Adenosine-guided pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation: an international, multicentre, randomised superiority trial

Very High-Power Short-Duration Ablation for Atrial Fibrillation in Adults With Congenital Heart Disease

INTRODUCTION

Data regarding safety and long-term outcome of very high-power-short duration (vHPSD) ablation in adult congenital heart disease (ACHD) patients with paroxysmal or persistent atrial fibrillation (AF) are lacking.

METHODS

Retrospective observational single-center study. The data of 66 consecutive ACHD patients (mean age 60 ± 12.8 years, 46% male) with mild (69.7%), moderate (22.7%), or complex (7.6%) congenital heart disease (CHD) who underwent ablation for paroxysmal (40.9%) or persistent AF (59.1%) were analyzed. Circumferential PVI was performed in all patients and additional substrate ablation in 79,4% of persistent AF patients using irrigated RF energy with vHPSD settings of 70 W/5-7 s or 60 W/7-10 s.

RESULTS

Mean procedure time was 123.6 ± 42 min with a mean RF time of 18.19 ± 10 min. No technique related adverse events occurred. Vascular access complications were detected in seven patients (10.6%) requiring intervention in four patients (6%). A median follow-up time of 491 days (IQR: 194-1054 days). Freedom from any atrial arrhythmia off antiarrhythmic drugs (AAD) at 1 year was present in 58% of patients (77.8% with paroxysmal AF, 43.6% with persistent AF).

CONCLUSION

vHPSD for ablation of paroxysmal or persistent AF in ACHD patients is safe and effective. Regardless of CHD complexity, no vHPSD ablation modality related complications occurred. Long-term outcome for paroxysmal AF after one ablation was excellent whereas results for persistent AF were limited.

The relationship between the 3D electroanatomical mapping parameters of the left atrial posterior wall and the recurrence of paroxysmal atrial fibrillation

Background

Pulmonary vein isolation (PVI) remains the cornerstone of catheter ablation in paroxysmal atrial fibrillation (PAF). However, the recurrence of AF after PVI needs further investigation. The left atrial posterior wall (LAPW) is embryologically related to the pulmonary vein and plays an important role in the initiation and maintenance of AF. This study aims to explore the relationship between the 3D electroanatomical mapping parameters of the LAPW and recurrence in patients with PAF.

Methods

A retrospective analysis was conducted on patients with PAF who underwent PVI. Both clinical and procedural characteristics from the enrolled subjects were collected before PVI. 3D electroanatomical mapping anatomical and electrical parameters were measured and calculated in the CARTO system. Intergroup comparisons and multivariate logistic regression analysis were performed to demonstrate the relationship between the parameters of LAPW and AF recurrence. A combined prediction model for AF recurrence was constructed in this study.

Results

A total of 120 patients were included in the final analysis. Among procedural characteristics, compared with Group 1 (no recurrence), there was a significantly larger posterior wall surface area (PWSA) (p = 0.013) and a percentage of very low-voltage area (PVLVA) (p < 0.001) in Group 2 (recurrence). Further analysis revealed that there was a significant difference between the two groups in terms of the distribution of VLVA (p = 0.026). Subsequently, in a multivariate logistic regression analysis, both PWSA and PVLVA were found to be independent risk factors for AF recurrence [odds ratio (OR): 1.457, 95% confidence interval (CI): 1.037-2.049, p = 0.030; OR: 1.059, 95% CI: 1.013-1.107, p = 0.012, respectively]. Finally, a prediction model that combined the PWSA with the PVLVA for AF recurrence was constructed to draw the receiver operating characteristic curve. The area under the curve of this model was 0.900 (0.827-0.973) (p < 0.001). The result, evaluated by using the Hosmer-Lemeshow goodness-of-fit test, showed that χ2 = 4.643 (p = 0.796).

Conclusions

This study demonstrates that both PWSA and PVLVA were independent risk factors for AF recurrence. Moreover, we proposed a model that combined the PWSA with the PVLVA to predict the recurrence of AF, which may provide an approach for screening patients with PAF who may require attention for the LAPW.

Comparison of ex vivo lesion formation for two adjacent radiofrequency applications with very high-power short-duration in various inter-lesion times

Background/Objectives

Very high-power and short-duration (vHPSD) ablation with QDOT MICRO™ facilitates speedy and safe ablation for pulmonary vein isolation. A brief time interval between ablating two neighboring sites with vHPSD may potentially influence the size and geometry of the lesions. This study evaluates lesion formation when delivering adjacent applications using vHPSD at various inter-lesion times (ILTs).

Methods

Radiofrequency applications were conducted by QDOT MICRO™ catheter with 90 W of strength and 4 s duration. Fresh swine heart tissue on the epicardium was ablated with 10 g of the contact force. Lesions were created using a single application (SA) and double applications (DA) of adjacent lesions with a 6 mm distance between them as measured on the 3D mapping system. The DA was performed with various ILTs, 60 s (DA-60 s), 10 s (DA-10 s), 5 s (DA-5 s), and 0 s (DA-0 s).

Results

Out of 90 lesions, 79 were analyzed. Eleven lesions were excluded for one steam pop event, seven out of the target distance, and three divided lesions of two applications. There were no significant differences in surface diameter, cross-sectional diameter, and maximal lesion depth in each application among the groups. The intermediate lesion depth was significantly more profound in groups with shorter and immediate ILT (DA-10, 5, and 0 s) compared to the group with a prolonged ILT between two applications (DA-60 s) (2.99, 3.03, 3.16 mm vs. 2.42 mm, respectively; p < .001).

Conclusions

Two adjacent radiofrequency applications with vHPSD in short ILT may result in deeper lesions in the middle of combined double lesions.

Cryoballoon pulmonary vein isolation: Double stack vs standard ablation

BACKGROUND

The results of pulmonary vein isolation (PVI) are limited by arrhythmia recurrence, which is most often due to failure to effectuate a durable contiguous circumferential transmural lesion around the pulmonary vein ostia.

OBJECTIVE

We sought to determine if enhancing the index ablation line through the use of multiple cryoballoon diameters would be superior to standard ablation with bonus freeze.

METHODS

We enrolled 226 consecutive patients referred for cryoballoon-based PVI. Patients underwent PVI either with the 28-mm Arctic Front Advance (Medtronic, Minneapolis, Mn) cryoballoon using two 4-minute freezes (standard group) or with the POLARx FIT (Boston Scientific, Marlborough, Ma) cryoballoon using 3-minute freezes in both the 28- and 31-mm-diameter configurations (double stack group). Patients were followed for up to 1 year. The primary outcome was atrial tachyarrhythmia recurrence, with peri-procedural complications, cardioversion, emergency department visit, hospitalization, and repeat ablation being secondary outcomes.

RESULTS

A total of 226 patients were included (70% male; 47% with persistent atrial fibrillation [AF]). Patients in the double stack group had a significantly greater freedom from recurrent AF/atrial tachycardia/atrial flutter at 1 year (87.2% vs 68.9%; hazard ratio 0.41; 95% confidence interval 0.24-0.71; P=.008). Periprocedural complications were similar between the groups (5.2% vs 3.4%; P=.50). At 1 year, there was no difference in cardioversion (12.8% vs 20.3%; P=.20), emergency department visit (9.0% vs 15.5%; P=.22), or all-cause hospitalization (1.3% vs 2.7%; P=.66). Significantly less patients treated with double stack underwent repeat ablation (1.3% vs 13.5%; P=.002).

CONCLUSION

In a mixed cohort of patients with paroxysmal and persistent AF, cryoballoon ablation using the double stack technique is associated with lower rates of AF recurrence, aggregate healthcare utilisation, and lower rates of repeat ablation.

Representation of Women in Atrial Fibrillation Ablation Randomized Controlled Trials: Systematic Review

BACKGROUND

Sex inequality in randomized controlled trials (RCTs) related to cardiovascular disease has been observed. This study examined the proportion of women enrolled in atrial fibrillation (AF) ablation RCTs and the potential risks of underrepresentation of women.

METHODS AND RESULTS

We systematically searched PubMed and Embase for AF ablation RCTs published from 2015 to 2022. Participant characteristics were compared among trials with higher and lower proportions of women. Of 147 AF ablation RCTs (30,055 participants), only 10 trials had enrolled women ≥50% of the total participants. Additionally, 42 trials (28.57%) excluded pregnant/breastfeeding women; 6 (4.1%) excluded reproductive-age women without reliable birth control. The proportion of women in AF RCTs ranged from 9% to 71% (median 31.5%), whereas the median proportion of men was 67.7%. The rate of women included in the trials was stable from 2015 to 2022 (P=0.49). Study characteristics, including funding source, showed no correlation with the rate of inclusion of women. RCTs with a higher proportion of female participants enrolled older patients with AF, had a higher prevalence of hypertension but less persistent AF, and smaller left atrium size (P<0.05 for all). Biological sex was evaluated as a risk factor or in a subgroup analysis in 28 RCTs; 10.7% of these trials observed the implication of sex on their results.

CONCLUSION

Women were underrepresented in contemporary AF ablation RCTs. Additionally, women enrolled in AF RCTs were likely to have more comorbidities but less advanced AF, limiting the applicability of the results to women with AF.

