When anticoagulation management in atrial fibrillation becomes difficult: Focus on chronic kidney disease, coagulation disorders, and cancer

Anticoagulation therapy (AT) is fundamental in atrial fibrillation (AF) treatment but poses challenges in implementation, especially in AF populations with elevated thromboembolic and bleeding risks. Current guidelines emphasize the need to estimate and balance thrombosis and bleeding risks for all potential candidates of antithrombotic therapy. However, administering oral AT raises concerns in specific populations, such as those with chronic kidney disease (CKD), coagulation disorders, and cancer due to lack of robust data. These groups, excluded from large direct oral anticoagulants trials, rely on observational studies, prompting physicians to adopt individualized management strategies based on case-specific evaluations. The scarcity of evidence and specific guidelines underline the need for a tailored approach, emphasizing regular reassessment of risk factors and anticoagulation drug doses. This narrative review aims to summarize evidence and recommendations for challenging AF clinical scenarios, particularly in the long-term management of AT for patients with CKD, coagulation disorders, and cancer.

Durability of Thermal Pulmonary Vein Isolation in Persistent Atrial Fibrillation Assessed by Mandated Repeat Invasive Study

BACKGROUND

No study has assessed durability of pulmonary vein isolation (PVI) with radiofrequency (RF) and Cryoballoon (CB) in patients with persistent AF. These data are especially lacking for those with significantly diseased left atria (LA).

OBJECTIVE

To assess PVI durability in patients with significant LA disease and compare reconnection rates between RF and CB.

METHODS

44 Patients (mean age 63, 77% male, median time since AF diagnosis 22.5 months, median indexed LA volume 36 ml/m2) were randomised 1:1 to RF (StablePoint catheter, Boston Scientific) or CB (Arctic Front Advance, Medtronic) PVI. A redo procedure using ultra high-density electroanatomic mapping (Rhythmia, Boston Scientific) was mandated at 2 months, where PV reconnections were identified and re-isolated.

RESULTS

38 patients underwent both procedures (n=17 CB, n=21 RF). Index RF procedures were longer (median 158 vs 97min; p<0.001) but required less fluoroscopy (9.5 vs 23min; p<0.001). At the index RF procedure, median 47% of LA myocardium had voltage <0.5mV, suggesting half of the mapped LA comprised scar. PV reconnection was observed in 73/152 (48.0%) PVs and was more frequent with CB (58.8%) vs RF (39.3%), p=0.022. Reconnection of at least 1 PV was detected in >75% of patients. Significantly more ablation was required at redo to reisolate PVs in the CB arm (median 10.8 vs 1.2min; p<0.001).

CONCLUSION

PVI durability may be poor in those with significant LA scarring and dilatation, even with modern thermal ablation technologies. RF resulted in significantly better PVI durability than CB in this complex population.

CLINICAL TRIAL REGISTRATION

NCT04111731.

Lesion metrics and 12-month outcomes of very-high power short duration radiofrequency ablation (90W/4 s) under mild conscious sedation

INTRODUCTION

Pulmonary vein isolation (PVI) is often performed under general anaesthesia (GA) or deep sedation. Anaesthetic availability is limited in many centers, and deep sedation is prohibited in some countries without anaesthetic support. Very high-power short duration (vHPSD-90W/4 s) PVI using the Q-Dot catheter is generally well tolerated under mild conscious sedation (MCS) though an understanding of catheter stability and long-term effectiveness is lacking. We analyzed lesion metrics and 12-month freedom from atrial arrythmia with this approach.

METHODS

Our approach to radiofrequency (RF) PVI under MCS is standardized and includes a single catheter approach with a steerable sheath. We identified patients undergoing Q-Dot RF PVI between March 2021 and December 2022 in our center, comparing those undergoing vHPSD ablation under MCS (90W/MCS) against those undergoing 50 W ablation under GA (50 W/GA) up to 12 months of follow-up. Data were extracted from clinical records and the CARTO system.

RESULTS

Eighty-three patients met our inclusion criteria (51 90W/MCS; 32 50 W/GA). Despite shorter ablation times (353 vs. 886 s; p < .001), the 90 W/MCS group received more lesions (median 87 vs. 58, p < .001), resulting in similar procedure times (149.3 vs. 149.1 min; p = .981). PVI was achieved in all cases, and first pass isolation rates were similar (left wide antral circumferential ablation [WACA] 82.4% vs. 87.5%, p = .758; right WACA 74.5% vs. 78.1%, p = .796; 90 W/MCS vs. 50 W/GA respectively). Analysis of 6647 ablation lesions found similar mean impedance drops (10.0 ± 1.9 Ω vs. 10.0 ± 2.2 Ω; p = .989) and mean contact force (14.6 ± 2.0 g vs. 15.1 ± 1.6 g; p = .248). Only median 2.5% of lesions in the 90 W/MCS cohort failed to achieve ≥ 5 Ω drop. In the 90 W/MCS group, there were no procedural related complications, and 12-month freedom from atrial arrhythmia was observed in 78.4%.

CONCLUSION

vHPSD PVI is feasible under MCS, with encouraging acute and long-term procedural outcomes. This provides a compelling option for centers with limited anaesthetic support.

Predicting stroke in Asian patients with atrial fibrillation using machine learning: A report from the KERALA-AF registry, with external validation in the APHRS-AF registry

Atrial fibrillation (AF) is a significant risk factor for stroke. Based on the higher stroke associated with AF in the South Asian population, we constructed a one-year stroke prediction model using machine learning (ML) methods in KERALA-AF South Asian cohort. External validation was performed in the prospective APHRS-AF registry. We studied 2101 patients and 83 were to patients with stroke in KERALA-AF registry. The random forest showed the best predictive performance in the internal validation with receiver operator characteristic curve (AUC) and G-mean of 0.821 and 0.427, respectively. In the external validation, the light gradient boosting machine showed the best predictive performance with AUC and G-mean of 0.670 and 0.083, respectively. We report the first demonstration of ML's applicability in an Indian prospective cohort, although the more modest prediction on external validation in a separate multinational Asian registry suggests the need for ethnic-specific ML models.

