Novel usage of the cryoballoon catheter to achieve large area atrial substrate modification in persistent and long-standing persistent atrial fibrillation

An evaluation of the clinical efficacy of the application of 28mm cryoballoon for linear ablation of left atrial apex combined with enlarged pulmonary vein vestibule ablation for persistent atrial fibrillation

OBJECTIVE

to retrospectively investigate the efficacy and safety of the application of 28 mm cryoballoon for pulmonary vein electrical isolation (PVI) combined with top left atrial linear ablation and pulmonary vein vestibular expansion ablation for persistent atrial fibrillation.

METHODS

From July 2016 to December 2020, 413 patients diagnosed with persistent atrial fibrillation were evaluated, including 230 (55.7%) in the PVI group (PVI only) and 183 (44.3%) in the PVIPLUS group (PVI plus ablation of the left atrial apex and pulmonary vein vestibule). The safety and efficacy of the two groups were retrospectively analyzed.

RESULTS

The AF/AT/AFL-free survival rates at 6, 12, 18, 24 and 30 months after procedure was 86.6%, 72.6%, 70.0%, 61.1% and 56.3% in the PVI group and 94.5%, 87.0%, 84.1%, 75.0% and 67.9% in the PVIPLUS group, respectively. At 30 months after procedure, the AF/AT/AFL-free survival rate was significantly higher in the PVIPLUS group than in the PVI group (P = 0.036; HR:0.63; 95% CI:0.42 to 0.95).

CONCLUSION

The application of 28-mm cryoballoon for pulmonary vein electrical isolation combined with linear ablation of the left atrial apex and expanded ablation of the pulmonary vein vestibule improves the outcome of persistent atrial fibrillation.

WITHDRAWN: Prevalence and factors associated with smoking in a nationally representative sample of Greek adults: The Hellenic National Nutrition and Health Survey (HNNHS)

The Publisher regrets that this article is an accidental duplication of an article that has already been published, https://doi.org/10.1016/j.hjc.2022.05.005. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal

The feasibility and safety of substrate modification on the left atrial roof area using a cryoballoon in atrial fibrillation ablation

BACKGROUND

Data on additional substrate modification using a cryoballoon beyond cryoballoon pulmonary vein isolation (CB-PVI) is limited. We sought to evaluate the efficacy and safety of substrate modification on the left atrial roof area using CBs (LAR-CBs) for atrial fibrillation (AF) patients.

METHODS

Eighty-one AF patients (70.0[62.5-77.0] years, 33 paroxysmal AF[PAF], 48 non-PAF) underwent LAR-CBs following CB-PVIs. Voltage maps were created with a high-resolution mapping system. Roof line conduction block was evaluated during the repeat procedure.

RESULTS

The total number of applications for the CB-PVI and LAR-CB were 5.0 ± 1.2 and 3.8 ± 0.7, and both were significantly greater in non-PAF than PAF patients. LA roof areas had continuous scar in 61/79(77.2%) patients, and the mean balloon temperature was significantly lower in patients with continuous scar than those without (-39.3 ± 3.8 vs. 36.0 ± 4.6 °C, p = 0.004). The single procedure 1-year AF freedom was 87.6% (7.5% on antiarrhythmic drug) and was similar between PAF and non-PAF patients (p = 0.14). Twelve (14.8%) patients underwent a second procedure 5.5(2.2-7.5) months later, and a mean of 1.3 ± 0.5 PVs were reconnected in 7/12(58.3%) patients. Electrical conduction block across the roof line was proven in 3/12(25.0%) patients. There were 6(7.4%) complications related to the procedures, including iatrogenic roof dependent atrial tachycardia, takotsubo cardiomyopathy, and severe pericarditis in 1, 1, and 2 patients, respectively.

CONCLUSIONS

LA roof area substrate modification using CBs yielded a high arrhythmia freedom after single procedures. However, a low incidence of electrical conduction block across the line during the chronic phase and delayed complications were the major concerns.

Pulmonary vein isolation for atrial fibrillation: Does ablation technique influence outcome?

BACKGROUND

Over the last 20 years various techniques have been developed striving for safer and more durable pulmonary vein isolation (PVI). The three most commonly used tools are pulmonary vein ablation catheter (PVAC) and cryoballoon ('single-shot' techniques), and point-by-point (PBP) radiofrequency ablation using 3D electroanatomical mapping (EAM).

