Atrial Fibrillation Recurrence Research Articles

Long-term efficacy and safety of ablation for atrial fibrillation in patients with hypertrophic cardiomyopathy

Abstract Background Hypertrophic cardiomyopathy (HCM) is often accompanied by atrial fibrillation (AF) but data on safety and long-term outcomes after catheter ablation for AF in HCM are scarce. Purpose To investigate safety, long-term efficacy and clinical outcomes following AF ablation in patients with HCM and in matched controls. Methods Patients with HCM (n=76) undergoing a first catheter ablation for AF or atrial flutter between 1999 and 2022 at a University Hospital in Sweden were included (age 64±12 years, 43% female). Diagnosis of HCM was based on the European Society of Cardiology definition (left ventricular wall thickness ≥15 mm or ≥13 mm not solely explained by abnormal loading conditions, and combined with family history, genetic components and/or electrocardiogram abnormalities). Patients with HCM were matched with controls (n=152) based on age, gender, ablation type and intervention-year. Patients were followed for a mean of 5 years and study endpoints included heart failure hospitalization (HFH), stroke and mortality. Cox regression analyses were performed for the association between HCM and the endpoints. Results Among the overall population, 121 (53%) underwent pulmonary vein isolation (PVI), 62 (27%) isthmus ablation and 45 (20%) His-Bundle ablation. Patients with HCM had a shorter mean duration of AF before ablation (48 months vs. 66 months; p=0.047) and more severe symptoms as indicated by a higher EHRA class (EHRA class IV: 30% vs. 10%; p<0.01). Procedural success rate of PVI and isthmus ablation was lower in patients with versus without HCM (88% vs. 97%; p=0.02). Procedure related complications (vascular complications, tamponade) were overall similar in both groups (9% in HCM vs. 5% in controls, p=0.17) except for higher rates of pulmonary oedema in patients with HCM (7% vs 1%, p=0.03). There was a nearly two-fold increase in risk of AF recurrence after PVI or isthmus ablation in patients with HCM compared to controls (OR 1.95; 95% CI 1.06-3.58; p=0.03). During follow-up, patients with HCM had an increased risk of HFH (HR 2.55, 95% CI 1.21-5.36, p=0.01) but not of stroke or mortality (Figure 1). Conclusion AF ablation was overall safe in patients with HCM but less effective. Patients with HCM had an increased risk of the individual endpoint of HFH after AF ablation but not stroke or mortality during long-term follow-up.

Prediction of atrial fibrillation recurrence after ablation: the impact of machine learning and recurrence during the blanking period

Abstract Introduction Pulmonary vein isolation is superior to antiarrhythmic drugs for rhythm control in patients with atrial fibrillation (AF). Nevertheless, recurrences within the first year are still significant. Several clinical risk scores were developed to predict AF recurrence; however, despite good results in development cohorts, the results in external validation are usually poor, limiting the general applicability of these scores. Purpose We aimed to develop machine learning (ML) models to predict AF recurrences within the first year after catheter ablation and compare their performance with conventional risk scores. Methods We used a retrospective dataset of a tertiary hospital center, including all consecutive patients submitted to the first AF ablation between 2017 and 2021. The dataset included 76 features: patient characteristics, medical history, baseline echocardiography, calcium score, procedure variables, and early recurrence (ER) during the 90-day blanking period. The outcome was defined as the occurrence of an electrocardiographically documented late recurrence (LR) of atrial tachycardia/AF > 30s between 3-12 months. Three different supervised ML models (penalized logistic regression, random forests, and XGBoost) were developed on the training cohort, and hyperparameters were tuned using 10-fold cross-validation. A testing dataset was held out to estimate the final performance (25%). The following risk scores were calculated: APPLE, CAAP-AF, and BASE-AF2 (the last includes ER). Areas under the curve (AUC) of receiver operating characteristic curves were compared using DeLong’s test. Results 679 patients were included: 62.7% males, median age of 59±16 years, and 78.2% with paroxysmal AF. The median time from diagnosis to ablation was 2±4 years. 74.2% underwent radiofrequency ablation and the remaining cryoablation. ER occurred in 12.5%, and most of these patients also experienced LR (68.7 vs 19.6% in those without ER, p<0.001). LR was observed in 25.6%. The XGBoost model showed the best performance with an AUC 0.774, 95% confidence interval (CI) 0.688–0.844) outperforming existing scores (picture 1): APPLE score AUC 0.607, 95% CI 0.562–0.653, p-value<0.001; CAAP-AF score AUC 0.622, 95% CI 0.576–0.668, p-value=0.002; BASE-AF2 AUC 0.628, 95% CI 0.581–0.675, p-value= 0.003. Variable importance analysis showed a significant drop in the performance of the models when ER was not considered, indicating its high importance in predicting LR (picture 2). Conclusions Recurrence during the blanking period was the most important predictor of LR in our population. The ML model was superior to conventional risk scores. ML models might be an essential tool to improve the prediction of outcomes and clinical decision-making for optimal follow-up.ROC curvesFeature Importance