Relationship of Warfarin and Apixaban with Vascular Function in Patients with Atrial Fibrillation

INTRODUCTION

Atrial fibrillation (AF) is associated with endothelial damage/dysfunction. Herein, we tested the hypothesis that brachial artery flow-mediated dilation (FMD) is superior in AF patients taking apixaban compared to warfarin.

METHODS

AF patients on apixaban (n = 46; 67 [7] years; mean [standard deviation]; 15 women) and warfarin (n = 27; 73 [9] years (p < 0.01); 11 women) were recruited. Duplex Doppler ultrasound imaging was undertaken during baseline (2 min), cuff inflation (5 min), and following cuff deflation (3 min). FMD was defined as peak increase in brachial artery diameter following cuff deflation and analysed as percentage change in diameter, as a ratio of FMD, shear rate area under the curve (SRAUC; FMD-to-SRAUC), and using SRAUC as a covariate (FMDSR).

RESULTS

Baseline artery diameter (4.96 [1.14] vs. 4.89 [0.88] mm), peak diameter (5.12 [1.17] vs. 5.14 [0.93] mm), and FMDSR (3.89 [3.62] vs. 4.80 [3.60] %) were not different between warfarin and apixaban (p > 0.05; analysis of covariance with age, CHA2DS2-VASc, years since AF diagnosis, number of diabetics, alcohol drinkers, and units of alcohol consumed per week as covariates). Stepwise multiple regression identified independent association of fibrillation, hypertension, and increased age with FMD.

CONCLUSION

AF patients on warfarin and apixaban exhibit similar endothelium-dependent vasodilation. Increased blood pressure negatively impacts vasodilator capacity in AF patients.

Left Atrial Appendage Occlusion: British Cardiovascular Intervention Society and British Heart Rhythm Society Position Statement

Percutaneous left atrial appendage occlusion aims to reduce the risk of stroke in patients with AF, particularly those who are not good candidates for systemic anticoagulation. The procedure has been studied in large international randomised trials and registries and was approved by the National Institute for Health and Care Excellence in 2014 and by NHS England in 2018. This position statement summarises the evidence for left atrial appendage occlusion and presents the current indications. The options and consensus on best practice for pre-procedure planning, undertaking a safe and effective implant and appropriate post-procedure management and follow-up are described. Standards regarding procedure volume for implant centres and physicians, the role of multidisciplinary teams and audits are highlighted.

Feasibility of double-blinded, placebo-controlled interventional study for assessing catheter ablation efficacy in persistent atrial fibrillation: Insights from the ORBITA AF feasibility study

BACKGROUND

To date, there are no randomized, double-blinded clinical trials comparing catheter ablation to DC cardioversion (DCCV) with medical therapy in patients with persistent atrial fibrillation (PersAF). Conducting a large-scale trial to address this question presents considerable challenges, including recruitment, blinding, and implementation. We conducted a pilot study to evaluate the feasibility of conducting a definitive placebo-controlled trial.

METHODS

This prospective trial was carried out at Barts Heart Centre, United Kingdom, employing a randomized, double-blinded, placebo-controlled design. Twenty patients with PersAF (duration <2 years) were recruited, representing 10% of the proposed larger trial as determined by a power calculation. The patients were randomized in a 1:1 ratio to receive either PVI ± DCCV (PVI group) or DCCV + Placebo (DCCV group). The primary endpoint of this feasibility study was to evaluate patient blinding. Patients remained unaware of their treatment allocation until end of study.

RESULTS

During the study, 35% of patients experienced recurrence of PersAF prior to completion of 12 months follow-up. Blinding was successfully maintained amongst both patients and medical staff. The DCCV group had a trend to higher recurrence and repeat procedure rate compared to the PVI group (recurrence of PersAF 60% vs 30%; p = .07 and repeat procedure 70% vs 40%; p = .4). The quality of life experienced by individuals in the PVI group showed improvement, as evidenced by enhanced scores on the AF specific questionnaire (AF PROMS) (3 [±4] vs 21 [±8]) and SF-12 mental-component raw score (51.4 [±7] vs 43.24 [±15]) in patients who maintained sinus rhythm at 12 months.

CONCLUSION

This feasibility study establishes the potential for conducting a blinded, placebo-controlled trial to evaluate the efficacy of PVI versus DCCV in patients with PersAF.

Novel stroke prevention strategies following catheter ablation for atrial fibrillation

Stroke prevention following successful catheter ablation of atrial fibrillation remains a controversial topic. Oral anticoagulation is associated with a significant reduction in stroke risk in the general atrial fibrillation population but may be associated with an increased risk of major bleeding, and the benefit: risk ratio must be considered. Improvement in successful catheter ablation and widespread use of cardiac monitoring devices may allow for novel anticoagulation strategies in a subset of patients with atrial fibrillation, which may optimize stroke prevention while minimizing bleeding risk. In this review, we discuss stroke risk in atrial fibrillation and the effects of successful catheter ablation on thromboembolic risk. We also explore novel strategies for stroke prevention following successful catheter ablation.

Embolization of percutaneous left atrial appendage closure devices: timing, management and clinical outcomes

BACKGROUND

Left atrial appendage (LAA) occluder embolization is an infrequent but serious complication.

OBJECTIVES

We aim to describe timing, management and clinical outcomes of device embolization in a multi-center registry.

METHODS

Patient characteristics, imaging findings and procedure and follow-up data were collected retrospectively. Device embolizations were categorized according to 1) timing 2) management and 3) clinical outcomes.

RESULTS

Sixty-seven centers contributed data. Device embolization occurred in 108 patients. In 70.4 % of cases, it happened within the first 24 h of the procedure. The device was purposefully left in the LA and the aorta in two (1.9 %) patients, an initial percutaneous retrieval was attempted in 81 (75.0 %) and surgery without prior percutaneous retrieval attempt was performed in 23 (21.3 %) patients. Two patients died before a retrieval attempt could be made. In 28/81 (34.6 %) patients with an initial percutaneous retrieval attempt a second, additional attempt was performed, which was associated with a high mortality (death in patients with one attempt: 2.9 % vs. second attempt: 21.4 %, p < 0.001). The primary outcome (bailout surgery, cardiogenic shock, stroke, TIA, and/or death) occurred in 47 (43.5 %) patients. Other major complications related to device embolization occurred in 21 (19.4 %) patients.

