Predictors of asymptomatic cerebral infarction associated with radiofrequency catheter ablation for atrial fibrillation using an irrigated-tip catheter

Establishment and Validation of the Nomogram Model and the Probability of Silent Cerebral Infarction After Ablation Atrial Fibrillation

BACKGROUND

The objective of this study is to establish and validate a nomogram model for predicting the probability of silent cerebral infarction following ablation of atrial fibrillation.

METHODS AND RESULTS

A retrospective observational study was conducted on the data of 238 patients with atrial fibrillation who underwent radiofrequency ablation in our hospital from October 2019 to December 2022. LASSO regression and multivariate logistics regression analysis were used to assess the independent risk factors for silent cerebral infarction after ablation. The AUC of the predictive model was 0.733 (95% CI, 0.649-0.816) and the internal validation (bootstrap = 1000) of the bootstrap method was 0.733 (95% CI 0.646-0.813). The Hosmer-Lemeshow test yields an insignificant p-value of X-squared = 10.212 and p-value = 0.2504, thus indicating an insignificant difference between predicted and observed values and good calibration results. The clinical impact curve (CIC) and clinical decision curve also prove that this graph is useful in the clinical setting.

CONCLUSION

We developed an easy-to-use nomogram model to predict the probability of silent cerebral infarction following radiofrequency ablation of atrial fibrillation. This model can provide a valid assessment of the probability of postoperative silent cerebral infarction in patients undergoing radiofrequency ablation of atrial fibrillation.

Atrial fibrillation catheter ablation associated silent cerebral emboli: A narrative review

The incidence of silent cerebral emboli (SCE) associated with atrial fibrillation catheter ablation (AFCA) is much higher than that of stroke/transient ischemic attack (TIA). Interventional electrophysiologists have been increasingly alerted to asymptomatic cerebral infarction over the years. Plentiful studies revealed that diagnostic definitions, detection modalities, energy sources, ablation strategies, perioperative anticoagulation regimens, and patient-related factors were associated with the risk of AFCA-associated SCE. Studies related to non-interventional procedures found that SCE may prompt stroke, cognitive decline, and dementia later in life, suggesting a possible role of AFCA-associated SCE in the cognitive function of patients with AF. However, there is no consistent evidence for this view to date. Given that the majority of patients with AF being elderly and the increased risk of cognitive impairment in AF itself, efforts should be made to minimize the occurrence of AFCA-associated SCE.

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.

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.

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.

Silent Cerebral Infarcts Following Left-Sided Accessory Pathway Ablation in Wolff-Parkinson-White (WPW) Syndrome: A Preliminary Report

Background

Catheter ablation is a routine procedure in patients with WPW syndrome. Silent cerebral infarcts (SCI) detected in magnetic resonance imaging may be a complication of the ablation procedure, but it is well documented only in atrial fibrillation ablation. Ablation of left-sided accessory pathways (L-AP) has a similar target area, but WPW patients differ from those with atrial fibrillation, due to lower initial risk of cerebral embolic events. The aim of this study was to determine whether the ablation of left-sided accessory pathways carries the risk of SCI.

Material/Methods

Twenty consecutive patients with overt L-AP referred for RF ablation in our center were included in the study. An irrigated ablation catheter was used in 8 patients, and a non-irrigated ablation catheter was used in 12 patients. Diffusion-weighted magnetic resonance imaging was performed pre-procedurally and on the next day after the ablation in all patients.

Results

Ablation procedures were completed without complications and there were no neurological symptoms following the procedure, although in 2 patients (10%), post-procedural diffusion-weighted magnetic resonance revealed new acute silent cerebral infarcts. Both patients with new cerebral lesions were female, and a non-irrigated catheter was used in both cases.

Conclusions

This is the first study documenting the presence of silent cerebral infarcts after WPW ablation. Further investigations are needed to evaluate the risk of silent cerebral infarcts associated with L-AP ablation.

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.

Incidence and Predictors of Catheterization-Related Cerebral Infarction on Diffusion-Weighted Magnetic Resonance Imaging

Introduction. The aim of this study was to examine the incidence and risk factors of catheterization-related CI in the contemporary era, using diffusion-weighted magnetic resonance imaging. Methods. We retrospectively analyzed consecutive 84 patients who underwent MRI (magnetic resonance imaging) after 2.81 ± 2.4 days (mean ± SD) of catheterization via aortic arch. We categorized the patients by the presence or absence of acute CI determined by diffusion-weighted MRI and analyzed the incidence and predictors. Results. Of 84 patients that underwent MRI after catheterization, acute CI was determined in 27 (32.1%) patients. In univariate analysis, dyslipidemia, age, coronary artery disease, antiplatelet agents, number of catheters used, urgent settings, and interventional procedures were significantly different. Multivariate analysis revealed dyslipidemia (odds ratio [OR], 4.46; 95% confidence interval [CI], 1.41–16.03; p = 0.01), higher age (OR, 1.09; 95% CI, 1.007–1.19; p = 0.03), and the number of catheters used (OR, 2.21; 95% CI, 1.21–4.36; p = 0.01) as independent predictors of the incidence of catheterization-related acute CI. Conclusions. Dyslipidemia, higher age, and number of catheters used were independent predictors for acute CI after catheterization. These findings imply that managing dyslipidemia and comprehensive planning to minimize the numbers of catheters are important.

