Recurrent Symptomatic Atrial Fibrillation Research Articles

Optimized workflow for pulmonary vein isolation using very high power short duration radiofrequency ablation

Abstract Background Point-by-point radiofrequency ablation is the most used invasive treatment of atrial fibrillation (AF). However, single-shot technologies are largely widespread due to their proved safety and efficacy. QDOT MICRO (QDM) is a novel contact force–sensing catheter optimized for temperature-controlled radiofrequency (RF) ablation that allows to maintain target temperature during 90 W ablations for ≤4 seconds. Purpose This study evaluates procedural safety and effectiveness as well as long-term effects of an optimized procedural workflow using QDM catheter to perform wide atrial circumferential ablation in patients with paroxysmal AF. Methods Consecutive patients referred for paroxysmal AF first ablation through pulmonary vein isolation (PVI) were prospectively enrolled. Every procedure was performed in general anesthesia by using CARTO3 Electroanatomical Mapping System BiosenseWebster QDM catheter and Deflectable Sheet VIZIGO as single sheet in left atrium. VHPSD was performed to encircling the posterior wall, while conventional-power temperature-controlled (CPTC) mode was used to encircling the anterior wall. The primary safety endpoint was incidence of primary adverse events within ≤7 days of ablation. The primary effectiveness endpoint was freedom from documented atrial tachyarrhythmia recurrence and acute procedural, repeat ablation, and antiarrhythmic drug failure. Results 120 enrolled participants (61 ± 12 years, 45% female) met eligibility criteria. Median procedural skin-to-skin time and RF application for ablating PVs were 56 and 17 minutes, respectively. Median ablation time was 22 minutes. First-pass isolation (entrance and exit block validation) was obtained in 98 % and inter-lesion distance was 4,8 ± 0,8 mm. In 100% of patients PVI was obtained without adverse events. The Kaplan-Meier estimated 12-month rate for clinical success (freedom from symptomatic recurrence of AF) was 93%, freedom from AF was 89% Conclusions PVI performed with point by point optimized workflow using VHPSD RF catheter in combination with steerable sheet is highly efficient and effective without compromising safety.

Multicenter retrospective evaluation of a patient-tailored electrogram-based ablation strategy using an artificial intelligence software in repeat atrial fibrillation ablation procedures

Abstract Background While pulmonary vein isolation (PVI) is the gold standard approach of treatment of atrial fibrillation (AF), the optimal strategy in case of AF recurrences for redo patients is not well established. Several studies described the usefulness of ablating in atrial regions exhibiting abnormal electrograms, i.e. spatio-temporal dispersion, during AF and an artificial intelligence (AI) electrograms (EGMs)-based software solution has been developed and validated to obtain real-time adjudications of multipolar electrograms in de novo patients. Purpose This study sought to evaluate the novel AI-EGMs-based software approach for redo-AF ablation procedures. Methods This study was a retrospective, multicentric, nonrandomized study. Patients with recurrent symptomatic AF were enrolled in 7 European centers. Redo ablation procedures were performed using the AI software and acute and long-term outcomes after ablation were evaluated. Results A total of 117 patients with refractory symptomatic AF admitted for redo procedure were included with 30% paroxysmal, 42% short-standing persistent and 28% long-standing persistent AF at the time of the redo procedure. During the index procedures, a previous PVI ablation was performed in all patients while additional ablation such as lines and EGM-based ablation was performed in 64 patients (55%). Out of 117 patients, 30 (26%) presented with structural heart disease, 61 (52%) with hypertension, 31 (26%) with a BMI >30, 16 (14%) a sleep apnea syndrome and 24 (20%) had an antiarrhythmic treatment at the time of the procedure. The average AF history was 6.54 ± 4.15 years with an average sustained duration equal to 25 ± 62 months. AI-EGMs-based AF ablation was performed in all patients and easily integrated in the physicians’ workflow during redo procedures. AF termination, i.e. AF regularization or sinus rhythm conversion, occurred in 82/117 patients (71%) with sinus rhythm conversion by ablation in 79/117 patients (68%). After a mean follow-up of 11 ± 5 months, 81% of patients were free from documented AF, with or without antiarrhythmic drugs (AADs) after one redo procedure and 60% of patients were free from any documented atrial arrhythmia, with or without AADs, after one redo procedure per patient. Furthermore, we observed that 77%, 84% and 82% of patients were free from documented AF with or without AADs in paroxysmal, short-standing and long-standing persistent AF patients respectively, and that 71%, 59% and 49% of patients were free from any documented atrial arrhythmia with or without AADs in paroxysmal, short-standing and long-standing persistent AF patients respectively. Conclusions This retrospective study reports that patient-tailored spatiotemporal dispersion ablation is a relevant and standardized approach for repeat AF ablation. This was obtained with an AI-EGMs-based software solution, which may be added to the operative workflow of redo AF procedures.