CONCLUSIONS

The majority of device embolizations after LAA closure occurs early. A percutaneous approach is often the preferred method for a first rescue attempt. Major adverse event rates, including death, are high particularly if the first retrieval attempt was unsuccessful.

CONDENSED ABSTRACT

This dedicated multicenter registry examined timing, management, and clinical outcome of device embolization. Early embolization (70.4 %) was most frequent. As a first rescue attempt, percutaneous retrieval was preferred in 75.0 %, followed by surgical removal (21.3 %). In patients with a second retrieval attempt a higher mortality (death first attempt: 2.9 % vs. death second attempt: 24.1 %, p < 0.001) was observed. Mortality (10.2 %) and the major complication rate after device embolization were high.

Left Atrial Appendage Occlusion Versus Direct Oral Anticoagulants in the Prevention of Ischaemic Stroke in Patients with Atrial Fibrillation

Introduction Existing randomised controlled trials assessing the safety and efficacy of left atrial appendage occlusion (LAAO) in atrial fibrillation (AF) were of relatively small sample size, or included patients who could receive oral anticoagulant treatment after device implantation. We compared the outcomes of patients with newly diagnosed AF who received percutaneous LAAO or direct oral anticoagulants (DOAC) treatment, in a large population from a global federated health network (TriNetX). Methods Patients with AF treated with percutaneous LAAO were matched with those treated with DOAC between 1st December 2010 and 1st October 2018. Outcomes were all-cause mortality, ischaemic stroke and intracranial haemorrhage (ICH) at 5 years. Results We included 200 patients with AF, who received either LAAO or DOAC. The risk of all-cause mortality, ischaemic stroke and ICH at 5 years was not significantly different between the two groups (Risk Ratio [RR] for all-cause mortality: 1.52, 95% confidence interval (CI): 0.97- 2.38, RR for ischaemic stroke: 1.09, 95% CI: 0.51- 2.36, and RR for ICH: 1.0, 95% CI: 0.44- 2.30). Conclusion Patients newly diagnosed with AF, eligible for DOAC, showed similar 5-year risk of death, ischemic stroke, and ICH when comparing those who underwent percutaneous LAAO to those receiving DOAC. Future randomised controlled trials are needed to confirm the findings and advise changes in guidelines.

Atrial fibrillation: better symptom control with rate and rhythm management

Atrial fibrillation (AF) is often associated with limiting symptoms, and with significant impairment in quality of life. As such, treatment strategies aimed at symptom control form an important pillar of AF management. Such treatments include a wide variety of drugs and interventions, including, increasingly, catheter ablation. These strategies can be utilised either singly or in combination, to improve and restore quality of life for patients, and this review covers the current evidence base underpinning their use. In this Review, we discuss the pros and cons of rate vs. rhythm control, while offering practical tips to non-specialists on how to utilise various treatments and counsel patients about all relevant treatment options. These include antiarrhythmic and rate control medications, as well as interventions such as cardioversion, catheter ablation, and pace-and-ablate.

Silent pulmonary veins at redo ablation for atrial fibrillation: Implications and approaches

BACKGROUND

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Despite promising success rates, redo ablation is sometimes required. At redo, PVs may be found to be isolated (silent) or reconnected. We studied patients with silent vs reconnected PVs at redo and analysed associations with adverse outcomes.

METHODS

Patients undergoing redo AF ablations between 2013 and 2019 at our institution were included and stratified into silent PVs or reconnected PVs. The primary outcome was a composite of further redo ablation, non-AF ablation, atrioventricular nodal ablation, and death. Secondary outcomes included arrhythmia recurrence.

RESULTS

A total of 467 patients were included with mean 4.6 ± 1.7 years follow-up, of whom 48 (10.3%) had silent PVs. The silent PV group had had more often undergone >1 prior ablation (45.8% vs 9.8%; p<0.001), had more persistent AF (62.5% vs 41.1%; p=0.005) and had more non-PV ablation performed both at prior ablation procedures and at the analysed redo ablation. The primary outcome occurred more frequently in those with silent PVs (25% vs 13.8%; p=0.053). Arrhythmia recurrence was also more common in the silent PV group (66.7% vs 50.6%; p=0.047). After multivariable adjustment, female sex (aHR 2.35 [95% CI 2.35-3.96]; p=0.001) and ischaemic heart disease (aHR 3.21 [95% CI 1.56-6.62]; p=0.002) were independently associated with the primary outcome, and left atrial enlargement (aHR 1.58 [95% CI 1.20-2.08]; p=0.001) and >1 prior ablation (aHR 1.88 [95% CI 1.30-2.72]; p<0.001) were independently associated with arrhythmia recurrence. Whilst a finding of silent PVs was not itself significant after multivariable adjustment, this provides an easily assessable parameter at clinically indicated redo ablation which informs the clinician of the likelihood of a worse future prognosis.

CONCLUSIONS

Patients with silent PVs at redo AF ablation have worse clinical outcomes.

Persistent and Recurrent Device-Related Thrombus After Left Atrial Appendage Closure: Incidence, Predictors, and Outcomes

BACKGROUND

Scarce data exist on the evolution of device-related thrombus (DRT) after left atrial appendage closure (LAAC).

OBJECTIVES

This study sought to assess the incidence, predictors, and clinical impact of persistent and recurrent DRT in LAAC recipients.

METHODS

Data were obtained from an international multicenter registry including 237 patients diagnosed with DRT after LAAC. Of these, 214 patients with a subsequent imaging examination after the initial diagnosis of DRT were included. Unfavorable evolution of DRT was defined as either persisting or recurrent DRT.