Prognostic Value of Burst Pacing Inducibility Post-Radiofrequency Versus Cryoablation for Paroxysmal Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) inducibility with burst pacing (BP) after radiofrequency ablation (RFA) has been reported to be associated with AF recurrence. In contrast, the relevance of inducibility and recurrence after cryoablation (CRA) is unclear.

METHODS

We investigated 367 patients undergoing initial ablation for paroxysmal AF (RFA: 174, CRA: 193). Propensity score matching was conducted, retaining 134 patients in each group. Following pulmonary vein isolation (PVI), the inducibility by BP was tested. Inductions at 250 ppm were defined as low-frequency burst pacing (LFBP) positive, and those at 300 ppm were classified as medium-frequency burst pacing (MFBP) positive. They were followed for 600 days.

RESULTS

Forty-eight patients (18%) had AF recurrence. There was no significant difference in the recurrence rate between RFA and CRA (17% vs. 19%, Log-rank p = 0.79). In RFA, significant differences were observed for both LFBP (Log-rank p < 0.001) and MFBP (Log-rank p < 0.001). In contrast, in CRA, there were no significant differences for either LFBP (Log-rank p = 0.39) or MFBP (Log-rank p = 0.19). Multivariable analysis revealed that LFBP-positive (hazards ratio [HR] = 5.75, 95% confidence interval [CI] 2.41-13.7, p < 0.001) was an independent predictor for recurrence with RFA. Acute reconnection (HR = 2.73, 95% CI 1.13-6.56, p = 0.025) was an independent predictor for recurrence with CRA.

CONCLUSION

The inducibility by BP after RFA predicted recurrence at both low and medium frequencies. LFBP-positive was an independent predictor of recurrence in multivariable analysis. In contrast, the inducibility by BP after CRA was not a predictor of recurrence.

TRAIL REGISTRATION

This study did not require clinical trial registration.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

Validation of a prediction model for early reconnection after cryoballoon ablation

BACKGROUND

We previously developed an early reconnection/dormant conduction (ERC) prediction model for cryoballoon ablation to avoid a 30-min waiting period with adenosine infusion. We now aimed to validate this model based on time to isolation, number of unsuccessful cryo-applications, and nadir balloon temperature.

METHODS

Consecutive atrial fibrillation patients who underwent their first cryoballoon ablation in 2018-2019 at the Leiden University Medical Center were included. Model performance at the previous and at a new optimal cutoff value was determined.

RESULTS

A total of 201 patients were included (85.57% paroxysmal AF, 139 male, median age 61 years (IQR 53-69)). ERC was found in 35 of 201 included patients (17.41%) and in 41 of 774 veins (5.30%). In the present study population, the previous cutoff value of - 6.7 provided a sensitivity of 37.84% (previously 70%) and a specificity of 89.07% (previously 86%). Shifting the cutoff value to - 7.2 in both study populations resulted in a sensitivity of 72.50% and 72.97% and a specificity of 78.22% and 78.63% in data from the previous and present study respectively. Negative predictive values were 96.55% and 98.11%. Applying the model on the 101 patients of the present study with all necessary data for all veins resulted in 43 out of 101 patients (43%) not requiring a 30-min waiting period with adenosine testing. Two patients (2%) with ERC would have been missed when applying the model.

CONCLUSIONS

The previously established ERC prediction model performs well, recommending its use for centers routinely using adenosine testing following PVI.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

2023 Cardiac Society of Australia and New Zealand Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation

Catheter ablation for atrial fibrillation (AF) has increased exponentially in many developed countries, including Australia and New Zealand. This Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation from the Cardiac Society of Australia and New Zealand (CSANZ) recognises healthcare factors, expertise and expenditure relevant to the Australian and New Zealand healthcare environments including considerations of potential implications for First Nations Peoples. The statement is cognisant of international advice but tailored to local conditions and populations, and is intended to be used by electrophysiologists, cardiologists and general physicians across all disciplines caring for patients with AF. They are also intended to provide guidance to healthcare facilities seeking to establish or maintain catheter ablation for AF.

Italian Association of Hospital Cardiologists Position Paper 'Gender discrepancy: time to implement gender-based clinical management'

It has been well assessed that women have been widely under-represented in cardiovascular clinical trials. Moreover, a significant discrepancy in pharmacological and interventional strategies has been reported. Therefore, poor outcomes and more significant mortality have been shown in many diseases. Pharmacokinetic and pharmacodynamic differences in drug metabolism have also been described so that effectiveness could be different according to sex. However, awareness about the gender gap remains too scarce. Consequently, gender-specific guidelines are lacking, and the need for a sex-specific approach has become more evident in the last few years. This paper aims to evaluate different therapeutic approaches to managing the most common women's diseases.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Recurrent Atrial Fibrillation Ablation after Initial Successful Pulmonary Vein Isolation

BACKGROUND

Pulmonary vein isolation (PVI) is an effective treatment option for patients with symptomatic atrial fibrillation (AF). However, the electrical recovery of pulmonary veins (PVs) is the main trigger for AF recurrences. This study investigates the characteristics of patients admitted for redo AF ablation, the PV reconnection rates depending on previous ablation modalities and the impact of different ablation strategies for redo procedures.

METHODS

Consecutive patients undergoing first redo AF ablation were included. Patients were grouped according to the electrical recovery of at least one PV. The impacts of the technique for first AF ablation on PV reconnection rates and patients with and without PV reconnection were compared. Different ablation strategies for redo procedures were compared and its recurrence rates after a mean follow-up of 25 ± 20 months were investigated.

RESULTS

A total of 389 patients (68 ± 10 years; 57% male; 39% paroxysmal AF) underwent a first redo. The median time between the first and redo procedure was 40 ± 39 months. Radiofrequency was used in 278 patients, cryoballoon was used in 85 patients and surgical AF ablation was performed on 26 patients. In total, 325 patients (84%) had at least one PV reconnected, and the mean number of reconnected PVs was 2.0 ± 1.3, with significant differences between ablation approaches (p for all = 0.002); this was mainly due to differences in the left inferior PV and right superior PV reconnections. The presence of PV reconnection during redo was not associated with better long-term success compared to completely isolated PVs (67% vs. 67%; log-rank p = 0.997). Overall, the different ablation strategies for redos were comparable regarding AF recurrences during follow-up (p = 0.079), with the ablation approach having no impact in the case of left atrial low voltage or without.

CONCLUSIONS

PV reconnections after initial successful PVI are common among all techniques of AF ablation. Long-term rhythm control off antiarrhythmic drugs was possible in 2/3 of all patients after the redo procedure; however, different ablation strategies with extra-PV trigger ablation did not improve long-term success. Patients with recurrent AF after PVI constitute a challenging group of patients.

Methods and techniques for increasing the safety and efficacy of pulmonary vein isolation in patients with atrial fibrillation

The most common type of sustained arrhythmia is atrial fibrillation (AF). Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation for atrial fibrillation, which has emerged as the primary therapeutic strategy for atrial fibrillation patients. Unfortunately, about one-third of patients experience recurrent atrial arrhythmias after the procedure.

Comparison of pulmonary vein isolation using cryoballoon, high-power short-duration, and conventional radiofrequency ablation for atrial fibrillation: a propensity score-weighted study

Background

The comparative efficacy, saftey, and heart rate variability (HRV) parameters after pulmonary vein isolation using cryoballoon (Cryo-PVI), high-power short-duration (HPSD-PVI), and conventional radiofrequency ablation (conventional-PVI) for atrial fibrillation (AF) is unclear.

Materials and methods

In this propensity score-weighted, retrospective analysis of a single-center cohort, we analyzed 3,395 patients (26.2% female, 74.5% paroxysmal AF) who underwent AF catheter ablation without an empirical left atrial ablation. Procedural factors, recurrence rates, complication rates, and the post-procedural HRV parameters were compared across the Cryo-PVI (n = 625), HPSD-PVI (n = 748), and conventional-PVI (n = 2,022) groups.

Results

Despite the shortest procedural time in the Cryo-PVI group (74 min for Cryo-PVI vs. 104 min for HPSD-PVI vs. 153 min for conventional-PVI, p < 0.001), the major complication (p = 0.906) and clinical recurrence rates were similar across the three ablation groups (weighted log-rank, p = 0.824). However, the Cryo-PVI group was associated with a significantly lower risk of recurrent AF in patients with paroxysmal AF [weighted hazard ratio (WHR) 0.57, 95% confidence interval (CI) 0.37-0.86], whereas it was associated with a higher risk of recurrent AF in patients with persistent AF (WHR 1.41, 95% CI 1.06-1.89, p for interaction of <0.001) compared with the conventional-PVI group. In the subgroup analysis for the HRV, the Cryo-PVI group had the highest low-frequency-to-high-frequency ratio at 1-year post-procedure, whereas the HPSD-PVI group had the lowest low-frequency-to-high-frequency ratio at 1-year post-procedure (p < 0.001).

Conclusions

The Cryo-PVI group had better rhythm outcomes in patients with paroxysmal AF but worse rhythm outcomes in patients with persistent AF and a higher long-term post-procedural sympathetic nervous activity and sympatho-vagal balance compared with the conventional-PVI group.