Treatmen of atrial fibrillation with cryoballoon pulmonary vein isolation - results of a 5-year follow-up

Abstract Background Atrial fibrillation is the most common arrhythmia in the general population and cryoballoon ablation is gradually becoming a first-line treatment. However, data regarding long-term outcomes after this procedure are still lacking. Aim The goal was to show the results of a long-term follow-up following the cryoballoon pulmonary vein isolation in patients with atrial fibrillation (AF). Methods A total of 126 patients were included in the study of which 77.0% had paroxysmal atrial fibrillation (PAF). Successful treatment outcome was defined as AF recurrence-free survival with stabile sinus rhythm during 5 years after the procedure. A treatment failure was defined as symptomatic AF recurrence with ECG verification (12 lead ECG or AF lasting >30s by Holter EKG). The patients on antiarrhythmic therapy and those who underwent a redo pulmonary vein isolation procedure were also included. Results Following cryoballoon pulmonary vein isolation in a 5-year period 52.4% of patients were in stable sinus rhythm without AF recurrence. With redo pulmonary vein procedures a total of 61.9% of patients were without AF recurrence. Together with antiarrhythmic drugs 57.9% of patients were in sinus rhythm without AF recurrence in a 5-year period. With redo pulmonary vein isolation and antiarrhythmic drugs a total of 73.8% of patients were without AF recurrence. There was a statistically significant difference regarding AF recurrence between patients who underwent redo pulmonary vein isolation and those who did not (p=0.006). In patients with PAF, 62.9% remained without AF recurrence, and 79.4% underwent a redo procedure. In patients with persistent atrial fibrillation (PersAF), 41.4% were without AF recurrence, and 55.1% underwent a redo procedure. The difference between PAF and PersAF was statistically significant (p=0.009). Conclusion Data from our center show good long-term results of cryoballoon pulmonary vein isolation in patients with atrial fibrillation. The procedure is especially successful in patients with PAF.1 The use of redo procedures is justified as it increases the long-term success rate.

Temperature to time Catch-Up: a novel procedural endpoint to predict durable pulmonary vein isolation after cryoballoon ablation of paroxysmal atrial fibrillation.

Cryoballoon ablation is a widely used single-shot technique for pulmonary vein isolation (PVI) in the treatment of paroxysmal atrial fibrillation (AF). Procedural endpoints ensuring maximal PVI durability are important. To assess the performance of cryoablation procedural markers to predict long-term PVI. In a single center, consecutive patients who underwent redo ablation with high-density mapping for symptomatic AF recurrence after cryoballoon ablation were included and cryoballoon procedural data were collected, including temperature values at 30 and 60s, time to isolation, nadir temperature and the velocity of temperature decline estimated with the temperature/time catch-up point (T2T-Catch-Up) defined as positive when the freeze temperature in minus degree equals the time in seconds after cryoablation initiation (e.g. -15°C in the first 15s of the ablation impulse). 47 patients (62% male; 58.3 ± 11.2years) were included. Overall, 38 (80.9%) patients had ≥ 1 reconnected PV. Among 186 PVs, 56 (30.1%; 1.2 per patient on average) were reconnected. Univariate analysis revealed T2T-Catch-Up in 103 (56%) and more frequent in durably isolated than in reconnected PVs (93 [72%] vs 10 [19%], p < 0.0001). Among binary endpoints, T2T-Catch-Up had the highest specificity (82%) and predictive value for durable PVI at redo ablation (90%). In multivariable analyses, absence of T2T-Catch-Up (Odds-ratio 0.12, 95% CI [0.05-0.31], p < 0.0001) and right superior PV (Odds-ratio 3.14, 95% CI [1.27-7.74], p = 0.01) were the only variables independently associated with PV reconnection. T2T-Catch-Up, a new and simple cryoballoon procedural endpoint demonstrated excellent predictive value and strong statistical association with durable PVI.

Does the efficacy of redo AF-ablation depend on the method used in the index procedure?

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulmonary vein isolation (PVI) using cryoballoon (CB) ablation has comparable efficacy and safety compared to radiofrequency ablation (RFA) for first procedure treatment of symptomatic atrial fibrillation (AF). Redo procedures are usually done with RFA, allowing for selective pulmonary vein re-isolation as well as formation of additional lesion sets. It is unclear whether a combination of different ablation methods in the index procedure and the redo procedure provides an efficacy benefit compared to the use of RFA in both procedures. Purpose We aimed to compare the efficacy and procedural characteristics of redo AF-ablation-procedures in terms of the technology used in the first ablation procedure (Cryo vs. RFA). Methods We performed a retrospective analysis of our internal AF ablation registry, containing 310 consecutive patients that underwent a second ablation procedure for recurrence of symptomatic AF from November 2019 to August 2022. For 36 patients the method in the first procedure was unknown or a method alternative to RFA or Cryo was used, leaving 274 patients for analysis. Patients were stratified into two groups, based on the technology used in the index procedure (Cryo vs. RFA). Patients underwent follow-up at 3 and 12 months (at 12 months blanking phase recurrences were excluded), either as part of a prescheduled visit or via telephone call to the primary care provider or to the patient. Results 139 patients underwent the index PVI using RFA vs. 135 patients in which the index procedure was performed with Cryo. Baseline characteristics including sex (37.4% vs. 48.9% female, p=0.055), mean age (68.9 ± 9.7 vs. 68.7 ± 10.9 years, p=0.915), BMI (26,8 ± 4.1 vs. 28.4 ± 4.3 kg/m2. p=0.345), percentage of patients with paroxysmal AF (38.9% vs. 32.6%, p=0.280), arterial hypertension (69.6% vs. 67.4%, p=0.762), beta blocker use (84.1% vs. 80.7% p=0.472), class Ic or III antiarrhythmic drug use on discharge (40.3% vs. 45.9%, p=0.346) and mean left atrial diameter (39.7 ± 5.7 mm vs. 39.9± 5.6 mm. p=0.731) were all similar between groups. In the redo procedures, pulmonary vein reisolation was performed in 85.2% vs. 78.6% (p=0.204) after RFA vs. after Cryo. Additional substrate modifications including lines and defragmentation of low voltage potentials were done in 26.6% vs. 34.1% patients (p=0.179). Procedural duration (147.2 (110-180) vs. 139.0 (100-160) min, p=0.501), fluoroscopy time (12.1 (8.2-17.0) vs. 13.1 (8.2-19.0), p=0,638), and fluoroscopy dose (2525 (1425-3935)vs. 2544 (1356-4840) mGycm2, p=0.806) were comparable between groups. The rates of AF recurrence at 3 month follow-up (27.0% vs. 26.4%, p=0.924) and 12 month follow-up (25.6 vs. 34.5%, p=0.257) were similar between groups. Conclusion In this single center retrospective analysis, there was no difference in efficacy and procedural characteristics of redo AF-ablation-procedures based on the ablation method used in the index procedure.