A nurse-led intervention improves quality of life and reduces arrhythmic recurrences in patients undergoing atrial fibrillation ablation. Results of the NURSECAT-AF randomized clinical trial

Abstract Background/Introduction Atrial fibrillation (AF) is a prevalent condition that can lead to a decrease in quality of life and frequent re-hospitalizations. Some data suggest that integrated care nurse-led may blunt these consequences in unselected patients with AF, but not all studies support this. While AF ablation is becoming a cornerstone treatment for symptomatic patients with AF, it is unclear what impact a nurse-led intervention would have on these, quite likely, more receptive patients. Purpose To assess the impact of nurse-led intervention on quality of life among AF patients undergoing ablation. Methods We conducted a single-centre prospective randomised clinical trial to test the effect of an expert nurse-based intervention consisting of an educational programme on AF, support for the patient undergoing cardiac ablation to ensure its success, and management of risk factors associated with this arrhythmia. The control group underwent standard medical follow-up. Patient selection was based on chronological order. Only patients who underwent their first ablation and did not have heart failure were included. The primary endpoint was quality of life at 12 months post-ablation using the Arrhythmia-Specific Scale in Tachycardia and Arrhythmia (ASTA) questionnaire (higher values denote impaired quality of life). Secondary endpoints were AF knowledge and satisfaction at 15 days post-ablation using validated instruments, symptoms using the ASTA questionnaire as well, and readmissions rates, emergency room visits, and AF recurrence rates over a one-year period. Results 116 patients were screened (50 were excluded mostly because were re do). A total of 66 patients were eventually included and randomized (33 per arm; mean age [mean±SD] 63±10 years; 44 men [67%]). At 12 months, quality of life was significantly better in the intervention group than in the control group (4.5 ± 6.1 vs 0.57 ± 2.3, respectively, p=0.001)(Figure). Furthermore, satisfaction levels (17 ± 4.1 vs 12.7 ± 5.4, p>0.001) and disease knowledge (20.5 ± 5.1 vs 15.9 ± 4.5, p<0.001) were higher in the intervention group. Patients in the control group experienced a higher symptom burden during the first year (0.6 ± 1.5 vs 3.8 ± 4.5, p<0.001. Relevant clinical endpoints such as readmissions (3% vs 18.2%, p=0.046), emergency room visits (21.2% vs 57.5%, p=0.021), and arrhythmia recurrences (15.2% vs 45.5%, p=0.02) were all significantly lower in the intervention group. Conclusion(s) Nurse-led integrated care for patients undergoing AF ablation yields substantial improvements in quality of life and symptomatic relief at one year post-procedure. Additionally, it enhances patient knowledge of AF and satisfaction levels, and reduces readmissions, emergency room visits, and arrhythmia recurrences.

Long-term patient clinical benefits and healthcare utilization after pulsed field ablation in paroxysmal atrial fibrillation: sub-analyses from the multicenter inspIRE trial

