Does periprocedural anticoagulation management of atrial fibrillation affect the prevalence of silent thromboembolic lesion detected by diffusion cerebral magnetic resonance imaging in patients undergoing radiofrequency atrial fibrillation ablation with open irrigated catheters? Results from a prospective multicenter study

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.

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, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

MRI pattern characterization of cerebral cardioembolic lesions following atrial fibrillation ablation

Background

Recognizing etiology is essential for treatment and secondary prevention of cerebral ischemic events. A magnetic resonance imaging (MRI) pattern suggestive of an embolic etiology has been described but, to date, there are no uniformly accepted criteria.

Aim

The purpose of the study is to describe MRI features of ischemic cerebral lesions occurring after transcatheter ablation of atrial fibrillation (AF).

Methods

A systematic review and meta-analysis of studies performing brain imaging investigations before and after AF transcatheter ablation was performed. The incidence of cerebral ischemic lesions after AF transcatheter ablation was the primary endpoint. The co-primary endpoints were the prevalence of the different neuroimaging features regarding the embolic cerebral ischemic lesions.

Results

A total of 25 studies, encompassing 3,304 patients, were included in the final analysis. The incidence of ischemic cerebral lesions following AF transcatheter ablation was 17.2% [95% confidence interval (CI) 12.2%-23.8%], of which a minimal fraction was symptomatic [0.60% (95% CI 0.09%-3.9%)]. Only 1.6% of the lesions (95% CI 0.9%-3.0%) had a diameter >10 mm, and in 20.5% of the cases the lesions were multiple (95% CI 17.1%-24.4%). Brain lesions were equally distributed across the two hemispheres and the different lobes; cortical location was more frequent [64.0% (95% CI 42.9%-80.8%)] while the middle cerebral artery territory was the most involved 37.0% (95% CI 27.3-48.0).

Conclusions

The prevailing MRI pattern comprises a predominance of small (<10 mm) cortical lesions, more prevalent in the territory of the middle cerebral artery.

Antithrombotic Therapy for Patients Undergoing Cardiac Electrophysiological and Interventional Procedures: JACC State-of-the-Art Review

Electrophysiological and interventional procedures have been increasingly used to reduce morbidity and mortality in patients experiencing cardiovascular diseases. Although antithrombotic therapies are critical to reduce the risk of stroke or other thromboembolic events, they can nonetheless increase the bleeding hazard. This is even more true in an aging population undergoing cardiac procedures in which the combination of oral anticoagulants and antiplatelet therapies would further increase the hemorrhagic risk. Hence, the timing, dose, and combination of antithrombotic therapies should be carefully chosen in each case. However, the maze of society guidelines and consensus documents published so far have progressively led to a hazier scenario in this setting. Aim of this review is to provide-in a single document-a quick, evidenced-based practical summary of the antithrombotic approaches used in different cardiac electrophysiology and interventional procedures to guide the busy clinician and the cardiac proceduralist in their everyday practice.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Evaluation of an adaptive, rule-based dosing algorithm to maintain therapeutic anticoagulation during atrial fibrillation ablation

Background

Cerebral thromboembolism during atrial fibrillation (AF) ablation is an infrequent (0.17%) complication in part owing to strict adherence to intraprocedural anticoagulation. Failure to maintain therapeutic anticoagulation can lead to an increase in events, including silent cerebral ischemia.

Objective

To evaluate a computerized, clinical decision support system (CDSS) to dose intraprocedural anticoagulation and determine if it leads to improved intraprocedural anticoagulation outcomes during AF ablation.

Methods

The Digital Intern dosing algorithm is an adaptive, rule-based CDSS for heparin dosing. The initial dose is calculated from the patient's weight, baseline activated clotting time (ACT), and outpatient anticoagulant. Subsequent recommendations adapt based on individual patient ACT changes. Outcomes from 50 cases prior to algorithm introduction were compared to 139 cases using the algorithm.

Results

Procedures using the dosing algorithm reached goal ACT (over 300 seconds) faster (17.6 ± 11.1 minutes vs 33.3 ± 23.6 minutes pre-algorithm, P < .001). ACTs fell below goal while in the LA (odds ratio 0.20 [0.10-0.39], P < .001) and rose above 400 seconds less frequently (odds ratio 0.21 [0.07-0.59], P = .003). System Usability Scale scores were excellent (96 ± 5, n = 7, score >80.3 excellent). Preprocedure anticoagulant, weight, baseline ACT, age, sex, and renal function were potential predictors of heparin dose to achieve ACT >300 seconds and final infusion rate.

Conclusion

A heparin dosing CDSS based on rules and adaptation to individual patient response improved maintenance of therapeutic ACT during AF ablation and was rated highly by nurses for usability.

Impact of high-power short-duration atrial fibrillation ablation technique on the incidence of silent cerebral embolism: a prospective randomized controlled study

BACKGROUND

High-power short-duration (HPSD) ablation strategy has emerged as a popular approach for treating atrial fibrillation (AF), with shorter ablation time. The utilized Smart Touch Surround Flow (STSF) catheter, with 56 holes around the electrode, lowers electrode-tissue temperature and thrombus risk. Thus, we conducted this prospective, randomized study to investigate if the HPSD strategy with STSF catheter in AF ablation procedures reduces the silent cerebral embolism (SCE) risk compared to the conventional approach with the Smart Touch (ST) catheter.

METHODS

From June 2020 to September 2021, 100 AF patients were randomized 1:1 to the HPSD group using the STSF catheter (power set at 50 W) or the conventional group using the ST catheter (power set at 30 to 35 W). Pulmonary vein isolation was performed in all patients, with additional lesions at operator's discretion. High-resolution cerebral diffusion-weighted magnetic resonance imaging (hDWI) with slice thickness of 1 mm was performed before and 24-72 h after ablation. The incidence of new periprocedural SCE was defined as the primary outcome. Cognitive performance was assessed using the Montreal Cognitive Assessment (MoCA) test.

RESULTS

All enrolled AF patients (median age 63, 60% male, 59% paroxysmal AF) underwent successful ablation. Post-procedural hDWI identified 106 lesions in 42 enrolled patients (42%), with 55 lesions in 22 patients (44%) in the HPSD group and 51 lesions in 20 patients (40%) in the conventional group (p = 0.685). No significant differences were observed between two groups regarding the average number of lesions (p = 0.751), maximum lesion diameter (p = 0.405), and total lesion volume per patient (p = 0.669). Persistent AF and CHA2DS2-VASc score were identified as SCE determinants during AF ablation procedure by multivariable regression analysis. No significant differences in MoCA scores were observed between patients with SCE and those without, both immediately post-procedure (p = 0.572) and at the 3-month follow-up (p = 0.743).

CONCLUSIONS

Involving a small sample size of 100 AF patients, this study reveals a similar incidence of SCE in AF ablation procedures, comparing the HPSD strategy using the STSF catheter to the conventional approach with the ST catheter.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04408716. AF = Atrial fibrillation, DWI = Diffusion-weighted magnetic resonance imaging, HPSD = High-power short-duration, ST = Smart Touch, STSF = Smart Touch Surround Flow.

Silent cerebral lesions following catheter ablation for atrial fibrillation: a state-of-the-art review

Atrial fibrillation is associated with neurocognitive comorbidities such as stroke and dementia. Evidence suggests that rhythm control-especially if implemented early-may reduce the risk of cognitive decline. Catheter ablation is highly efficacious for restoring sinus rhythm in the setting of atrial fibrillation; however, ablation within the left atrium has been shown to result in MRI-detected silent cerebral lesions. In this state-of-the-art review article, we discuss the balance of risk between left atrial ablation and rhythm control. We highlight suggestions to lower the risk, as well as the evidence behind newer forms of ablation such as very high power short duration radiofrequency ablation and pulsed field ablation.

