Mean Duration Of Atrial Fibrillation Research Articles

Predictive value of guideline-referred risk scores in estimating left atrial low voltage areas and recurrence of atrial fibrillation in repeat ablation procedures

Abstract Background Despite advances in mapping and ablation techniques, atrial fibrillation (AF) recurrence remains a challenge after pulmonary vein isolation. Low voltage areas (LVA) in the left atrium are associated with higher recurrence rates after left atrial ablation. Risk scores for evaluating post-ablation recurrences are not well established, although a better patient selection for repeat procedures would be of great help in clinical practice. Purpose Risk scores for prediction of AF recurrence have not been tested in a cohort of repeat ablations. Methods This single-center study includes consecutive patients from the prospective Bernau ablation registry undergoing ultra-high-density (UHD) mapping and repeat ablation for AF/AT recurrence between 2016 and 2020. The potential of seven guideline mentioned risk scores (APPLE, DR-FLASH, MB-LATER, ATLAS, CAAP-AF, BASE-AF 2, ALARMEc) to predict (1) AF/AT recurrence beyond a three-months blanking period after repeat left atrial ablation (Re-PVI ± further LA ablation) and (2) the percentage of left atrial LVA in UHD mapping was investigated. LVA were defined as sites with a bipolar peak-to-peak voltage of <0.5 mV with an extent of >1cm². Optimal cutoff for sensitivity and specificity for LVA and AF/AT recurrence as endpoint was chosen using C statistics with receiver-operator characteristics (ROC). Further ROCs were performed to illustrate the predictive ability of the scores. Pearson correlation was used to test associations between variables. Results 160 patients (mean age 67.9 ± 9.1 years, 60.6% persistent AF, mean AF duration 4.6 ± 3.8 years) with complete left atrial UHD mappings (mean EGMs 9754 ± 5808) were included. Overall recurrence rate over a mean follow-up time of 16 ± 11 months was 55.6%. The predictive value of the investigated risk scores on AF/AT recurrence in our cohort was low (Table 1), with the highest power for CAAP-AF (p = 0.015, AUC = 0.615) and DR-FLASH score (p = 0.040, AUC = 0.594), Figure 1. With respect to left atrial LVA we found a better predictive power for the CAAP-AF (p < 0.001, AUC 0.702), APPLE (p < 0.001, AUC 0.687), DR-FLASH (p < 0.001, AUC 0.688), ATLAS (p = 0.005, AUC 0.634) and ALARMEc (p = 0.007, AUC 0.608) score to predict low voltage based on a calculated cut-off of 22% of total left atrial surface (Figure 1). Conclusion The predictive value of guideline-referred risk scores in estimating AF/AT recurrence after repeat ablation is low and does not seem to be of relevant help in patient selection for further interventional treatment. Some scores demonstrate a fairly good prediction for the amount of left atrial LVA and therefore might help in choosing the right mapping and ablation regime beforehand.

Spontaneous atrial fibrillation occurrence following transesophageal atrial burst pacing in rats

Abstract Purpose Animal models play a crucial role in elucidating the complex pathophysiology of atrial fibrillation (AF) and in identifying and testing novel antiarrhythmic strategies. We aimed to develop and characterize a new experimental rat model of AF, induced by long-term transesophageal atrial electrical stimulation, and to investigate whether the "AF begets AF" concept applies to small rodent hearts. Method Twelve adult male Wistar rats were randomized into two groups: Sham (n = 5) and AF (n = 7). All rats were implanted at the beginning of the study with ECG radiotelemetry devices and underwent continuous ECG monitoring throughout the study. To induce AF, the rats in the AF group underwent atrial pacing for 10 consecutive days (15 successive cycles of stimulation/day, 20 s each, with a free interval of 5 min between cycles; 4,000 stimuli/min, stimulus duration 6 ms, voltage 3 V above the diastolic threshold). A similar procedure was applied to the Sham group, but without performing the actual electrical stimulation. The number and duration of spontaneous AF episodes were evaluated based on continuous ECG monitoring prior to, during, and for one week after transesophageal atrial pacing. The inducibility of AF and the occurrence and duration of spontaneous AF episodes were evaluated and compared between the two groups. Results Atrial fibrillation was induced in 85.7% of the rats subjected to atrial electrical pacing (Figure, A), with an average global inducibility of 44.0% ± 16.9% and a mean AF duration of 123.2 ± 96.3 s. No induced or spontaneous AF episodes were recorded in any of the Sham animals. In the AF group, none of the animals presented spontaneous AF before transesophageal atrial pacing. However, in the AF rats, after atrial electrical stimulation initiation, the number of atrial premature beats significantly increased (21.3 ± 6.8 / 24-h post-stimulation vs. 7.3 ± 6.5 / 24-h at baseline; p< 0.01; Figure, B), and all rats presented spontaneous AF episodes (Figure, C). At the end of the study, AF rats presented a total number of 23.9 ± 2.3 AF episodes / 24-h (Figure, D), with a mean AF burden of 337.7 ± 25.06 s / 24-h. Conclusions Our data demonstrate that, despite the small size of the atria, the "AF begets AF" concept is applicable in small rodents. The study presents a novel rat model of AF, in which spontaneous AF occurs following long-term atrial electrical stimulation. Given that the model is relatively rapid and easy to implement, it provides a setup for further investigation of AF pathophysiology, and for identifying and testing novel therapeutic strategies for AF.Figure 1

First clinical data on artificial intelligence-guided catheter ablation in long-standing persistent atrial fibrillation.