RESULTS

DRT resolved in 153 (71.5%) cases and persisted in 61 (28.5%) cases. Larger DRT size (OR per 1-mm increase: 1.08; 95% CI: 1.02-1.15; P = 0.009) and female (OR: 2.44; 95% CI: 1.12-5.26; P = 0.02) were independently associated with persistent DRT. After DRT resolution, 82 (53.6%) of 153 patients had repeated device imaging, with 14 (17.1%) cases diagnosed with recurrent DRT. Overall, 75 (35.0%) patients had unfavorable evolution of DRT, and the sole predictor was average thrombus size at initial diagnosis (OR per 1-mm increase: 1.09; 95% CI: 1.03-1.16; P = 0.003), with an optimal cutoff size of 7 mm (OR: 2.51; 95% CI: 1.39-4.52; P = 0.002). Unfavorable evolution of DRT was associated with a higher rate of thromboembolic events compared with resolved DRT (26.7% vs 15.1%; HR: 2.13; 95% CI: 1.15-3.94; P = 0.02).

CONCLUSIONS

About one-third of DRT events had an unfavorable evolution (either persisting or recurring), with a larger initial thrombus size (particularly >7 mm) portending an increased risk. Unfavorable evolution of DRT was associated with a 2-fold higher risk of thromboembolic events compared with resolved DRT.

Concurrent percutaneous left atrial appendage occlusion and catheter ablation for atrial fibrillation: State-of-the-art review

Stroke prevention and symptom control are two integral pillars in atrial fibrillation (AF) management. Percutaneous left atrial appendage occlusion (LAAO) is effective at reducing stroke risk in high-risk patients with AF who cannot tolerate oral anticoagulant therapy, whilst catheter ablation is effective at reducing AF burden and improving quality-of-life in patients who remain symptomatic despite medical therapy. If both procedures are indicated in an individual patient, they have traditionally been performed on separate occasions, due to long cumulative procedural times, itself associated with thromboembolic risk. Recently, with the advancement of procedural techniques, the concept of concurrent LAAO and AF catheter ablation has gained traction. This review summarises the evidence for and against concurrent LAAO and AF catheter ablation, discussing procedural considerations, including procedural sequencing and post-procedural antithrombotic therapy, safety and efficacy outcomes, and future directions in the field.

Incidence and predictors of stroke and silent cerebral embolism following very high-power short-duration atrial fibrillation ablation

AIMS

Cerebral thrombo-embolism is a dreaded complication of pulmonary vein isolation (PVI) for atrial fibrillation; its surrogate, silent cerebral embolism (SCE) can be detected by diffusion-weighted brain magnetic resonance imaging (bMRI). Initial investigations have raised a concern that very high-power, short-duration (vHPSD; 90 W/4 s) temperature-controlled PVI with the QDOT Micro catheter may be associated with a higher incidence of SCE compared with low-power long-duration ablation. We aimed to assess the incidence of procedural complications of vHPSD PVI with an emphasis on cerebral safety.

METHODS AND RESULTS

We enrolled 328 consecutive patients undergoing their PVI procedure using vHPSD. A subgroup of 61 consecutive patients underwent diffusion-weighted bMRI within 24 h of the procedure, and incidence and predictors of SCE were studied. The mean procedure time and left atrial dwell time for the overall cohort were 69.6 ± 24.1 and 46.5 ± 21.5 min, respectively. First-pass isolation was achieved in 82%. No stroke or transient ischaemic attack occurred. Silent cerebral embolism was identified in 5 of 61 patients (8.2%). Silent cerebral embolism following procedures was significantly associated with lower baseline generator impedance (105.8 vs. 112.6 Ω, P < 0.0001) and with intermittent loss of catheter-tissue contact during ablation (14.1% vs. 6.1%, P < 0.0001).

CONCLUSION

Very high-power, short-duration PVI is a safe technique with an excellent acute success rate. Silent cerebral embolism incidence in our cohort was below the previously reported range, with no clinically overt cerebral complications. Lower baseline generator impedance and loss of contact during ablation may contribute to a higher risk of SCEs.

Radiofrequency catheter ablation of atrial fibrillation: A review of techniques

Ablation of atrial fibrillation is a key area of current research. A multitude of techniques have been tested, some of which are poorly evidenced and not recommended in routine clinical practice whilst others are more promising. Additionally, a plethora of issues exist when researching ablation techniques, from control arm ablation strategy to the relevance of outcome measures. In this review article, we discuss these issues in the context of the current evidence base.

Ripple AT Plus - isthmus-guided vs conventional ablation in the treatment of scar-related atrial tachycardia: study protocol for a randomised controlled trial

BACKGROUND

Catheter ablation is routinely used to treat scar-related atrial tachycardia (s-AT). Conventional ablation often involves creating anatomical "lines" that transect myocardial tissue supporting reentry. This can be extensive, creating iatrogenic scar as a nidus for future reentry, and may account for arrhythmia recurrence. High-density mapping may identify "narrower isthmuses" requiring less ablation, with ripple mapping proven to be an effective approach in identifying. This trial explores whether ablation of narrower isthmuses in s-AT, defined using ripple mapping, results in greater freedom from arrhythmia recurrence compared to conventional ablation.

METHODS

The Ripple-AT-Plus trial (registration ClinicalTrials.gov , NCT03915691) is a prospective, multicentre, single-blinded, randomised controlled trial with 12-month follow-up. Two hundred s-AT patients will be randomised in a 1:1 fashion to either "ripple mapping-guided isthmus ablation" vs conventional ablation on the CARTO3 ConfiDENSE system (Biosense Webster). The primary outcome will compare recurrence of any atrial arrhythmia. Multicentre data will be analysed over a secure web-based cloud-storage and analysis software (CARTONETTM).

CONCLUSION

This is the first trial that considers long-term patient outcomes post s-AT ablation, and whether targeting narrower isthmuses in the era of high density is optimal.

Social determinants of health and recurrence of atrial fibrillation after catheter ablation: a Danish nationwide cohort study

AIMS

To examine the associations between three social determinants of health (SDOH) and recurrence of AF after ablation.