Safety of a single bolus administration of heparin without the measurement of activated clotting time during cryoballoon ablation: a prospective randomized controlled trial

BACKGROUND

Single-shot ablation has emerged as an effective technique for index atrial fibrillation (AF) ablation, with an advantage of short procedure time. Although recent guidelines recommend peri-procedural uninterrupted oral anticoagulants (OACs), the intra-procedural anticoagulation strategy remains uncertain under non-vitamin K OACs (NOACs). We investigated procedural safety of a single bolus administration of heparin without activated clotting time (ACT) measurement during cryoballoon ablation (CBA).

METHODS

Two hundred patients (64.2 ± 10.0 years, 70% with non-paroxysmal AF) who underwent CBA with uninterrupted NOACs were randomly assigned to No-ACT group and ACT group. A bolus of heparin (100 U/kg) was routinely administered immediately after transseptal puncture. In the ACT group, an additional injection of heparin (30 U/kg) was administered if ACT at 30 min after the initial bolus was < 300 s.

RESULTS

There were no differences in baseline characteristics including CHA₂DS₂-VASc score between the two groups. The left atrium indwelling and procedure times were 60.4 ± 13.1 min and 78.9 ± 13.9 min, respectively, and not significantly different between the two groups. The mean ACT was 335.2 ± 59.9 s in the ACT group. Any bleeding rate was 3.2% in all patients and there was no statistically significant difference in bleeding complications between the two groups. In the ACT group, groin hematoma, laryngopharyngeal bleeding, and hemoptysis occurred in 3, 1, and 1 patient, respectively. Cardiac tamponade occurred in 1 patient in the No-ACT group. No thromboembolic events occurred during the 30-day follow-up after CBA.

CONCLUSIONS

Single bolus administration of heparin without ACT measurement is a feasible anticoagulation strategy for CBA in patients with uninterrupted NOAC intake.

Application of anti-Xa assay in monitoring unfractionated heparin therapy in contemporary antithrombotic management

INTRODUCTION

Unfractionated heparin remains the most widely used agent in the prevention and acute treatment of thrombosis. Pharmacological complexities of this intriguing agent mandate frequent monitoring of its anticoagulant properties to maintain safe and effective hematological outcomes. Although activated partial thromboplastin time has been the standard test to monitor unfractionated heparin therapy for many decades, the anti-Xa assay has emerged as a substitute or adjunct in many institutions.

AREAS COVERED

This brief report outlines the key features of anti-Xa assay in monitoring unfractionated heparin in acute management of thrombosis in various contemporary settings, with emphasis on evidence for clinical outcomes. PubMed.gov database was utilized to obtain the pertinent literature.

EXPERT OPINION

The anti-Xa activity is primarily a reflection of UFH concentration and does not account for other hematological variables frequently present in contemporary anticoagulation management. The advantage of the anti-Xa assay in monitoring UFH therapy is predicated upon its limitations to account for global physiological hemostasis. There are significant disease and drug interactions that may potentially result in false in-vitro analysis of anti-Xa activity. Routine application of the anti-Xa assay is not evidence-based at this time.

Effect of air removal with extracorporeal balloon inflation on incidence of asymptomatic cerebral embolism during cryoballoon ablation of atrial fibrillation: A prospective randomized study

Background

It was previously reported, based on a retrospective study, that preliminary removal of air bubbles in heparinized saline water with extracorporeal balloon inflation reduced the incidence of asymptomatic cerebral embolism (ACE). The present study aims to compare the incidence of ACE between a conventional and pre-inflation method during cryoballoon ablation in a prospective randomized controlled study.

Methods

A total of 98 atrial fibrillation patients were enrolled and randomized into conventional and pre-inflation groups. Patients in the pre-inflation group received balloon massaging with preliminary extracorporeal balloon inflation in saline water before the cryoballoon was inserted into the body.

Results

The baseline characteristics were similar between the two groups. Post-procedural 3-Tesla MRI revealed CE in 27.6% of patients. Symptomatic CE only occurred in two patients in the pre-inflation group. One patient had transient dysarthria and mild muscle weakness in one hand; the other patient complained of transient left upper limb weakness, left lower limb paresthesia and dysarthria. The incidence of ACE detected by cerebral MRI did not differ between the two groups to a statistically significant extent (conventional vs. pre-inflation; 22.9% vs. 29.2%; P = 0.49). In the multivariable analysis, eGFR was independently associated with the presence of ACE (odds ratio 0.95; 95% confidence interval 0.907–0.995; P = 0.03).

Conclusion

In this prospective randomized study, the preliminary removal of air bubbles in heparinized saline water with extracorporeal balloon inflation had no impact on the incidence of ACE.

MRI-Detected Brain Lesions and Cognitive Function in Atrial Fibrillation Patients Undergoing Left Atrial Catheter Ablation in the Randomized AXAFA-AFNET 5 Trial

Background: To assess the prevalence of magnetic resonance imaging (MRI) detected ischemic brain lesions and their association with cognitive function 3-months after first-time ablation using continuous oral anticoagulation in patients with paroxysmal atrial fibrillation (AF). Methods: Pre-specified analysis of the Anticoagulation using the direct factor Xa inhibitor apixaban during Atrial Fibrillation catheter Ablation: Comparison to vitamin K antagonist therapy (AXAFA-AFNET 5) trial, randomizing 674 patients with AF 1:1 to uninterrupted apixaban or vitamin K-antagonist therapy prior to first-time ablation. Brain MRI using fluid-attenuated inversion recovery (FLAIR) and high-resolution diffusion weighted imaging (hrDWI) was obtained within 3-48 hours after AF ablation in all eligible patients enrolled in 25 study centers in Europe and the United States. Patients underwent cognitive assessment 3-6 weeks before ablation and 3 months after ablation using the Montreal Cognitive Assessment (MoCA). Results: In 84 (26.1%) of 321 patients with analyzable MRI, hrDWI detected at least one acute brain lesion, including 44 (27.2%) apixaban and 40 (24.8%) vitamin K antagonist treated patients (p=0.675). Median MoCA score was similar in patients with or without acute brain lesions at 3-months after ablation (28 (IQR 26-29) vs. 28 (IQR 26-29); p=0.948). FLAIR-detected cerebral chronic white matter damage (defined as Wahlund score ≥4 points) was present in 130 (40.5%) patients and associated with lower median MoCA scores before ablation (27 (24-28) vs. 27 (IQR 25-29); p=0.026) and 3-months after ablation (27 (IQR 25-29) vs. 28 (IQR 26-29); p=0.011). Adjusted for age and gender, this association was no longer significant. Age was associated with lower MoCA scores before ablation (RR 1.02 per 10 years (95%CI 1.01-1.03)) and 3-months after ablation (RR 1.02 per 10 years (95%CI 1.01-1.03)). Conclusions: Brain MRI-detected chronic white matter damage as well as acute ischemic lesions were frequently found after first-time ablation for paroxysmal AF using uninterrupted oral anticoagulation. hrDWI-detected acute ischemic brain lesions were not associated with cognitive function at 3-months after ablation. Lower MoCA scores before and after ablation were associated with old age only, highlighting the safety of AF ablation on uninterrupted oral anticoagulation.

Atrial Fibrillation Ablation Using Robotic Magnetic Navigation Reduces the Incidence of Silent Cerebral Embolism

Background: The incidence of silent cerebral embolisms (SCEs) has been documented after pulmonary vein isolation using different ablation technologies; however, it is unreported in patients undergoing with atrial fibrillation (AF) ablation using Robotic Magnetic Navigation (RMN). The purpose of this prospective study was to investigate the incidence, risk predictors and probable mechanisms of SCEs in patients with AF ablation and the potential impact of RMN on SCE rates.