Pulsed-field ablation based pulmonary vein isolation: reconnection pattern and comparison to cryoballoon ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulsed-field ablation (PFA) integrated into a pentaspline catheter is a novel single shot device to perform pulmonary vein isolation (PVI) for treatment of atrial fibrillation (AF). While initial data demonstrated high safety and efficacy, long-term PVI durability and reconnection patterns are unknown. Here, we analyzed findings from repeat ablation procedures after index PFA compared to cryoballoon ablation (CBA) based PVI. Methods We prospectively included consecutive patients with index PVI applying PFA (n=161) or CBA (n=302) who underwent repeat ablation due to symptomatic recurrence of AF or atrial tachycardia (AT) after a blanking period of 3 months. All repeat procedures were performed with a 3D mapping system and RF energy. Results We identified a total of 14 patients after previous PFA and 23 patients after previous CBA. PV reconnection was detected in 9/14 (64%) patients after PFA and in 16/23 (70%) after CBA (p=1.000). A total of 24/55 (44%) vs. 34/92 (37%) initially isolated PVs demonstrated electrical reconduction (p=0.487) after PFA and CB ablation. In both groups the right inferior PV was reconnected most frequently (9/24 (38%) patients after PFA and 10/34 (29%; p=0.578) patients after CBA). Distribution of conduction gaps is shown in figure 1. All PVs were successfully reisolated. Repeat procedures after index PFA and CBA showed similar duration (115±32 min vs. 114±49 min; p=0.785), fluoroscopy time (13±4 min vs. 14±8 min; p=0.558) and number of RF applications (38±23 vs. 36±34, p=0.738). Conclusion During repeat AF/AT ablation after previous PFA- or CBA-based PVI a comparable incidence of PV reconduction gaps was found. Repeat procedure times and fluoroscopy exposure were similar. Randomized controlled trials and longer follow-up are necessary to draw further conclusions.

Association of iron deficiency with atrial fibrillation recurrence after pharmacological cardioversion

Aim. This study aims to assess the association between iron deficiency (ID) and recurrences of atrial fibrillation (AF) in patients after pharmacological cardioversion with amiodarone within 12 months.Material and methods. The open-label, prospective, single-center study included 198 patients with non-valvular paroxysmal AF after successful pharmacological cardioversion with amiodarone. Group I included 116 patients with ID, and group II — 82 patients with normal iron status. The primary end-point of the study was the development of symptomatic AF recurrences within 12 months after the cardioversion which was estimated by the Kaplan-Meier method. The differences were considered statistically significant if p-value was &lt;0,05.Results. Absolute ID was found in patients of group I; anemia was revealed in 85,3% of the patients. The groups did not differ in basic clinical and demographical parameters, concomitant diseases and drug therapy. Along with that, the I group patients were older (the median was 73 (64,8-79) years old and 69 (63-75) years old, respectively, р=0,008), and their left ventricular mass was larger (the median was 145 (115-176) g and 132,5 (118,2-145) g, respectively, р=0,004). The sinus rhythm restoration in group I required less dose of amiodarone (the median was 450 (300-600) mg and 1000 (600-1200) mg, respectively, р&lt;0,001) and less time from the start of the drug administration to the rhythm restoration (the median was 7 (3-10) and 12 (9-18) hours, respectively, р&lt;0,001). During the 12-month follow-up period, 49 (42,2%) patients in group I and 16 (19,5%) patients in group II developed AF recurrences (р=0,0008), hazard ratio 2,64 (95% confidence interval: 1,5-4,65) (р=0,0003).Conclusion. ID is associated with the increase of the number of symptomatic AF recurrences in patients after pharmacological cardioversion with amiodarone within 12 months.

Persistent Atrial Fibrillation in Elderly Patients: Limited Efficacy of Pulmonary Vein Isolation.

(1) Background: Cryoballoon pulmonary vein isolation (cryoPVI) is established for symptomatic paroxysmal atrial fibrillation (AF) treatment, but its value in persistent AF is less clear. In particular, limited data are available on its efficacy in elderly patients (≥75 years) with persistent AF. Age is an important modifier of AF progression and represents a risk-factor for AF recurrence. (2) Methods: Prospective, single-center observational study to evaluate the impact of age on efficacy and safety of cryoPVI in elderly patients. Primary efficacy endpoint was symptomatic AF recurrence after 90-day blanking period. Primary safety endpoints were death from any cause, procedure-associated complications or stroke/transient ischemic attack. Median follow-up was 17 months (range 3–24). (3) Results: We included 268 patients with persistent AF (94 ≥ 75 years of age). Multivariate Cox regression analysis identified age as the only independent factor influencing AF recurrence in the overall cohort (p = 0.006). To minimize confounding bias in efficacy and safety analysis of cryoPVI, we matched younger and elderly patients with respect to baseline characteristics. At 24 months, primary efficacy endpoint occurred in 13/69 patients <75 years and 31/69 patients ≥75 years of age (24 months Kaplan–Meier event-rate estimates, HR 0.34; 95% CI, 0.19 to 0.62; log-rank p = 0.0004). No differences were observed in the occurrence of safety end points. (4) Conclusions: Elderly (≥75 years) patients with persistent AF undergoing cryoPVI had an approximately threefold higher risk of symptomatic AF recurrence than matched younger patients. Accordingly, other treatment modalities may be evaluated in this population.