OBJECTIVE

Evaluate the safety and efficacy of the different techniques in an unselected population undergoing de-novo ablation for persistent or paroxysmal atrial fibrillation (AF) at Royal Papworth Hospital (RPH).

METHOD

Retrospective, single-centre study of consecutive AF ablations at RPH between March 2017 and April 2018. Demographic, procedural and outcome data were analysed.

RESULTS

Over the study period 329 first-time PVI procedures were performed. 37.4% were performed using PBP, 39.8% using cryoballoon and 22.8% using PVAC. There was no significant difference in age or sex between different ablation technique groups. 238 procedures were performed for paroxysmal AF and 91 for persistent AF. A higher proportion of the persistent cases were performed using point-by-point techniques compared to paroxysmal cases (58.2% vs 29.0%, p < 0.05). Procedural times were significantly longer in the group undergoing PBP ablation compared to cryoballoon or PVAC. However, there was no statistically significant difference in 12-month freedom from symptomatic AF or procedural complications between the groups.

CONCLUSIONS

PBP, PVAC and cryoballoon AF ablation all appeared equally efficacious in an unselected population, though PVAC and cryoballoon procedures were shorter. All procedures were associated with a low adverse event rate. Prospective examination is required to substantiate this finding.

Segmental nonocclusive cryoballoon ablation of pulmonary veins and extrapulmonary vein structures: Best practices III

Although cryoballoon ablation of atrial fibrillation (AF) traditionally has been guided by pulmonary vein (PV) occlusion, there is evidence and growing interest in performing segmental, nonocclusive cryoballoon ablation to target not only large/common PVs but extra-PV structures such as the left atrial (LA) roof and posterior wall in conjunction with PV isolation. A number of studies have demonstrated improved clinical efficacy associated with nonocclusive cryoballoon ablation of the LA roof and posterior wall in addition to PV isolation, particularly in patients with persistent AF. Not only can the cryoballoon be used for targeting extra-PV structures through segmental, nonocclusive ablation, but the large size and durability of cryolesions coupled with the enhanced stability afforded through cryoadhesion render the cryoballoon an effective tool for such an approach. This article reviews the rationale and practical approach to segmental, nonocclusive cryoballoon ablation of large/common PV antra and the LA roof and posterior wall.

Cryoballoon ablation for extrapulmonary vein targets

PURPOSE OF REVIEW

Cryoballoon catheter can create large and contiguous lesions with stable contact during ablation. It has proven to be well tolerated and effective in pulmonary vein isolation. But atrial arrhythmias, including atrial fibrillation, atrial tachycardia, and atrial flutter (AFL), also relate to many extrapulmonary vein targets. It is necessary to understand the current evidence for the use of cryoballoon ablation for targets outside of pulmonary veins.

RECENT FINDINGS

Studies have shown that the cryoballoon ablation can be used in extrapulmonary vein area, including left atrium roof, left atrial appendages, posterior left atrial wall, mitral isthmus, and right atrial appendage. The results indicate cryoballoon ablation is an effective and well-tolerated treatment option for the atrial arrhythmias in these locations outside of pulmonary vein when clinical necessary.

SUMMARY

The cryoballoon ablation can safely and effectively perform contiguous linear lesions, structure isolations, and local ablation for targets outside of the pulmonary veins.

Magnetic resonance imaging-guided cryoballoon ablation for left atrial substrate modification in patients with atrial fibrillation

BACKGROUND

Cryoballoon ablation (CBA) for pulmonary vein isolation (PVI) is an established modality for the treatment of atrial fibrillation (AF). We report feasibility of left atrial (LA) substrate modification in addition to PVI both using the cryoballoon.

METHODS

LA substrates and CBA-induced scar were assessed at baseline and 3 months after ablation using late gadolinium enhancement magnetic resonance imaging (LGE-MRI). Common periprocedural data including postablation LGE-MRI for evaluation of esophageal thermal injury, and CBA-associated complications were collected. Freedom from AF recurrence at 12 months was assessed using Holter and 30-day rhythm monitors.

RESULTS

In 26 patients (64 ± 11 years, 69% male; 27% persistent AF, CHADSVASC score: 2.3 ± 1.5; left ventricular ejection fraction: 56 ± 10%, oral anticoagulation with warfarin/direct oral anticoagulants: n = 11/15), referred for first-time AF ablation, CBA of the pulmonary veins and extrapulmonary LA substrates was performed (median: 12 [interquartile range {IQR}: 7-14] freezes over 1675 seconds [IQR: 1168-2160]). On LGE-MRI, significant postablation cryoballoon-induced LA scar (median: 19.4% [IQR: 13.4-24.7] in comparison to baseline preablation LA-LGE (median: 10.6% [IQR 3.1-13.1]; P = .01) was found. Freedom from AF recurrence at 12 months was 74.5% with median time-to-recurrence of 242 days (IQR: 172-298). In 15 of 26 (58%) patients, esophageal enhancement on the postablation MRI was present with full recovery after 3 months. No major periprocedural complications were observed.