Methods and Results: We performed a prospective study of 166 patients with paroxysmal or persistent AF who underwent pulmonary vein isolation. Patients were divided into RMN group (n = 104) and manual control (MC) group (n = 62), and analyzed for their demographic, medical, echocardiographic, and risk predictors of SCEs. All patients underwent cerebral magnetic resonance imaging within 48 h before and after the ablation procedure to assess cerebral embolism. The incidence and potential risk factors of SCEs were compared between the two groups. There were 26 total cases of SCEs in this study, including 6 cases in the RMN group and 20 cases in the MC group. The incidences of SCEs in the RMN group and the MC group were 5.77 and 32.26%, respectively (X² = 20.63 P < 0.05). Univariate logistic regression analysis demonstrated that ablation technology, CHA₂DS₂-VASc score, history of cerebrovascular accident/transient ischemic attack, and low ejection fraction were significantly associated with SCEs, and multivariate logistic regression analysis showed that MC ablation was the only independent risk factor of SCEs after an AF ablation procedure.

Conclusions: Ablation technology, CHA₂DS₂-VASc score, history of cerebrovascular accident/transient ischemic attack, and low ejection fraction are associated with SCEs. However, ablation technology is the only independent risk factor of SCEs and RMN can significantly reduce the incidence of SCEs resulting from AF ablation.

Clinical Trial Registration: ChiCTR2100046505.

The AF-FICIENT magnetic resonance imaging and endoscopy safety substudy: A visually guided radiofrequency balloon ablation catheter for pulmonary vein isolation

Background

Early experience with a novel multielectrode saline-irrigated radiofrequency balloon (RFB) catheter with an integrated camera system found that it was safe and effective in performing single-shot pulmonary vein isolation (PVI) for atrial fibrillation.

Objective

The purpose of this study was to further assess potential treatment risks by looking for subclinical events.

Methods

The study was performed at 2 sites. Patients underwent PVI by RFB. A control group underwent conventional point-by-point radiofrequency ablation. Stroke scale questionnaire and brain magnetic resonance imaging (MRI) were performed before and after the ablation procedure, and esophageal endoscopy was performed after the procedure in RFB patients only.

Results

We enrolled 27 patients in the RFB group and 15 patients in the control group. The RFB and control groups were well matched [predominantly male: 62% vs 53%; CHA₂DS₂-VASc score: 1.9 ± 1.3 vs 1.5 ± 1.6; mean age 60 years in both groups]. All patients underwent successful ablation and completed study assessments. Clinically silent, new MRI diffusion weighted imaging cerebral lesions were observed in 8 patients (30%) in the RFB group and 1 patient (7%) in the control group, and 11 susceptibility weighted imaging lesions in the RFB group and 1 in the control group. Endoscopy showed a minor thermal injury in 1 patient in the RFB group.

Conclusion

An increased rate of clinically silent cerebral events was seen in the RFB group. A low rate of esophageal thermal injury was observed.

Symptomatic and asymptomatic intracerebral hemorrhages detected by magnetic resonance imaging after catheter ablation of atrial fibrillation

PURPOSE

Symptomatic intracerebral hemorrhages (ICHs) are a rare complication after atrial fibrillation (AF) catheter ablation, while the incidence of asymptomatic ICHs detected by magnetic resonance (MR) imaging remains unclear. This study aimed to investigate the incidence, characteristics, and predictors of new-onset ICHs on MR imaging after AF ablation.

METHODS

We retrospectively studied 1257 consecutive AF ablation procedures in 1201 patients who underwent MR imaging on the day after the procedure. Repeat MR imaging within 3 months post-ablation was available in 352 procedures.

RESULTS

Old ICHs on the initial MR imaging were observed in 28 procedures (2.2%). Post-ablation new ICHs were observed in 14 procedures (4.0%), including one symptomatic (0.3%) and 13 (3.7%) asymptomatic ICHs. One patient had a new ICH on the initial MR imaging, while the remaining 13 had such on the repeat MR imaging. A univariate analysis revealed that a previous ischemic stroke or transient ischemic attack (TIA) and the CHA₂DS₂-VASc score were positive predictors of new ICHs (odds ratios, 5.502 and 1.435; P = 0.004 and 0.044). The lesion diameter did not significantly differ between the old and new ICHs (median, 6.1 mm vs. 8.0 mm, P = 0.281), while the predominant location differed (lobar areas, 22.6% vs. 53.3%; cerebellum, 22.6% vs. 20.0%; others, 54.8% vs. 26.7%; P = 0.026).

CONCLUSIONS

A few asymptomatic ICHs may occur after AF ablation. Most of the post-ablation new ICHs occurred a few days or later after the procedure. A previous ischemic stroke/TIA and the CHA₂DS₂-VASc score may be risk factors for post-ablation ICHs.

Incidence and risk factors of post-operative cognitive decline after ablation for atrial fibrillation

Background

Catheter ablation is widely used in atrial fibrillation (AF) management. In this study, we are aimed to investigate the incidence of postprocedural cognitive decline in a larger population undergoing AF ablation under local anesthesia, and to evaluate the associated risk factors.

Methods

This study included 287 patients with normal cognitive functions, with 190 ablated AF patients (study group) and 97 AF patients who are awaiting ablation (practice group). We assessed the neuropsychological function of each patient for twice (study group: 24 h prior to ablation and 48 h post ablation; practice group: on the day of inclusion and 72 h later but before ablation). The reliable change index was used to analyze the neuropsychological testing scores and to identify postoperative cognitive dysfunction (POCD) at 48 h post procedure. Patients in the study group accepting a 6-month follow up were given an extra cognitive assessment.

Results

Among the ablated AF patients, 13.7% (26/190) had POCD at 48 h after the ablation procedure. Multivariable analysis revealed that, a minimum intraoperative activated clotting time (ACT) < 300 s (OR 3.82, 95% CI 1.48–9.96, P = 0.006) and not taking oral anticoagulants within one month prior to ablation(OR 10.35, 95% CI 3.54–30.27, P < 0.001) were significantly related to POCD at 48 h post-ablation. In 172 patients of the study group accepting a 6-month follow up, there were 23 patients with POCD at 48 h post-ablation and 149 patients without POCD. The global cognitive scores were decreased in 48 h post-operation tests (0 ± 1 vs − 0.15 ± 1.10, P < 0.001) and improved significantly at 6 months post-operation (0 ± 1 vs 0.43 ± 0.92, P < 0.001). In the 23 patients with POCD at 48 h after the procedure, global cognitive performance at 6 months was not significantly different compared with that at baseline (− 0.05 ± 1.25 vs − 0.19 ± 1.33, P = 0.32), while 13 of them had higher scores than baseline level.

Conclusions

Incident of POCD after ablation procedures is high in the short term. Inadequate periprocedural anticoagulation are possible risk factors. However, most POCD are reversible at 6 months, and a general improvement was observed in cognitive function at 6 months after ablation.

Anticoagulant therapy in catheter ablation of atrial fibrillation and flutter

Catheter ablation (CA) of atrial fibrillation and flutter is associated with a high risk of both perioperative thromboembolic events and bleeding. Adequate anticoagulation is imperative to reduce the risk of complications. The aim of this review was to analyze modern approaches to anticoagulant therapy for CA of atrial fibrillation and flutter, as well as provide practical information based on a comparison of current guidelines and evidence base. The search for literature sources on anticoagulant therapy in CA was carried out in the PubMed, Scopus, Web of Science databases. The results of key randomized trials and meta-analyzes are presented, and a comparison of current Russian and international guidelines is given. Unresolved issues requiring further research are discussed.

The Efficacy and Safety of Hybrid Ablations for Atrial Fibrillation

OBJECTIVES

This study sought to comprehensively determine the procedural safety and midterm efficacy of hybrid ablations.

BACKGROUND

Hybrid ablation of atrial fibrillation (AF) (thoracoscopic ablation followed by catheter ablation) has been used for patients with nonparoxysmal AF; however, accurate data regarding efficacy and safety are still limited.