Bayesian network meta-analysis comparing cryoablation, radiofrequency ablation, and antiarrhythmic drugs as initial therapies for atrial fibrillation.

Antiarrhythmic drugs (AADs) and catheter ablation are first line treatments of paroxysmal atrial fibrillation (PAF), however, there exists a paucity of data regarding the potential benefit of different catheter ablation technologies versus AADs as an early rhythm strategy. To assess the safety and efficacy of cryoablation versus radiofrequency ablation (RFA) versus AADs as a first line therapy of PAF. MEDLINE, Embase, Scopus and CENTRAL were searched to retrieve randomized clinical trials (RCTs) comparing cryoablation, RFA or AADs to one another as first line therapies for atrial fibrillation (AF). The primary outcome was overall freedom from arrhythmia recurrence (AF, atrial flutter [AFL], atrial tachycardia). Secondary outcomes included freedom from symptomatic arrhythmia recurrence, hospitalization, and serious adverse events. A random-effects Bayesian network meta-analysis was used to calculate odds ratios (OR) and 95% credible intervals (CrI). Six RCTs (N = 1212) met the inclusion criteria (605 AADs, 365 Cryoablation, and 245 RFA). Compared with AADs, overall recurrence was reduced with RFA (OR: 0.31; 95% CrI: 0.10-0.71) and cryoablation (OR: 0.39; 95% CrI: 0.16-1.00). Comparing ablation (cryoablation and RFA) with AADs in respect to freedom from symptomatic AF recurrence, neither cryoablation (OR: 0.35; 95% CrI: 0.06-1.96) nor RFA (OR: 0.34; 95% CrI: 0.07-1.27) resulted in statistically significant reductions individually compared to AADs, though pooled ablation with both technologies showed lower odds of arrhythmia recurrence (OR: 0.35; 95% CrI: 0.13-0.79). In terms of serious adverse events rates, neither cryoablation (OR: 0.77; 95% CrI: 0.44-1.39) nor RFA (OR: 1.45; 95% CrI: 0.67-3.23) were significantly different to AADs. RFA resulted in a statistically significant reduction in hospitalizations compared to AAD (OR: 0.08; 95% CrI: 0.01-0.99), whereas cryoablation did not (OR: 0.77; 95% CrI: 0.44-1.39). The surface under the cumulative ranking curve showed RFA to be the most effective treatment at reducing overall rates of recurrence, symptomatic recurrence and hospitalizations; whereas cryoablation was most likely to reduce serious adverse events. Cryoablation and RFA are both effective and safe first line therapies for AF compared to AADs, with RFA being the most effective at reducing recurrences.

Anticoagulation, therapy of concomitant conditions, and early rhythm control therapy: a detailed analysis of treatment patterns in the EAST - AFNET 4 trial.

AimsTreatment patterns were compared between randomized groups in EAST-AFNET 4 to assess whether differences in anticoagulation, therapy of concomitant diseases, or intensity of care can explain the clinical benefit achieved with early rhythm control in EAST-AFNET 4.Methods and resultsCardiovascular treatment patterns and number of visits were compared between randomized groups in EAST-AFNET 4. Oral anticoagulation was used in >90% of patients during follow-up without differences between randomized groups. There were no differences in treatment of concomitant conditions between groups. The type of rhythm control varied by country and centre. Over time, antiarrhythmic drugs were given to 1171/1395 (84%) patients in early therapy, and to 202/1394 (14%) in usual care. Atrial fibrillation (AF) ablation was performed in 340/1395 (24%) patients randomized to early therapy, and in 168/1394 (12%) patients randomized to usual care. 97% of rhythm control therapies were within class I and class III recommendations of AF guidelines. Patients randomized to early therapy transmitted 297 166 telemetric electrocardiograms (ECGs) to a core lab. In total, 97 978 abnormal ECGs were sent to study sites. The resulting difference between study visits was low (0.06 visits/patient/year), with slightly more visits in early therapy (usual care 0.39 visits/patient/year; early rhythm control 0.45 visits/patient/year, P < 0.001), mainly due to visits for symptomatic AF recurrences or recurrent AF on telemetric ECGs.ConclusionThe clinical benefit of early, systematic rhythm control therapy was achieved using variable treatment patterns of antiarrhythmic drugs and AF ablation, applied within guideline recommendations.

B-PO04-203 CARDIOVASCULAR HEALTHCARE UTILIZATION IN PERSISTENT ATRIAL FIBRILLATION PATIENTS ABLATED WITH A CONTACT FORCE CATHETER

