Kaoru Okishige

Background: Cryoballoon pulmonary vein (PV) isolation (PVI) requires PV occlusion, which can be challenging to the large PV. The non‐occlusive separate freezing, which involves freezing the superior and inferior portions of the PV ostium without complete occlusion, is often useful in these situations. This study aimed to evaluate the efficacy and long‐term results of the non‐occlusive separate freezing technique and compare the treatment details of POLARx and Arctic Front Advance Pro (AFA‐Pro).Methods: Patients who underwent cryoballoon PVI using the non‐occlusive separate freezing between September 2019 and April 2023 in our institution were analyzed and followed up for 1 year. Success rates of PVI by non‐occlusive separate freezing and treatment outcomes were compared between POLARx and AFA‐Pro. The 1‐year arrhythmia‐free survival was also evaluated.Results: Overall, 135 PVs were analyzed (POLARx, n = 63; and AFA‐Pro, n = 72). The success rates of PVI for the POLARx and AFA‐Pro were 55/63 (87.3%) and 52/72 (72.2%), p = 0.04. The nadir temperatures for the POLARx and AFA‐Pro were −52.2 ± 4.7°C and −42.4 ± 7.4°C, p < 0.001. No phrenic nerve injury occurred in either group, but two cases of gastric hypomotility were observed using POLARx. The 1‐year arrhythmia‐free survival rates for POLARx and AFA‐Pro were 86.4% and 81.2%, p = 0.47.Conclusions: The success rate of PVI using the non‐occlusive separate freezing technique was approximately 80% and was significantly higher with POLARx than with AFA‐Pro. The 1‐year arrhythmia‐free survival rate was not significantly different.

Ablation using a cryoballoon can minimize the number of sheaths passing through a permanent inferior vena cava filter (pIVCF). Cryoballoon ablation with only a few sheaths can be safely and efficiently performed via the usual femoral vein approach in patients with atrial fibrillation and pIVCF.

Background: The novel POLARx cryoballoon ablation (CBA) system offers enhanced cooling properties for the treatment of atrial fibrillation (AF); however, these capabilities may damage adjacent tissues. This study aimed to assess the prevalence and predictors of gastric hypomotility (GH) in patients undergoing pulmonary vein isolation (PVI) and left atrial (LA) roofline ablation using the POLARx. Methods: Patients who underwent CBA for PVI using the POLARx system were included in this study. Additional LA roofline ablation was performed in patients with non‐paroxysmal AF and paroxysmal AF with LA enlargement. GH occurrence was assessed postoperatively by esophagogastroscopy, and the distance between the esophagus and surrounding tissues were measured. Results: Among the 61 patients who underwent PVI, 22 underwent additional LA roofline ablation. GH was confirmed in 12 patients (30.8%) who underwent PVI only and 12 patients (54.5%) who underwent additional LA roofline ablation. Symptomatic GH with acute gastric dilation occurred in three patients, all of whom had undergone roofline ablation. Multivariate analysis, a shorter distance between the esophagus and the midpoint of the vertebral body (odds ratio, 0.74; 95% confidence interval, 0.55–0.98; p = 0.04) was identified as the sole predictor of GH, with a cutoff of 20.0 mm (sensitivity, 80.0%; specificity, 81.8%). Conclusion: Adding LA roofline ablation to PVI using the POLARx may increase the risk of GH, particularly when the esophagus is in close proximity to the midpoint of the vertebral body.

Background: The effectiveness of cryoballoon ablation (CBA) of the left atrial (LA) roof in addition to pulmonary vein isolation (PVI) using a novel cryoballoon catheter, POLARx, remains unclear.Methods: This study compared the efficacy of LA roof line ablation and PVI using POLARx (Boston Scientific) or AFA‐Pro (Medtronic) in 100 patients with persistent atrial fibrillation. The right superior pulmonary vein (PV) anchoring and raise‐up techniques were consistently used for LA roof line ablation, and rapid right ventricular pacing was applied if the cryoballoon temperature did not reach −40°C.Results: Complete conduction block at the LA roof could be obtained in all patients with POLARx and in 98.0% of patients with AFA‐Pro. Rapid right ventricular pacing was needed in 64.0% of patients with AFA‐Pro and in no patients with POLARx. During LA roof line ablation, the nadir cryoballoon temperature was significantly lower with POLARx than with AFA‐Pro (right: −54.2°C ± 4.4°C vs. −46.0°C ± 5.4°C; central: −56.8°C ± 4.4°C vs. −45.7°C ± 4.8°C; left: −56.1°C ± 4.3°C vs. −46.1°C ± 5.7°C), and the cryoballoon temperature reached −40°C earlier with POLARx than with AFA‐Pro (right: 30.8 ± 7.4 s vs. 74.1 ± 37.7 s; central: 28.2 ± 5.2 s vs. 62.9 ± 30.9 s; left: 29.8 ± 5.8 s vs. 69.6 ± 40.7 s).Conclusion: The nadir cryoballoon temperature with POLARx was approximately 10°C lower than with AFA‐Pro, consistently dropping below −40°C during LA roof line CBA. Thus, a complete conduction block of the LA roof line can be easily accomplished using right superior PV anchoring and the raise‐up techniques without the need for rapid right ventricular pacing with POLARx.