Abstract Background/Introduction The treatment of atrial fibrillation (AF) with pulsed field ablation (PFA) aims to prevent AF recurrence while reducing complications from the ablation modality. Similar to thermal ablation, PFA has proven to be safe and effective for treatment of paroxysmal AF (PAF); however, there is scarce evidence on patient-related clinical benefits, including healthcare utilization, using this new energy modality. Purpose The objective of this study is to assess long-term clinical improvements in patient care, symptoms, and quality-of-life (QOL) after PFA ablation in PAF. Methods InspIRE was a multicentre study evaluating the safety and efficacy of variable loop PFA catheters integrated with a 3D mapping system for treatment of symptomatic PAF. Patients were followed for up to 12 months for the following QOL and healthcare utilization endpoints: Atrial Fibrillation Effect on Quality-of-Life (AFEQT) score, Class I/III AAD utilization, repeat ablation, incidence of direct current cardioversion (DCCV), and cardiovascular (CV) hospitalization. Post-hoc Kaplan-Meier estimates for clinical benefit success at 12 months were provided. Success was defined as composite freedom from occurrence of the following events post-blanking: repeat ablation, CV hospitalization, AAD utilization, and DCCV post-blanking. Predictors of clinical benefit success were explored via multivariate logistic regression analysis. Results A total of 186 enrolled patients (59±10 years; 70.0% male; CHA2DS2-VASC score 1.3±1.2) underwent PVI. Compared to baseline: 1) improvements in the AFEQT composite score were seen at 12 months (P<0.001); 2) Class I/III AAD use was reduced from 81.7% to 20.1% at 6-12 months (P<0.05); and 3) the proportion of subjects with DCCV decreased from 13.7% up to 12 months before the index procedure to 3.3% up to 12 months after the index procedure (P<0.001, Figure 1). Minimal clinically important difference in QoL (≥5 points improvement in AFEQT) was achieved in 85.2% of patients. Patients free from 12-month AF/AT/AFL recurrence (asymptomatic and symptomatic) had significantly greater improvements in AFEQT scores from baseline to 12 months versus those with recurrence (P=0.01). The clinical benefit success rate at 12 months was 87.5% (Figure 2). Patients who failed the clinical benefit endpoint were counted, including those with repeat ablation (7.5%), those on new or higher dose of AAD (6.5%), those hospitalized for CV (4.8%), and those who had DCCV post-blanking (1.6%). Multivariate logistic regression analysis showed that left ventricle ejection fraction <60% (OR: 0.22; 95% CI: 0.08-0.62; P<0.05) and incidence of diabetes (OR: 7.25; 95% CI: 2.00, 26.3; p<0.05) were associated with a higher risk of clinical benefit failure. Conclusions PFA ablation of PAF patients led to a clinical benefit success rate of 87.5%, with clinically meaningful improvement in QOL, as well as a reductions in AAD use, cardioversion, and hospitalization.Figure 1.Improvements in QoL and HealthFigure 2.Kaplan-Meier Analysis of Time

A multi-center retrospective cohort analysis of age and racial disparities in patients undergoing repeat ablation for recurrent atrial fibrillation

Abstract Introduction Atrial fibrillation (AF) is the most common type of cardiac arrhythmia, and its prevalence has been increasing worldwide. Current data shows that AF is more common in white males compared to blacks despite blacks having multiple cardiovascular comorbidities. There is paucity of data showing the recurrence of AF re-ablation after index ablation specifically as it pertains to race, gender, and age. We sought to explore the rates of recurrent AF re-ablation in this retrospective cohort analysis. Methods Using a multi-center database, we examined 23,558 encounters and 10,530 had readmission records i.e. readmitted within 3 years. The encounters included adults (18+) who had an ablation procedure for atrial fibrillation between 1/1/2018-06/30/2020. We used binary logistic regression models and Tukey-Kramer procedure to analyze pairwise comparisons among different subgroups of race, sex, and age group. The primary endpoint was recurrence of repeat ablation. Secondary endpoints included non-fatal stroke and myocardial infarction. Results Our sample size was 23,558 patients, 20,276 were white patients (86%) and 3,282 were non-white patients (14%). The average age was 66.29 years (SD 10.43) and average age at the time of repeat ablation was 65.97 years. The average BMI was 21.55. Out of the 23,558 patients, 14.30% (N= 3368) had re-ablation within 3 years of the index ablation. The odds ratio of re-ablation for patients in their 50s is 1.4229 (95% CI [1.1172, 1.8122]) compared to patients in their 80s. Similarly, the odds ratio is 1.4330 (95% CI [1.1466, 1.7909]) for the 60-69 group, 1.3075 (95%CI [1.0458, 1.6346]) for the 70-79 group and 1.3443 (95% CI [1.0088, 1.7914]) for patients below 50 compared to over 80 group. The LR for re-ablation was 0.8438 (p=0.3583) in females. The incidence of non-fatal stroke and MI were 0.27% (N= 63) and 0.19% (N= 45). Average length of time to re-ablation was 415.5 days. Discussion When controlling for age group and sex, race was not significantly associated with an increased likelihood of repeat ablation. When controlling for race and age group, sex was not significantly associated with an increased likelihood of repeat ablation. When controlling for race only, females were not at a higher risk of re-ablation. However, when controlling for race and sex, patients in their 50s are 42.3% more likely to have re-ablation when compared to patients in their 80s. In contrast, the age of patients at their first ablation increased, there appeared to be a rising trend indicating a higher chance of AF recurrence within 3 years when controlling for race and sex. Conclusion The incidence of repeat AF ablation is not higher in racial minorities when compared to whites. Interestingly, there appears to be an decreasing rate of AF re-ablation in older patients despite a higher rate of AF recurrence as age increases possibly owing to more conservative therapeutic approach such as medical management.