The Persist-End trial was conducted to demonstrate that RF ablation with a magnetic sensor enabled optical contact force sensing ablation catheter was safe and effective for the treatment of drug-refractory, recurrent symptomatic persistent atrial fibrillation (PersAF). Additional analyses were conducted to quantify the impact of RF ablation on healthcare utilization and Quality of Life post-ablation in PersAF patients. In the prospective, single-arm, multi-center investigational device exemption PersistEnd clinical trial, cardiovascular healthcare utilization (cvHCU), defined as cardiovascular events resulting in hospitalization or emergency room use, was analyzed using patients as their own controls. Differences in annualized event rates (EPPY) of cvHCU were compared pre- and post-ablation using a nonparametric bootstrap method and further compared in patients stratified by the study effectiveness endpoint of ablation success. Utility-Index Scores based on EQ-5D-5L at baseline were compared across the 15-month follow-up period using paired t-test. A total of 223 PersAF patients (mean age 65.4 ± 10.1 ys, 69.1% male, 95.5% white) received ablation between Nov 2018-Sept 2019. In the 1-year pre-ablation period, 69 (30.9%) patients had 103 cvHCU (0.46 EPPY). These events reduced to 0.35 EPPY (24% reduction, p = 0.15) post-ablation. This reduction was observed in 93.8% of bootstrap simulations. Out-patient visits reduced significantly from 0.46 EPPY to 0.21 EPPY (55% reduction, p < 0.001) over the follow-up period. Subjects that passed the primary endpoint of the trial had 52% reduction in cvHCU (p = 0.02). Average EQ-5D-5L Utility-Index Scores improved from 0.86 at baseline to 0.93 (p < 0.05) at 15 months. The change in resource use before and after ablation highlights effectiveness of the therapy in reducing cardiovascular related healthcare encounters. Increases in the Utilities-Index highlight the improved quality of life that may also accompany RF ablation of PersAF.

Efficacy and Safety of SATAKE HotBalloon® Catheter for Treatment of Paroxysmal Atrial Fibrillation - A Post-Marketing Surveillance Study.

SATAKE HotBalloon®catheter (HBC) is a radiofrequency balloon catheter for the treatment of atrial fibrillation (AF), and was approved for use in Japan to treat drug-resistant paroxysmal AF in 2015. Post-marketing surveillance study was conducted by Toray Industries, Inc. to evaluate the efficacy and safety of HBC treatment in patients with paroxysmal AF in a real-world setting. This study is the first nation-wide survey of HBC treatment for paroxysmal AF in clinical practice in Japan.Methods and Results:This was a single-arm, multicenter observational study with an observation period of 48 weeks after ablation. Pulmonary vein isolation and AF non-recurrence rates were evaluated and adverse events (AEs) were observed at 46 sites in Japan. An AF event was defined as recurrence of AF or re-ablation from 12 to 48 weeks after ablation. The success rate of pulmonary vein isolation was 99.0% (486/491) for patients with AF. The cumulative AF non-recurrence rate was 94.1% at 24 weeks and 87.8% at 48 weeks. AEs were found to occur 21.5% (114/530), and ablation-related AEs were found to occur 2.6% (14/530) during the study period, with the most common being pericardial effusion (0.8%, 4/530). This study demonstrates the efficacy and safety of HBC ablation in Japanese patients with recurrent symptomatic paroxysmal AF refractory to antiarrhythmic therapy.

Impact of initial rhythm control with cryoballoon ablation versus drug therapy on atrial fibrillation recurrence and quality of life: results from the Cryo-FIRST study

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Medtronic OnBehalf The Cryo-FIRST Investigators Background Cryoballoon ablation (CBA) as a first-line rhythm control strategy is superior to antiarrhythmic drugs (AADs) for preventing atrial arrhythmia recurrence; however, the impact of first-line CBA specifically on atrial fibrillation (AF) recurrence and quality of life (QoL) has not been well characterized. Purpose To compare AF recurrence and QoL following first-line CBA vs. AAD therapy in patients with paroxysmal AF within the CryoFIRST trial (NCT01803438). Methods Patients with recurrent symptomatic paroxysmal AF who had not been administered class I or III AAD therapy for &amp;gt;48 hours were enrolled at 18 sites in 9 countries. Patients were randomized (1:1) to CBA or AAD treatment (Class I or III). Subjects were followed by 7-day Holter at 1, 3, 6, 9, and 12 months. Time-to-first AF recurrence outside of a 90-day blanking period was estimated by Kaplan-Meier analysis. QoL was evaluated using the Atrial Fibrillation Effect on Quality of Life (AFEQT) and 36-Item Short Form Health Survey (SF-36) v2 questionnaires. Results Of the 218 randomized subjects, 187 (86%) completed the 12-month follow-up. By intention-to-treat (ITT) analysis, freedom from AF after blanking was achieved in 86.6% in the CBA and 74.5% in the AAD group (p = 0.023). There was no difference in the time-to-first serious adverse event between groups. In total, 84.3% of patients in the CBA vs. 75.0% of patients in the AAD arm had a clinically important improvement (≥5 points) in the AFEQT summary score. The adjusted mean difference in the AFEQT summary score at 12 months was 9.9 points higher in the CBA group (95% CI: 5.5-14.2; P &amp;lt; 0.001). All AFEQT subscale scores were more favorable in the CBA vs. AAD group at 12 months. There were no significant group differences in any of the SF-36 health domain scores at 12 months in the ITT analysis. In the per-protocol analysis, clinically important and significant group differences in favor of CBA were observed at 12 months for 3 of 8 SF-36 health domain scores (physical functioning, general health and social functioning). Conclusion CBA is superior to AAD for preventing AF recurrence and improving AF-specific QoL in patients with paroxysmal AF. AFEQT Scores at Baseline and 12 MonthsAFEQT Score, Mean ± Standard DeviationCBAAADAdjusted Mean Difference at 12 Months (CBA vs. AAD)p-valueBaseline12 MonthsBaseline12 MonthsDaily Activities65.3 ± 25.887.8 ± 17.161.0 ± 27.976.6 ± 25.48.9 (3.2-14.6)0.002Symptoms59.9 ± 24.888.8 ± 15.658.4 ± 25.280.9 ± 22.27.1 (1.5-12.7)0.014Treatment Concern59.9 ± 23.189.8 ± 14.060.4 ± 24.577.7 ± 22.212.7 (7.9-17.5)&amp;lt;0.001AFEQT, Atrial Fibrillation Effect on Quality of Life questionnaire. CBA, cryoballoon ablation. AAD antiarrhythmic drug.Abstract Figure. Freedom From Atrial Fibrillation