CONCLUSION

LA substrate modification in addition to PVI using LGE-MRI-guided CBA is feasible but still experimental. The efficacy and safety have to be investigated in a prospective randomized trial.

Successful cryoballoon ablation of a focal atrial tachycardia in a patient with situs inversus and dextrocardia

Cryoballoon ablation of an arrhythmogenic focus alongside a pulmonary vein as an alternative to radiofrequency ablation may be feasible and safe in patients with situs inversus and dextrocardia.

Comparing radiofrequency and cryoballoon technology for the ablation of atrial fibrillation

PURPOSE OF REVIEW

With the growing popularity of the cryoballoon tool for catheter ablation of atrial fibrillation, there has been discussion of whether cryothermal energy is just as or more effective than traditional radiofrequency. This review will compare both thermal energies for the treatment of atrial fibrillation.

RECENT FINDINGS

Although the FIRE and ICE trial established that cryoballoon technology is noninferior to radiofrequency ablation for the treatment of atrial fibrillation, both thermal technologies have undergone advancement. This review intends to explore recent changes in technology and catheter ablation technique to improve outcomes for patients with atrial fibrillation.

SUMMARY

Catheter ablation is standard treatment for patients with atrial fibrillation, which primarily focuses on electrical isolation of the pulmonary veins. Radiofrequency is the most common approach at present times; however, over time, new technology has developed. Most successful among these is the cryoballoon tool. Although the FIRE and ICE trial indicated radiofrequency and cryothermal energy to be approximately equal in efficacy and safety, there are advantages and disadvantages to both. This review seeks to address the value of each tool, as well as further development needed to better address atrial fibrillation while improving procedural safety.

Cryoballoon ablation beyond paroxysmal atrial fibrillation

PURPOSE OF REVIEW

Although radiofrequency-based pulmonary vein isolation (PVI) was considered the 'gold standard' for the treatment of atrial fibrillation for a long time, the cryoballoon has turned out to be a common alternative tool for atrial fibrillation ablation. Most of the data regarding cryoballoon-based ablation relate to patients with paroxysmal atrial fibrillation (PAF). In this review, we summarize recent knowledge on the usage of cryoballoon ablation for other conditions, especially persistent atrial fibrillation.

RECENT FINDINGS

The cryoballoon is an effective ablation tool for PVI. As PVI is the first-line recommended procedural endpoint in atrial fibrillation ablation, it can be recommended not only for the treatment of PAF but also persistent atrial fibrillation and results in satisfying clinical outcomes. Recently, smaller studies and case reports were published reporting on cryoballoon ablation strategies beyond stand-alone PVI. These studies report a wide application spectrum of the cryoballoon and therefore potentially increase clinical success as well as the patient collective amenable to cryoballoon ablation.

SUMMARY

Cryoballoon-based PVI can be recommended not only for patients with PAF but also for patients with persistent atrial fibrillation. Ablation strategies going beyond PVI need further evaluation, but might expand the use of the cryoballoon.

The safety and efficacy of second-generation cryoballoon ablation plus catheter ablation for persistent atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Growing evidence suggests that second-generation cryoballoon ablation (2G-CB) is effective in patients with persistent atrial fibrillation (PerAF). The cornerstone of atrial fibrillation (AF) ablation is pulmonary vein isolation (PVI). The purpose of this study was to summarize the available data on the safety and mid-term (≥ 12 months) effectiveness of a 'PVI-only' strategy vs. a 'PVI-plus' strategy using 2G-CB in patients with PerAF.

METHODS

We searched the PubMed, EMBASE and Cochrane library databases for studies on 2G-CB for PerAF. Group analysis was based on the ablation approach: 'PVI-only' versus 'PVI-plus', the latter of which involved PVI plus other substrate modifications. Studies showing clinical success rates at a follow-up (FU) of ≥ 12 months were included. Complication rates were also assessed. Data were analyzed by applying a fixed effects model.