Despite advanced ablation strategies and major technological improvements, treatment of persistent atrial fibrillation (AF) remains challenging and the underlying pathophysiology is not fully understood. This study analyzed the multiple procedure outcome and safety of catheter ablation of spatiotemporal dispersions (DISPERS) detected by artificial intelligence (AI)-guided software in patients with long-standing persistent AF. The Volta VX1 software was used for 50 consecutive patients undergoing catheter ablation for persistent AF. First, high-density mapping (78% biatrial) with a multipolar mapping catheter was performed. In addition to pulmonary vein isolation (PVI), ablation of DISPERS was performed aiming at homogenizing, dissecting, isolating, or connecting DISPERS areas to nonconducting anatomical structures. Follow-up contained regular visits at our outpatient clinic at 1, 3, 6, and 12 months including 7-day Holter electrocardiograms. Patients were mainly suffering from long-standing persistent AF (mean AF duration 50.30 ± 54.28 months). Following PVI, ablation of left atrial and right atrial DISPERS areas led to AF cycle length prolongation (mean of 162.0 ± 16.6to 202.2 ± 21.6 ms after) and AF termination to atrial tachycardia (AT) or sinus rhythm (SR) in 12 patients (24%). No stroke or pericardial effusion occurred; major groin complications (pseudoaneurysm n = 1, atrioventricularfistula n = 1) were detected in two patients. After a blanking period of 6 weeks, recurrence of any atrial arrhythmia was documented in 26 patients (52%). The majority of patients presented with organized AT (n = 15) while AF was present in n = 9 patients and AT/AF was observed in n = 2 patients. Twenty-twopatients underwent reablation. During a mean follow-up of 363.14 ± 187.42 days and after an average of 1.46 ± 0.68 procedures, 82% of patients remained in stable SR. DISPERS-guided ablation using machine learning software (the Volta VX1 software) in addition to PVI in long-standing persistent AF ablation resulted in high long-term success rates regarding AF and AT elimination. Most arrhythmia recurrences were reentrant AT. After a total of 1.46 ± 0.68 procedures, freedom from AF/AT was 82%. Despite prolonged procedure times complication rates were low. Randomized studies are necessary to evaluate long-term efficacy of dispersion-guided ablation using AI.

A comparison between stand-alone left atrial appendage occlusion and resection as a method of preventing cardiogenic thromboembolic stroke.

The present study evaluated the differences between left atrial appendage occlusion (LAAO) and left atrial appendage resection (LAAR) in terms of the safety and efficacy. From January 2018 to August 2022, 94 patients underwent a stand-alone LAAO, and 90 patients underwent stand-alone LAAR in our institution. All of these patients were included in this study. LAAO was performed via left mini-thoracotomy, and LAAR was performed via a left thoracoscopic approach. The patients' characteristics and perioperative and postoperative data were obtained by retrospectively reviewing their medical records. The mean age of the patients was 72.4 ± 10.2 (LAAO) and 66.2 ± 9.4 (LAAR) years old (P < 0.05). There were no marked differences in the mean duration of atrial fibrillation (AF) or the ratio of AF type between both groups. The average CHA2DS2-Vasc scores were 4.4 ± 1.6 (LAAO) and 2.7 ± 1.8 (LAAR) (P < 0.05), and the average HAS-BLED scores were 2.9 ± 1.0 (LAAO) and 2.2 ± 1.2 (LAAR) (P < 0.05). The mean operation time was 49 ± 20min (LAAO) and 34 ± 15min (LAAR) (P < 0.05). No substantial gaps were detected in preoperative echo-graphic findings between the groups. No significant differences were observed in the amount of intraoperative or postoperative bleeding or the rate of intraoperative massive bleeding events between the groups. Successful LAA closure was achieved in all cases in both groups. Approximately 50% of patients underwent concomitant left pulmonary vein isolation (LPVI) during surgery, indicating no significant differences between the groups (P = 0.872). The early mortality rate was 1.04% in the LAAO group and 0% in the LAAR group (P = 0.132). There was no significant difference in the rate of postoperative LAA stump thrombus between the groups (8.5% in the LAAO group and 6.7% in the LAAR group; P = 0.320). The mean follow-up period was 851 ± 500 (6-1618) days in the LAAO group and 1208 ± 357 (49-1694) days in the LAAR group. Postoperative stroke events were detected in 1 patient in each group (P = 0.432). There was no significant difference in the sinus rhythm recovery rate after LPVI between these groups (31.1% in the LAAO group and 28.6% in the LAAR group; P = 0.763). There were no significant differences between LAAO and LAAR in terms of the feasibility and the effectiveness as a method for stroke prophylaxis only to selected patients for both procedures, although further studies including the comparison between groups with the same backgrounds to confirm the authentic differences in the clinical results between these procedures.

Albumin as a Prognostic Marker for Atrial Fibrillation Recurrence following Cryoballoon Ablation of Pulmonary Venous.

Introduction: Atrial fibrillation (AF) recurrence following pulmonary vein isolation (PVI) ablation has clinical significance. Identifying risk factors for AF recurrence is important. We investigated serum albumin (SA) levels (g/dL) as a prognostic factor for the recurrence of AF following cryoballoon PVI ablation. Methods: We included patients who underwent cryoballoon PVI ablation at our institution between the years 2013 and 2018. The primary outcome was recurrence of AF during follow up. Results: Our cohort consisted of 126 patients (67% males, mean age 61.8 ± 10.0 years). The pattern of AF amongst the cohort was paroxysmal in 62.5%, persistent in 25.4%, and longstanding persistent in 6.3%. Those with lower SA levels had a mean AF duration significantly less than those with higher SA levels (2.81 years, 7.34 years, and 6.37 years for SA levels of <3.8, 3.8−4.1, and ≥4.1, respectively; p = 0.003). Patients with lower SA levels were significantly more likely to have had more previous cardioversions and a larger left atrial area and volume. The mean follow-up was 380 days, in which the AF recurrence rate was 20.6%. Patients with lower SA level had significantly more AF recurrences (47.4%, 16.7%, and 2.2% for SA levels of <3.8, 3.8−4.1, and ≥4.1, respectively; p < 0.001). Upon multivariate analysis, an SA level < 3.8 was associated with a higher risk of AF recurrence (OR = 5.422 95% CI 1.134; 25.910; p < 0.001). Conclusion: SA levels were found to be a strong independent marker for AF recurrence following PVI ablation.