Safety and efficacy of steerable versus non-steerable sheaths for catheter ablation of atrial fibrillation systematic review and meta-analysis

OBJECTIVES

With the development of radiofrequency (RF) ablation technology. In recent years, more and more patients with atrial fibrillation (AF) have been treated with RF ablation. Steerable sheaths (SS) have been widely used in RF ablation of AF. The aim of this meta-analysis was to compare the efficacy and safety of AF ablation using SS and non-steerable sheaths (NSS).

METHODS

From the beginning to March 2022, we conducted a comprehensive, systematic search of the databases PubMed, MEDLINE, EMBASE, Web of Science and the Cochrane Library to finish the study. For categorical and continuous data, we used ORs and mean difference to calculate the effect. We also estimated the 95% CI.

RESULTS

Five studies of RF ablation of AF were selected, three prospective and two retrospective, involving 282 SS and 236 NSS ablation patients. The rate of recurrence of AF or atrial arrhythmias was 27.3% versus 42.8% (OR: 0.52, 95% CI 0.36, 0.76, z=3.41, p=0.0006) and acute pulmonary vein (PV) reconnection (8.7% vs 17.4%, OR: 0.47, 95% CI 0.23, 0.95, z=2.10, p=0.04). In the SS group and the NSS group, the total ablation time (p=0.25), fluoroscopy time (p=0.26) and total operative time (p=0.35) were not significantly different.

CONCLUSIONS

Compared with the use of NSS, the use of SS for RF ablation of AF can effectively reduce the recurrence rate of AF and the occurrence of acute PVs reconnection events. However, there is no advantage in shortening the total RF time, fluoroscopy time, total surgical time and reducing complications.

Holistic Approaches to Arrhythmia Management: Combining Medication, Ablation, and Device Interventions

This narrative review investigates the severe health issue of arrhythmias, which affects millions of people worldwide. A multifaceted strategy incorporating medicine, catheter ablation, and advanced device interventions is necessary to manage these disorders effectively. Medication is the cornerstone, and as antiarrhythmic medications develop, their efficacy and side effects are reduced. Success depends on having individualized treatment strategies that consider patient profiles and arrhythmia type. Catheter ablation, a minimally invasive surgery that targets and removes faulty heart electrical circuits, has become a potent therapy when drugs are ineffective. Technological developments, including high-resolution mapping systems and customized catheters, improve precision. Pacemakers and implantable cardioverter-defibrillators (ICDs) are two examples of implantable cardiac devices essential to managing all types of arrhythmias. Pacemakers provide a regular heartbeat when the body's natural pacing mechanism fails. At the same time, ICDs, with cutting-edge algorithms, can identify and stop life-threatening arrhythmias and offer high-risk patients vital protection. As device technology advances, smaller, more durable devices become available, improving patient comfort and lowering the need for replacements. The seamless fusion of these three strategies is where holistic arrhythmia management shines. Even for difficult instances, customized combination therapy combining medicine, ablation, and device interventions offers complete solutions. Healthcare providers must collaborate for this integrated strategy to deliver personalized, efficient, and holistic care. In conclusion, the management of arrhythmias has developed into a dynamic, synergistic discipline where drugs, catheter ablation, and devices all work in concert to deliver comprehensive care. For those with arrhythmias, a patient-centered strategy that considers their particular patient features and best integrates different modalities can significantly enhance their quality of life. The effectiveness and accessibility of holistic arrhythmia management could be further improved because of ongoing developments in these fields, which is encouraging for patients and medical professionals.

Ablation of residual potentials along the circumferential line reduces acute pulmonary vein reconnection

INTRODUCTION

Acute pulmonary vein (PV) reconnection is frequently encountered in patients undergoing PV isolation (PVI) procedure for the treatment of atrial fibrillation. In this study, we investigated whether the identification and ablation of residual potentials (RPs), after the initial achievement of PVI, reduces acute PV reconnection rate.

METHODS

Following PVI in 160 patients, mapping along the ablation line was performed to identify RPs, defined as bipolar amplitude ≥0.2 mV or 0.1-0.19 mV combined with a negative component of the unipolar electrogram. Ipsilateral PV sets with RPs were randomized to either no further ablation (Group B) or to additional ablation of the identified RPs (Group C). The primary study endpoint was spontaneous or adenosine-mediated acute PV reconnection after a 30-min waiting period and was also evaluated in ipsilateral PV sets without RPs (Group A).

RESULTS

After isolation of 287 PV pairs, 135 had no RPs (Group A), whereas the remaining PV pairs were randomized to either Group B (n = 75) or Group C (n = 77). Ablation of RPs resulted in a reduction of spontaneous or adenosine-mediated PV reconnection rate (16.9% in Group C vs 48.0% in Group B; p < 0.001). Group A was associated with a significantly lower percentage of acute PV reconnection as compared to Group B (5.9% vs 48.0%; p < 0.001) and Group C (5.9% vs 16.9%; p = 0.016).

CONCLUSION

After PVI achievement, the absence of RPs along the circumferential line is associated with a low likelihood of acute PV reconnection rate. Ablation of RPs significantly reduces spontaneous or adenosine-mediated acute PV reconnection rate.

Ostial vs. wide area circumferential ablation guided by the Ablation Index in paroxysmal atrial fibrillation

AIMS

Pulmonary vein isolation (PVI) guided by the Ablation Index (AI) has shown high acute and mid-term efficacy in the treatment of paroxysmal atrial fibrillation (AF). Previous data before the AI-era had suggested that wide-area circumferential ablation (WACA) was preferable to ostial ablation. However, with the use of AI, we hypothesize that ostial circumferential ablation is non-inferior to WACA and can improve outcomes in paroxysmal AF.

METHODS AND RESULTS

Prospective, multicentre, non-randomized, non-inferiority study of consecutive patients were referred for paroxysmal AF ablation from January 2020 to September 2021. All procedures were performed using the AI software, and patients were separated into two different groups: WACA vs. ostial circumferential ablation. Acute reconnection, procedural data, and 1-year arrhythmia recurrence were assessed. During the enrolment period, 162 patients (64% males, mean age of 60 ± 11 years) fulfilled the study inclusion criteria-81 patients [304 pulmonary vein (PV)] in the WACA group and 81 patients (301 PV) in the ostial group. Acute PV reconnection was identified in 7.9% [95% confidence interval (CI), 4.9-11.1%] of PVs in the WACA group compared with 3.3% (95% CI, 1.8-6.1%) of PVs in the ostial group [P < 0.001 for non-inferiority; adjusted odds ratio 0.51 (95% CI, 0.23-0.83), P = 0.05]. Patients in the WACA group had longer ablation (35 vs. 29 min, P = 0.001) and procedure (121 vs. 102 min, P < 0.001) times. No significant difference in arrhythmia recurrence was seen at 1-year of follow-up [11.1% in WACA vs. 9.9% in ostial, hazard ratio 1.13 (95% CI, 0.44-1.94), P = 0.80 for superiority].

CONCLUSION

In paroxysmal AF patients treated with tailored AI-guided PVI, ostial circumferential ablation is not inferior to WACA with regard to acute PV reconnection, while allowing quicker procedures with less ablation time.

Standard vs Augmented Ablation of Paroxysmal Atrial Fibrillation for Reduction of Atrial Fibrillation Recurrence: The AWARE Randomized Clinical Trial

Importance

Recurrent atrial fibrillation (AF) commonly occurs after catheter ablation and is associated with patient morbidity and health care costs.

Objective

To evaluate the superiority of an augmented double wide-area circumferential ablation (WACA) compared with a standard single WACA in preventing recurrent atrial arrhythmias (AA) (atrial tachycardia, atrial flutter, or atrial fibrillation [AF]) in patients with paroxysmal AF.

Design, Setting, and Participants

This was a pragmatic, multicenter, prospective, randomized, open, blinded end point superiority clinical trial conducted at 10 university-affiliated centers in Canada. The trial enrolled patients 18 years and older with symptomatic paroxysmal AF from March 2015 to May 2017. Analysis took place between January and April 2022. Analyses were intention to treat.

Interventions

Patients were randomized (1:1) to receive radiofrequency catheter ablation for pulmonary vein isolation with either a standard single WACA or an augmented double WACA.

Main Outcomes and Measures

The primary outcome was AA recurrence between 91 and 365 days postablation. Patients underwent 42 days of ambulatory electrocardiography monitoring after ablation. Secondary outcomes included need for repeated catheter ablation and procedural and safety variables.

Results

Of 398 patients, 195 were randomized to the single WACA (control) arm (mean [SD] age, 60.6 [9.3] years; 65 [33.3%] female) and 203 to the double WACA (experimental) arm (mean [SD] age, 61.5 [9.3] years; 66 [32.5%] female). Overall, 52 patients (26.7%) in the single WACA arm and 50 patients (24.6%) in the double WACA arm had recurrent AA at 1 year (relative risk, 0.92; 95% CI, 0.66-1.29; P = .64). Twenty patients (10.3%) in the single WACA arm and 15 patients (7.4%) in the double WACA arm underwent repeated catheter ablation (relative risk, 0.72; 95% CI, 0.38-1.36). Adjudicated serious adverse events occurred in 13 patients (6.7%) in the single WACA arm and 14 patients (6.9%) in the double WACA arm.

Conclusions and Relevance

In this randomized clinical trial of patients with paroxysmal AF, additional ablation by performing a double ablation lesion set did not result in improved freedom from recurrent AA compared with a standard single ablation set.