METHODS AND RESULTS

We selected patients who underwent a first ablation after an incident hospital diagnosis of AF between 2005 and 2018 from the entire Danish population. Educational attainment, family income, and whether the patient was living alone were assessed at the time of ablation. We used cause-specific proportional hazard models to estimate hazard ratios (HR) with 95% confidence interval (CI) adjusted for age and sex. In secondary analyses, we adjusted for comorbidities, antiarrhythmic medication, and prior electrical cardioversion.We selected 9728 patients (mean age 61 years, 70% men), and 5881 patients had AF recurrence over an average of 1.37 years after ablation (recurrence rate 325.7 (95% CI 317.6-334.2) per 1000 person-years). Lower education (HR 1.09 [1.02-1.17] and 1.07 [1.01-1.14] for lower and medium vs. higher), lower income [HR 1.14 (1.06-1.22) and 1.09 (1.03-1.17) for lower and medium vs. higher], and living alone [HR 1.07 (1.00-1.13)] were associated with increased rates of recurrence of AF. We found no evidence of interaction between sex or prior HF with SDOH. The association between family income and AF recurrence was stronger among patients < 65 years compared with those aged ≥ 65 years. The associations between SDOH and AF recurrence did not persist in the multivariable model.

CONCLUSION

AF was more likely to recur among patients with lower educational attainment, lower family income, or those living alone. Multidisciplinary efforts are needed to reduce socioeconomic inequity in the effect of ablation.

Sex Differences in Atrial Fibrillation

PURPOSE OF REVIEW

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The estimated lifetime risk of developing AF is higher in men; however, due to differences in life expectancy, the overall prevalence is higher among women, particularly in the older age group. Sex differences play an important role in the pathophysiology, presentation, and clinical outcomes of AF. Awareness of these differences minimizes the potential for disparities in AF management. Our review summarizes the current literature on sex differences in AF, including the epidemiology, pathophysiology, risk factors, clinical symptomatology, mechanisms, treatment, and outcomes. We also explore the implications of these differences for clinical practice and future research.

RECENT FINDINGS

Women are more likely to present with atypical symptoms, have a higher stroke risk, and have a worse quality of life with AF when compared to men. Despite this, they are less likely to receive rhythm control strategies and anticoagulants. The sex-based differences in AF pathology and management might be a combination of inherent biological and hormonal differences, and implicit bias of the research entities and treating clinicians. Our review stresses the need for further sex-specific research in the pathophysiology of AF and opens a dialogue on personalized medicine, where management strategies can be tailored to individual patient characteristics, including sex.

Atrial fibrillation and stroke prevention: 25 years of research at EP Europace journal

Stroke prevention in patients with atrial fibrillation (AF) is one pillar of the management of this common arrhythmia. Substantial advances in the epidemiology and associated pathophysiology underlying AF-related stroke and thrombo-embolism are evident. Furthermore, the introduction of the non-vitamin K antagonist oral anticoagulants (also called direct oral anticoagulants) has clearly changed our approach to stroke prevention in AF, such that the default should be to offer oral anticoagulation for stroke prevention, unless the patient is at low risk. A strategy of early rhythm control is also beneficial in reducing strokes in selected patients with recent onset AF, when compared to rate control. Cardiovascular risk factor management, with optimization of comorbidities and attention to lifestyle factors, and the patient's psychological morbidity are also essential. Finally, in selected patients with absolute contraindications to long-term oral anticoagulation, left atrial appendage occlusion or exclusion may be considered. The aim of this state-of-the-art review article is to provide an overview of the current status of AF-related stroke and prevention strategies. A holistic or integrated care approach to AF management is recommended to minimize the risk of stroke in patients with AF, based on the evidence-based Atrial fibrillation Better Care (ABC) pathway, as follows: A: Avoid stroke with Anticoagulation; B: Better patient-centred, symptom-directed decisions on rate or rhythm control; C: Cardiovascular risk factor and comorbidity optimization, including lifestyle changes.

Outcomes of Atrioventricular Node Ablation and Pacing in Patients with Heart Failure and Atrial Fibrillation: From Cardiac Resynchronization Therapy to His Bundle Pacing

Objective: To review the relevant literature on the use of atrioventricular node ablation and pacing in patients with heart failure and atrial fibrillation. Methods: APubMed/MEDLINE and SCOPUS search was performed in order to assess the clinical outcomes of atrioventricular node ablation and pacemaker implantation, as well as the complications that may occur. Results: Several clinical trials, observational analyses and meta-analyses have shown that the "pace and ablate" strategy not only improves symptoms but also can enhance cardiac performance in patients with heart failure and atrial fibrillation. Although this procedure is effective and safe, some complications may occur including worsening of heart failure, permanent fibrillation, arrhythmias and sudden death. Regarding pacemaker implantation, cardiac resynchronization therapy is shown to be the optimal choice compared to right ventricle apical pacing. His bundle pacing is a promising alternative to cardiac resynchronization therapy and has shown beneficial effects, while left bundle branch pacing is an innovative modality. Conclusions: Atrioventricular node ablation and pacemaker implantation is shown to have beneficial effects on clinical outcomes of patients with atrial fibrillation ± heart failure who do not respond or are intolerant to medical treatment. Cardiac resynchronization therapy is the treatment of choice and His bundle pacing seems to be an effective alternative way of pacing in these patients.

Left Atrial Function Predicts Atrial Arrhythmia Recurrence Following Ablation of Long-Standing Persistent Atrial Fibrillation

BACKGROUND

Left atrial (LA) function following catheter or surgical ablation of de-novo long-standing persistent atrial fibrillation (AF) and its impact on AF recurrence was studied in patients participating in the CASA-AF trial (Catheter Ablation vs. Thoracoscopic Surgical Ablation in Long Standing Persistent Atrial Fibrillation).

METHODS

All patients underwent echocardiography preablation, 3 and 12 months post-ablation. LA structure and function were assessed by 2-dimensional volume and speckle tracking strain measurements of LA reservoir, conduit, and contractile strain. Left ventricular diastolic function was measured using transmitral Doppler filling velocities and myocardial tissue Doppler velocities to derive the e', E/e', and E/A ratios. Continuous rhythm monitoring was achieved using an implantable loop recorder.