Abstract 14899: Ten Year Performance of Convergent Cryoballoon Hybrid Ablation With Left Atrial Appendage Exclusion in Persistent and Long Standing Persistent Atrial Fibrillation: A Trac-Af Registry Outcome Study

Introduction: Catheter ablation (CA) efficacy in persistent and long standing persistent atrial fibrillation (AF) remains poor. The Convergent procedure with endocardial cryoballoon and left atrial appendage exclusion (LAAE) addresses multiple epicardial/endocardial targets offering a comprehensive approach. We report clinical outcomes in a prospectively collected registry supplemented by continuous device monitoring in a diseased AF patient population. Methods: Single center patient data were retrospectively analyzed in the TRAC-AF registry (NCT05111015) between November 2011-November 2021. Epicardial ablations were performed by cardiothoracic surgeon and endocardial CA performed by electrophysiologist. Clinical follow up was performed at 3, 6, and 12 months and every 6 months thereafter. AF burden was determined from patients with ≥30 days of 24 hr continuous rhythm monitoring following a 90 day blanking period. Results: A total of 228 patients (69% male) received hybrid Convergent ablation. Mean age was 66 yrs, mean BMI was 30.2 ± 6.2, and in 70% of patients, CHA2DS2-VASc was ≥2. Baseline AF types were paroxysmal (7%), persistent (43%), and longstanding persistent (50%). Mean AF duration was 5.1 ± 6.2 yrs. Fifty-seven percent of patients had failed CA prior to hybrid ablation and 30.6% had LAAE with an epicardial clip. Of 228 patients, 114 (50%) had continuous rhythm monitoring. Mean residual AF burden was 5.2 ± 16.3% and of those, 77% had ≤1% mean residual AF burden, and 88% had ≤5% mean residual AF burden. A repeat CA after hybrid Convergent occurred in 23% (53/228) of patients at a mean 645.8 ± 511.4 days from the index procedure with 4.4% requiring &gt;1; 88.5% of all repeat ablations included a mitral annular line. Conclusions: The hybrid Convergent ablation with endocardial cryoballoon and LAAE provides long term sustainable low AF burden despite rigorous endpoint surveillance in a significantly diseased AF population which includes prior failed CA patients over a decade of follow up.

Sex differences in presentation of atrial fibrillation: Findings from 30-day ambulatory monitoring in real-world practice

BackgroundWomen are less likely to receive oral anticoagulation or ablation for treatment of atrial fibrillation (AF). Identification of sex differences in arrhythmia characteristics and symptoms may lead to a better understanding of potential reasons for these differences. ObjectivesTo determine sex differences in AF with respect to heart rate, duration, burden, and symptoms in patients undergoing mobile cardiac telemetry (MCT) monitoring. MethodsAll patients who registered for ≤30-day MCT using PocketECG (MediLynx) in the USA in 2017 were included (n = 27,512, 58 % women). PocketECG records and transmits a three-lead ambulatory electrocardiogram (ECG) with real-time beat-to-beat analysis. Sex-related differences were analyzed with Chi2 and Spearmans rho. ResultsFewer women than men were diagnosed with AF lasting ≥30s (13.7 % versus [vs] 19.0 %, p < 0.001). AF burden was lower in women in all age groups <90 years (all p < 0.01). Women were older at the time of AF diagnosis (median 76 vs 73 years, p < 0.001), had faster heart rate during AF (mean: 104.7 ± 26.0 vs 96.7 ± 26.7 bpm, p < 0.001), and shorter AF duration (mean: 96.2 ± 176.0 vs 121.6 ± 189.9 min, p < 0.001). There was a non-significant trend toward more symptoms (such as dizziness, racing heart, fatigue, or palpitations) during AF in women compared to men (46.5 % vs 43.7 %, p = 0.062). ConclusionsAF was less prevalent and occurred at lower burdens in women than men in each age strata. Despite faster heart rates in AF in women, there were no significant sex differences in reported symptoms during AF. Sex differences in therapy cannot be explained by differences in symptoms or rates in AF. Condensed abstractReal-world data on sex differences in AF using a 30-day MCT monitoring device remain scarce. We aim to determine the sex differences in AF with respect to prevalence, burden, heart rate, and symptom in patients undergoing ≤30-day MCT monitoring. Our data analysis suggests that fewer women than men had AF, women were older at diagnosis of AF, and women with AF had higher mean heart rate, shorter mean AF duration, and lower mean AF burden than men. Further studies are needed to examine reasons for sex differences, specifically in relation to AF therapy and its impact on clinical outcomes.

Evaluation of atrial contractility and remodeling after the Maze-3 procedure with combined heart interventions

