 months of follow-up after a single ablation procedure, 37 of 90 patients (41%) in the CBA group (APVI) and 39 of 77 (51%) in the CF-RFA group (APVI + BOX) remained in sinus rhythm without antiarrhythmic drugs (AADs) (P = .22). During repeat ablation, APVI + BOX using CF-RFA was performed in 20 of 90 patients (22%) and in 18 of 77 patients (23%) who initially underwent CBA or CF-RFA, respectively. At 19 ± 10 months after repeat ablation, sinus rhythm was maintained in 55 of 90 patients (61%) and 52 of 77 patients (68%) in the CBA and CF-RFA groups without AADs, respectively (P = .39). In PerAF, an initial approach of APVI by CBA or APVI+ BOX by CF-RFA has a similar efficacy of 40%-50% without AADs. After repeat ablation for APVI + BOX by CF-RFA in ∼25%, sinus rhythm is maintained in 60%-70% of patients without AADs.

PP135 Cost-Effectiveness Of Cryoballoon Ablation In China: Real-World Results

Introduction:Paroxysmal atrial fibrillation (PAF) represents a significant economic burden to the healthcare system. Catheter ablation is a commonly adopted treatments for PAF, and cryoballoon ablation (CBA) has been recently proven to be as effective as radiofrequency ablation (RFA). This study aims to evaluate the cost-effectiveness of CBA versus RFA in patients with drug-refractory PAF in China.Methods:A Markov model was developed to study the effects and the costs of CBA versus RFA. Cost and probability inputs data were obtained mainly from a real-world study of 85 CBA and 284 RFA patients treated in a tertiary hospital between July 2014 and July 2016. Propensity score matching was used to overcome retrospective bias, resulting in including 75 patients in each group. Input data gaps were closed with literature review and advisory board. A simulation was carried out for 14 cycles/years, and a discount rate of 3 percent was used. Then, a probabilistic sensitivity analysis was carried out with Monte Carlo approach.Results:In the base case scenario, the cumulative costs incurred by the CBA and RFA groups were CNY 132,222 (USD 20,767) and CNY 147,304 (USD 23,136), respectively. Over the 14-year period, the quality-adjusted life years (QALYs) gained by the CBA group was 7.85 versus 7.71 in the RFA group. The incremental cost-effectiveness ratio for CBA versus RFA was thus CNY 107,729 (USD 16,920)/QALY. Model results were most sensitive to the cost incurred during the first hospitalization, recurrence rate, and relative utility weights. The probability of CBA being cost-effective for willingness to pay thresholds of per capita GDP in China was estimated to be 99 percent.Conclusions:Compared with RFA, CBA is a cost-saving treatment providing increased QALYs. It represents good value for money for patients with drug-refractory PAF in China. However, further evidence needs to be generated from larger-scale studies in China.

Randomised clinical trial of cryoballoon versus irrigated radio frequency catheter ablation for atrial fibrillation—the effect of double short versus standard exposure cryoablation duration during pulmonary vein isolation (CIRCA-DOSE): methods and rationale

IntroductionPulmonary vein isolation (PVI) is an effective therapy for paroxysmal atrial fibrillation (AF), but it has limitations. The two most significant recent advances have centred on the integration of real-time...

Comparing cryoballoon and radio frequency ablation for atrial fibrillation treatment: A Hospital-based follow-up study

Aim: The aim is to evaluate the effectiveness and safety of cryoballoon ablation (CBA) for atrial fibrillation (AF) treatment, and compare it with radio-frequency ablation (RFA). Methods: A retrospective cohort study was conducted among AF patients who received CBA or RFA from November 2014 to January 2017 at The First Affiliated Hospital of Xi'an Jiaotong University. All patients were followed up from discharge date to either occurrence of death or April 2017. Results: Totally, 154 patients were identified who met the inclusion criteria of having episodes of electrocardiogram-documented AF within 2 months before hospitalization, 13 patients were excluded due to predetermined exclusion criteria, 29 (13 in the CBA group and 16 in the RFA group) were lost to follow-up, and 133 patients (57 in the CBA group and 76 in the RFA group) completed follow-up. The primary efficacy endpoints (AF recurrence or repeat ablation) occurred in 17 patients in the CBA group and 29 patients in RFA group (1-year Kaplan–Meier event-rate estimates, 33.2% and 37.9%, respectively; hazard ratio, 0.79; 95% confidence interval [CI], 0.43–1.5; P = 0.50). Long treatment success rate (no AF recurrence or repeat ablation during the follow-up) was 71.2% in CBA group and 64.6% in RFA, respectively (P = 0.47). The primary safety endpoints occurred in 10 patients in CBA group and 19 patients in the RFA group (1-year Kaplan–Meier event rate estimates, 17.3% and 21.2%, respectively; hazard ratio, 0.73; 95% CI, 0.34–1.57; P = 0.65). Conclusion: This paper presents the results of a first-ever study in a Chinese clinical setting and shows CBA had equivalent efficacy and safety in comparison to RAF as a treatment for AF. CBA is a promising new method for AF treatment.