Introduction: Gastric hypomotility (GH) is a major complication of atrial fibrillation (AF) ablation. We aimed to clarify whether additional cryoballoon ablation (CBA) of the left atrial (LA) roof is associated with GH. Methods and Results: This study included 54 patients with non-paroxysmal AF who underwent CBA for pulmonary vein isolation and of the LA roof line. GH was defined according to the results of esophagogastroscopy performed 2 days after ablation. GH was observed in 10 patients. There were significant differences in LA diameter (LAD), right inferior pulmonary vein (RIPV) diameter, and the height of the LA roof from the point where the LA posterior wall and esophagus make contact between patients with (GH+) and without GH (GH–) (LAD: 41.0 [36.3–41.8] mm vs. 46.5 [42.8–50.0] mm, p<0.01; RIPV diameter: 19.7 [19.0–20.5] mm vs. 23.2 [21.2–24.9] mm, p<0.01; height of LA roof: 5.7 [5.1–6.1] mm vs. 8.8 [7.1–11.2] mm for, p<0.01, respectively). Multivariate analysis revealed that LA roof height was a predictor of GH. Moreover, Patient Assessment of Upper Gastrointestinal Disorders-Symptom Severity Index (PAGI-SYM) scores increased significantly 1 week after ablation (from 1.0 [0.0–2.8] to 5.0 [3.0–11.0], p=0.03) in patients with GH. Conclusion: The height of the LA roof may be a predictor of GH after CBA of the LA roof line. Additionally, GH-related symptoms may still appear 1 week after ablation.

Introduction: Cryoballoon ablation (CBA) of the left atrial (LA) roof in addition to a pulmonary vein isolation has been expected to improve the clinical outcomes post‐atrial fibrillation (AF) ablation. We demonstrated the characteristics and efficacy of CBA of the LA roof through our experience with a large volume of procedures.Methods: Among 1036 AF ablation procedures with CBA of the LA roof, 834 patients who underwent a de novo ablation were analyzed.Results: Complete LA roof line conduction block was obtained in 767 patients (92.0%) solely by CBA (Group A). Compared with the other patients (Group B), the mean nadir balloon temperature during CBA of the LA roof (−44.5 ± 5.6°C for Group A vs. −40.5 ± 7.5°C for Group B, p < .01) and number of cryoballoon applications during the LA roof ablation with a circular mapping catheter located in the left superior pulmonary vein (1.3 ± 0.8 for Group A vs. 1.6 ± 1.0 for Group B, p = .02) were significantly lower in Group A. A multivariate analysis revealed that those were predictors of a complete LA roof conduction block after only CBA. The 1‐year Kaplan–Meier atrial arrhythmia free rate estimates were 80.6% for Group A and 59.0% for Group B (p < .01).Conclusion: Complete LA roof line conduction block could be obtained with a cryoballoon without touch‐up ablation in most cases. The LA roof CBA with a circular mapping catheter located in the right superior pulmonary vein was preferable to obtaining complete LA roof conduction block, which was important with regard to the clinical outcomes.

BackgroundsCatheter ablation for non-paroxysmal atrial fibrillation (non-PAF) remains challenging and more effective strategy has been required to reduce postoperative arrhythmia recurrences. This study aims to investigate the efficacy and safety of a novel extensive ablation strategy for non-PAF, that is based on a combination of cryoballoon (CBA), radiofrequency (RFA), and Marshall-vein ethanol ablations (EA-VOM). MethodsThe study was a single-center, retrospective observational study. We enrolled 171 consecutive patients who underwent de-novo catheter ablation for non-PAF under conscious sedation with a novel extensive ablation strategy that included CBA for pulmonary vein isolation (PVI) and left atrial roof ablation (LARA), RFA for mitral isthmus (MI) ablation, superior vena cava isolation, and other linear ablations and EA-VOM. Recurrence of atrial arrhythmias over 1 year, procedure outcomes, and procedure-related complications were investigated. ResultsA total of 139 (81.3%) patients remained in sinus rhythm during 1-year follow-up. Of the 139 patients, 51 patients (29.8%) received antiarrhythmic drugs. The mean procedure time was 204 +/- 45 min. PVI and LARA ablation by CBA and MI block by RFA and EA-VOM were completed in 171 (100%) and 166 (97.1%) patients, respectively. No serious procedure-related complications were observed except for one case of delayed pericardial effusion. ConclusionApproximately 80% of the study patients were AF-free during 1-year follow-up period after a single procedure based on the novel extensive ablation strategy combining CBA, RFA, and EA-VOM. This strategy for non-PAF may be preferred in terms of maintenance of sinus rhythm, safety even in high-risk patients, and relatively short procedure time.