Highlights. The most important goal of atrial fibrillation surgical treatment is to eliminate the arrhythmia in order to restore atrial contractility and improve their transport function. Our study showed positive dynamics of atrial contractility and remodeling after the maze-3 procedure against the background of a regular heart rhythm restoration. The study of sinus rhythm predictors maintenance and recovery of atrial transport function will help to make patient selection more personified.Aim. Evaluation of atrial contractility and remodeling after the maze-3 procedure with combined interventions on the heart.Methods. The analysis of 217 combined surgical interventions was carried out, where a maze-3 was used to treat atrial fibrillation (AF). The operations were performed in our center from 2012 to 2016. Key points of the study: rhythm after surgery and echocardiographic control in the long-term follow-up in order to determine the dynamics of atrial contractility and volumes. The average follow-up period was 47 (1–100) months. 40 (18.4%) patients had paroxysmal, 38 (17.5%) persistent, 139 (64.1%) long-term persistent AF. The mean AF duration before surgery was 27.4 months (1–200 months). The indications for the maze-3 procedure were: ineffectiveness of antiarrhythmic therapy, the need to perform combined cardiac procedures. We used standard statistical research methods with one – and multivariate logistic regression.Results. In the long-term follow-up, sinus rhythm (SR) persists in 79% of patients. In the long-term follow-up, in this group of patients, the left atrial contractility was restored from 76% to 91%, while the biatrial contractility increased from 82 to 96%. Shorter AF duration before surgery was a positive predictor of SR recovery and atrial contractility (p = 0.005), while pulmonary artery pressure and patient age negatively affected these indicators (p = 0.041 and p = 0.038, respectively). The presence of SR early after surgery was not a significant predictor of AF freedom. At the same time, according to the long-term observations, patients maintaining a regular atrial heart rate had positive indicators of atrial systolic function restoration and a positive dynamics of a decrease in atrial volumes.Conclusion. SR and restoration of left atrial contractility are two interrelated goals of the maze procedure. The negative factors associated with the failure of surgical treatment of AF are increased pressure in the pulmonary artery, long-term AF before surgery, and the age of patients.

Mitral valve surgery for atrial functional mitral regurgitation: predicting recurrent mitral regurgitation and mid-term outcome

ObjectivesThis study aimed to elucidate the mid-term outcomes and risk factors for recurrent mitral regurgitation after mitral valve (MV) surgery for atrial functional mitral regurgitation (AFMR).Methods and resultsWe retrospectively analyzed data of 50 consecutive patients (median age 74 years; 29 men) who underwent mitral valve surgery for AFMR between January 2001 and January 2019. Mean atrial fibrillation duration was 12 years. During the follow-up period of 4.6 ± 4.4 years, 5 cardiac-related deaths were identified. Five- and 10-year freedom from cardiac-related death rate for all patients was 88.4% and 78.6%. In total, 42 patients underwent MV repair with mitral annuloplasty and 8 underwent MV replacement. Five- and 10-year freedom from cardiac-related death rate in patients who underwent MV repair was 93.1% and 82.7%, which was better than MV replacement (log rank p = 0.04). During the follow-up period, MR recurrence rate was 16.8% at 5 and 10 years for the patients who underwent MV repair. Univariate analysis showed that partial band annuloplasty and preoperative elevated left ventricular end-systolic volume index were risk factors for recurrent MR after MV repair. Multivariate analysis identified partial band annuloplasty as the independent predictor for recurrent MR during long-term follow-up after MV repair for AFMR.ConclusionPatients who underwent MV repair for AFMR could have an acceptable mid-term outcome. However, MVR might not improve the mid-term outcome in patients with AFMR. The use of partial bands for mitral annuloplasty would not be recommended in terms of recurrent MR mid-term.

Coronary Angiographyic Findings in Patients of Acute Coronary Syndrome with Atrial Fibrillation

Background: Acute coronary syndrome (ACS) is a fatal entity and can be even more deadly if they develops concomitant complications in the form of arrhythmias like atrial fibrillation. Coronary artery disease is thought to be more severe in cases with ACS and atrial fibrillation. Objective: To determine the angiographic findings in patients presenting with acute coronary syndrome and atrial fibrillation and To find the involvement of more common circulation (right or left coronary circulation) leading to atrial fibrillation in acute coronary syndrome. Materials and Methods: This 6 month case series study conducted at department of Cardiology, Sheikh Zayed Hospital, Rahim Yar Khan from14-01-20 to 14-09-20. A total of 198 cases aged 30-60 years of both gender were included in the study through non-probability consecutive sampling. Patients suffering with ACS and has atrial fibrillation on presentation or develops within 24 hours of admission were included. They underwent coronary angiography to look for number of vessels involved, severity of coronary artery disease and culprit vessel involved. Results: In this study there were total 198 cases. Mean age of the participants was 50.09±5.88 years and mean duration of atrial fibrillation was 14.91± 4.51 hours. There were 70 (35.35%) cases with DM, 78 (39.39%) with HTN and 61 (30.81%) smokers. STEMI was found in 35 (17.68%) and NSTEMI in 152 (76.77%) of cases as in figure 05. One vessel disease was observed in 26 (13.13%), two vessel disease in 147 (74.24%) and three vessel disease in 25 (12.63%) of cases. Mild disease on angiography was seen in 45 (22.73%), moderate in 132 (66.67%) and severe in 21 (10.61%) of the cases.it was found that out of 198 patients , 146 ( 74 %) had right coronary artery culprit lesion and 51 ( 26 %) has left sided coronary circulation culprit lesion and from left coronary circulation, left circumflex was most commonly involved : 41 ( 21 % ) of patients as compared to only 10 ( 5 %) patients had culprit in left anterior descending artery. Conclusion: AF in patients with ACS is most commonly associated with right coronary artery lesionsand right type of coronary circulation. In terms of number and severity of disease the most common pattern observed was two vessel disease comprising almost 3/4th of all cases and moderate disease was in most of the vesselsrespectively. Key words: ACS, Atrial fibrillation

Frequency of Achieving Target INR in Patient on Warfarin for Atrial Fibrillation

Background: Warfarin has long been established as the oral anticoagulant of choice. The benefits of warfarin depend on maintaining the International Normalized Ratio (INR). It has been shown that the optimal INR target range is 2-3 for AF patients. Very less number of patients had been reported to achieve and remain in that target INR range. The prevalence of AF in the general population is about 1.6% in women and 2.4% in men and is generally lower in Asian countries Aim: To determine the frequency of achieving target INR in patient on warfarin for atrial fibrillation. Methodology: This is cross sectional study conducted at national institute of cardio vascular disease, Karachi from 31st May 2016 30th November 2016.The sample size of the study were 111, and nonprobability convenience sampling technique was used. Results: Among study population 61 (54.9%) were male and 50(45%) female patients. Mean duration of atrial fibrillation was 3.44±0.97 years. The mean duration of warfarin taken was 11.34±3.96 months. INR (2-3) target achieved in 72(64.9%) patients. Significant association of achieved INR target was observed with duration of atrial fibrillation, duration of warfarin, hypertension, stroke, and Left ventricular dysfunction. Conclusion: Target of INR was achieved in 64.9% patients when these patients were given warfarin doses of 5.0 to 7.5 mg/day. Keywords: Achieving Target INR, Warfarin, Atrial Fibrillation.