Mechanistic Insights Into Durable Pulmonary Vein Isolation Achieved by Second-Generation Cryoballoon Ablation.

The mechanism explaining the efficacy of cryoballoon ablation (CBA) for atrial fibrillation has not been clarified. We compared lesion characteristics between patients in whom pulmonary vein isolation (PVI) was performed by CBA (n=56) and those by contact force (CF)-based RF ablation (n=56). We evaluated the 3-dimensional PV morphology before and after cryoballoon inflation. After PVI, a 3D left atrial voltage map was created. Pacing (10 mA and 2 ms) was performed within the low voltage area from the ablation line, and electrically unexcitable ablated tissue was identified. ATP-provoked dormant conduction after PVI occurred in 9 of the 224 (4%) PVs in the CBA group and in 13 of the 224 (6%) PVs in the CF group (P=0.3935). The inflated balloon stretched the PV from the original PV ostial surface by 7.1±3.5 mm, but at sites with (vs, sites without) residual PV potential/dormant conduction, the extent of the PV distension was reduced (4.0±4.0 mm vs. 7.2±3.4 mm, P<0.0001). The unexcitable ablated tissue around the PVs was significantly wider in CB patients than in CF patients (16.7±5.1 mm vs. 5.3±2.3 mm, P<0.0001). Use of the cryoballoon significantly distends the PV. Without this extensive distention, PVI may not be successful. CBA seems to yield wide unexcitable ablation zones. These factors seem to explain the durability of CBA lesions.

VP122 Cryoballoon Versus Radiofrequency Ablation For Atrial Fibrillation

INTRODUCTION:Pulmonary vein isolation (PVI) is a new effective treatment for atrial fibrillation (AF) (1). The standard of care for ablation methods using radiofrequency (RF) is time-consuming and technically challenging (2), and restricted to a few specialized centers, which causes the limited availability of ablation therapy (3). Therefore, cryoballoon (CB) ablation has been developed to shorten and simplify the procedure. The objective of this systematic literature review and meta-analysis was to compare the effectiveness of cryoballoon ablation (CBA) with radiofrequency ablation (RFA) for the treatment of AF.METHODS:We searched the Cochrane Library and PubMed from 2009 to October 2016 to screen the eligible literature according to the inclusion and exclusion criteria. The effectiveness measures were the acute pulmonary vein (PV) isolation rate, procedure time, complications and the proportion of patients free from AF (follow-up &gt; 3 months). Meta-analysis and descriptive statistics were used in this study.RESULTS:A total of seventeen articles with 5,806 cases (2,288 from CBA group, 3,518 from RFA group) from seven different countries were reviewed and analyzed. Pooled analyses indicated that CBA was more beneficial in terms of procedural time (Standard mean difference, SMD = -.501; 95%CI: -.893– -.109; P&lt;.05) for RFA; but the acute PV isolation rate (Odds ratio, OR = .06; 95 percent Confidence Interval, CI: .03–.13; P &lt; .05) in RFA was higher than for CBA; also, after median follow-up of 14 months (range 9–28 months), the proportion of patients free from AF (OR = .965; 95 percent CI:.859—1.085; P = .554) and the total complication rates (OR = .937; 95 percent CI:.753–1.167; P = .562) were not significantly different between CBA and RFA.In the four randomized controlled trials (RCTs) of the seventeen studies, the proportion of patients free from AF (OR = .951; 95 percent CI:.752–1.202; P = .672) and the complications (OR = 1.521; 95 percent CI:.570–4.058; P = .402) were not significantly different between CBA and RFA.CONCLUSIONS:Overall, compared with RFA for the treatment of patients with AF, CBA had similar clinical effectiveness on the proportion of people free from AF and the number of complications, and yet greater improvement in total procedure time referred for CBA and higher acute PVI rate referred for RFA.