Ppulsed field ablation and ultra-high-density mapping for PVI: use of machine learning and data augmentation to guide procedure and identify recurrent tachycardia mechanisms at one-year follow-up

Abstract Background In managing atrial fibrillation (AF), radiofrequency and cryoablation have been cornerstone techniques for achieving pulmonary vein isolation (PVI). Recently, pulsed-field ablation (PFA) has introduced a novel method for PVI. There remains a gap in knowledge regarding the permanent efficacy of ablation, related explicitly to acute lesion characteristics following PVI. Purpose Our study delves into an in-depth examination of acute lesion characteristics following PFA-PVI through ultra-high-density mapping (UHDM). We aim to identify specific clinical, anatomical, and periprocedural lesion features independently related to 1) intraoperative identification of UHDM non-isolated gaps with electrical conduction after first isolation and 2) three months follow-up recurrency of specific arrhythmias. Methods Results The present study includes 204 patients submitted to PFA-PVI for AF. UHDM guided all procedures to identify non-isolated gaps with electrical conduction. Perioperative and 3-month follow-up data were collected prospectively and analyzed. To build our prediction model, avoiding biases related to the unbalanced nature of the data, data augmentation was performed with SMOTE (Synthetic Minority Over-sampling Technique). Two machine learning (ML) models have been built, using logistic regression as learner, to predict the presence of isolation gaps identified by UHDM and follow-up recurrence of arrhythmias. A 20-fold cross-validation has been performed to train and test the models. The non-isolated gap was detected and immediately corrected in 14 (6.9%) patients and was present more often in patients with larger left atria (LA) (p<0.0001) and those with persistent AF (p=0.02). The ML model achieved an AUC of 0.88 in the prediction of the non-isolated gap after PFA (Precision: 0.65; Sens.: 0.90; F1: 0.76; Spec.: 0.83; NPV: 0.96). At three months follow-up, no patient experienced recurrent AF; recurrent roof-dependent atrial tachycardia was present in 10 (4.9%). Patients with recurrent atrial tachycardia had a significantly narrower remaining atrial-roof conduction bridge (p=0.01) identified intra-procedurally by UHDM, significantly larger LA (p=0.03), and non-significant trend for older age (p=0.07). The ML model achieved an AUC of 0.86, predicting recurrent tachycardia after PFA (Precision: 0.63; Sens.: 0.86; F1: 0.72; Spec.: 0.82; NPV: 0.94). Conclusions Consistent use of UHDM can help identify non-isolated gaps with electrical conduction that may occur even after PVI with updated technologies, such as PFA. Non-isolated gaps should be expected, particularly in patients with larger LA, where UHDM could be of particular use. Moreover, UHDM can help predict the eventual recurrence of arrhythmias. Again, LA size plays an essential role in such recurrencies, together with the size of the remaining conducting tissue "bridges" within the LA roof, measure by UHDM.

Early repeat catheter ablation in patients with early recurrent arrhythmia

Abstract Background Repeat catheter ablation reduces adverse cardiovascular endpoints in patients with recurrent atrial tachyarrhythmia after index ablation. However, when to proceed with re-ablation in patients with early recurrent arrhythmia is unknow. Objective In this study, we aim to access the effectiveness of early repeat ablation on cardiovascular outcomes in early recurrent atrial tachycardia patients. Methods A total of 502 post-ablation patients, who experienced early atrial tachyarrhythmia recurrence within 6 months outside the blank period post index ablation and had undergone a repeat ablation, were consecutively enrolled from China AF registry from January 2012 to December 2018. Early repeated ablation (ERA) was defined as patients underwent a subsequent catheter ablation procedure within early recurrent period, then late repeated ablation (LRA) referred to a redo procedure that performed after 6 months since the de novel ablation. Cox proportional hazard models were used to estimate the effect of early re-ablation on primary endpoint (a composite of cardiovascular death, stroke and cardiovascular rehospitalization) and secondary endpoint (each component of primary outcome and AF/AT recurrence). Results The median follow-up time was 26 months after the redo-AF/AT ablation. First primary composite outcome occurred in 39 of the patients received early re-ablation (24.38 per 100 person-years) and in 136 of the patients performed with late re-ablation (39.77 per 100 person-years) (HR = 0.55, 95% CI = 0.38-0.79; P0.001). Cardiovascular re-hospitalization (hazard ratio 0.52 95% confidence interval [0.36; 0.73]) and AF recurrence occurred less often (hazard ratio 0.76, 95% confidence interval [0.58; 0.98]) in the ERA group. No significant difference between the two groups was found in terms of cardiovascular death, stroke and major bleeding events. Conclusion Early initiation of redo-ablation conveys better clinical benefit in patients with early arrhythmia recurrence.