A review of the safety aspects of radio frequency ablation

In light of recent reports showing high incidence of silent cerebral infarcts and organized atrial arrhythmias following radiofrequency (RF) atrial fibrillation (AF) ablation, a review of its safety aspects is timely. Serious complications do occur during supraventricular tachycardia (SVT) ablations and knowledge of their incidence is important when deciding whether to proceed with ablation. Evidence is emerging for the probable role of prophylactic ischemic scar ablation to prevent VT. This might increase the number of procedures performed. Here we look at the various complications of RF ablation and also the methods to minimize them. Electronic database was searched for relevant articles from 1990 to 2015. With better awareness and technological advancements in RF ablation the incidence of complications has improved considerably. In AF ablation it has decreased from 6% to less than 4% comprising of vascular complications, cardiac tamponade, stroke, phrenic nerve injury, pulmonary vein stenosis, atrio-esophageal fistula (AEF) and death. Safety of SVT ablation has also improved with less than 1% incidence of AV node injury in AVNRT ablation. In VT ablation the incidence of major complications was 5-11%, up to 3.4%, up to 1.8% and 4.1-8.8% in patients with structural heart disease, without structural heart disease, prophylactic ablations and epicardial ablations respectively. Vascular and pericardial complications dominated endocardial and epicardial VT ablations respectively. Up to 3% mortality and similar rates of tamponade were reported in endocardial VT ablation. Recent reports about the high incidence of asymptomatic cerebral embolism during AF ablation are concerning, warranting more research into its etiology and prevention.

Influence of cardioversion on asymptomatic cerebral lesions following atrial fibrillation ablation

PURPOSE

Asymptomatic cerebral lesions detected by diffusion-weighted magnetic resonance imaging (MRI) following atrial fibrillation (AF) ablation were reported in recent years. It was reported that cardioversion during the procedure of AF ablation was one independent risk factor of asymptomatic cerebral lesions. However, in some studies, the similar association between asymptomatic cerebral lesions and intraprocedural cardioversion was not observed. Given the inconsistent results, we did a meta-analysis to explore the influence of intraprocedural cardioversion on the asymptomatic cerebral lesions detected by MRI following AF ablation.

METHODS

Studies exploring the association between cardioversion during AF ablation and asymptomatic cerebral lesions following AF ablation were systematically searched in PubMed, Web of Science and the Cochrane Library Databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were pooled. Subgroup and sensitivity analyses were performed to explore the source of heterogeneity.

RESULTS

Nine studies involving 813 participants were included in the present meta-analysis. When we pooled data from nine studies using fixed-effects model, we found cardioversion during the procedure significantly increased the risk of asymptomatic cerebral lesions detected by MRI following AF ablation (pooled OR = 1.793, 95% CI 1.201-2.678, I (2) = 38.8%, P heterogeneity = 0.109).

CONCLUSIONS

Cardioversion during AF ablation significantly increased the risk of asymptomatic cerebral lesions on MRI following the procedure. Additional studies are required to further verify the association.

Association between ablation technology and asymptomatic cerebral injury following atrial fibrillation ablation

BACKGROUND

Asymptomatic cerebral injury (ACI) detected by diffusion-weighted magnetic resonance imaging (MRI) following atrial fibrillation (AF) ablation has been reported recently. The purpose of this study was to provide an overview of the incidence of ACI detected by MRI following AF ablation and to explore the association between ablation technology and ACI by systematically reviewing published trials.

METHODS AND RESULTS

PubMed, Web of Science, and the Cochrane Library Databases were systematically searched for studies exploring ACI detected by MRI following AF ablation. Incidence of ACI, odds ratios, and 95% confidence intervals (CIs) were pooled. We identified 21 eligible studies. The combined ACI incidence across all studies was 15.9% (95% CI: 0.124-0.202). We also did a subgroup analysis stratified by different technologies. The incidence of ACI stratified by ablation technology was 13.0%, 27.6%, 12.5%, 17.3%, and 32.6% of the irrigated radiofrequency (RF), multielectrode-phased RF pulmonary vein ablation catheter (PVAC), cryoballoon, laser balloon, and nMARQTM groups, respectively.

CONCLUSIONS

The incidence of ACI following AF ablation with PVAC was higher than with other technologies. Uninterrupted oral anticoagulant (OAC) during the procedure could lower the incidence of ACI. It seems prudent not to interrupt OACs during the procedure. In addition, intraprocedural activated clotting time was associated with ACI. Different MRI diagnostic criteria for ACI also influenced the results. To facilitate the future research, a generally accepted definition for silent cerebrovascular ischemia suitable to different kinds of MRI is needed.