Electrical cardioversion during cryoballoon pulmonary vein isolation predicts long-term ablation success in persistent atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background Cryoballoon pulmonary vein isolation (cryoPVI) is an established option for treatment of atrial fibrillation (AF) but many periprocedural events influencing long-term outcome and procedural safety of ablation remain unclear. In radiofrequency ablation studies, failure to convert to sinus rhythm and electrical cardioversion (ECV) have been associated with increased recurrence rates. In this context, the influence of ECV during cryoPVI on long-term ablation efficacy is unclear. Objective A prospective comparison of AF recurrence after cryoballoon ablation in patients who were in AF or atrial tachycardia at the beginning of cryoPVI requiring ECV during procedure with patients who underwent ablation therapy without ECV. Methods We analyzed consecutive patients who underwent cryoPVI in a single-center cohort between 2018 and 2020. Follow-up was performed at 3, 6, 12, 18 and 24 months after ablation. Primary endpoints were: symptomatic AF recurrence for efficacy and bleeding, phrenic nerve injury, stroke or death for safety. Results 472 consecutive patients who underwent ablation in a single-center cohort were analysed. Mean follow-up time was 15 months. In 195 patients (74 paroxysmal AF vs. 121 persistent AF, age 69 ± 10 years, 57% male, CHA2DS2-VASc 2.6 ± 1.4) at least one ECV was performed following ablation, while no cardioversion was necessary in 277 patients (214 paroxysmal AF vs. 63 persistent AF, age 69 ± 10 years, 55% male, CHA2DS2-VASc 2.7 ± 1.5). After 24 months, primary efficacy endpoint occurrence was significantly higher in persistent AF requiring cardioversion during procedure than for persistent AF without cardioversion and paroxysmal AF with/ without cardioversion (56.1 % vs. 31.2%, 33.6%, 32.9%, log-rank p = 0.009, figure). Primary safety endpoint occurred in form of pericardial effusion or transient phrenic nerve injury in two patients in cardioversion group (1.0%) and three patients without cardioversion (1.1%). No deaths or strokes were observed in either group. Total procedure duration (55.6 ± 17min vs. 57.7 ± 15.9min, P = 0.17) and left-atrial dwell time (39.7 ± 14.9min vs. 42 ± 15.6min, P = 0.11) were similar. Conclusion In patients with persistent AF, the need for ECV during cryoPVI predicts a poorer long-term outcome during 2-year follow-up. Future studies should focus on this specific patient population. Abstract Figure.

Atrial Fibrillation

Atrial fibrillation (AF) is an abnormal rhythm characterized by chaotic atrial electrical activity resulting in loss of atrial contraction, an irregular and unpredictable heart rate, and a tendency for thrombus formation. The prevalence of AF is estimated at 1 to 2%, but it’s likely higher than that because one-third of patients may have no symptoms and might never seek medical attention. Data suggest that 1 in 4 people over the age of 40 will develop AF in their lifetime. About 10% of patients over age 80 have experienced the arrhythmia, and some estimates predict the prevalence will double in the next 50 years. This chapter discusses the pathophysiology, genetics, diagnosis, classification, and treatment of AF. Figures show atrial fibrillation and coarse atrial fibrillation plus common right atrial flutter. One algorithm is for oral anticoagulation therapy, and a second shows a recommended hierarchical choice of antiarrhythmic therapies versus catheter ablation for recurrent symptomatic atrial fibrillation. Tables list classification, diagnostic evaluation of, clinical consequences of, and conditions often associated with atrial fibrillation. Three scoring systems are included: 1) for congestive heart failure, hypertension, diabetes, stroke, and transient ischemic attack; 2) to assess the risk of bleeding with oral anticoagulation, and 3) data and proportion of patients from the Euro Heart Survey. Other tables include long-term anticoagulation guidelines for atrial fibrillation, intravenous drugs used for acute rate control, oral drugs used for chronic rate control, and antiarrhythmic drugs for conversion of atrial fibrillation and/or maintenance of sinus rhythm. In addition, there’s a summary of randomized trials weighing rate control and rhythm control strategies, plus schemes for categorizing thromboembolism risk. This review contains 4 highly rendered figures, 14 tables, and 129 references.

Heat Shock Protein 70 Is Associated With Cardioversion Outcome and Recurrence of Symptomatic Recent Onset Atrial Fibrillation in Hypertensive Patients.