Catheter ablation vs medical management for atrial fibrillation in patients with heart failure: a systematic review and metanalysis

Abstract Background Current guidelines recommend a class IIa recommendation for catheter ablation in Atrial Fibrillation [AFIB]. Traditionally, catheter ablation has been known to be more effective in maintaining sinus rhythm than pharmacological management. However, there is sparse evidence to suggest that this translates to improved clinical outcomes in patients with heart failure. We did a systematic review and meta-analysis of randomized trials to compare the efficacy of ablation vs medical management for AFIB in heart failure. Methods A systematic search was conducted for randomized trials from inception to Jan 2024 for studies comparing the outcomes of catheter ablation vs medical management for AFIB in heart failure. The primary outcome was all-cause mortality. Secondary outcomes were cardiovascular (CV) mortality, heart failure hospitalizations, change in LV ejection fraction (LVEF), AF recurrence rate, 6-minute walk test (6MWT), change in MLHFQ scores and cerebrovascular events. Random-effects models were used to calculate the pooled incidence, mean difference (MD), and risk ratios (RRs) with 95% confidence intervals (CIs). Results A total of 10 RCTs with 2,348 patients were included in this study. Pulmonary vein isolation was the mainstay ablation strategy used. Compared with medical management, Ablation was associated with a significant reduction in all-cause mortality (RR- 0.61; 95% CI, 0.48-0.78; P<0.0001). Ablation was also associated with lower cardiovascular (CV) mortality (RR- 0.52; 95% CI, 0.36-0.75; P<0.0004), heart failure hospitalizations (RR- 0.67; 95% CI, 0.54-0.82; P<0.0001) and AF recurrence rate (RR- 0.43; 95% CI, 0.25-0.75; P<0.003). The study showed an improvement in LVEF (RR - 6.05; 95% CI, 3.35-8.75; P<0.0001), 6MWT (RR- 13.99; 95% CI, 4.18-23.81; P<0.005) and in MLHFQ score (RR -6.98; 95% CI, -12.03 to -1.93; P<0.007. There was a statistically significant difference between the 2 cohorts in the rates of cerebrovascular events (RR- 0.68; 95% CI, 0.35-1.30; P<0.24). Conclusion Randomized trials have shown clear benefits with catheter ablation compared to medical management for AFIB in heart failure. Ablation has demonstrated significantly lower all-cause mortality, reduced CV mortality, HF hospitalizations, AFIB recurrence rate, and improvement in LVEF. Patients who underwent catheter ablation showed improvement in functional outcomes like 6MWT and MLHFQ scores. There was no difference in the incidence of cerebrovascular events compared to medical management. This study adds to the growing evidence in the literature for ablation therapy; however, more trials are needed to identify patients for optimal benefits across the spectrum of heart failure patients.Forest PlotsForest Plots

A meta-analysis of the safety and efficacy of pulsed-field versus conventional thermal ablation for atrial fibrillation

Abstract Background Since pulsed-field ablation (PFA) specifically targets myocardial tissue, it has become a cutting-edge substitute for radiofrequency (RF) and cryoablation. Purpose We aim to compare the safety and efficacy of PFA vs thermal ablation for AF ablation. Methods We conducted a systematic review and meta-analysis synthesizing randomized controlled trials (RCTs) and observational comparative studies, which were retrieved by systematically searching: PubMed, EMBASE, Web of Science, SCOPUS, and Cochrane through September 2023. RevMan version 5.4 software was used to pool dichotomous data using risk ratio (RR) and continuous data using mean difference (MD) with a 95% confidence interval (CI). Results Seventeen studies with a total of 2,255 patients were included. PFA was significantly associated with a decreased AF recurrence (RR: 0.65, 95% CI [0.51, 0.84], P= 0.0010) but not any arrhythmia recurrence (RR: 0.87, 95% CI [0.69, 1.09], P= 0.22). Also, PFA was significantly associated with decreased total procedure time (MD: -15.15, 95% CI [-20.23, -10.07], P< 0.00001) and heart rate (MD: -7.56, 95% CI [-12.78, -2.34], P= 0.005); however, there was no significant difference between PFA and thermal ablation in fluoroscopy time (MD: 2.83, 95% CI [-0.38, 6.04], P= 0.08). PFA decreased phrenic nerve palsy (RR: 0.38, 95% CI [0.15, 0.98], P= 0.05) and esophageal lesions (RR: 0.09, 95% CI [0.01, 0.69], P= 0.02); however, PFA was significantly associated with increased pericardial tamponade (RR: 6.14 with 95% CI [1.43, 26.33], P= 0.01). Conclusion PFA was significantly associated with decreased AF recurrence, heart rate, total procedure time, phrenic nerve palsy, esophageal lesion, and increased incidence of pericardial tamponade compared with thermal ablation. However, current evidence is mainly weighted by observational studies, requiring further large-scale randomized trials.Figure

Role of Steroid Therapy in Preventing Recurrence of Atrial Fibrillation After Ablation: A Systematic Review and Meta-Analysis