METHODS

Patients with nonparoxysmal AF underwent thoracoscopic, off-pump ablation using the COBRA Fusion radiofrequency system (Estech) followed by a catheter ablation 3 months afterward. The safety of the procedure was assessed using sequential brain magnetic resonance and neuropsychological examinations at baseline (1 day before), postoperatively (2-4 days for brain magnetic resonance imaging or 1 month for neuropsychological examination), and at 9 months after the surgical procedure. Implantable loop recorders were used to detect arrhythmia recurrence. Arrhythmia-free survival (the primary efficacy endpoint) was defined as no episodes of AF or atrial tachycardia while off antiarrhythmic drugs, redo ablations or cardioversions.

RESULTS

Fifty-nine patients (age: 62.5 ± 10.5 years) were enrolled, 37 (62.7%) were men, and the mean follow-up was 30.3 ± 10.8 months. Thoracoscopic ablation was successfully performed in 55 (93.2%) patients. On baseline magnetic resonance imaging, chronic ischemic brain lesions were present in 60% of patients. New ischemic lesions on postoperative magnetic resonance imaging were present in 44.4%. Major postoperative cognitive dysfunction was present in 27.0% and 17.6% at 1 and 9 months postoperatively, respectively. The probability of arrhythmia-free survival was 54.0% (95% CI: 41.3-66.8) at 1 year and 43.8% (95% CI: 30.7-57.0) at 2 years.

CONCLUSIONS

The thoracoscopic ablation is associated with a high risk of silent cerebral ischemia. The midterm efficacy of hybrid ablations is moderate.

Comprehensive Intraprocedural Unfractionated Heparin Protocol During Catheter Ablation of Atrial Fibrillation in the Presence of Direct Oral Anticoagulants and Wide Spectrum of Body Mass Index

INTRODUCTION

Data on optimal dosing of unfractionated heparin (UFH) in the presence of a direct oral anticoagulant (DOAC) to achieve and maintain an activated clotting time (ACT) of ≥300 seconds during catheter ablation of atrial fibrillation (CA-AF) are limited and prevalence of obesity adds to the unpredictable response to UFH.

METHODS AND RESULTS

One hundred seventeen consecutive patients undergoing CA-AF were prospectively administered weight-adjusted, weight-based UFH using a pre-specified detailed protocol and retrospectively analyzed. Due to lack of distribution of UFH into muscle or adipose tissue and lower degree of vascularity in the latter compartment, each patient's ideal and actual weights were used to determine the adjusted-weight for use in all UFH doses. A UFH bolus of 200 units/kg was administered intravenously followed by an infusion of 35 units/kg/hour. The mean age was 65 years, and 85 patients (72.6%) were male. The average body mass index (BMI) was 30 (range 18-50) kg/m². After the initial UFH bolus dose, 99 patients (84.6%) achieved ACT ≥300 sec with a mean (± SD) of 380 ± 79 sec. The mean time to reach an ACT ≥300 in all patients was 14.6 ± 12.4 minutes. Among all measured ACT values, 423 (90.8%) were ≥300 seconds. These results were consistent within all BMI categories. There were no intraprocedural thrombotic or hemorrhagic complications. Two patients (1.7%) sustained groin vascular access site hematoma without subsequent intervention and 7 patients (6%) experienced minor oozing post-procedurally.

CONCLUSIONS

Our comprehensive weight-adjusted, weight-based UFH protocol, during CA-AF in presence of a DOAC, rapidly achieved and maintained an effective ACT irrespective of BMI.

Protocol driven periprocedural anticoagulation for left atrial ablation

INTRODUCTION

A weight-based heparin dosing policy adjusted for preprocedural oral anticoagulation was implemented to reduce the likelihood of subtherapeutic dosing during left atrial catheter ablation procedures. We hypothesized that initiation of the protocol would result in a greater prevalence of therapeutic activated clotting time (ACT) values and decreased time to therapeutic ACT during left atrial ablation procedures.

METHODS

A departmental protocol was initiated for which subjects received intravenous unfractionated heparin (UFH) to achieve and maintain a goal of ACT >300 s. Initial bolus dose was adjusted for pre-procedure oral anticoagulation and weight as follows: 50 units/kg for those receiving warfarin, 75 units/kg for those not anticoagulated, and 120 units/kg for those on direct oral anticoagulants (DOACs). A UFH infusion was initiated at 10% of the bolus per hour. One hundred consecutive left atrial ablation procedures treated with Protocol Guided heparin dosing were compared with a retrospective consecutive cohort of Usual Care heparin dosing.

RESULTS

When the Usual Care and Protocol Guided cohorts were compared, significant findings were limited to those on pre-procedure DOAC. The initial UFH bolus increased from 99.3 ± 24.8 to 118.2 ± 22.8 units/kg (p < .001), the proportion of therapeutic ACT on the first draw after heparin administration increased from 57.7% to 76.6% (p = .010), and the time to therapeutic ACT after UFH administration decreased from 37.8 ± 19.8 to 30.2 ± 16.4 min (p = .032).

CONCLUSION

A weight-based protocol for periprocedural UFH administration resulted in a higher proportion of therapeutic ACT values and decreased the time to therapeutic ACT for those on pre-procedure DOAC.

Effect of preventing air intrusion on silent strokes during atrial fibrillation ablation using a mini-basket catheter

BACKGROUND

Air bubble intrusion through transseptal sheaths during left atrial (LA) catheter ablation can cause cerebral embolisms, especially when using complex-shape catheters. This study aimed to compare the incidence of silent cerebral events (SCEs) after atrial fibrillation (AF) catheter ablation using a mini-basket catheter (IntellaMap Orion; Boston Scientific) between the following groups: group SP, strict prevention of LA air intrusion and group CP, conventional air intrusion prevention.

METHODS

We enrolled 123 consecutive AF patients (group SP, n = 61 and group CP, n = 62) who underwent brain magnetic resonance imaging after a local-impedance-guided ablation using one mini-basket catheter and one circular mapping catheter. The preventive strategy in group SP included (a) the insertion of the mini-basket catheter into the transseptal sheaths in a container filled with heparinized saline and (b) no exchange of all catheters over the sheaths.

RESULTS

SCEs were detected in 67 patients (54.5%), and the incidence of SCEs did not significantly differ between groups SP and CP (55.7% vs 53.2%; P = .780). A multivariate analysis demonstrated that an older age, non-paroxysmal AF, and radiofrequency (RF) power output were independent positive predictors of SCEs (odds ratios: 1.079, 5.613, and 1.405; P = .005, <.001, and .012). On the follow-up MR imaging, 83.5% of the SCEs in group SP and 87.7% in group CP disappeared (P = .398).

CONCLUSIONS

Strict prevention of LA air intrusion may have no additional effect for reducing the incidence of SCEs after local impedance-guided AF ablation using a mini-basket catheter. An older age, non-paroxysmal AF, and high-power RF applications may increase the risk of SCEs.

Incidence and characteristics of silent cerebral embolisms after radiofrequency-based atrial fibrillation ablation: A propensity score-matched analysis between different mapping catheters and indices for guiding ablation

INTRODUCTION

The difference in the incidence and characteristics of silent cerebral events (SCEs) after radiofrequency-based atrial fibrillation (AF) ablation between the different mapping catheters and indices used for guiding radiofrequency ablation remains unclear. This study aimed to compare the incidence and characteristics of postablation SCEs between the following two groups: Group C, Ablation Index-guided ablation using two circular mapping catheters with CARTO (Biosense Webster); Group R, local impedance-guided ablation using one mini-basket catheter and one circular mapping with Rhythmia (Boston Scientific).

METHODS AND RESULTS

Of 211 consecutive patients who underwent an AF ablation and brain magnetic resonance (MR) imaging after the ablation, 120 patients (each group, n = 60) were selected by propensity score matching. SCEs were detected in 37 patients (30.8%). Group R had a higher incidence of SCEs (51.7% vs. 10.0%; p < .001) and more SCEs per patient (median, 3 vs. 1, p = .028) than Group C. A multivariate analysis demonstrated that nonparoxysmal AF and being Group R were independent positive predictors of SCEs (odds ratios, 6.930 and 15.464; both p < .001). On the follow-up MR imaging, all SCEs in Group C and 87.9% of the SCEs in Group R disappeared (p = .537).