RESULTS

Eighty-three patients had echocardiographic data suitable for analysis. Their mean age was 63.6±9.7 years, 73.5% were male, had AF for 22.8±11.6 months, and had a mean LA maximum volume of 48.8±13.8 mL/m². Thirty patients maintained sinus rhythm, and 53 developed AF recurrence. Ablation led to similar reductions in LA volumes at follow-up in both rhythm groups. However, higher LA emptying fraction (36.3±10.6% versus 27.9±9.9%; P<0.001), reservoir strain (22.6±8.5% versus 16.7±5.7%; P=0.001), and contractile strain (9.2±3.4% versus 5.6±2.5%; P<0.001) were noted in the sinus rhythm compared with AF recurrence group following ablation at 3 months. Diastolic function was better in the sinus rhythm compared with the AF recurrence group with an E/A ratio of 1.5±0.5 versus 2.2±1.2 (P<0.001) and left ventricular E/e' ratio of 8.0±2.1 versus 10.3±4.1 (P<0.001), respectively. LA contractile strain at 3 months was the only independent predictor of AF recurrence.

CONCLUSIONS

Following ablation for long-standing persistent AF, improvement in LA function was greater in those who maintained sinus rhythm. LA contractile strain at 3 months was the most important determinant of AF recurrence following ablation.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02755688.

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.

Left Atrial Appendage Occlusion-A Choice or a Last Resort? How to Approach the Patient

Left atrial appendage (LAA) occlusion is emerging as a viable alternative to oral anticoagulation in high-risk patients with atrial fibrillation. However, there remains limited evidence for this approach, especially in certain subgroups, and therefore patient selection is an important aspect of treatment. Here, the authors present arguments for LAA occlusion as either a last resort versus patient choice by evaluating contemporary studies on this topic and discuss practical steps in the approach of patients who may be suitable for LAA occlusion. Overall, an individualized and multidisciplinary team approach should be adopted in patients who are being considered for LAA occlusion.

Percutaneous Left Atrial Appendage Occlusion Following Successful Treatment of Large Bi-atrial Thrombi in a Patient with Atrial Fibrillation: A Case Report

Background

Atrial fibrillation (AF) is a well-established risk factor for intracardiac thrombosis. Left atrial appendage occlusion (LAAO) is emerging as a viable alternative to oral anticoagulation (OAC) for high-risk AF patients who are contraindicated to long term OAC.

Case Summary

A 74-year-old man with a history of permanent AF and subdural haemorrhage on warfarin therapy was referred to our facility for further management. Cardiac CT imaging revealed large bi-atrial thrombi for which apixaban therapy was initiated. Serial imaging over nine months showed gradual shrinkage and then resolution of the thrombi. In line with the patient’s preference to avoid life-long OAC, he received LAAO using an Amplatzer™ Amulet™ device. Follow-up transoesophageal echocardiography showed a well-seated device with no leak and no thrombus.

Discussion

We discussed the key issues surrounding management of bi-atrial thrombi and the decision to perform LAAO in these circumstances, relying on shared decision making and multi-disciplinary team input.

The neurocognitive effects of atrial fibrillation: benefits of the ABC pathway

Atrial fibrillation has a recognised association with not only stroke, but also neurocognitive impairment and both vascular and Alzheimer's dementia. Effective management of atrial fibrillation can reduce the risk of such complications. In this narrative review article, we discuss the pathophysiological links between atrial fibrillation and dementia, as well as the benefits of adherence to the guideline-recommended 'ABC' Pathway.

Racial and Ethnic Disparities in Stroke Prevention for Atrial Fibrillation

Racial and ethnic disparities in health care are well documented, although often underappreciated. In the setting of atrial fibrillation, stroke risk and severity may be higher in underrepresented ethnic populations. Additionally, the risk of bleeding is not uniform, and pharmacogenetics play an important role in anticoagulant therapy. In this narrative review, we discuss the complex issues surrounding stroke prevention in underrepresented ethnic groups with atrial fibrillation.

An approach to help differentiate postinfarct scar from borderzone tissue using Ripple Mapping during ventricular tachycardia ablation

BACKGROUND

Ventricular scar is traditionally highlighted on a bipolar voltage (BiVolt) map in areas of myocardium <0.50 mV. We describe an alternative approach using Ripple Mapping (RM) superimposed onto a BiVolt map to differentiate postinfarct scar from conducting borderzone (BZ) during ventricular tachycardia (VT) ablation.

METHODS

Fifteen consecutive patients (left ventricular ejection fraction 30 ± 7%) underwent endocardial left ventricle pentaray mapping (median 5148 points) and ablation targeting areas of late Ripple activation. BiVolt maps were studied offline at initial voltage of 0.50-0.50 mV to binarize the color display (red and purple). RMs were superimposed, and the BiVolt limits were sequentially reduced until only areas devoid of Ripple bars appeared red, defined as RM-scar. The surrounding area supporting conducting Ripple wavefronts in tissue <0.50 mV defined the RM-BZ.

RESULTS

RM-scar was significantly smaller than the traditional 0.50 mV cutoff (median 4% vs. 12% shell area, p < .001). 65 ± 16% of tissue <0.50 mV supported Ripple activation within the RM-BZ. The mean BiVolt threshold that differentiated RM-scar from BZ tissue was 0.22 ± 0.07 mV, though this ranged widely (from 0.12 to 0.35 mV). In this study, septal infarcts (7/15) were associated with more rapid VTs (282 vs. 347 ms, p = .001), and had a greater proportion of RM-BZ to RM-scar (median ratio 3.2 vs. 1.2, p = .013) with faster RM-BZ conduction speed (0.72 vs. 0.34 m/s, p = .001). Conversely, scars that supported hemodynamically stable sustained VT (6/15) were slower (367 ± 38 ms), had a smaller proportion of RM-BZ to RM-scar (median ratio 1.2 vs. 3.2, p = .059), and slower RM-BZ conduction speed (0.36 vs. 0.63 m/s, p = .036). RM guided ablation collocated within 66 ± 20% of RM-BZ, most concentrated around the RM-scar perimeter, with significant VT reduction (median 4.0 episodes preablation vs. 0 post, p < .001) at 11 ± 6 months follow-up.

CONCLUSION

Postinfarct scars appear significantly smaller than traditional 0.50 mV cut-offs suggest, with voltage thresholds unique to each patient.