Role of Steroid Therapy in Preventing Recurrence of Atrial Fibrillation After Ablation: A Systematic Review and Meta-Analysis

Temporal trends of catheter ablation procedures in patients with atrial fibrillation and atrial flutter: A nationwide cohort study

BackgroundCatheter ablation is a well-established treatment to prevent atrial fibrillation (AF) and atrial flutter (AFL) recurrences and to relieve symptoms, whereas pacemaker implantation and atrioventricular node (AVN) ablation is used for rate control when medical therapy fails. AimsWe investigated temporal trends and patient characteristics in catheter ablation procedures for AF, AFL and AVN in Finland between 2012–2018. MethodsFinnish AntiCoagulation in Atrial Fibrillation (FinACAF) is a registry-based study including all patients with AF or AFL in Finland between 2012–2018. ResultsThe number of patients with AF or AFL diagnosis in Finland increased from 185057 to 243802 between 2012–2018 and a total of 8954 first-time catheter ablation procedures were performed. Of them, 4909 (54.8 %) were AF ablations, 2731 (30.5 %) AFL ablations and 1314 (14.7 %) AVN ablations. The procedural numbers increased from 457/year to 934/year for AF, from 223/year to 553/year for AFL and from 114/year to 238/year for AVN. Altogether, 0.65% of all patients with diagnosed AF or AFL underwent AF, AFL or AVN ablation in 2018. The mean age of the patients increased in all ablation groups. Patients undergoing AF and AFL ablations were predominantly men (69.7 % and 74.6 % respectively) whereas patients undergoing AVN ablation were more often women (56.9%). ConclusionsThe use of catheter ablation more than doubled during 2012–2018 and the increase was particularly seen in the elderly patients. Nevertheless, only a minority of AF and AFL patients were treated with catheter ablations.

Clinical usefulness of digital twin guided virtual amiodarone test in patients with atrial fibrillation ablation

It would be clinically valuable if the efficacy of antiarrhythmic drugs could be simulated in advance. We developed a digital twin to predict amiodarone efficacy in high-risk atrial fibrillation (AF) patients post-ablation. Virtual left atrium models were created from computed tomography and electroanatomical maps to simulate AF and evaluate its response to varying amiodarone concentrations. As the amiodarone concentration increased in the virtual setting, action potential duration lengthened, peak upstroke velocities decreased, and virtual AF termination became more frequent. Patients were classified into effective (those with virtually terminated AF at therapeutic doses) and ineffective groups. The one-year clinical outcomes after AF ablation showed significantly better results in the effective group compared to the ineffective group, with AF recurrence rates of 20.8% vs. 45.1% (log-rank p = 0.031, adjusted hazard ratio, 0.37 [0.14-0.98]; p = 0.046). This study highlights the potential of a digital twin-guided approach in predicting amiodarone’s effectiveness and improving personalized AF management. Clinical Trial Registration Name: The Evaluation for Prognostic Factors After Catheter Ablation of Atrial Fibrillation: Cohort Study, Registration number: NCT02138695. The date of registration: 2014-05. URL: https://www.clinicaltrials.gov; Unique identifier: NCT02138695.

Echocardiographic Assessment of Left Atrial Mechanics in Patients with Atrial Fibrillation Undergoing Electrical Cardioversion: A Systematic Review.

Background: To date, only a few studies have evaluated left atrial (LA) mechanics in patients with atrial fibrillation (AF) scheduled for electrical cardioversion (ECV). The present systematic review has been primarily designed to summarize the main findings of these studies and to examine the overall effect of AF on left atrial reservoir strain (LASr) in patients undergoing ECV. Methods: All the echocardiographic studies evaluating the effect of AF on LA mechanics in patients scheduled for ECV, selected from the PubMed and EMBASE databases, were included. There was no limitation of time period. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Results: The full texts of 12 studies with 880 AF patients were analyzed. The pooled ECV success rate was 91.5% (range 65.8-100%). Over a median follow-up of 5.4 months (range 0.3-12 months), 35.2% of the patients (range 5-68.8%) experienced AF recurrence. At baseline, the average LASr was 11.4% (range 6.2-17.7%). A reduced LASr before ECV was strongly correlated with reduced left atrial appendage (LAA) flow velocities and/or thrombosis. The main independent predictors of cardioversion failure were impaired LASr and previous AF history. A severe LASr deterioration was independently correlated with AF recurrence after ECV. The other independent predictors of AR relapses were LA asynchrony, reduced difference between post- and pre-ECV LASr, and reduced right atrial reservoir strain. Conclusions: LASr assessment before ECV may provide useful prognostic information about AF relapses and improve the refinement of the thromboembolic risk of AF patients scheduled for ECV.