Trial Registration

ClinicalTrials.gov Identifier: NCT02150902.

High-power short-duration versus low-power long-duration ablation guided by the ablation index

AIMS

To compare the two different ablation strategies, both guided by the Ablation Index (AI), in the setting of atrial fibrillation (AF) ablation: high-power short-duration (HPSD) ablation using 40 W on the posterior wall and 50 W elsewhere versus low-power long-duration (LPLD) using 25 W posteriorly and 35 W elsewhere.

METHODS

Prospective, multicenter nonrandomized, noninferiority study of consecutive patients referred for paroxysmal AF ablation from January 2018 to July 2019. Ablation was guided by the AI (≥500 for anterior segments, ≥450 for the roof and inferior segments and 400 posteriorly) and an interlesion distance (ILD) ≤ 6 mm. Patients were separated into two groups: HPSD vs LPLD. Acute reconnection (after adenosine trial) and 2-year outcomes were assessed.

RESULTS

160 patients (61% males, median age of 62 [IQR 51-69] years), fulfilled the study inclusion criteria - 80 patients (316 pulmonary veins [PV]) in the HPSD group and 80 patients (314 PV) in the LPLD. The probability of acute PV reconnection was similar between both groups: 2.2% in HPSD, 95%CI 0.6% to 3.8% vs. 3.4% in LPLD, 95%CI 1.4% to 5.4%; p < 0.001 for noninferiority. Median PV ablation time (20 min vs 30 min, p < 0.01) and procedure duration (80 min vs 100 min, p < 0.001) were shorter in the HPSD group. After a median follow-up of 26 months, arrhythmia recurrence was similar between groups (17.5% in HPSD group vs. 18.8% in LPLD group, p = 0.79).

CONCLUSIONS

In paroxysmal AF patients treated with the Ablation Index, a HPSD strategy is noninferior to the more standard LPLD ablation, while allowing for quicker procedures with shorter ablation times.

Characterization of high-power and very-high-power short-duration radiofrequency lesions performed with a new-generation catheter and a temperature-control ablation mode

INTRODUCTION

High-power short-duration (HPSD) has been proposed to shorten procedure times while maintaining efficacy and safety. We evaluated the differences in size and geometry between radiofrequency lesions obtained with this method and conventional ones.

METHODS AND RESULTS

Twenty-eight sets of 10 perpendicular radiofrequency applications were performed with two commercially available catheters: a temperature-controlled HPSD catheter (QDot-Micro) and a conventional power-controlled catheter (Thermocool SmartTouch) on porcine left ventricle. Different power settings (35, 40, 50, and 90 W), contact force (CF; 10 and 20 g), ablation index (AI; 400 and 550), and application times were combined to create conventional (35-40 W), HPSD (50 W) and very-high-power short-duration (VHPSD; 90 W) lesions, that were cross-sectioned and measured. About 4-s VHPSD lesions were smaller, shallower, and thinner than HPSD performed with the QDot-Micro catheter in any scenario of CF or AI (61 ± 7.8 mm³ , 6.1 ± 0.3 mm wide, and 2.9 ± 0.1 mm deep with 10 g; 72.2 ± 0.5 mm³ , 6.8 ± 0.3 mm wide, and 2.9 ± 0.2 mm deep with 20 g). Conventional and HPSD lesions performed with the temperature-controlled catheter were generally bigger, deeper, and wider than the ones obtained with the power-controlled catheter, as well as more consistent in size. This was especially true with the lower CF and AI scenario, while differences were less notable with other setting combinations.

CONCLUSION

VHPSD lesions performed with QDot-Micro catheter were smaller than any other lesions, which is especially attractive for posterior left atrial wall ablation. On the contrary, conventional-powered and HPSD lesions performed with this catheter were equally sized (or even bigger with lower CF and AI objectives), as well as more consistent in size, which would guarantee transmurality in other locations.

Temperature-controlled high-power short-duration ablation with 90 W for 4 s: outcome, safety, biophysical characteristics and cranial MRI findings in patients undergoing pulmonary vein isolation

BACKGROUND

High-power short-duration (HPSD) radiofrequency ablation (RFA) is highly efficient and safe while reducing procedure and RF time in pulmonary vein isolation (PVI). The QDot™ catheter is a novel contact force ablation catheter that allows automated flow and power adjustments depending on the local tissue temperature to maintain a target temperature during 90 W/4 s lesions. We analysed intraprocedural data and periprocedural safety using the QDot-catheter in patients undergoing PVI for paroxysmal atrial fibrillation (PAF).

METHODS

We included n = 48 patients undergoing PVI with the QDot-catheter with a temperature-controlled HPSD ablation mode with 90 W/4 s (TC-HPSD). If focal reconnection occurred besides repeat ablation, the ablation mode was changed to 50 W/15 s (QMode). N = 23 patients underwent cerebral MRI to detect silent cerebral lesions.

RESULTS

Mean RF time was 8.1 ± 2.8 min, and procedure duration was 84.5 ± 30 min. The overall maximal measured catheter tip temperature was 52.0 °C ± 4.6 °C, mean overall applied current was 871 mA ± 44 mA and overall applied energy was 316 J ± 47 J. The mean local impedance drop was 12.1 ± 2.4 Ohms. During adenosine challenge, n = 14 (29%) patients showed dormant conduction. A total of n = 24 steam pops were detected in n = 18 patients (39.1%), while no pericardial tamponade occurred. No periprocedural thromboembolic complications occurred, while n = 4 patients (17.4%) showed silent cerebral lesion.

CONCLUSIONS

TC-HPSD ablation with 90 W/4 s using the QDot-catheter led to a reduction of procedure and RF time, while no major complications occurred. Despite optimized temperature control and power adjustment, steam pops occurred in a rather high number of patients, while none of them leads to tamponade or to clinical or neurological deficits.

PolarX Cryoballoon metrics predicting successful pulmonary vein isolation: targets for ablation of atrial fibrillation

AIM

Evaluate the novel PolarX Cryoballoon in atrial fibrillation (AF) catheter ablation through a propensity-matched comparison with the Arctic Front Advance (AFA). The aim was also to identify cryoablation metrics that are predictive of successful pulmonary vein isolation (PVI) with the PolarX Cryoballoon.

METHODS AND RESULTS

This prospective multi-centre study included patients that underwent cryoablation for AF. All patients underwent PVI with reconnection assessed after a 30-min waiting period and adenosine. Safety, efficacy, and cryoablation metrics were compared between PolarX and a propensity-matched AFA cohort. Seventy patients were included with 278 veins treated. In total, 359 cryoablations were performed (1.3 ± 0.6 per vein) to achieve initial PVI with 205 (73.7%) veins isolating with a single cryoablation. Independent predictors for achieving initial PVI included temperature at 30 s [odds ratio (OR) 1.26; P = 0.003] and time to reach -40°C (OR 1.88; P < 0.001) with an optimal cut-off of ≤-38.5°C at 30 s [area under the curve (AUC) 0.79; P < 0.001] and ≤-40°C at ≤32.5 s (AUC 0.77; P < 0.001), respectively. Of the 278 veins, 46 (16.5%) veins showed acute reconnection. Temperature at 30 s (≤-39.5°C, OR 1.24; P = 0.002), nadir temperature (≤-53.5°C, OR 1.35; P = 0.003), and time to isolation (≤38.0 s, OR 1.18; P = 0.009) were independent predictors of sustained PVI. Combining two of these three targets was associated with reconnection in only 2-5% of PVs. Efficacy and safety of the PolarX Cryoballoon were comparable to AFA Cryoballoon, however, cryoablation metrics were significantly different.

CONCLUSIONS

The PolarX Cryoballoon has a different cryoablation profile to AFA Cryoballoon. Prospective testing of these proposed targets in large outcomes studies is required.

Augmented wide area circumferential catheter ablation for reduction of atrial fibrillation recurrence (AWARE) trial: Design and rationale

BACKGROUND

Recurrence of atrial fibrillation (AF) after a pulmonary vein isolation procedure is often due to electrical reconnection of the pulmonary veins. Repeat ablation procedures may improve freedom from AF but are associated with increased risks and health care costs. A novel ablation strategy in which patients receive "augmented" ablation lesions has the potential to reduce the risk of AF recurrence.

OBJECTIVE

The Augmented Wide Area Circumferential Catheter Ablation for Reduction of Atrial Fibrillation Recurrence (AWARE) Trial was designed to evaluate whether an augmented wide-area circumferential antral (WACA) ablation strategy will result in fewer atrial arrhythmia recurrences in patients with symptomatic paroxysmal AF, compared with a conventional WACA strategy.

METHODS/DESIGN

The AWARE trial was a multicenter, prospective, randomized, open, blinded endpoint trial that has completed recruitment (ClinicalTrials.gov NCT02150902). Patients were randomly assigned (1:1) to either the control arm (single WACAlesion set) or the interventional arm (augmented- double WACA lesion set performed after the initial WACA). The primary outcome was atrial tachyarrhythmia (AA; atrial tachycardia [AT], atrial flutter [AFl] or AF) recurrence between days 91 and 365 post catheter ablation. Patient follow-up included 14-day continuous ambulatory ECG monitoring at 3, 6, and 12 months after catheter ablation. Three questionnaires were administered during the trial- the EuroQuol-5D (EQ-5D) quality of life scale, the Canadian Cardiovascular Society Severity of Atrial Fibrillation scale, and a patient satisfaction scale.