Accumulating evidence indicates that heat shock proteins (HSPs) may represent a suitable biomarker to predict atrial fibrillation (AF). We investigated the relation of circulating serum HSP70 (sHSP70) with inflammatory cytokines and recurrence of symptomatic recent onset AF (ROAF). We enrolled 90 patients with ROAF (the duration from onset of symptoms ≤24 hours) and 30 controls. Patients received amiodarone for cardioversion and rhythm control. The association of serum HSP70, serum interleukin-2 (sIL-2), and serum interleukin-4 (sIL-4) with the presence of cardioversion and AF recurrence within a year was investigated. Toll-like receptor 4 (TLR4) signaling dependence for IL-2 and IL-4 induction in response to stimulation with HSP70 was tested in rat aortic vascular smooth muscle cell cultures. Patients had higher sHSP70 and sIL-2 and lower sIL-4 compared with controls. Serum HSP70 was independently associated with ROAF (P = 0.005) and correlated with sIL-2 (r = 0.494, P < 0.001) and sIL-4 (r = -0.550, P < 0.001). By 48 hours, 71 of the 90 patients were cardioverted, with noncardioverted patients having higher sHSP70 and sIL-2 and lower sIL-4, which were the only independent factors associated with cardioversion. AF recurred in 38 of the 71 cardioverted patients in 1 year. A cutoff value of sHSP70 ≥0.65 ng/mL and sIL-2 ≥0.21 pg/mL was the only independent factor associated with AF recurrence (hazard ratio: 3.311, 95% confidence interval: 1.503-7.293, P = 0.003 and hazard ratio: 3.144, 95% confidence interval: 1.341-7.374, P = 0.008, respectively). The exposure of smooth muscle cell to HSP70 in vitro increased the expression of IL-2 (5×) and IL-4 (1.5×) through TLR4-dependent and receptor-independent mechanisms. In conclusion, sHSP70 and sIL-2 might constitute a prognostic tool for determining the cardioversion and recurrence likelihood in ROAF.

Effect of beta-blocker-induced heart rate lowering on left atrial function in patients with hypertension and recurrent atrial fibrillation

Abstract Background The ESC/ESH Hypertension Guidelines identify high resting heart rate (HR) as a risk factor in patients with hypertension. However, it is not known, whether pharmacological reduction in HR is associated with improvement of prognosis in patients with preserved ejection fraction. In retrospective studies beta blockers (BBs) use was associated with impaired left atrial (LA) function in hypertension, but the prospective data, concerning this relationship is scarce. Purpose To assess the effects of HR reduction with BBs on LA function in hypertensive patients with recurrent (rare paroxysms) mild symptomatic atrial fibrillation. Methods Open prospective trial included 91 patients with hypertension, elevated heart rate (≥80 bpm) and recurrent atrial fibrillation (EHRA 2A or less) with rare paroxysms to receive BBs with a target HR (sinus rhythm) of less or greater than 70 bpm. All the patients underwent an echocardiogram at baseline and at the end of the study. Conventional echo measures and extended LA measures, including the minimal and maximal LA volumes (LAVmin and LAVmax) and LA emptying fraction (LAEF) were performed. Patients were followed for 4 months on the change and assessed for primary endpoint of median LAEF measurement at the end of the study. Results 47 patients were randomized to group with a target HR of ≤70 bpm and 44 patients to &amp;gt;70 bmp. Among them, 44 and 41 patients completed the study (2 had AF at the final visit; 4 were lost to follow-up). Baseline median HR was 77 (75; 80) bpm. After 4.4 months of treatment, median HR was 62 (60; 67) bmp in ≤70 group and 73 (72; 76) bpm in &amp;gt;70 group (p&amp;lt;0.001). There were no intergroup differences in antihypertensive therapy and systolic (129 vs 130 mmHg; p=0.32) and diastolic (78 vs 78 mmHg; p=0.53) blood pressure. At the end of the study patients in ≤70 group had significantly lower LAEF compared with &amp;gt;70 group (37 vs 42%; p=0.01); a median change was −6.5 (−9.75; −3.9)% and −0.27 (−1.78; 1.18)%, respectively [estimated between group difference −5.89%; 95% confidence interval (CI): −8.06 to −3.71%]. Despite similar indices of LAVmin (22 vs 19 ml/m2; p=0.66) and LAVmax (38 vs 37 ml/m2), comparison of changes showed significant differences: median change LAVmin: 1.3 ml/m2 in ≤70 vs 0.5 ml/m2 in &amp;gt;70 groups (estimated between group difference −1.29%; 95% CI: −2.07 to −0.5%) and ΔLAVmax: 1.8 ml/m2 in ≤70 vs 1 ml/m2 in &amp;gt;70 groups (estimated between group difference −1.51%; 95% CI: −2.73 to −0.28%). E/E' and left ventricle mass index did not differ between study groups at the end of the study, but E' was significantly lower in the ≤70 group (7 vs 8.3 cm/s; p=0.04). Conclusion BB-induced HR lowering with a target ≤70 bpm significantly reduced LA function as compared to lenient target HR (&amp;gt;70 bpm). Although elevated HR is associated with adverse outcomes in patients with hypertension, excess HR lowering with BBs might not be beneficial in this group. Funding Acknowledgement Type of funding source: None

Who is too old for epicardial fat volume quantification?