SIMULTANEOUS HYBRID ABLATION WITH EPI-ENDOCARDIAL MAPPING FOR THE TREATMENT OF LONG STANDING PERSISTENT ATRIAL FIBRILLATION

BACKGROUND While the paroxysmal form of atrial fibrillation (AF) can be managed pharmaceutically with antiarrhythmic drugs or by means of catheter ablation, persistent AF and longstanding persistent atrial fibrillation (LsP-AF) have presented more of a challenge. Hybrid ablation offers a minimally invasive tailored approach for these non-paroxysmal forms of AF which are associated with a more complex substrate. Moreover, given the recent evidence of endo-epicardial electrical asynchrony that can develop in patients with PAF and LsP-AF it is necessary to extensively validate lesion transmurality. Our hybrid technique employs high-density electrical mapping of both the epicardial and endocardial surfaces allowing the team to validate endpoints of ablation in an extensive manner during the procedure which mitigates the risk of incomplete ablation lines that could create re-entrant circuits and recurrence of AF (Fig.1 A-D). METHODS AND RESULTS We describe the outcomes of 15 consecutive patients who underwent simultaneous thoracoscopic hybrid ablation with epi-endocardial mapping for the treatment of LsPAF (Fig.1 E-H). Patient outcomes were recorded at 3 months, 6 months, 1 year and last follow-up greater than 1 year for each patient. Rhythm status was obtained primarily via a 24 hr Holter monitor and if that was not available, ECG measurements were used. Table 1 lists patient and procedure characteristics: age 62.7±11 yr; mean AF duration 51.6 months [range: 14-130]; previous transcatheter (TC) ablation 3/15 (20%); previous cardioversion 12/15 (80%); box lesion set 15/15 (100%); ablation time 20 ±4 mins; surgical gaps 8/15 (53%); adverse events (bleeding/stroke/pacemaker implantation) (0%). At discharge 13/15 (86.6%) of patients were in sinus rhythm (SR) with a mean post-op stay of 3.8 ± 1.1 days. SR restoration was as follows: 3 month 14/15(93.3%), 6 month 13/15 (86.7%) SR off anti-arrhythmic drugs (AAD), 1yr 11/15 (73.3%) SR off AAD. At last follow-up (22±7 month) 13/15 (86.7%) patients were in SR with 11/15 (73.3%) patients in SR off AAD; 4 patients underwent repeat TC ablation 18±3.6 month post hybrid ablation. The same areas that were endocardially targeted as surgical gaps during the index procedure were re-ablated (3/4) and areas that were not seen as surgical gaps in the first place were ablated during the repeat TC procedure (4/4). CONCLUSION Our hybrid approach is safe, feasible and has shown successful SR restoration off AAD in 73% (11/15) of our patients at 1 year follow-up and epicardial mapping before and after endocardial ablation provided an additional means of lesion validation. While the paroxysmal form of atrial fibrillation (AF) can be managed pharmaceutically with antiarrhythmic drugs or by means of catheter ablation, persistent AF and longstanding persistent atrial fibrillation (LsP-AF) have presented more of a challenge. Hybrid ablation offers a minimally invasive tailored approach for these non-paroxysmal forms of AF which are associated with a more complex substrate. Moreover, given the recent evidence of endo-epicardial electrical asynchrony that can develop in patients with PAF and LsP-AF it is necessary to extensively validate lesion transmurality. Our hybrid technique employs high-density electrical mapping of both the epicardial and endocardial surfaces allowing the team to validate endpoints of ablation in an extensive manner during the procedure which mitigates the risk of incomplete ablation lines that could create re-entrant circuits and recurrence of AF (Fig.1 A-D). We describe the outcomes of 15 consecutive patients who underwent simultaneous thoracoscopic hybrid ablation with epi-endocardial mapping for the treatment of LsPAF (Fig.1 E-H). Patient outcomes were recorded at 3 months, 6 months, 1 year and last follow-up greater than 1 year for each patient. Rhythm status was obtained primarily via a 24 hr Holter monitor and if that was not available, ECG measurements were used. Table 1 lists patient and procedure characteristics: age 62.7±11 yr; mean AF duration 51.6 months [range: 14-130]; previous transcatheter (TC) ablation 3/15 (20%); previous cardioversion 12/15 (80%); box lesion set 15/15 (100%); ablation time 20 ±4 mins; surgical gaps 8/15 (53%); adverse events (bleeding/stroke/pacemaker implantation) (0%). At discharge 13/15 (86.6%) of patients were in sinus rhythm (SR) with a mean post-op stay of 3.8 ± 1.1 days. SR restoration was as follows: 3 month 14/15(93.3%), 6 month 13/15 (86.7%) SR off anti-arrhythmic drugs (AAD), 1yr 11/15 (73.3%) SR off AAD. At last follow-up (22±7 month) 13/15 (86.7%) patients were in SR with 11/15 (73.3%) patients in SR off AAD; 4 patients underwent repeat TC ablation 18±3.6 month post hybrid ablation. The same areas that were endocardially targeted as surgical gaps during the index procedure were re-ablated (3/4) and areas that were not seen as surgical gaps in the first place were ablated during the repeat TC procedure (4/4). Our hybrid approach is safe, feasible and has shown successful SR restoration off AAD in 73% (11/15) of our patients at 1 year follow-up and epicardial mapping before and after endocardial ablation provided an additional means of lesion validation.