DISCUSSION

The AWARE trial was designed to evaluate whether a novel approach to catheter ablation reduced the risk of AA recurrence in patients with symptomatic paroxysmal AF.

Two years after pulmonary vein isolation guided by ablation index-a multicenter study

Background

The use of the Ablation Index (AI) software for paroxysmal atrial fibrillation (AF) has been associated with higher acute effectiveness and higher 1-year arrhythmia freedom. There is, however, a lack of data concerning longer follow-up. We aim to evaluate the 2-year outcomes after a standardized AI-guided pulmonary vein isolation (PVI).

Methods

Prospective, multicenter study of consecutive patients referred for paroxysmal AF ablation from January 2018 to July 2019. PVI was guided by a tailored AI value (≥500 for anterior segment, ≥450 for the roof segments and inferior segments, and 400 for the posterior wall) and an ILD ≤6 mm. The primary endpoints were acute and long-term effectiveness.

Results

The study included 218 (842 PV) patients (61% males, median age of 60 [IQR 49-68] years) with paroxysmal AF. First-pass isolation was obtained in 93% of the patients, with an acute reconnection occurring in 10.6% of the patients (3.2% of the PV) following adenosine trial. After a median follow-up of 26 (IQR 20-30) months, freedom from any documented atrial arrhythmia was 83.4%, off-AAD. The rate of adverse events was 1.4%. Although procedural parameters differ across centers (p < 0.001), the acute (p = 0.56) and long-term effectiveness (p = 0.83) were consistent between centers.

Conclusions

Patients with paroxysmal AF submitted to an AI-guided PVI workflow presented high arrhythmia freedom at 2-years of follow-up.

Assessment of the Need of a Waiting Period after Pulmonary Vein Isolation with the Ablation Index Software

PURPOSE

Since the widespread availability of contact-force sensing catheters, the need of a waiting period after pulmonary vein isolation (PVI) has not been reassessed. We aim to evaluate whether a waiting period is still necessary after PVI guided by the Ablation Index (AI).

METHODS

Prospective, multicenter, randomized study of consecutive patients referred for paroxysmal atrial fibrillation (AF) ablation from May 2019 to February 2020. Patients were randomized in a 1:1 ratio to PVI with versus without a waiting period of 20 minutes. Acute pulmonary vein (PV) reconnection after adenosine challenge was the primary endpoint. A per-protocol analysis was designed to determine whether a strategy of dismissing the waiting period after PVI was noninferior to waiting 20minutes for identifying acute PV reconnection. PVI was guided by tailored AI values and an inter-lesion distance ≤6mm.

RESULTS

During the enrollment period, 167 patients (56% males, mean age of 57±14 years) fulfilled the study inclusion criteria - 84 patients (308 PV) in the waiting period group (group A) and 83 patients (314 PV) in the group without a waiting period (group B). Acute PV reconnection was identified in 3.8% (95% CI, 1.7% to 5.9%) of PVs in the study group B compared to 2.9% (95% CI, 1.0% to 4.8%) of PVs in the group A (p=0.002 for non-inferiority). At 1-year follow-up there was no significant difference in arrhythmia recurrence between groups (9.5% in group A vs. 9.6% in group B, HR 1.03 [95% CI, 0.39-2.73], p=0.98).

CONCLUSIONS

In paroxysmal AF patients submitted to ablation, a tailored PVI guided by the Ablation Index rendered a 20-minute waiting period unnecessary. This article is protected by copyright. All rights reserved.

Targeted ablation of residual pulmonary vein potentials in atrial fibrillation ablation through ultra-high-density mapping: insights from the CHARISMA registry

INTRODUCTION

Low-voltage activity beyond pulmonary veins (PVs) may contribute to the failure of ablation of atrial fibrillation (AF) in the long term. We aimed to assess the presence of gaps (PVG) and residual potential (RAP) within the antral scar by means of an ultra-high density mapping (UHDM) system.

METHODS

We studied consecutive patients from the CHARISMA registry who were undergoing AF ablation and had complete characterization of residual PV antral activity. The Lumipoint^TM (Boston Scientific) map-analysis tool was used sequentially on each PV component. The ablation endpoint was PV isolation (PVI) and electrical quiescence in the antral region.

RESULTS

Fifty-eight cases of AF ablation were analyzed. A total of 86 PVGs in 34 (58.6%) patients and 44 RAPs in 34 patients (58.6%) were found. In 16 (27.6%) cases, we found at least one RAP in patients with complete absence of PV conduction. RAPs showed a lower mean voltage than PVG (0.3±0.2mV vs 0.7±0.5mV, p<0.0001), whereas the mean number of EGM peaks was higher (8.4±1.4 vs 3.2±1.5, p<0.0001). The percentage of patients in whom RAPs were detected through Lumipoint^TM was higher than through propagation map analysis (58.6% vs 36.2%, p=0.025). Acute procedural success was 100%, with all PVs successfully isolated and RAPs completely abolished in all study patients. During a mean follow-up of 453±133 days, 6 patients (10.3%) suffered an AF/AT recurrence.

CONCLUSION

Local vulnerabilities in antral lesion sets were easily discernible by means of the UHDM system in both de novo and redo patients when no PV conduction was present.

CLINICAL TRIAL REGISTRATION

Catheter Ablation of Arrhythmias with a High-Density Mapping System in Real-World Practice (CHARISMA). URL: http://clinicaltrials.gov/Identifier: NCT03793998 This article is protected by copyright. All rights reserved.

Efficacy and safety of high-power short duration atrial fibrillation ablation in elderly patients

INTRODUCTION

Data about atrial fibrillation (AF) ablation using high-power short duration (HPSD) radiofrequency ablation in the elderly population is still scarce. The aim of our study was to investigate the efficacy and safety of HPSD ablation in patients over 75 years compared to younger patients.

METHODS

Consecutive patients older than 75 years with paroxysmal or persistent AF undergoing a first-time AF ablation using 50 W HPSD ablation approach were analyzed in this retrospective observational analysis and compared to a control group <75 years. Short-term endpoints included intraprocedural reconnection of at least one pulmonary vein (PV) and intrahospital and AF recurrence during 3 months blanking period, as well as a long-term endpoint of freedom from atrial arrhythmias of antiarrhythmic drugs after 12 months.

RESULTS

A total of 540 patients underwent a first AF ablation with HPSD (66 ± 10 years; 58% male; 47% paroxysmal AF). Mean age was 78 ± 2.4 and 63 ± 6.3 years (p < .001), respectively. Elderly patients were significantly more often women (p < .001). The procedure, fluoroscopy, and ablation were comparable. Elderly patients revealed significantly more often extra-PV low-voltage areas requiring additional left atrial ablations (p < .001). Overall complication rates were low; however, elderly patients revealed higher major complication rates mainly due to unmasking sick sinus syndrome (p = .003). Freedom from arrhythmia recurrences was comparable (68% vs. 76%, log-rank p = .087). Only in the subgroup of paroxysmal AF, AF recurrences were more common after 12 months (69% vs. 82%; log-rank p = .040; hazard ratio: 1.462, p = .044) in the elderly patients. In multivariable Cox regression analysis of the whole cohort persistent AF, female gender, diabetes mellitus and presence of left atrium low-voltage areas, but not age >75 years were associated with AF recurrences.

CONCLUSION

HPSD AF ablation of patients >75 years in experienced centers is safe and effective. Therefore, age alone should not be the reason to withhold AF ablation from vital elderly patients due to only a slightly worse outcome and safety profile. In paroxysmal AF, elderly patients have more recurrences compared to the younger control group.

Meta-analysis of high power short duration in atrial fibrillation ablation - a superior efficient ablation strategy

BACKGROUND

The high power short duration (HPSD) approach was hoped to further improve the efficacy and safety in radiofrequency ablation of atrial fibrillation (AF), compared with Low power long duration (LPLD). However, the conclusion was controversial based on the previous limited data. The aim of this meta-analysis was to evaluate whether the clinical benefits of HPSD are superior to that of LPLD.

METHODS

The PubMed, OVID, the Cochrane Library, and Elsevier's ScienceDirect databases were searched for clinical studies to compare HPSD and LPLD approach by simple search strings benefiting to a wider screened scope.

RESULTS

Fifteen trials with 3255 patients were included in this analysis. Pooled analyses suggested that HPSD was associated with a lower recurrence of atrial tachyarrhythmias (ATAs) at 1-year follow-up (OR: 0.49; 95% CI: 0.35 to 0.67, p < .0001), benefitted from AF recurrence reduced (OR: 0.46; 95% CI: 0.31 to 0.67, p < .0001), rather than atrial tachycardia/atrial flutter (AT/AFL), but similar at 6 months follow-up, with a decreased oesophageal thermal injury (ETI) (OR: 0.48; 95% CI: 0.30 to 0.77, p = .002). Meanwhile, the HPSD approach benefitted to increase first-pass pulmonary vein isolation (FPI) (OR: 0.47; 95% CI: 0.34 to 0.64, p < .00001) and decrease acute pulmonary vein re-isolation (PVR) (OR: 0.45; 95% CI: 0.35 to 0.58, p < .00001), both mainly embodied in left pulmonary veins (PVs). HPSD showed a decreased procedural time (SMD: -0.95; 95% CI: -1.06 to -0.85, p < .00001), ablation number for pulmonary vein isolation (PVI) (SMD: -0.41; 95% CI: -0.58 to -0.24, p < .00001) and fluoroscopy time (SMD: -0.22; 95% CI: -0.32 to -0.12, p < .0001), which benefits from PVI + additional ablation strategy (SMD: -0.33; 95% CI: -0.46 to -0.21, p < .0001).