CONCLUSIONS

Group R had a significantly higher incidence of SCEs than Group C. Most probably the use of a complexly designed basket mapping catheter is the reason for the difference in the incidence of SCEs but further validation is needed. A nonparoxysmal form of AF may also increase the risk of SCEs during these ablation procedures.

Long-Term Outcomes of Left Atrial Appendage Electrical Isolation in Patients With Nonparoxysmal Atrial Fibrillation

Background:

Left atrial appendage electrical isolation (LAAEI) has been proposed for the treatment of nonparoxysmal atrial fibrillation (AF). The long-term clinical outcomes of this approach remain unclear. The objective of our study was to investigate the incremental benefit and safety of LAAEI in patients undergoing catheter ablation for nonparoxysmal AF.

Methods:

Propensity score-matched analysis was performed using a prospective registry database from 2010 to 2014. All patients in the LAAEI group were matched based on baseline characteristics, echocardiographic parameters, and procedural ablation techniques.

Results:

We identified 1842 patients who underwent catheter ablation for nonparoxysmal AF. Propensity score matching yielded 1092 patients, 546 patients with LAAEI, and 546 patients without LAAEI. At 5-year follow-up, overall freedom from all-atrial arrhythmia recurrence, off-antiarrhythmic drugs, in patients who underwent LAAEI was 68.9% versus 50.2% in those who underwent standard ablation alone ( P <0.001). Acute complication rates were similar between groups (LAAEI 1.3% versus non-LAAEI 0.73%, P =0.36). At 5-year follow-up, 382 (70%) patients in the LAAEI group remained on oral anticoagulation versus 217 (39.7%) in the non-LAAEI group. At 5-year follow-up, thromboembolic events occurred in 15/546 (2.75%) in the LAAEI group and 4/546 (0.73%) in the non-LAAEI group ( P =0.01). No thromboembolic events occurred in either group on-oral anticoagulation. In patients who were off-oral anticoagulation, at 5-year follow-up, thromboembolic events occurred in 15/164 (9.1%) in the LAAEI group and 4/329 (1.2%) in the non-LAAEI group ( P <0.001).

Conclusions:

At 5-year follow-up, LAAEI was associated with significantly higher freedom from all-atrial arrhythmia recurrence in patients with persistent and long-standing persistent AF without increasing acute procedural complication rate. In patients off-oral anticoagulation, there appears to be a higher risk of thromboembolic events in the LAAEI group.

Uninterrupted use of direct oral anticoagulants versus vitamin K antagonists for catheter ablation of atrial fibrillation with PVAC gold: incidence of silent cerebral microembolic events

BACKGROUND

Silent cerebral microembolic events (SCE) after duty-cycled ablation of atrial fibrillation using PVAC have been detected by cerebral magnet resonance imaging (MRI) in a substantial number of patients. The purpose of this study was to investigate if uninterrupted oral anticoagulation with non-vitamin K antagonists (NOACs) compared with vitamin K antagonists (VKA) affects the incidence of SCE after pulmonary vein isolation (PVI) using PVAC Gold.

METHODS

Eighty-four consecutive patients (62 ± 15 years, 58% male) undergoing a first PVI were prospectively enrolled. Of these, 42 were on VKA and 42 on uninterrupted NOAC treatment. An activated clotting time (ACT) ≥ 350 s was targeted for ablation.

RESULTS

Cerebral MRI the day after PVI revealed acute diffusion-weighted positive lesions in 11/42 (26%) VKA compared with 14/42 (33%) in NOAC patients (p = 0.634). No differences were found for lesion size, number of lesions/patient, and number of lesions indicating cerebral infarction (2.4% for VKA and 4.8% for NOAC patients). Seventy-five percent of NOAC patients with sporadic ACT levels < 300 s during PVI developed SCE compared with 22% of corresponding VKA patients (p = 0.030). VKA and NOAC subgroups with ACT ≥ 350 s had no reduced incidence of SCE compared with ACT 300-350 s.

CONCLUSIONS

A significant, but comparable, number of patients under uninterrupted anticoagulation with VKA or NOACs still experience SCE after PVAC Gold PVI. NOAC patients with sporadic subtherapeutic ACT levels during PVI are at the highest risk for SCE while permanent ACT levels ≥ 350 s did not further reduce the incidence of SCE in both groups.

Safety of Catheter Ablation of Atrial Fibrillation Under Uninterrupted Rivaroxaban Use

Fundamento:

A ablação de fibrilação atrial (FA) sob uso ininterrupto de varfarina é segura e recomendada por especialistas. Entretanto, há controvérsia quanto aos anticoagulantes orais de ação direta para o mesmo fim.

Objetivo:

Avaliar a segurança em realizar ablação de FA sob anticoagulação ininterrupta com rivaroxabana.

Métodos:

Uma série de 130 pacientes foi submetida à ablação com radiofrequência da FA sob uso ininterrupto de rivaroxabana (grupo RIV) e comparada a um grupo-controle de 110 pacientes que a fizeram sob uso ininterrupto de varfarina (grupo VRF) e relação normatizada internacional (RNI) terapêutica. Analisamos morte, taxas de eventos tromboembólicos, de sangramentos maiores e menores, níveis do tempo de coagulação ativado (TCA) e dose de heparina no procedimento. O protocolo da ablação consistiu basicamente em isolamento circunferencial das veias pulmonares guiado por mapeamento eletroanatômico. Significância estatística de 5% foi adotada.

Resultados:

As características clínicas dos grupos foram semelhantes e a FA paroxística mais frequente (63% e 59%, grupos RIV e VRF). Um evento tromboembólico ocorreu no grupo RIV. Foram três pacientes com sangramentos maiores (RIV = 1 e VRF = 2; p = 0,5); nenhum óbito. A RNI basal foi maior no grupo VRF (2,5 vs. 1,2 ± 0,02; p < 0,0001), com níveis de TCA basal semelhantes (123,7 ± 3 vs. 118 ± 4; p = 0,34). Maior dose de heparina venosa foi utilizada no grupo RIV (9.414 ± 199 vs. 6.019 ± 185 UI; p < 0,0001) para manter níveis médios de TCA semelhantes durante o procedimento (350 ± 3 vs. 348,9 ± 4; p = 0,79).

Conclusão:

Na população estudada, a ablação de FA sob rivaroxabana ininterrupta teve segurança equivalente à varfarina ininterrupta, com RNI terapêutica.

Periprocedural and long-term safety and feasibility of direct oral anticoagulants in patients with biological valve undergoing radiofrequency catheter ablation for atrial fibrillation: a prospective multicenter study

BACKGROUND

Direct oral anticoagulants (DOACs) are contraindicated in patients with atrial fibrillation (AF) and mechanical cardiac valves. However, safety and efficacy are controversial in patients with biological cardiac valves.

OBJECTIVE

We report the safety and feasibility of periprocedural and long-term treatment with DOACs in patients with biological valves undergoing ablation for AF.

METHODS

A total of 127 patients with AF and biological cardiac valve undergoing CA on uninterrupted DOAC were matched by gender and age with 127 patients with AF and biological cardiac valves undergoing CA on uninterrupted warfarin. All patients were anticoagulated for at least 3-4 weeks prior to ablation with either rivaroxaban (70%) or apixaban (30%), which were continued for at least 3 months and subsequently based on CHA₂DS₂-VASc score.