The consequences of cardiac autonomic nervous system modulation during pulmonary vein isolation: A review.

Pulmonary vein isolation (PVI) is a well-established treatment modality for atrial fibrillation (AF). Apart from the desired effect regarding the arrhythmic substrate within the left atrium, PVI commonly leads to modulation of the intrinsic cardiac autonomic nervous system (ICANS). Using the available literature, this article presents the anatomy of ICANS and describes methods of assessing its function, mainly focusing on heart rate (HR) variability metrics. Then, we summarize the modern pathophysiological outlooks on the onset and recurrence of AF and explain how the arrhythmia and the activation of ICANS are intertwined. Further, the article discusses the extent, dynamics and persistence of ICANS modulation during PVI, accounting for various modalities and procedural strategies. Both the potential benefits and pitfalls of such modulation are explored, considering AF recurrence, HR and HR variability changes, as well as the unclear effect on ventricular arrhythmias and nerve remodeling. Finally, the article aims to outline further directions of research necessary to improve our understanding of ICANS and its modulation.

Innovative approaches to the management of recurrent atrial fibrillation, aortic dilation, and Brugada syndrome.

Innovative approaches to the management of recurrent atrial fibrillation, aortic dilation, and Brugada syndrome.

Circulating soluble suppression of tumorigenicity-2 and the recurrence of atrial fibrillation after catheter ablation: A meta-analysis.

Soluble suppression of tumorigenicity-2 (sST-2), a marker of myocardial fibrosis and remodeling, has been related to the development of atrial fibrillation (AF). The aim of this meta-analysis was to evaluate the relationship between baseline serum sST-2 levels and the risk of AF recurrence after ablation. Relevant observational studies were retrieved from PubMed, Web of Science, Embase, Wanfang and China National Knowledge Infrastructure (CNKI). A random-effects model was used to combine the data, accounting for between-study heterogeneity. Fourteen prospective cohorts were included. Pooled results showed higher sST-2 levels before ablation in patients with AF recurrence compared to those without AF recurrence (standardized mean difference = 1.15, 95% confidence interval [CI] = 0.67 to 1.63, P < 0.001; I2 = 92%). Meta-regression analysis suggested that the proportion of patients with paroxysmal AF (PaAF) was positively related to the difference in serum sST-2 levels between patients with and without AF recurrence (coefficient = 0.033, P < 0.001). Subgroup analysis showed a more remarkable difference in serum sST-2 levels between patients with and without AF recurrence in studies where PaAF was ≥ 60% compared to those where it was < 60% (P = 0.007). Further analyses showed that high sST-2 levels before ablation were associated with an increased risk of AF recurrence (odds ratio [OR] per 1 ng/mL increment of sST-2 =1.05, OR for high versus low sST-2 = 1.73, both P values < 0.05). In conclusion, high sST-2 baseline levels may be associated with an increased risk of AF recurrence after catheter ablation.

Evaluating the Prognostic Significance of Cystatin C Level Variations Pre- and Post-Radiofrequency Catheter Ablation in the Recurrence of Persistent Atrial Fibrillation.

To investigate the correlation between persistent atrial fibrillation (AF) recurrence and alterations in cystatin C levels pre- and post-radiofrequency catheter ablation (RFCA). This study encompassed 114 patients diagnosed with persistent AF. Their serum cystatin C levels were assessed both prior to and 3 months after undergoing an RFCA procedure. The variance in cystatin C levels before and after RFCA is represented as ΔCystatin C. Subsequently, we compared these values between two groups: patients who did not experience a recurrence of AF (n = 79) and those who did experience a recurrence (n = 35). A significant reduction in cystatin C levels post-RFCA in both groups, with a more pronounced decrease observed in the non-recurrence group. Moreover, the recurrence group exhibited larger left atrial diameter and volume before RFCA compared to the non-recurrence group. Cox regression analysis indicated that smaller reductions in serum cystatin C levels and greater left atrial volumes before RFCA were associated with an increased risk of recurrence, after adjusting for covariates. The receiver operating characteristic curve indicated an elevated probability of clinical recurrence of AF post-RFCA in patients with a cystatin C decline < 0.08 mg/L (AUC 0.64). The Kaplan-Meier survival analysis revealed that patients with a cystatin C decline > 0.08 mg/L exhibited significantly higher rates of remaining free from recurrence following RFCA across a 24-month follow-up period (Log-rank test p = 0.003). Alterations in ΔCystatin C levels pre and post-RFCA in the initial phase could independently predict the recurrence of AF.

Clinical relevance of left atrial structural remodeling and non-pulmonary vein foci in atrial fibrillation.