CONCLUSIONS

The HPSD approach was associated with decreasing post-ablation AF recurrence in the 1-year follow-up, ETI, acute PVR (increasing FPI correspondingly), procedural time, ablation number for PVI and fluoroscopy time, benefitted to improve clinical outcomes and procedural process with improved safety.

Outcome of High-power Short-duration Radiofrequency Ablation in Combination with Half-Normal Saline Irrigation for the Treatment of Atrial Fibrillation

BACKGROUND

Data regarding the use of high-power short-duration (HPSD) radiofrequency (RF) in combination with half-normal saline irrigation for catheter irrigation is limited.

OBJECTIVES

This study investigated the safety and efficacy of using HPSD RF ablation in combination with half-normal saline irrigation for the treatment of AF.

METHODS

 One hundred consecutive patients with AF underwent RF ablation using HPSD combined with half-normal saline for catheter irrigation. In addition, the following ablation strategies were used: 1 mm tags for the display of ablation lesions on the mapping system, high-frequency jet ventilation (HFJV), low contact force, pacing after ablation to verify areas of noncapture, atrial/ventricular pacing at 500 to 700 ms to aid in catheter stability, use of two skin electrodes to reduce impedance, and post-ablation adenosine infusion. Power was started at 40-45 W and was modulated manually based on impedance changes.

RESULTS

 The average age of patients was 65.2 years and 70% were male. Forty-seven percent had paroxysmal AF and the average CHA₂ DS₂ -VASc score was 2.1±1.6. The average power and lesion duration were 38.1 ± 3.3 W and 8.1 ± 2.3 seconds, respectively. During a median follow-up period of 321 ± 139 days, 89% of the patients remained free from any atrial arrhythmias after a single RF ablation procedure. No procedure-related death, stroke, pericardial effusion, or atrioesophageal fistula occurred during follow-up.

CONCLUSIONS

 Catheter ablation using HPSD RF lesions in combination with half-normal saline irrigation and is safe and effective, and results in high rate of freedom from AF. This article is protected by copyright. All rights reserved.

Catheter ablation of atrial fibrillation in Korea: results from the Korean Heart Rhythm Society Ablation Registry for Atrial Fibrillation (KARA)

Background

This study aims to investigate the current status of AF (atrial fibrillation) catheter ablation in Korea.

Methods

The patients who underwent AF catheter ablation from September 2017 to December 2019 were prospectively enrolled from 37 arrhythmia centers. Demographic data, procedural characteristics, the extent of catheter ablation, acute success of the ablation lesion set, rate and independent risk factor for recurrence of AF were analyzed.

Results

A total of 2402 AF patients [paroxysmal AF (PAF) 45.7%, persistent AF (PeAF) 43.1% and redo AF 11.2%] were included. Pulmonary vein isolation (PVI) was performed in 2378 patients (99%) and acute success rate was 97.9%. Additional non-PV ablation (NPVA) were performed in 1648 patients (68.6%). Post-procedural complication rate was 2.2%. One-year AF-free survival rate was 78.6% and the PeAF patients showed poorer survival rate than the ones with other types (PeAF 72.4%, PAF 84.2%, redo AF 80.0%). Additional NPVA did not influence the recurrence of AF in the PAF patients (PVI 17.0% vs. NPVA 14.6%, P value 0.302). However, it showed lower AF recurrence rate in the PeAF patients (PVI 34.9% vs. NPVA 24.4%, P value 0.001). Valvular heart disease, left atrial diameter, PeAF, PVI alone, need of NPVA for terminating AF, and failed ablation were independent predictors of AF recurrence.

Conclusions

Additional NPVA was associated better rhythm outcome in the patients with PeAF, not in the ones with PAF. The independent risk factors for AF recurrence in Korean population were similar to previous studies. Further research is needed to discover optimal AF ablation strategy.

Left atrial wall thickness and its relationship with reconnection after pulmonary vein isolation in patients with atrial fibrillation evaluated using a three-dimensional wall thickness map

Background

The major cause of recurrence after pulmonary vein (PV) isolation for atrial fibrillation (AF) is PV reconnection, and thicker wall could be associated with reconnection.

Objectives

This study aimed to evaluate the wall thickness of the PV antrum in reconnection sites using a three-dimensional (3D) wall thickness map.

Methods

A total of 91 patients who underwent a second ablation procedure due to AF recurrence were evaluated. The locations of the PV reconnection sites were confirmed in electroanatomical maps. A 3D atrial wall thickness (AWT) map was created using computed tomography scan data. The AWT values of the ablation lines of the index procedure were graded in each segment of the PV antrum: grade 1, 0.5 < AWT ≤ 1.0 mm; grade 2, 1.0 < AWT ≤ 1.5 mm; grade 3, 1.5 < AWT ≤ 2.0 mm; grade 4, 2.0 < AWT ≤ 2.5 mm; grade 5, AWT > 2.5 mm.

Results

A total of 281 PV reconnection sites among 1256 segments of the PV antrum in 79 patients were detected. The average AWT grades were 2.7 ± 1.0 and 2.2 ± 1.0 in the reconnected and non-reconnected segments, respectively (P < 0.01). Higher AWT grades were observed in the reconnected superior segments of the left superior PV, carina and inferior segments of the left inferior PV, superior and posterior segments of the right superior PV, and posterior and inferior segments of the right inferior PV.

Conclusion

The reconnected segments of the PV antrum showed thicker myocardium than the non-reconnected ones in patients with recurrent AF after catheter ablation. A wall thickness map for PV isolation could be considered for customized ablation in order to reduce PV reconnection.

A novel approach for effective superior vena cava isolation using the CARTO electroanatomical mapping system

BACKGROUND

Previous studies have demonstrated that some patients have spontaneous right atrium (RA)-superior vena cava (SVC) conduction block, which could be utilized to isolate the SVC effectively by using the Rhythmia mapping system (Boston Scientific). However, employing this approach for SVC isolation using the CARTO electroanatomical mapping system (Biosense Webster) has not yet been clarified. This study aimed to evaluate the safety and efficacy of SVC isolation using the extended early meets late (EEML) tool with the CARTO system.

METHODS

The patients who underwent SVC isolation using the CARTO system were enrolled in this study. The RA-SVC conduction block was visualized with an EEML tool. We prospectively assessed the safety and efficacy of SVC isolation using this system.

RESULTS

We analyzed 54 patients, and all SVCs were successfully isolated with no complications. Altogether, 44 patients (81.5%) had spontaneous RA-SVC conduction block, and the remaining 10 patients (18.5%) did not. The block group required fewer radiofrequency deliveries for the SVC isolation than the nonblock group (10.7 ± 5.0 vs 15.5 ± 4.8, P = .009). The size of the isolated area in the block group was larger than that in the nonblock group (15.2 ± 5.1 cm2 vs 12.4 ± 2.5 cm2, P = .017).

CONCLUSIONS

Approximately 80% of the patients in this study developed a spontaneous RA-SVC conduction block, which might contribute to shortening the time of ablation and avoiding complications.

Left Atrial Reverse Remodeling Following the Modified Box Isolation with Centerline in Patients with Persistent Atrial Fibrillation

Esophageal injury is a rare but serious complication of atrial fibrillation (AF) ablation. To minimize esophageal injury, our persistent AF (PerAF) protocol involves complete left atrial posterior wall (LAPW) and pulmonary vein (PV) isolation (box isolation), with a centerline away from the esophagus. However, there has been a concern that extensive LA isolation might deteriorate LA function. There has been a paucity of data on LA remodeling after box isolation. Therefore, we compared LA size pre- and post-box isolation with an LAPW centerline in patients with PerAF.Patients who underwent catheter ablation (CA) for PerAF between November 2016 and December 2018 were retrospectively evaluated.The LAPW, including all PVs, was completely isolated in 105 consecutive patients (75 men; mean age: 68 ± 10 years) with PerAF, including 58 patients with long-standing PerAF. During a follow-up of 660 ± 332 days, 76 patients (72%) were arrhythmia-free. The LA dimension (38 ± 6 mm versus 42 ± 7 mm; P < 0.0001) and volume index (38 ± 13 mL/m² versus 47 ± 14 mL/m²; P < 0.0001) at 6 months post-ablation were significantly decreased in patients who maintained sinus rhythm compared to pre-ablation. In patients with recurrent AF/atrial tachycardia (AT), these parameters were also significantly decreased (P < 0.001, respectively).Box isolation with a posterior centerline has no esophageal complications and a high clinical success rate in patients with PerAF. Reverse remodeling could be achieved even when using extensive isolation of the PV and LAPW in patients with PerAF.