RESULTS

Mean age of the study population was 63.0 ± 10.9 with 66% being male. The majority of patients on NOACs had aortic valve replacement (59%), while mitral valve was replaced in 41% of patients, which did not differ from the matched cohort on coumadin (aortic valve 57% and mitral valve 43%, (p = 0.8) (p = 0.8), respectively). The CHADS₂ score was ≥ 2 in 90 patients (71.0%) on DOAC and 86 patients in (68%) the control (p = 0.6) group. Patients underwent ablation predominantly with uninterrupted rivaroxaban [89 (70%)], while the remaining 38 patients (30%) underwent ablation while on apixaban. Two groin hematomas were observed periprocedurally in both groups. No stroke/transient ischemic attack (TIA) was observed both periprocedurally and at long-term follow-up in either group.

CONCLUSION

Periprocedural and long-term administration of DOACs in patients with biological cardiac valves undergoing AF ablation appears as safe as warfarin therapy.

Factors associated with silent cerebral events during atrial fibrillation ablation in patients on uninterrupted oral anticoagulation

INTRODUCTION

Silent cerebral events (SCEs) are related to the potential thromboembolic risk in atrial fibrillation (AF) ablation. Periprocedural uninterrupted oral anticoagulation (OAC) reportedly reduced the risk of SCEs, but the incidence still remains.

METHODS AND RESULTS

AF patients undergoing catheter ablation were eligible. All patients took non-vitamin K antagonist oral anticoagulants (NOACs; n = 248) or vitamin K antagonist (VKA; n = 37) for periprocedural OAC (>4 weeks) without interruption during the procedure. Brain magnetic resonance imaging was performed within 2 days after the procedure to detect SCEs. Clinical characteristics and procedure-related parameters were compared between patients with and without SCEs. SCEs were detected in 66 patients (23.1%; SCE[+]) but were not detected in 219 patients (SCE[-]). Age was higher in SCE[+] than in SCE[-] (66 ± 10 vs. 62 ± 12 years; p < .05). Persistent AF prevalence, CHADS₂ /CHA₂ DS₂ -VASc scores, serum NT-ProBNP levels, left atrial dimension (LAD), and spontaneous echo contrast prevalence in transesophageal echocardiography significantly increased in SCE[+] versus SCE[-]. SCE[+] had lower baseline activated clotting time (ACT) before heparin injection and longer time to reach optimal ACT (>300 s) than SCE[-] (146 ± 27 vs. 156 ± 29 s and 44 ± 30 vs. 35 ± 25 min; p < .05, respectively). In multivariate analysis, age, LAD, baseline ACT, and time to reach the optimal ACT were predictors for SCEs. The average values of the ACT parameters were significantly different among NOACs/VKA.

CONCLUSION

Age, LAD, and intraprocedural ACT kinetics significantly affect SCEs during AF ablation. Different anticoagulants have different impacts on ACT during the procedure, which should be considered when estimating the risk of SCEs.

Direct Oral Anticoagulants in the Setting of Catheter Ablation of Atrial Fibrillation: State of art

Atrial fibrillation (AF) represents the arrhythmia of greatest clinical impact and catheter ablation of AF (CAAF) has become the most effective strategy for rhythm control in selected patients. Therefore, appropriate anticoagulation strategies are of paramount importance for patients undergoing CAAF, especially those at high risk, such those with high CHA2DS2VASc scores. Optimal management of anticoagulation before, during, and after CAAF is crucial. Several studies have evaluated the use of different anticoagulation strategies in the periprocedural period. Randomized controlled trial seem to suggest that in patients undergoing CAAF, uninterrupted (or minimally interrupted) direct oral anticoagulants (DOACs) provides an alternative to continuous vitamin K antagonists strategy, with low thromboembolic and bleeding risk.

Intracardiac Fibrinolysis and Endothelium Activation Related to Atrial Fibrillation Ablation with Different Techniques

Objective

The effect of pulmonary vein isolation (PVI) on fibrinolytic and endothelial activation with currently applied periprocedural anticoagulation has not been explored. We measured markers of fibrinolysis and endothelium activation before and after PVI with the second-generation cryoballoon (Cryo), pulmonary vein ablation catheter (PVAC-Gold), and irrigated radiofrequency (IRF).

Methods

Markers of fibrinolysis and endothelium activation in left atrial (LA) blood samples were measured in 31 patients before and after PVI (Cryo:10, PVAC-Gold: 7, IRF: 14). Periprocedural anticoagulation included uninterrupted vitamin K antagonist and iv heparin (ACT≥300 sec) during LA dwelling.

Results

Levels of D-dimer (median; interquartile range, mgFEU/L) increased with all techniques (PVAC: 0.34; 0.24–0.50 versus 0.70; 0.61–1.31; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAP complex level (ng/ml) increased after Cryo (247.3, 199.9–331.6 versus 270.9, 227.9–346.7; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAI-1 activity (%) decreased with the PVAC (1.931; 0.508–3.859 versus 0.735, 0.240–2.707; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; VWF antigen levels and FVIII activity increased after PVI with all the 3 techniques. The levels of soluble VCAM-1 (ng/ml) did not change after PVAC procedures, but increased after Cryo (542, 6; 428.5–753.1 versus 619.2; 499.8–799.0; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93;

Conclusion

PVI with contemporary ablation techniques and periprocedural antithrombotic treatment induces coagulation and endothelium activation of similar magnitude with different ablation methods.

Activated Clotting Time Monitoring during Atrial Fibrillation Catheter Ablation: Does the Anticoagulant Matter?

Atrial fibrillation (AF) catheter ablation is performed in patients receiving direct oral anticoagulants (DOACs) with intra-procedural unfractionated heparin (UFH) administration to achieve activated clotting time (ACT) at 300 s, as for vitamin K antagonist (VKA). We determined whether ACT monitoring might be transposed from VKA to DOAC-treated patients. Blood was taken from 124 patients receiving uninterrupted dabigatran, rivaroxaban, apixaban, or VKA or being untreated. DOAC concentration or INR (VKA) were measured. ACT was determined at baseline, and after spiking with UFH doses equivalent to 1000, 2500, 5000 and 10000 IU in vivo. At baseline, anticoagulants prolonged ACT differently, ACT was longer with dabigatran and shorter with apixaban despite similar concentrations. ACT strongly correlated with INR and dabigatran concentration, but not with apixaban or rivaroxaban concentrations. Moreover, UFH effects on ACT prolongation depended on the anticoagulant: dose-response curves in samples with VKA and dabigatran were parallel whereas ACT prolongation in response to UFH was significantly smaller with rivaroxaban and especially apixaban. Therefore, UFH to achieve ACT at 300 s might be transposed from VKA to uninterrupted dabigatran-treated patients but not to patients receiving FXa-inhibitors, especially apixaban. Targeting 300 s might expose to UFH overdosing and bleeding, questioning the current anticoagulation strategy.

Higher Incidence of Asymptomatic Cerebral Emboli After Atrial Fibrillation Ablation Found With High-Resolution Diffusion-Weighted Magnetic Resonance Imaging

Background:

Asymptomatic cerebral emboli (ACE) are commonly seen on cerebral magnetic resonance imaging (MRI) after atrial fibrillation ablation, but the incidence in previous studies varies widely. No data exists to compare the effects of different diffusion-weighted imaging (DWI) settings on detecting ablation-related ACE. This self-control study sought to compare the incidence and characteristics of ablation-related ACE between high-resolution DWI and conventional DWI.

Methods:

A total of 55 consecutive patients referred for atrial fibrillation ablation between December 2017 and September 2018 were enrolled. Patients underwent high-resolution DWI 1 day before ablation and repeated high-resolution DWI and conventional DWI within 48 hours post-ablation. The incidence, number, size, and location of ACE were compared between 2 DWI settings in the same patients.

Results:

The high-resolution DWI revealed a higher incidence of acute ACE compared with conventional DWI (67.3% versus 41.8% of patients, P <0.001) and significantly more ACE (106 versus 45 lesions, P =0.001). For ACE seen on both scans, the size measured by high-resolution DWI was larger (5.42 versus 4.21 mm, P <0.001). No patients had any impaired neurocognitive performance during follow-up. Impaired left ventricular ejection fraction ( P =0.012) and low intraoperative activated clotting time ( P =0.009) level were associated with the occurrence of ACE in a multivariate analysis.