Achieving acute mitral isthmus block with catheter ablation with vein of marshall ethanol infusion

Abstract Funding Acknowledgements Type of funding sources: None. Background Achieving bidirectional mitral isthmus block during radiofrequency (RF) ablation for persistent atrial fibrillation (AF) is still challenging. The conventional ablation method involves RF applications on the endocardial aspect of the Mitral Isthmus (MI), and for a majority of patients, in the distal coronary sinus (CS). Purpose We have evaluated the acute success of obtaining mitral isthmus block by adding another epicardial component using ethanol infusion in the vein of Marshall (EIVOM) in addition to endocardial MI and epicardial CS ablation. Methods We studied 121 patients (pts.) with a mean age of 65 years (range 40-83) 73% men; 119 with longstanding persistent AF (98%) and 2 with perimitral flutter (2%). The mean duration of AF was 53 months (12-244 months). In the majority of patients, additional endocardial (on the ventricular aspect of the MI) and/or epicardial (distal CS) (RF) ablation was performed in order to achieve MIB. The ablation procedure was performed under general anesthesia (GA) for 81 pts (67%). EIVOM was perform with a mean 6 ml ethanol (range 2-10ml) Results Bidirectional MIB was obtained in 114 pts. (94,2%). The 7 patients without MIB were scheduled for another ablation procedure (4 pts under GA during the first procedure). The average RF delivery time to block was 160 seconds (range 42-480 seconds) for the endocardial MI RF ablation (point-by-point application with a power of 50W and an Ablation Index of 450-500, contact force 10-20g) and 156 seconds (range 55-438) for the epicardial MI RF ablation (applications with a power of 20W). Bidirectional endocardial and epicardial MIB was confirmed by conventional pacing maneuvers performed in sinus rhythm. No major complications were observed. The parameters associated with failure for MIB were AF duration, Left Atrial dilatation &amp;gt;200 ml, MI thickness (epicardial endocardial distance on the CARTO maps &amp;gt;15mm). Conclusion Ethanol infusion in the vein of Marshall is a safe approach and is associated with a higher success rate of obtaining acute bidirectional endocardial and epicardial mitral isthmus block when compared with the conventional method. Abstract Figure. Bloc Mitral Endo; Bloc Mitral Epi;

Sinus rhythm heart rate increase after atrial fibrillation ablation is associated with lower risk of arrhythmia recurrence.

Pulmonary vein isolation (PVI) with autonomic modulation may be more successful than PVI alone for atrial fibrillation (AF) ablation and may be signaled by changes in sinus rhythm heart rate (HR) post ablation. We sought to determine if a change in sinus rhythm HR predicted AF recurrence post PVI. Patients who underwent AF ablation from 2000 to 2011 were included if sinus rhythm was noted on ECG within 90 days pre and 7 days post ablation. Basic ECG interval and HR changes were analyzed and outcomes determined. A total of 1152 patients were identified (74.3% male, mean age 57 ± 11 years). Mean AF duration was 5.2 ± 5.3 years. Paroxysmal AF was noted in 712 (61.8%) of the patients. Mean EF was 61% ± 6%. Sinus rhythm HR was 61 ± 11 pre-ablation and 76 ± 13bpm post-ablation (27% ± 24% increase, p<.001). The ability of relative HR change post-ablation to predict AF recurrence was borderline (hazard ratio 0.65 [0.41-1.01], p=.067). With patients separated into quartiles based on the relative HR change, the upper quartile with the largest relative increase in HR had a significantly lower rate of AF recurrence compared to the lowest quartile following multi variable modeling (p=.038). There were significant changes in PR (171 ± 28 to 167 ± 30ms) and QTc (424 ± 25 to 434 ± 29ms) intervals (both p<.001) but these were not predictive of outcome. Relative changes in HR post AF ablation correlates with AF recurrence. Further prospective studies are needed to confirm this relationship.

Abstract 14616: Tailored Low Voltage Zones Ablation Using Contact Force Sensing Technology in Patients With Persistent Atrial Fibrillation (TWEET-AF): A Pilot Study

Introduction: Although pulmonary vein (PV) isolation (PVI) is very effective in paroxysmal atrial fibrillation (AF), in patients (pts) with persistent AF, PVI often is not sufficient. Many studies suggested that low voltage zones (LVZs) outside of the PV might be involved in the complex mechanisms perpetuating AF. However ablation strategies involving substrate modification (SM) did not show additional benefits in persistent AF pts. Those studies were performed before the introduction of contact force technology, and the most likely explanation for these results could be the inability to achieve effective transmural lesions and continuous linear ablation. Hypothesis: We hypothesized that the use of contact force technology would improve ablation efficacy. Therefore, we analyzed the long-term outcome after two different ablation strategies in pts with persistent AF depending on whether there was evidence of LVZs in the left atrium or not. Methods: The presence of LVZs were defined as sites of &gt;3 adjacent low-voltage points &lt;0.5 mV during electrophysiology study. Depending on the location of the LVZ, linear ablation was performed. Catheter ablation was performed using TactiCath™ or SmartTouch™ ablation catheters aiming at contact values ≥10g &lt;20g and FTI &gt;400g/s. Ablation was performed in a temperature-controlled fashion with energy of 30W except at the posterior wall (20-25W). Results: 121 consecutive pts with persistent AF (46 female, median age 66 [59-72] years, mean duration of AF 16 [7-73] months, CT derived LA volume index 66 [56-75]ml/m2) were included: pts without LVZs underwent PVI alone (n = 74), in pts with LVZs, PVI + SM (n = 47) was performed (mitral Isthmus line in 2, supero-septal line in 39, and roof line in 47; bidirectional block was achieved in 100%, 97%, and 100%, respectively). After a median follow-up of 13 [6-21] months, 86% of pts without and 78% with substrate were in sinus rhythm, mainly without antiarrhythmic drugs (89% PVI only, 84% PVI + SM). Conclusions: In patients with persistent AF without LVZs, PVI alone leads to excellent 2-year freedom from AF. In pts with LVZs, additional substrate modification with CF sensing technology is associated with improved success rates compared to previous studies.