RESULTS

A total of 879 patients from 5 studies were analyzed. After a mid-term FU of 27 months, the overall success rate of 2G-CB for PerAF was 66.1%. In the 'PVI-plus' group, the success rate was 73.8%. In the 'PVI-only' group, the success rate was 53.6%. No heterogeneity was noted among studies (I2 = 0.0%, P = 0.82). Complications occurred in 5.2% of patients (P = 0.93), and the rate of phrenic nerve (PN) injury was 2.8% (P = 0.14). Vascular assess complications were the most frequent at 1.6% (P = 0.33). No death or myocardial infarction was reported.

CONCLUSION

'PVI-plus' involving 2G-CB seems to be safe and effective for treating PerAF.

Atrial fibrillation ablation using cryoballoon technology: Recent advances and practical techniques

Atrial fibrillation (AF) affects 1-2% of the population, and its prevalence is estimated to double in the next 50 years as the population ages. AF results in impaired patients' life quality, deteriorated cardiac function, and even increased mortality. Antiarrhythmic drugs frequently fail to restore sinus rhythm. Catheter ablation is a valuable treatment approach for AF, even as a first-line therapy strategy in selected patients. Effective electrical pulmonary vein isolation (PVI) is the cornerstone of all AF ablation strategies. Use of radiofrequency (RF) catheter in combination of a three-dimensional electroanatomical mapping system is the most established ablation approach. However, catheter ablation of AF is challenging even sometimes for experienced operators. To facilitate catheter ablation of AF without compromising the durability of the pulmonary vein isolation, "single shot" ablation devices have been developed; of them, cryoballoon ablation, is by far the most widely investigated. In this report, we review the current knowledge of AF and discuss the recent evidence in catheter ablation of AF, particularly cryoballoon ablation. Moreover, we review relevant data from the literature as well as our own experience and summarize the key procedural practical techniques in PVI using cryoballoon technology, aiming to shorten the learning curve of the ablation technique and to contribute further to reduction of the disease burden.

Practical Techniques in Cryoballoon Ablation: How to Isolate Inferior Pulmonary Veins

Catheter ablation is the most effective treatment option for patients suffering from symptomatic atrial fibrillation. Electrical isolation of the pulmonary veins is the procedural cornerstone. Point-by-point radiofrequency current energy ablation in combination with a 3D electro-anatomical mapping system is the established approach to ablation. In contrast, cryoballoon ablation uses a single-shot approach to facilitate pulmonary vein isolation. However, fixed cryoballoon diameters (28 mm or 23 mm) and non-balloon compliance can lead to technical difficulties in isolating variable pulmonary vein anatomies. This review focuses on key procedural aspects and illustrates practical techniques in cryoballoon pulmonary vein isolation to shorten the learning curve without compromising safety and efficacy. It has a special emphasis on inferior pulmonary veins.

Second generation cryoballoon ablation for persistent atrial fibrillation: an updated meta-analysis

BACKGROUND

Catheter ablation is an established treatment option for patients with symptomatic atrial fibrillation (AF). The cornerstone of AF ablation is pulmonary vein isolation (PVI). The second-generation cryoballoon (2G-CB) has shown non-inferiority to radiofrequency (RF) ablation in paroxysmal AF in several trials. Growing evidence suggests that 2G-CB is also effective in patients with persistent AF (perAF). The aim of this study was to summarize and analyze available data on safety and mid-term (≥ 12 months) efficacy of PVI using 2G-CB in patients with perAF.

METHODS

We did a search in PubMed, Web of Science, Cochrane Library, and clinicaltrials.gov in December 2016 for studies of 2G-CB ablation for perAF. Studies reporting clinical success rates at a follow-up (FU) of ≥ 12 months were included. Success was defined as freedom from any atrial arrhythmia lasting > 30 s after an initial blanking period of 3 months. Acute success and complication rates were also assessed. Data were analyzed applying random-effects model.

RESULTS

A total of 917 patients from 11 studies meeting study inclusion criteria were analyzed. After a mean FU of 16.7 ± 3.0 months, 68.9% were free from recurrences [95% confidence interval (CI) 63.4-74.7%]. Overall acute success rate was 99.7% (95% CI 99.2-100%). Complications occurred in 5.5% (95% CI 2.4-9.6%). Vascular access complications were the most frequent 3.3% (95% CI 1.5-5.6%). The rate of phrenic nerve palsy/injury was 2.09% (95% CI 0.8-3.9%). No death, stroke or myocardial infarction was reported.

CONCLUSION

The 2G-CB seems to be safe and effective in the treatment of perAF in the mid-term.