Conclusions:

High-resolution DWI revealed a higher incidence and greater details of post-ablation ACE in patients with atrial fibrillation. MRI settings significantly impact the detection of ACE and should be considered when comparing incidence rates of ACE among different studies.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01761188.

Impact of the type of electroanatomic mapping system on the incidence of cerebral embolism after radiofrequency catheter ablation of left atrial tachycardias

BACKGROUND

Left atrial tachycardias (ATs) often occur after left atrial ablation. The incidence of symptomatic and silent cerebral embolism after radiofrequency catheter ablation of left ATs and the impact of the type of 3-dimensional electroanatomic mapping (3D-EAM) system on the incidence of cerebral embolism remain unclear.

OBJECTIVES

This study aimed to investigate the incidence of cerebral embolism after a 3D-EAM system-guided left AT ablation procedure and compare that between the different 3D-EAM systems.

METHODS

We prospectively enrolled 59 patients who underwent left AT ablation and brain magnetic resonance imaging after the procedure: 30 were guided by the Rhythmia system (Boston Scientific, Marlborough, MA) and 29 by the CARTO system (Biosense Webster, Diamond Bar, CA) (groups R and C, respectively).

RESULTS

One transient ischemic attack occurred in group R, and no symptomatic embolism occurred in group C. Silent cerebral ischemic lesions (SCILs) were observed in 35 patients (59.3%), and group R had a significantly higher incidence of SCILs than did group C (86.2% vs 33.3%; P < .001). In multivariate analysis, group R and left atrial linear ablation were independent positive predictors of SCILs (odds ratio 12.822 and 8.668; P = .001 and P = .005). The incidence of bleeding complications was comparable between groups R and C (0% vs 3.3%; P = .508).

CONCLUSION

Group R exhibited a higher incidence of postablation cerebral embolism than did group C. The use of the high-resolution 3D-EAM system with a mini-basket catheter to guide radiofrequency ablation of left atrial macroreentrant tachycardias may markedly increase the risk of silent cerebral embolism. The present results require further validation in a randomized study.

Cognitive dysfunction in atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in adults, and its incidence and prevalence increase with age. The risk of cognitive impairment and dementia also increases with age, and both AF and cognitive impairment or dementia share important risk factors. In meta-analyses of published studies, AF is associated with a 2.4-fold and 1.4-fold increase in the risk of dementia in patients with or without a history of stroke, respectively. This association is independent of shared risk factors such as hypertension and diabetes mellitus. Neuroimaging has illustrated several potential mechanisms of cognitive decline in patients with AF. AF is associated with increased prevalence of silent cerebral infarcts, and more recent data also suggest an increased prevalence of cerebral microbleeds with AF. AF is also associated with a pro-inflammatory state, and the relationship between AF-induced systemic inflammation and dementia remains to be investigated. Preliminary reports indicate that anticoagulation medication including warfarin can reduce the risk of cognitive impairment in patients with AF. Catheter ablation, increasingly used to maintain sinus rhythm in patients with AF, is associated with the formation of new silent cerebral lesions. The majority of these lesions are not detectable after 1 year, and insufficient data are available to evaluate their effect on cognition. Large prospective studies are urgently needed to confirm the association between AF and dementia, to elucidate the associated mechanisms, and to investigate the effect of anticoagulation and rhythm control on cognition.

Asymptomatic Cerebral Infarction During Catheter Ablation for Atrial Fibrillation: Comparing Uninterrupted Rivaroxaban and Warfarin (ASCERTAIN)

OBJECTIVES

This randomized study compared uninterrupted rivaroxaban therapy with warfarin therapy as prophylaxis against catheter ablation (CA)-induced asymptomatic cerebral infarction (ACI) and identified the risk factors of rivaroxaban.

BACKGROUND

The reported incidence of ACI during CA for atrial fibrillation (AF) remains at 10% to 30%, and periprocedural oral anticoagulation could affect this incidence.

METHODS

Patients with nonvalvular AF undergoing radiofrequency CA were randomly assigned to receive either uninterrupted rivaroxaban or warfarin as periprocedural anticoagulation therapy. CA was performed after at least 1 month of adequate anticoagulation. Cerebral magnetic resonance imaging (MRI) was performed within 2 weeks before and 1 day after CA to detect ACI.

RESULTS

A total 132 patients were enrolled; 127 (median: 60.0 years of age; 83.5% males; 64.6% incidence of paroxysmal AF) complied with the study protocol and were analyzed; 64 patients received rivaroxaban, and 63 patients received warfarin. The rates of CA-induced ACI in the rivaroxaban group (15.6% [10 of 64 patients]) were similar to those in the warfarin group (15.9% [10 of 63 patients]; p = 1.000). No thromboembolic events developed; no differences in major or nonmajor bleeding rates were observed between the 2 drug groups (3.1% vs. 1.6%, respectively, or 18.8% vs. 19.0%, respectively). Multiple regression analysis indicated that the presence of deep and subcortical white matter hyperintensity (p = 0.002; odds ratio [OR]: 5.323) and the frequency of cardioversions (p = 0.016; OR: 1.250) were associated with the incidence of ACI.

CONCLUSIONS

No notable differences were found between the incidence of CA-induced ACI in the rivaroxaban group and that in the warfarin group in this randomized study.

Periprocedural management of anticoagulation for atrial fibrillation catheter ablation in direct oral anticoagulant-treated patients

BACKGROUND

Guidelines recommend performing atrial fibrillation (AF) catheter ablation without interruption of a direct oral anticoagulants (DOACs) and to administer unfractionated heparin (UFH) for an activated clotting time (ACT) ≥300 seconds, by analogy with vitamin K antagonist (VKA). Nevertheless, pharmacological differences between DOACs and VKA, especially regarding ACT sensitivity and UFH response, prevent extrapolation from VKA to DOACs.

HYPOTHESIS

The level of anticoagulation at the time of the procedure in uninterrupted DOAC-treated patients is unpredictable and would complicate intraprocedural UFH administration and monitoring.

METHODS

This prospective study included interrupted DOAC-treated patients requiring AF ablation. Preprocedural DOAC concentration ([DOAC]), intraprocedural UFH administration, and ACT values were recorded. A cohort of DOAC-treated patients requiring flutter catheter ablation was considered to illustrate [DOAC] without DOAC interruption.

RESULTS

Forty-eight patients underwent AF and 14 patients underwent flutter ablation, respectively. In uninterrupted DOAC-treated patients, [DOAC] ranged from ≤30 to 466 ng/mL. When DOAC were interrupted, from 54 to 218 hours, [DOAC] were minimal (maximum: 36 ng/mL), preventing DOAC-ACT interference. Anyway, ACT values were poorly correlated with UFH doses (R ²  = 0.2256).

CONCLUSIONS

Our data showed that uninterrupted DOAC therapy resulted in an unpredictable and highly variable initial level of anticoagulation before catheter ablation. Moreover, even with DOAC interruption preventing interference between DOAC, UFH, and ACT, intraprocedural UFH monitoring was complex. Altogether, our exploratory results call into question the appropriateness of transposing UFH dose protocols, as well as the relevance of ACT monitoring in uninterrupted DOAC-treated patients.

Efficacy and safety of uninterrupted low-intensity warfarin for cryoballoon ablation of atrial fibrillation in the elderly: A pilot study

WHAT IS KNOWN AND OBJECTIVE

Uninterrupted warfarin during cryoballoon ablation (CB-A) of atrial fibrillation (AF) has been widely accepted. However, to our knowledge, no previous studies exist investigating the optimal intensity of anticoagulation with warfarin for CB-A. This study aimed to evaluate the efficacy and safety of uninterrupted low-intensity warfarin for CB-A of AF in the elderly.