Severe sleep apnea is associated with atrial fibrillation burden in pacemaker recipients

Abstract Background New generation pacemaker allow the assessment day by day of sleep disordered breathing (SDB) based on impedance measurement. A recent study demonstrated that incidence of AF is higher in case of severe SA monitored by pacemaker Purpose The aim was to compare the atrial fibrillation (AF) burden between patients with severe and non-severe sleep apnea (SA) detected with pacemakers monitoring (SDB). Methods This retrospective study was carried out at our University Hospital. We included all patients with Microport CRM pacemaker implanted from 2013 to 2016 at our university hospital. Exclusion criteria were inactivation of sleep apnea monitoring (SAM), history of sleep apnea, missing data or invalid data. AF burden was assessed according to Fallback mode switch (FMS) duration. Respiratory disturbance index (RDI) was calculated as the average number of events (ventilation pause and reductions) per number of hours of monitoring. Patients with RDI&amp;lt;20/h were compared with patients with RDI≥20/h (considered as severe SA group). Results 404 patients (mean age = 79.7±10 years; 52.0% men) were included. The most prevalent indication for cardiac pacing was atrioventricular block in 57%. Mean RDI was 18.9 events per hour. 234 (58%) of them had a mean RDI &amp;lt;20 and 170 (42%) had a mean RDI ≥20. Compared to patients with mean RDI&amp;lt;20, those with mean RDI ≥20 were youngers (78.6±10 years Vs 81.8±8 years; p=0.02), were more likely to be male (58.2% Vs 47.5%: p=0.035) and had more heart failure history (28.8% Vs 19.2%: p=0.03). BMI was not different between groups (26.3±5. vs 26.3±4; P=0.33). Mean follow-up was 27 months. Patients with RDI ≥20 had a mean Atrial fibrillation duration longer than patients with RDI &amp;lt;20 (631 min Vs 291 min respectively; p=0.014). RDI was correlated with FMS (r=0.26; p=0.0004). The stroke rate tended to be higher in the RDI ≥20 group (2.1% vs 5.4%) (p=0.12). Conclusion Severe SA detected by pacemaker was associated with longer AF duration. We did not find higher occurrence of stroke in the severe SA group. Funding Acknowledgement Type of funding source: None

Modulation of SERCA in Patients with Persistent Atrial Fibrillation Treated by Epicardial Thoracoscopic Ablation: The CAMAF Study.

Objectives: To evaluate atrial fibrillation (AF) recurrence and Sarcoplasmic Endoplasmic Reticulum Calcium ATPase (SERCA) levels in patients treated by epicardial thoracoscopic ablation for persistent AF. Background: Reduced levels of SERCA have been reported in the peripheral blood cells of patients with AF. We hypothesize that SERCA levels can predict the response to epicardial ablation. Methods: We designed a prospective, multicenter, observational study to recruit, from October 2014 to June 2016, patients with persistent AF receiving an epicardial thoracoscopic pulmonary vein isolation. Results: We enrolled 27 patients. Responders (n = 15) did not present AF recurrence after epicardial ablation at one-year follow-up; these patients displayed a marked remodeling of the left atrium, with a significant reduction of inflammatory cytokines, B type natriuretic peptide (BNP), and increased levels of SERCA compared to baseline and to nonresponders (p < 0.05). Furthermore, mean AF duration (Heart rate (HR) 1.235 (1.037–1.471), p < 0.05), Left atrium volume (LAV) (HR 1.755 (1.126–2.738), p < 0.05), BNP (HR 1.945 (1.895–1.999), p < 0.05), and SERCA (HR 1.763 (1.167–2.663), p < 0.05) were predictive of AF recurrence. Conclusions: Our data indicate for the first time that baseline values of SERCA in patients with persistent AF might be predictive of failure to epicardial ablative approach. Intriguingly, epicardial ablation was associated with increased levels of SERCA in responders. Therefore, SERCA might be an innovative therapeutic target to improve the response to epicardial ablative treatments.

P1741 Echocardiographic assessment of rate versus rhythm control strategy in patients with persistent atrial fibrillation