[Pulmonary vein isolation using radiofrequency ablation]

Catheter ablation represents the primary treatment for most arrhythmias. The effectiveness of catheter ablation for the treatment of atrial fibrillation is superior to drug therapy. Therefore, catheter ablation has been established as an increasingly common procedure in clinical routine. In this context, the electrical isolation of the pulmonary veins (PVI) constitutes the cornerstone of the interventional therapy of paroxysmal and persistent atrial fibrillation. This article describes the procedure of pulmonary vein isolation utilizing radiofrequency point-by-point ablation. It shall be a practical guide for the staff in the electrophysiological laboratory. This article continues a series of manuscripts focusing on interventional electrophysiology topics in the course of EP (electrophysiology) training.This article describes the procedure of pulmonary vein isolation utilizing radiofrequency point-by-point ablation. It shall be a practical guide for the staff in the electrophysiological laboratory. This article continues a series of manuscripts dealing with topics of interventional electrophysiology in the course of EP training.

Predicting early reconnection after cryoballoon ablation with procedural and biophysical parameters

BACKGROUND

Predicting early reconnection/dormant conduction (ERC) immediately after pulmonary vein isolation (PVI) can avoid a waiting period with adenosine testing.

OBJECTIVE

To identify procedural and biophysical parameters predicting ERC.

METHODS

Consecutive atrial fibrillation (AF) patients undergoing a first cryoballoon ablation (Arctic Front Advance) between 2014 and 2017 were included. ERC was defined as manifest or dormant pulmonary vein (PV) reconnection with adenosine 30 minutes after PVI. Time to isolation (TTI), balloon temperatures (BT), and thawing times were evaluated as potential predictors for ERC. Based on a multivariable model, cut-off-values were defined and a formula was constructed to be used in clinical practice.

RESULTS

A total of 136 patients (60 ± 10 years, 96 male, 95% paroxysmal AF) were included. ERC was found in 40 (29%) patients (ERC group) and in 53 of 575 (9%) veins. Procedural and total ablation time and the number of unsuccessful freezes were significantly longer/higher in the ERC group compared to the non-ERC group (150 ± 40 vs 125 ± 34 minutes; 24 ± 5 vs 17 ± 4 minutes, and 38% vs 24%, respectively (P = .028). Multivariable analysis showed that a higher nadir balloon temperature (hazard ratio [HR] 1.17 [1.09-1.23, P < .001), a higher number of unsuccessful freezes (HR 1.69 [1.15-2.49], P = .008) and a longer TTI (HR 1.02 [1.01-1.03], P < .001) were independently associated with ERC, leading to the following formula: 0.02 × TTI + 0.5 × number of unsuccessful freezes + 0.2 × nadir BT with a cut-off value of ≤-6.7 to refrain from a waiting period with adenosine testing.

CONCLUSION

Three easily available parameters were associated with ERC. Using these parameters during ablation can help to avoid a 30-minute waiting period and adenosine testing.

WD, Serpa R. Initial Experience and Results of Combined Treatment for Atrial Fibrillation: Catheter Ablation with High-Power Short Duration Ablation and Left Atrial Appendage Closure

Introduction: Long-term freedom from atrial fibrillation (AF) after catheter ablation and, consequently, the potential for stroke reduction remain unpredictable. Recently, left atrial appendage closure (LAAC) became an effective mechanical alternative to oral anticoagulation (OAC) for stroke prevention in AF patients. Objective: This study aims to evaluate the feasibility and safety of combined treatment for AF with catheter ablation (CA) with the high-power short duration technique associated with LAAC in one single procedure. Methods: Patients with non-valvular AF who underwent combined CA and LAAC procedure were included in the retrospective observational study. Between April 2018 and October 2020, 13 patients with AF were included, eight (61,54%) males, eight (61.54%) with persistent AF (PersAF), mean age 68.54 (65–84) years old, mean time from AF diagnosis to treatment 13.08 (3–33) months, mean CHA2VASC2 5.08 (3–7), all patients with coronary or vascular disease, 12 (92.31%) with hypertension, five (38.46%) with left ventricular dysfunction, four (30.77%) prior strokes using OAC and four (30.77%) patients with diabetes. Indications for LAAC included history of contraindication to OAC because of severe bleeding in eight (61.54%), previous stroke in four (30.77%) and two (13.08%) patients with LAA thrombus, despite the use of two different OAC (one associated with bleeding). One patient had a pseudoaneurysm in femoral artery, and two patients died of non-procedure complications after 30 days. At six months, angiotomography showed successful complete sealing of the LAA in seven (77.72%) of nine patients evaluated, and the two patients without it had a leak of less than 2 mm. After mean follow-up of 14 months (five to 33), 10 (90.91%) of the 11 patients were in sinus rhythm. Three (27.27%) patients, one in blanking period, recovered sinus rhythm after amiodarone. No cardioembolic or bleeding events occurred. Conclusion: In this small observational study, we showed the feasibility and safety of the combined therapy with AF catheter ablation with LAAC with a high rate of sinus rhythm and no cardioembolic event.

Radiofrequency Versus Cryoballoon Catheter Ablation for Paroxysmal Atrial Fibrillation: Durability of Pulmonary Vein Isolation and Effect on Atrial Fibrillation Burden: The RACE-AF Randomized Controlled Trial

Supplemental Digital Content is available in the text.

Background:

Recurrent paroxysmal atrial fibrillation (AF) after catheter ablation is presumably caused by failure to achieve durable pulmonary vein isolation (PVI). The primary methods of PVI are radiofrequency catheter ablation (RF) and cryoballoon catheter ablation (CRYO), but these methods have not been directly compared with respect to PVI durability and the effect thereof on AF burden (% of time in AF).

Methods:

Accordingly, we performed a randomized trial including 98 patients (68% male, 61 [55–67] years) with paroxysmal AF assigned 1:1 to PVI by contact-force sensing, irrigated radiofrequency catheter, or second-generation cryoballoon catheter. Implantable cardiac monitors were inserted ≥1 month before PVI for assessment of AF burden and recurrence, and all patients, irrespective of AF recurrence, underwent a second procedure 4 to 6 months after PVI to determine PVI durability.

Results:

In the second procedure, 152 out of 199 (76%) pulmonary veins (PVs) were found durably isolated after RF and 161 out of 200 (81%) after CRYO (P=0.32), corresponding to durable isolation of all veins in 47% of patients in both groups (P=1.0). Median AF burden before PVI was 5.4% (interquartile range, 0.5%–13.0%) versus 4.0% (0.6%–18.1%), RF versus CRYO (P=0.71), and reduced to 0.0% (0.0%–0.1%) and 0.0% (0.0%–0.5%), respectively (P=0.58)—a reduction of 99.9% (92.9%–100.0%) and 99.3% (85.9%–100.0%; P=0.36). AF burden after PVI significantly correlated to the number of durably isolated PVs (P<0.01), but 9 out of 45 (20%) patients with durable isolation of all veins had recurrence of AF within 4 to 6 months after PVI (excluding a 3-month blanking period).

Conclusions:

PVI by RF and CRYO produce similar moderate to high PVI durability. Both treatments lead to marked reductions in AF burden, which is related to the number of durably isolated PVs. However, for one-fifth of paroxysmal AF patients, complete and durable PVI was not sufficient to prevent even short-term AF recurrence.

Registration:

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03805555.

Impact of adenosine on mechanisms sustaining persistent atrial fibrillation: Analysis of contact electrograms and non-invasive ECGI mapping data

BACKGROUND

We evaluated the effect of adenosine upon mechanisms sustaining persistent AF through analysis of contact electrograms and ECGI mapping.

METHODS

Persistent AF patients undergoing catheter ablation were included. ECGI maps and cycle length (CL) measurements were recorded in the left and right atrial appendages and repeated following boluses of 18 mg of intravenous adenosine. Potential drivers (PDs) were defined as focal or rotational activations completing ≥ 1.5 revolutions. Distribution of PDs was assessed using an 18 segment biatrial model.

RESULTS

46 patients were enrolled. Mean age was 63.4 ± 9.8 years with 33 (72%) being male. There was no significant difference in the number of PDs recorded at baseline compared to adenosine (42.1 ± 15.2 vs 40.4 ± 13.0; p = 0.417), nor in the number of segments harbouring PDs, (13 (11-14) vs 12 (10-14); p = 0.169). There was a significantly higher percentage of PDs that were focal in the adenosine maps (36.2 ± 15.2 vs 32.2 ± 14.4; p < 0.001). There was a significant shortening of CL in the adenosine maps compared to baseline which was more marked in the right atrium than left atrium (176.7 ± 34.7 vs 149.9 ± 27.7 ms; p < 0.001 and 165.6 ± 31.7 vs 148.3 ± 28.4 ms; p = 0.003).

CONCLUSION

Adenosine led to a small but significant shortening of CL which was more marked in the right than left atrium and may relate to shortening of refractory periods rather than an increase in driver burden or distribution. Registered on Clinicaltrials.gov: NCT03394404.

Inducibility of atrial fibrillation after catheter ablation predicts recurrences of atrial fibrillation: a meta-analysis

BACKGROUND

Pulmonary vein isolation (PVI) is a component of standard care for patients with symptomatic atrial fibrillation (AF). Procedural inducibility of AF following PVI has been suggested as predictor of AF recurrence but is discussed controversially. This meta-analysis aimed at evaluating the relevance of electrophysiological inducibility of AF following PVI for future AF recurrences.