Abstract Introduction Epicardial adipose tissue has been implicated in the pathophysiology of atrial fibrillation (AF) and was recently shown to be an independent predictor of AF relapse rate and severity after pulmonary vein isolation (PVI). However, its impact in older patients hasn't been analyzed. The aim of this study was to assess the relative importance of pericardial fat in an older population of patients undergoing pulmonary vein isolation (PVI). Methods Single-center retrospective study of symptomatic drug-resistant AF patients undergoing PVI from November/2015 to June/2019. Baseline demographics, clinical and imaging data including cardiac CT and clinical outcomes were collected and analyzed. Population was dichotomized according to age above or below 70 years of age and groups were compared. Epicardial fat volume was quantified by contrast-enhanced cardiac CT using a semi-automated method. The study endpoint was symptomatic and/or documented AF recurrence after a 3-month blanking period. Results We assessed 575 patients (354 males, mean age 61±11 years, 449 paroxysmal AF), 145 of which were 70 or older. Compared to the younger cohort, these patients had an higher prevalence of women, lower BMI (27 kg/m2 [IQR 24–30] vs 28 kg/m2 [IQR 25–30] kg/m2, p=0.012), higher CHA2DS2-VASc score (3 [IQR 2–4] vs 1 [IQR 1–2], p&amp;lt;0.001) and larger indexed left atrial volumes (61mL [IQR 52–84] vs 54mL [IQR 47–66], p&amp;lt;0.001). Median epicardial fat volume was 2.96 cm3/m2 [IQR 2.99–4.00] in the overall population and was higher in older patients (HR 2.21 cm3/m2 [IQR 1.44–3.17] vs HR 1.87 cm3/m2 [IQR 1.24–2.90]; p=0.016). During follow-up, 232 patients relapsed (40%), with similar recurrence rates between younger and older patients (40% vs 42%, p=0.63) according to Kaplan-Meier survival curve analysis (HR 1.10, 95% CI 0.82–1.48; log-rank p=0.519). Epicardial fat volume remained an independent predictor of AF relapse in the older subset of patients (HR 1.06 for every 1 cm3/m2 increase in epicardial fat volume [95% CI 1.28–2.00]; p&amp;lt;0.001), as did the presence of non-paroxysmal AF (HR 2.78 [95% CI 1.48–5.21]; p=0.001). Conclusion Patients over 70 years old with drug-refractory symptomatic AF presented with higher epicardial fat volume. Epicardial fat burden showed similar predictive power for AF relapse after PVI in this subset of patients, representing a useful tool for intervention decision across this age spectrum. Funding Acknowledgement Type of funding source: None

Epicardial fat volume outperforms classic clinical scores for predicting atrial fibrillation relapse after pulmonary vein isolation

Abstract Background Epicardial adipose tissue has been implicated in the pathophysiology of atrial fibrillation (AF), but its relevance to clinical practice remains uncertain. The aim of this study was to compare the performance of the amount of epicardial fat with previously published clinical scores of AF-relapse risk after pulmonary vein isolation (PVI). Methods We assessed 575 patients (354 men, age 61±11 years, 449 paroxysmal AF) with symptomatic AF undergoing cardiac CT prior to a PVI procedure. Epicardial fat was quantified on contrast-enhanced images using a new simplified semi-automated method. The study endpoint was symptomatic and/or documented AF recurrence at 12 months. Epicardial fat was compared against the following scores: MB-LATER, APPLE, DR-FLASH, and ATLAS. Results Median follow-up was of 22 months (IQR 12–35), 232 patients relapsed, 130 patients (27%) within the first 12 months. After adjustment for BMI and other univariate predictors of relapse, three variables emerged independently associated with time to AF recurrence: non-paroxysmal AF (HR 2.03, 95% CI: 1.53–2.69, p&amp;lt;0.001), indexed left atrial (LA) volume (HR 1.02 per mL/m2, 95% CI: 1.01–1.02, p&amp;lt;0.001), and indexed pericardial fat volume (HR 1.55 per mL/m2, 95% CI: 1.43–1.67, p&amp;lt;0.001). Based on the ROC curve analysis, the epicardial fat showed greater discriminative power, with a C-statistic of 0.76 (95% CI: 0.71–0.81) against 0.67 (p=0.007 for pairwise comparison of ROC curves), 0.67 (p=0.01), 0.63 (p&amp;lt;0.001) and 0.57 (p&amp;lt;0.001) for the MBLATER, APPLE, DR-FLASH and ATLAS scores, respectively. The C-statistic for indexed LA volume and non-paroxysmal AF AUC were of 0.63 (p&amp;lt;0.001) and 0.61 (p&amp;lt;0.001), respectively. Conclusion Pericardial fat volume is a strong independent predictor of AF relapse after PVI, outperforming clinical scores of post-PVI AF. The underlying mechanisms of this association deserve further study. ROC Curve Analysys Funding Acknowledgement Type of funding source: None

Efficacy of Combined Cox-Maze IV and Ventricular Septal Myectomy for Treatment of Atrial Fibrillation in Patients With Obstructive Hypertrophic Cardiomyopathy

Atrial fibrillation (AF) has important clinical consequences in hypertrophic cardiomyopathy (HC). Safety and efficacy of the Cox-Maze IV procedure (when combined with ventricular septal myectomy) in patients with obstructive HC and paroxysmal AF is largely unresolved. Records of 395 consecutive HC patients (age 55±13 years) who underwent septal myectomy for heart failure symptoms between 2004 and 2015 were reviewed. Sixty-two patients also had concomitant complete biatrial Cox-Maze IV for a history of symptomatic paroxysmal AF (3.0±3.6 episodes) combined with myectomy comprise the study cohort. Freedom from symptomatic AF recurrences after operation was assessed. Left ventricular outflow gradients were reduced from 81 ± 28 mm Hg preoperatively to 1.2 ± 6.8 mm Hg after operation. At most recent follow-up, 53 patients (85%) were asymptomatic or mildly symptomatic. Freedom from recurrent symptomatic AF after myectomy/Cox-Maze IV was: 85% (95% confidence interval [CI] 73, 92) at 1 year, 69% (95% CI 55, 79) at 3 years, and 64% (95% CI 48, 75) at 5 years, including 34 patients (54%) who have experienced no symptomatic AF episodes for up to 8.2 years following surgery. The only clinical predictor of recurrent AF over follow-up was preoperative transverse left atrial dimension ≥45mm (p <0.01). In conclusion, biatrial Cox-Maze IV combined with septal myectomy is associated with favorable long-term freedom from symptomatic paroxysmal AF recurrence, as well as from obstructive heart failure symptoms. These data support myectomy/Cox-Maze as an effective management option for the subgroup of HC patients with symptomatic outflow obstruction and paroxysmal AF.