Abstract BACKGROUND Patients with persistent atrial fibrillation (AF) can be managed with either rhythm or rate control strategy. The restoration and maintenance of the sinus rhythm (SR) is not superior to the rate control regarding the total mortality and the rate of thromboembolic complications. Data concerning the effect of these strategies on left ventricular morphology and function is missing. PURPOSE The objective of our prospective randomised multicenter study in patients with persistent AF was to evaluate the effect of these two approaches on left ventricular morphology and function. METHODS The study group consisted of 205 patients (F/M 71/134; mean age 60.8 ± 11.2 years), including 101 patients randomized to the rate control approach (Group I) and 104 patients randomized to SR restoration with cardioversion and subsequent antiarrhythmic drug treatment (Group II). Mean duration of AF was 231.8 ± 112.4 days. At the end of follow-up (12 months), SR was present in 64% of patients in Group II. Echocardiographic examination was performed at a baseline and at 2 and 12 months. In the rate-control group, both right (22.1 ± 4.1 vs. 23.2 ± 3.8 cm2; p &amp;lt; 0.05) and left atrial (25.9 ± 5.2 vs. 26.8 ± 4.6 cm2 p &amp;lt; 0.05) enlargement was observed during the 12 months follow-up. A significant decrease in right (21.8 ± 3.0 vs. 21.2 ± 3.5 cm2; p &amp;lt; 0.05) and left atrial (26.2 ± 4.6 vs. 25.5 ± 5.0 cm2; p &amp;lt; 0.05) size in the rhythm control arm was observed. Both strategies led to a significant increase in left ventricular fractional shortening (32.1 ± 7.3 vs. 34.2 ± 6.5% and 31.3 ± 6.7 vs. 35.5 ± 8.9%, respectively; p &amp;lt; 0.05). The comparison of the left ventricular end-diastolic diameter revealed no difference within and between groups (50.8 ± 5.6 mm vs. 52.2 mm ± 6.8 mm at a baseline and 50.0 ± 6.0 vs. 52.0 ± ± 7.4 mm at 12 months, respectively). In rhythm-control group such trend was observed only in pts. with successfully maintained SR. According to LV function improvement, rhythm-control strategy was preferred in pts. with hypertension (RR 2.63; 95% C.I.: 0.93-5.45; p &amp;lt; 0.05) or congestive heart failure in NYHA II or III class (RR 2.13; 95% C.I.: 0.98-4.42; p &amp;lt; 0.05). CONCLUSIONS Both strategies led to a significant increase in LV FS. Rate-control strategy led to right and left atrium enlargement, but rhythm control resulted in their decrease.

Should concomitant surgical ablation for atrial fibrillation be performed in elderly patients?

ObjectiveThe incidence of atrial fibrillation increases with age, and therefore many elderly patients presenting for cardiac surgery have atrial fibrillation. In recent publications, increasing age has been recognized as a predictor for ablation failure. Furthermore, many surgeons are reluctant to perform a surgical ablation in elderly patients. We investigated the safety and efficacy of concomitant surgical atrial fibrillation ablation in elderly patients. MethodsBetween 2003 and 2013, 556 patients underwent concomitant surgical atrial fibrillation ablation at the University Heart Center Hamburg and served as our primary study cohort. During follow-up, rhythm monitoring was established by 24-hour Holter electrocardiogram (70.5%) or an implantable loop recorder (29.5%) at 3, 6, and 12 months postoperatively. The primary end point of the study was freedom from atrial fibrillation at 12 months follow-up and the detection of deviations from a linear association between age and risk of atrial fibrillation recurrence. A multiple logistic regression model including age as a linear term was used to identify predictors for rhythm outcome. ResultsMean patients’ age was 68.4 ± 9.07 years, and 67.3% of the patients were male. Mean duration of atrial fibrillation was 3.5 ± 3.3 years, and mean left atrium diameters were enlarged with 50.5 ± 8.8 mm. There were no major ablation-related complications. The 30-day and 1-year survivals were 97.7% and 95.8%, respectively. The overall rate of freedom from atrial fibrillation ranged from 62% to 72% and was independent of age. The age-dependent risk of atrial fibrillation at 12 months was significantly increased in elderly patients undergoing a concomitant coronary artery bypass grafting surgery. Multiple logistic regression model revealed double valve procedures (odds ratio, 3.48; P = .020), preoperative persistent atrial fibrillation (odds ratio, 2.43; P = .001), and coronary artery bypass grafting surgery in elderly patients (odds ratio, 2.03; P = .009) as risk factors for recurrence of atrial fibrillation. Sinus rhythm at discharge (odds ratio, 0.39; P < .001) and bipolar ablation (odds ratio, 0.32; P < .001) were significant predictors for successful ablation. ConclusionsSurgical atrial fibrillation ablation was safe and effective independently of age. Sinus rhythm at discharge and bipolar ablation were significant predictors for successful ablation, whereas double valve procedures, preoperative persistent atrial fibrillation, and coronary artery bypass grafting surgery in elderly patients were risk factors for recurrence of atrial fibrillation.

Risk Factors for Atrial Fibrillation Recurrence After Cox Maze IV Performed Without Pre-exclusion

New guidelines from The Society of Thoracic Surgeons recommend adding surgical ablation as a concomitant procedure for class I indications. We performed the maze procedure for all patients who experienced atrial fibrillation (AF) before cardiac surgery, without surgeon pre-exclusion. We retrospectively analyzed 83 patients, aged 71 ± 11 years (22% >80 years), who underwent Cox maze IV for persistent AF between 2014 and 2017. The mean AF duration (AFD) was 6.9 ± 8.6 years and European System for Cardiac Operative Risk Evaluation II was 7.2 ± 6.8. The 30-day mortality was 2.4%. During follow-up (mean, 675 days), the 1-, 2-, and 3-year survival rates were 92%, 86%, and 82%, respectively. No strokes were observed despite a mean CHA2DS2-VASC (Congestive heart failure, Hypertension, Age [≥65= 1 point, ≥75= 2 points], Diabetes, and Stroke/transient ischemic attack [2points], vascular disease, Sex [female = 1 point]) score of 4.1 (expected stroke rate, 4%/y). Twelve patients required a new pacemaker; 56of 73 survivors (77%) remained AF free. Multivariate logistic regression identified preoperative AFD, f wave size, and mean heart rate per Holter as important risk factors for AF recurrence, with AFD as the most important: 98% of patients with AFD less than 5 years remained AF free. Although the AF-free rate with the AFD of 5 or more years was only 55%, their symptoms improved without heart failure readmission. Concomitant atrial plication was performed more frequently in the group with AFD for 5 or more years, with greater atrial volume reduction and appreciable increases in stroke volume. The Cox maze IV procedure performed without pre-exclusion showed reasonable survival rates. Although AF recurred in patients with longer AFD, they fared well with substantial increases in stroke volume. Concomitant atrial volume reduction may have contributed to these additional benefits.