METHODS

Paroxysmal AF patients (age ≥ 70 years) who underwent CB-A were enrolled prospectively. The participants were stratified into 2 groups based on international normalized ratio (INR) before ablation (INR in group A: 1.5 to 2.0; INR in group B: 2.0-2.5). Primary endpoints included periprocedural thromboembolic complications and major bleeding. Secondary endpoints were new asymptomatic cerebral emboli (ACE) and minor bleeding.

RESULTS AND DISCUSSION

A total of 144 patients were enrolled (group A: 65; group B: 79). In group A, the use of concomitant antiplatelet drugs was more common. Also, the mean HAS-BLED score was significantly higher (2.4 ± 0.8 vs 2.0 ± 0.6, P < .01) and the mean activated clotting time (ACT) during the procedure was significantly lower (302 ± 14 s vs 311 ± 11 s, P < .01). Other clinical characteristics were balanced between the 2 groups. No thromboembolic complications and major bleeding occurred in either group. The incidence of periprocedural ACE was comparable between the 2 groups (9.2% vs 6.3%, P = .74). The incidence of minor bleeding in group A and group B was 4.6% and 11.4%, respectively (P = .14).

WHAT IS NEW AND CONCLUSION

Compared with standard-intensity warfarin, uninterrupted low-intensity warfarin might not increase the incidence of thromboembolic complications and might be associated with less bleeding risk during the perioperative period of cryoballoon ablation in the elderly. Large trials are needed to confirm these results.

REduction of THRomboembolic EVents during Ablation using the laserballoon: The RETHREVA registry

INTRODUCTION

Cerebral events (CEs), including silent (SCEs), are a known complication of left atrial catheter ablation (LACA) in patients with atrial fibrillation. The aim of this prospective registry was to gain more information about CEs during laserballoon LACA and to reduce the risk of their occurrence.

METHODS AND RESULTS

We enrolled 74 patients (age 61 ± 11 years; 74% male; CHA₂ DS₂ -VASc 1.9 ± 1.4). Cerebral MRI (1.5 Tesla) was performed to detect CEs. ASPItest identified aspirin-resistant patients (ARPs). All bleeding complications were recorded. Due to an initial high CE rate, we evolved our clinical procedure step-by-step arriving at an optimized protocol: -Group 1: heparin after single transseptal puncture (TP), activated clotting time (ACT) > 300 seconds (CE: 64.3%). -Group 2: heparin after double TP, ACT > 300 seconds; 2a without (CE: 45.5%, RRR: -29.2%) and 2b with additional intravenous aspirin (CE: 36.4%, RRR: -43.4%; excluding ARP: 30%, RRR: -53.3%). -Group 3: heparin before double TP, ACT > 350 seconds; 3a without (CE: 54.5%, RRR: -15.2%) and 3b with aspirin (CE: 18.5%, RRR: -71.2%; excluding ARP: 8.7%, RRR: -86.5%). Larger LA diameter > 44 mm (OR: 1.149, P  =  0.005) and no aspirin use (OR: 4.308, P  =  0.008) were CE risk factors in multivariate logistic regression. In those patients receiving aspirin, aspirin resistance (OR: 22.4, P  =  0.011) was an exceptionally strong risk factor.

CONCLUSION

These data support the use of intravenous aspirin including monitoring of aspirin resistance in addition to ACT-guided heparin. An optimized protocol of heparin before TP, double TP, and intravenous aspirin in non-ARP resulted in a significantly lowered CE incidence and severity.

The Impact of Advances in Atrial Fibrillation Ablation Devices on the Incidence and Prevention of Complications

The number of patients with atrial fibrillation currently referred for catheter ablation is increasing. However, the number of trained operators and the capacity of many electrophysiology labs are limited. Accordingly, a steeper learning curve and technical advances for efficient and safe ablation are desirable. During the last decades several catheter-based ablation devices have been developed and adapted to improve not only lesion durability, but also safety profiles, to shorten procedure time and to reduce radiation exposure. The goal of this review is to summarise the reported incidence of complications, considering device-related specific aspects for point-by-point, multi-electrode and balloon-based devices for pulmonary vein isolation. Recent technical and procedural developments aimed at reducing procedural risks and complications rates will be reviewed. In addition, the impact of technical advances on procedural outcome, procedural length and radiation exposure will be discussed.

Pulmonary Vein Isolation with the Multipolar nMARQ™ Ablation Catheter: Efficacy And Safety In Acute And Long-Term Follow Up

Pulmonary vein isolation (PVI) is an established therapy for atrial fibrillation (AF). One challenge in the catheter-based treatment of this arrhythmia is to develop an effective and safe ablation approach to achieve durable and consistent lesions around the PVs. The multipolar irrigated radiofrequency (RF) ablation catheter nMARQ^TM was designed as a single-shot device with the aim to achieve these goals. This article reviews the current literature with respect to acute- and long- term success rates after PVI with this circular mapping and ablation device. Furthermore, since this device recently became discredited to potential lethal complications, we will also focus on the data available on safety issues with this ablation system.

Five-year impact of catheter ablation for atrial fibrillation in patients with a prior history of stroke

BACKGROUND

Catheter ablation of atrial fibrillation (AF) is an established therapeutic rhythm approach. Patients with a prior history of a stroke (CVA) represent a unique high-risk population for recurrent thromboembolic events. The role of antiarrhythmic treatment on the natural history of stroke recurrence in these patients is not fully understood.

METHODS

Three patient groups with a prior CVA and 5 years of follow-up were matched 1:3:3 by propensity score (±0.01): AF ablation patients receiving their first ablation (n  =  139), AF patients that did not receive an ablation (n  =  416), and CVA patients without clinical AF (n  =  416). Prior CVA was determined by medical chart review. Patients were followed for outcomes of recurrent CVA, heart failure, and death.

RESULTS

The average age of the population was 69 ± 11 years and 51% male. AF ablation patients had higher rates of hypertension and heart failure (P < 0.0001), but diabetes prevalence was similar between the groups (P  =  0.5). Note that 5-year risk of CVA (HR  =  2.26, P < 0.0001) and death (HR  =  2.43, P < 0.0001) were higher in the AF, no ablation group compared those that were ablated. When comparing AF, ablation to no AF patients, there was not a significant difference in 5-year risk of for CVA (HR  =  0.82, P  =  0.39) and death (HR  =  0.92, P  =  0.70); however, heart failure risk was increased (HR  =  3.08, P  =  0.001).

CONCLUSION

In patients with AF and a prior CVA, patients undergoing ablation have lower rates of recurrent stroke compared to AF patients not ablated. Although the full mechanisms of benefit are unknown, as CVA rates are similar to patients without AF these data are suggestive of a potential altering of the natural history of disease progression.

Recognizing and reacting to complications of trans-septal puncture

INTRODUCTION

The transseptal puncture (TSP) enables access to the left heart, through the fossa ovalis (FO), both in electrophysiology and in cardiac interventional procedures. TSP is usually safe in experienced hands. Sometimes TSP can be technically demanding and carries the risk of severe complications in approximately 1%. While performing a TSP, every effort should be taken in order to avoid complications. In the event of complications, prompt recognition and reaction are essential and a combined 'heart-team' management may be the most effective approach. Areas covered: Main TSP-related complications are cardiac tamponade, aortic root puncture, embolic stroke, transient ST elevation of inferior leads and iatrogenic atrial septal defect. A challenging TSP may be expected in presence of difficult IAS-FO anatomies, previous TSP, IAS occluder device and previous IAS surgical repair. Use of echo imaging and special needles (ie., radiofrequency needle and J-shaped guidewire) may avoid TSP-related complications in difficult settings. Expert commentary: Some tools are available to help minimize the risks of TSP. However, their availability might be limited. To increase safety of TSP, an adequate training of physicians, identification of patients in whom it might be difficult and a prompt recognition of complications seem to be the most important background.