Patient experience of very high power short duration radiofrequency ablation for atrial fibrillation under mild conscious sedation

BACKGROUND

Very high power short duration (vHPSD) radiofrequency ablation (RFA) may reduce ablation times and improve patient tolerability, permitting pulmonary vein isolation (PVI) under mild conscious sedation (mCS) and promoting same day discharge (SDD).

METHODS

First, a retrospective feasibility study was performed at 2 tertiary cardiac centres in the UK. Consecutive cases of first-time PVI using vHPSD ablation with 90 W lesions for up to 4 s were compared against cases performed using standard RF (sRF) and cryoballoon (Cryo) therapy. Subsequently, a prospective study of patients who had vHPSD or Cryo exclusively under mCS was undertaken. Questionnaires based on Likert and visual analogue scales (VAS) were used to measure anxiety, discomfort and pain.

RESULTS

In total, 182 patients (59 vHPSD, 62 sRF and 61 Cryo) were included in the retrospective study, with 53 (90%) of vHPSD cases successfully performed under mCS. PVI ablation time in the vHPSD group (5.8 ± 1.7 min) was shorter than for sRF (16.5 ± 6.3 min, p < 0.001) and Cryo (17.5 ± 5.9 min, p < 0.001). Fifty-one vHPSD and 52 Cryo patients were included in the prospective study. PVI ablation time in the vHPSD group was shorter than for the Cryo group (6.4 ± 2.9 min vs 17.9 ± 5.7 min, p < 0.001), but overall procedure duration was longer (121 ± 39 min vs 95 ± 20 min, p < 0.001). There were no differences in the patient experience of anxiety, discomfort or pain. SDD rates were the same in both groups (61% vs 67%, p = 0.49).

CONCLUSIONS

vHPSD RFA for PVI can be performed under mCS to achieve SDD rates comparable to cryoablation, without compromising patient experience.

Cryoballoon Pulmonary Vein Isolation as First-Line Treatment for Typical Atrial Flutter

OBJECTIVE

We aimed to compare cryoballoon pulmonary vein isolation (PVI) with standard radiofrequency cavotricuspid isthmus (CTI) ablation as first-line treatment for typical atrial flutter (AFL).

METHODS

Cryoballoon Pulmonary Vein Isolation as First-Line Treatment for Typical Atrial Flutter was an international, multicentre, open with blinded assessment trial. Patients with CTI-dependent AFL and no documented atrial fibrillation (AF) were randomised to either cryoballoon PVI alone or radiofrequency CTI ablation. Primary efficacy outcome was time to first recurrence of sustained (>30 s) symptomatic atrial arrhythmia (AF/AFL/atrial tachycardia) at 12 months as assessed by continuous monitoring with an implantable loop recorder. Primary safety outcome was a composite of death, stroke, tamponade requiring drainage, atrio-oesophageal fistula, pacemaker implantation, serious vascular complications or persistent phrenic nerve palsy.

RESULTS

Trial recruitment was halted at 113 of the target 130 patients because of the SARS-CoV-2 pandemic (PVI, n=59; CTI ablation, n=54). Median age was 66 (IQR 61-71) years, with 98 (86.7%) men. At 12 months, the primary outcome occurred in 11 (18.6%) patients in the PVI group and 9 (16.7%) patients in the CTI group. There was no significant difference in the primary efficacy outcome between the groups (HR 1.11, 95% CI 0.46 to 2.67). AFL recurred in six (10.2%) patients in the PVI arm and one (1.9%) patient in the CTI arm (p=0.116). Time to occurrence of AF of ≥2 min was significantly reduced with cryoballoon PVI (HR 0.46, 95% CI 0.25 to 0.85). The composite safety outcome occurred in four patients in the PVI arm and three patients in the CTI arm (p=1.000).

CONCLUSION

Cryoballoon PVI as first-line treatment for AFL is equally effective compared with standard CTI ablation for preventing recurrence of atrial arrhythmia and better at preventing new-onset AF.

TRIAL REGISTRATION NUMBER

NCT03401099.

Helium line ratio imaging in the C-2W divertor

A 2D imaging instrument has been designed and deployed on C-2W ("Norman") [H. Gota et al., Nucl. Fusion 61, 106039 (2021)] to study the plasma in the expander divertor by simultaneously measuring three neutral helium spectral lines. Ratios of these images, in conjunction with a collisional-radiative model, yield 2D maps of electron temperature and density. Almost the entire radial plasma cross-section (∼60 cm) can be mapped with a spatial resolution ≲1 cm. These data can, in principle, be acquired at 3 kHz. The neutral helium target is provided by a custom-built supersonic gas injector located inside the divertor vessel, which injects helium toward the magnetic axis and perpendicular to the camera sight-cone. Images of helium emission and reconstructed electron density and temperature profiles of the plasma produced from an end gun are presented. Voltages applied to concentric annular electrodes located in the divertors are used to stabilize beam-driven field reversed configuration plasmas. Magnetic field expansion is also employed to thermally isolate electrons from the end electrodes. Measurements of electron temperature and density in the divertor are important in order to study the effects of both the electrostatic biasing and the divertor magnetic field on electron confinement, neutral gas transport, and the overall machine performance.

OC-003 PORT POSITIONS IN TEP FOR SHORT PATIENTS: OUR EXPERIENCE

Introduction

Totally extraperitoneal repair (TEP) is a popular technique for repair of inguinal hernia. One common technique of TEP involves placement of one 10 mm port 1–2 cm below the umbilicus just off the midline, one 5 mm port 2–3 cm above the pubic symphysis, and a third 5 mm port between these 2 ports in the midline (Figure 1a). In case the distance from the superior border of the symphysis pubis to the inferior edge of the umbilicus is less than 15 cm, this leads to crowding of instruments and results in ergonomic problems during the operation. Daes has popularized eTEP for this indication. The aim is to shift the first 10 mm port to a position 5 cm superior and 4 cm lateral to the umbilicus (Figure 1b). eTEP has also found application in the repair of ventral hernias. However, for most inguinal hernias, we feel that eTEP is an overkill.

Methods

We place the first 10 mm port at the level of the superior border of the umbilicus and just lateral to it (Figure 1c). The two 5 mm ports are placed in the midline. Initial dissection is performed telescopically.