The mechanistic role of left atrial (LA) structural remodeling as a non-pulmonary vein (PV) trigger in the initiation of atrial fibrillation (AF) remains uncertain. This study is aimed at prospectively evaluating the association between non-PV triggers and LA structural remodeling. A total of 517 patients undergoing catheter ablation for AF were included. After PV isolation, a standardized protocol was implemented to reveal non-PV triggers, which included burst pacing into AF followed by cardioversion during isoproterenol infusion. If pacing-induced atrial tachycardia (AT) was observed, mapping and catheter ablation were performed. The mean percentage of LA low-voltage area (LVA) < 0.5mV incrementally increased during right atrial pacing among the no induction (n = 470), AF (n = 21), and AT (n = 26) groups (2.6 ± 5.7%, 5.5 ± 6.4%, and 18.0 ± 21.5%, respectively; P < 0.001). In the AF induction group, non-PV foci originated from the left atrium in 13 of 25 foci (52%), and 8 of 13 LA non-PV foci (62%) were located in the septal region. All except 1 focus originated from the non-LVA < 0.5mV (8%), but 8 of the 13 LA foci originated from the LVA < 1.0mV (62%). There were no differences in AF recurrence among the groups (log-rank, P = 0.160). The majority of non-PV foci in the LA originated outside regions with advanced structural remodeling, thus suggesting the limited effectiveness of adjunctive ablation guided by the LVA < 0.5mV during sinus rhythm in eliminating non-PV triggers.

Is sinus rhythm maintenance after repeat catheter ablation effective in patients with atrial fibrillation and heart failure with preserved ejection fraction?

Heart failure (HF) with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) are associated with high morbidity and mortality. Recently, sinus rhythm (SR) maintenance (SRM) after catheter ablation (CA) of AF (AFCA) in HFpEF has shown to reduce adverse events as compared to medical treatment. However, it remains unclear whether SRM after a repeat CA for recurrent AF has the same effect as SRM after the initial CA in patients with AF and HFpEF. We studied 244 AF patients with HFpEF who maintained SR after repeat AFCA (repeat CA-SRM group, n = 54) and initial AFCA (initial CA-SRM group, n = 190). HFpEF were defined as HFA-PEFF score of 5 or 6 and left ventricular ejection fraction ≥ 50% before the initial CA. The primary endpoint was a composite of all-cause mortality, HF hospitalizations, or strokes within 3 years after the initial or repeat CA. The incidence of the primary endpoint was similar between the repeat CA-SRM and initial CA-SRM groups (3 of 54 [5.6%] vs. 8 of 190 [4.2%], p = .423 by a log-rank test). There was no significant difference in the 12-month HFA-PEFF score and the proportion of a 12-month HFA-PEFF score <5 between the repeat CA-SRM and the initial CA-SRM groups (5 [4,6] vs. 5 [4,6], p = .915, and 46% vs. 35%, p = .426, respectively). In patients with AF and HFpEF diagnosed by HFA-PEFF score, the primary endpoint of all-cause mortality, HF hospitalizations, and strokes was similar between the repeat CA-SRM and initial CA-SRM groups.

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

Atrial fibrillation (AF) inducibility with burst pacing (BP) after radiofrequency ablation (RFA) has been reported to be associated with AF recurrence. In contrast, the relevance of inducibility and recurrence after cryoablation (CRA) is unclear. We investigated 367 patients undergoing initial ablation for paroxysmal AF (RFA: 174, CRA: 193). Propensity score matching was conducted, retaining 134 patients in each group. Following pulmonary vein isolation (PVI), the inducibility by BP was tested. Inductions at 250ppm were defined as low-frequency burst pacing (LFBP) positive, and those at 300ppm were classified as medium-frequency burst pacing (MFBP) positive. They were followed for 600days. Forty-eight patients (18%) had AF recurrence. There was no significant difference in the recurrence rate between RFA and CRA (17% vs. 19%, Log-rank p=0.79). In RFA, significant differences were observed for both LFBP (Log-rank p<0.001) and MFBP (Log-rank p<0.001). In contrast, in CRA, there were no significant differences for either LFBP (Log-rank p=0.39) or MFBP (Log-rank p=0.19). Multivariable analysis revealed that LFBP-positive (hazards ratio [HR]=5.75, 95% confidence interval [CI] 2.41-13.7, p<0.001) was an independent predictor for recurrence with RFA. Acute reconnection (HR=2.73, 95% CI 1.13-6.56, p=0.025) was an independent predictor for recurrence with CRA. The inducibility by BP after RFA predicted recurrence at both low and medium frequencies. LFBP-positive was an independent predictor of recurrence in multivariable analysis. In contrast, the inducibility by BP after CRA was not a predictor of recurrence. This study did not require clinical trial registration.