METHODS

A literature search of MEDLINE and Web of Science was performed until April 2020. Prospective trials of PVI in patients with AF and post-procedural atrial stimulation to test for inducibility of AF as well as adequate follow-up for AF recurrence (defined as AF >10 s to >10 min at follow-up) were included. Odds ratios (ORs) were analyzed using random-effects models.

RESULTS

A total of 11 trials with 1544 patients (follow-up 7-39 months, age 56 ± 6 years, predominantly male 74 ± 6%) were included. Inducibility of AF post-PVI was predictive for AF recurrence during follow-up (OR 2.08; 95% CI 1.25 to 3.46). Prediction for AF recurrence at follow-up was better for patients with paroxysmal AF (OR 4.06; 95% CI 1.39 to 11.91), stimulation in the CS (OR 2.82, 95% CI 1.17 to 6.79). A trend towards higher ORs was seen without the use of isoproterenol (OR 2.43; 95% CI 1.17 to 5.07), as well as few stimulations during induction and a short definition of AF in meta-regression analyses.

CONCLUSIONS

Electrophysiological inducibility of AF following PVI was predictive for future recurrence of AF, in particular in patients with paroxysmal AF, stimulation in only CS and no use of isoproterenol.

The Effect of the Enhanced Endpoint of Pulmonary Vein Isolation on the Long-Term Success Rate of Radiofrequency Ablation for Atrial Fibrillation

Objective

This study aimed to investigate whether the enhanced endpoint of pulmonary vein isolation (PVI; intravenous injection of adenosine-triphosphate [ATP] + pacing capture + supplemental ablation) after initial PVI can reduce the long-term recurrence rate of atrial fibrillation (AF) after PVI.

Methods

Patients with paroxysmal or persistent AF undergoing catheter ablation treatment were enrolled in this study and divided into three groups according to the surgical endpoint: (1) group 1 (n = 92), in which patients were observed for 30 minutes after the initial PVI and pulmonary vein–left atrium (PV–LA) electrical conduction had not recovered; (2) group 2 (n = 99), in which patients were observed for 30 minutes after the initial PVI, then intravenously injected with ATP, and PV–LA electrical conduction had not recovered; and (3) group 3 (n = 102), in which patients were observed for 30 minutes after the initial PVI, then intravenously injected with ATP + treated with ablation line pacing, and the atrium could not be captured.

Results

Patients were followed up for 12 months after the operation. Twenty-eight patients in group 1 (30.4%), 19 patients in group 2 (19.2%), and 10 patients in group 3 (9.8%) developed a recurrence of AF. The difference between groups 1 and 3 was statistically significant (p < 0.001). At 12 months after the operation, the thickness of the left atrium, the posterior wall of the left ventricle, and the ventricular septum of the three groups of patients were significantly thinner than before the operation. Furthermore, the left ventricular ejection fraction had increased (p < 0.05 for all), and the pulmonary artery pressure had decreased (p < 0.001).

Conclusion

For patients with paroxysmal AF or persistent AF, the enhanced endpoint of PVI after the initial PVI can reduce the long-term recurrence rate of AF after PVI.

Impact of the combined use of intracardiac ultrasound and a steerable sheath visualized by a 3D mapping system on pulmonary vein isolation

BACKGROUND

A novel steerable sheath visualized on a three-dimensional mapping system has become available in this era in which a durable pulmonary vein (PV) isolation (PVI) with reduced fluoroscopy is required.

METHODS

In 60 patients who underwent a PVI with a visualized sheath (n = 30) and non-visualized conventional sheath (n = 30), the fluoroscopic time and catheter stability during the PVI were analyzed.

RESULTS

The fluoroscopic time during the transseptal access (0 [0, 0.1] vs. 1.4 [0.8, 2.3] minutes, P < .001) and PVI (0 [0, 0.1] vs. 0.4 [0.2, 1.1] minutes, P < .001) were shorter in the visualized sheath group than conventional sheath group. The procedure time during the PVI (32.0 [26.8, 36.3] vs. 41.0 [31.8, 47.3] minutes, P = .01), particularly during the right PVI (15.0 [12.8, 18.0] vs. 23.0 [15.8, 26.3] minutes, P = .009), was shorter in the visualized sheath group than conventional sheath group, however, that during the other steps was equivalent. The standard deviation of the catheter contact force during each radiofrequency application was smaller in the visualized sheath group than conventional sheath group (4.5 ± 2.7 vs. 4.9 ± 3.1 g, P = .001). The impedance drop for each lesion was larger in the visualized sheath group than conventional sheath group (10.7 ± 6.5 vs. 9.8 ± 5.5 ohms, P < .001). The incidence of acute PV reconnections per patient (30% vs. 23%, P = .56) and per PV segment (2.5% vs. 2.3%, P = .83) were similar between the two groups. No major complications occurred in either sheath group.

CONCLUSIONS

The use of visualized sheaths may reduce the fluoroscopic time and improve the catheter stability during the PVI.

Adenosine-A drug with myriad utility in the diagnosis and treatment of arrhythmias

Adenosine has been used in the emergency treatment of arrhythmia for more than nine decades. However, cardiologists are often unfamiliar about its basic mechanism and various diagnostic and therapeutic uses, considering it mainly as a therapeutic drug for supraventricular tachycardia. This article discusses the role of adenosine relevant to emergency physicians, cardiologists, and electrophysiologists. Understanding of the mechanisms of adenosine and its electrophysiological effects is discussed first, followed by dosing, side effects, diagnostic, and therapeutic uses. Finally, the role of adenosine in the electrophysiology laboratory is discussed.

A deep learning model to predict recurrence of atrial fibrillation after pulmonary vein isolation

Background and Objectives

The efficacy of radiofrequency catheter ablation (RFCA) in atrial fibrillation (AF) is well established. The standard approach to RFCA in AF is pulmonary vein isolation (PVI). However, a large proportion of patients experiences recurrence of atrial tachyarrhythmia. The purpose of this study is to find out whether the AI model can assess AF recurrence in patients who underwent PVI.

Materials and methods

This study was a retrospective cohort study that enrolled consecutive patients who underwent catheter ablation for symptomatic, drug-refractory AF and PVI. We developed an AI algorithm to predict recurrence of AF after PVI using patient demographics and three-dimensional (3D) reconstructed left atrium (LA) images.

Results

We included 527 consecutive patients in the study. The overall mean LA diameter was 42.0 ± 6.8 mm, and the mean LA volume calculated using 3D reconstructed images was 151.1 ± 46.7 ml. During the follow-up period, atrial tachyarrhythmia recurred in 158 patients. The area under the curve (AUC) of the AI model based on a convolutional neural network (including 3D reconstruction images) was 0.61 (95% confidence interval [CI] 0.53–0.74) using the test dataset. The total test accuracy was 66.3% (57.0–75.6), and the sensitivity was 53.3% (34.8–71.9). The specificity was 73.2% (51.8–75.0), and the F1 score was 52.5% 34.5–66.7).

Conclusion

In this study, we developed an AI algorithm to predict recurrence of AF after catheter ablation of PVI using individual reconstructed LA images. This AI model was unable to predict recurrence of AF overwhelmingly; therefore, further large-scale study is needed.

ASJ, Meira K, Pezzin F, Lacerda Jr. O, Batista Jr. W, Nogueira Jr. A, Amaral D. The First-Pass Isolation Effect in High-Power Short-Duration Compared to Low-Power Long-Duration Atrial Fibrillation Ablation: a Predictor of Success

Introduction: Different results are described after atrial fibrillation ablation and multiples predictors of recurrence are well established. Objective: Evaluate and analyze if first-pass isolation effect (FPI) during first atrial fibrillation (AF) ablation with high-power short-duration (HPSD) comparing to low-power long-duration (LPLD) can impact on late outcome. Methods: Observational, retrospective study, 144 patients submitted to HPSD and LPLD ablation. HPSD: 71 patients, 50 (70.42%) males, mean age 59.73 years, 52 (73.24%) hypertension, 44 (61.97%) obstructive apnea, 23 (32.39%) arterial disease, 20 (28.17%) diabetes, and 10(14.08%) stroke. CHADS2VASC2 2.57. CT: 73 patients, 50 (68.49%) males, mean age 60.7 years, 53 (72.60%) hypertension, 41 (56.16%) obstructive apnea, 28 (38.36%) arterial disease, 14 (19.17%) diabetes and 8 (10.96%) stroke. CHAD2SVASC2 2.22. Results: Recurrence occurred in 33 patients (22.92%) at 12 months follow-up, HPSD with 9 patients and LPLD with 24 patients. Higher rate of bilateral FPI were observed in HPSD patients with 62 of 71 patients comparing to 17 of 73 patients in LPLD (P < 0.00001). At the end of study 62 (87.32%) of 71 HPSD patients were in sinus rhythm comparing to 49 (67.12%) of 73 patients in LPLD (P 0.0039). Conclusion: HPSD ablation produced higher rates of FPI comparing to LPLD. HPSD compared to LPLD showed a superiority in maintaining sinus rhythm at 12 months. At patients submitted to HPSD protocol ablation, FPI could predict higher rate of sinus rhythm at 12 months follow-up.