Results

This technique provides 2–3 cm of extra working space, which improves ergonomics while operating on patients with a short pubo-umbilical distance. Other parameters like operating time, postoperative pain and other complications remain the same.

Conclusion

We recommend placement of the 10 mm port at the superior border of the umbilicus, particularly in short patients.

P-011 FEASIBILITY OF VENTRAL-TAPP FOR VENTRAL HERNIA REPAIR IN A LOW INCOME COUNTRY LIKE INDIA

Aim

Minimal invasive repair is now the established procedure for ventral hernia. Surgeons are now validating newer techniques each year to deal with the ventral hernia. It becomes difficult to choose, best fit technique from this large armamentarium. For a low income country like India, ventral- trans abdominal preperitoneal (TAPP) technique is cost effective and uses simple polyester or polypropylene mesh.

Methods

For this article we used our experience with ventral-TAPP performed from July 1, 2021 to May 31, 2022. Patients were followed up for 6 months.

Results

In the above time period, we had performed 10 ventral-TAPP. Out of these, 3 had completed the follow up. Median age was 45.0 years, BMI was 26.56 kg/m2. One patient was male (33.33%). All patients were presented to surgery due to bulge or pain in the anterior abdominal wall.

The median hernia defect measured 80 mm, median mesh diameter was 15 cm and median operative time was 125 min. No intraoperative complications occurred.

Postoperatively, none of the patients developed complications. Length of hospital stay was 3.0 days. Six months after surgery, neither recurrence nor chronic pain were recorded.

Conclusion

We have concluded that mesh used in repair with ventral-TAPP costs one fourth to one-fifth to that of composite mesh used in intraperitoneal onlay mesh (IPOM) repair with the comparable results. So in a low income country like India, ventral TAPP should be a preferred approach.

Incidence of vascular complications for electrophysiology procedures in the ultrasound era: a single-centre experience over 10,000 procedures in the long term

BACKGROUND

Ultrasound (US) is being increasingly used to guide vascular access for electrophysiology (EP) procedures in many centres. Nonetheless, the incidence and predictors of vascular complications in the US era are limited. In this study, we describe our experience of vascular access-related complications associated with EP procedures which were performed with the routine use of US-guided vascular access.

METHODS

A total of 10,158 consecutive EP procedures in 8361 patients performed from April 2014 (when our centre moved to a policy of routine US-guided vascular access for EP procedures) to March 2022 were included. The outcome of interest was any vascular access-related complication that occurred within 7 days of the procedure; these were classified as severe if surgical intervention and/or blood transfusion was required, major if non-surgical intervention or delayed hospital discharge was required, or minor if it did not fulfil the criteria for severe or major.

RESULTS

During the study period, 2 (0.02%) severe vascular complications occurred, including 1 pseudo-aneurysm requiring surgery and 1 retroperitoneal haemorrhage requiring blood transfusion. Nine (0.09%) major complications occurred, including 6 hematomas managed by compression devices, 1 type B aortic dissection, 1 AV fistula managed conservatively and 1 haematoma managed conservatively but delayed hospital discharge. Eighteen (0.18%) minor haematomas were seen that did not require any intervention or delayed hospital discharge. On multivariable analysis, female sex [OR (95% CI): 2.5 (1.2, 5.4)] and use of an arterial access [OR (95% CI): 19.3 (7.1, 52.3)] were seen to be independent predictors of the 29 vascular complications.

CONCLUSION

With the use of US-guided vascular access in EP procedures, major vascular complications are exceedingly rare, particularly those needing surgical intervention. Our results provide additional evidence for scientific guidelines to support US use.

Relationship between Renal Function, Fibrin Clot Properties and Lipoproteins in Anticoagulated Patients with Atrial Fibrillation

Background: Mechanisms by which chronic kidney disease (CKD) influences fibrin clot properties in atrial fibrillation (AF) remain ill-defined. We aimed to investigate the effects of AF and CKD on fibrin clot properties and lipoproteins, and determine the relationship between these factors. Methods: Prospective cross-sectional study of patients recruited from cardiology services in Liverpool between September 2019 and October 2021. Primary groups consisted of anticoagulated AF patients with and without CKD in a 1:1 ratio. Control group comprised anticoagulated patients without AF or CKD. Fibrin clot properties were analysed using turbidity and permeation assays. Detailed lipoprotein characteristics, including total cholesterol, low-density lipoprotein cholesterol (LDL-C), small dense LDL and oxidised LDL, were measured. Results: Fifty-six anticoagulated patients were enrolled (median age 72.5; 34% female); 46 with AF (23 with CKD and 23 without CKD) and 10 controls. AF was associated with changes in three indices of fibrin clot properties using PTT (Tlag 314 vs. 358 s, p = 0.047; Abspeak 0.153 vs. 0.111 units, p = 0.031; Tlysis50% 884 vs. 280 s, p = 0.047) and thrombin reagents (Tlag 170 vs. 132 s, p = 0.031; Tmax 590 vs. 462 s, p = 0.047; Tpeak50% 406 vs. 220 s, p = 0.005) while the concomitant presence of CKD led to changes in fibrin clot properties using kaolin (Tlag 1072 vs. 1640 s, p = 0.003; Tmax 1458 vs. 1962 s, p = 0.005; Tpeak50% 1294 vs. 2046, p = 0.008) and PPP reagents (Tlag 566 vs. 748 s, p = 0.044). Neither of these conditions were associated with changes in fibrin clot permeability. Deteriorating eGFR was significantly correlated to the speed of clot formation, and CKD was independently associated with unfavourable clot properties (Tlag −778, p = 0.002; Tmax −867, p = 0.004; Tpeak50% −853, p = 0.004 with kaolin reagent). AF alone was not associated with changes in lipoprotein distribution while AF patients with CKD had lower total cholesterol, LDL-C and small dense LDL due to the presence of other risk factors. No significant relationship was observed between fibrin clot properties and lipoprotein distribution. Conclusions: There are important changes that occur in fibrin clot properties with AF and CKD that may account for the increased risk of thromboembolic complications. However, these changes in fibrin clot properties were not attributable to alterations in lipoprotein distribution.