Paroxysmal After Atrial Fibrillation Research Articles

Association between left atrial low-voltage area and induction and recurrence of macroreentrant atrial tachycardia in pulmonary vein isolation for atrial fibrillation.

The relationship between induction and recurrence due to atrial tachycardia (AT) and left atrial (LA) matrix progression after atrial fibrillation (AF) ablation remains unclear. One hundred fifty-two consecutive patients with paroxysmal and persistent AF who underwent pulmonary vein isolation (PVI) and cavo-tricuspid isthmus (CTI) ablation and achieved sinus rhythm before the procedure were classified into three groups according to the AT pattern induced after the procedure: group N (non-induced), F (focal pattern), and M (macroreentrant pattern) in 3D mapping. The total rate of AT induction was 19.7% (30/152) in groups F (n = 13) and M (n = 17). Patients in group M were older than those in groups N and F, with higher CHADS2/CHA2DS2-VASc values, left atrial enlargement, and low-voltage area (LVA) size of LA. The receiver operating characteristic curve determined that the cut-off LVA for macroreentrant AT induction was 8.8 cm2 (area under the curve [AUC]: 0.86, 95% confidence interval [CI]: 0.75-0.97). The recurrence of AT at 36months in group N was 4.1% (5/122), and at the second ablation, all patients had macroreentrant AT. Patients with AT recurrence in group N had a wide LVA at the first ablation, and the cut-off LVA for AT recurrence was 6.5 cm2 (AUC 0.94, 95%CI 0.88-0.99). Adjusted multivariate analysis showed that only LVA size was associated with the recurrence of macroreentrant AT (odds ratio 1.21, 95%CI 1.04-1.51). It is important to develop a therapeutic strategy based on the LVA size to suppress the recurrence of AT in these patients.

Comparison of early rhythm control strategies in patients with atrial fibrillation: a nationwide population-based cohort study

Abstract Background Early rhythm control within 1-year after atrial fibrillation (AF) diagnosis is associated with a lower risk of major adverse cardiovascular event (MACE). Recently, AF catheter ablation (AFCA) using cryoballoon ablation as initial therapy has been demonstrated to be superior to drug therapy for the prevention of AF recurrence in patients with paroxysmal AF. However, there is still lack of evidence whether AFCA for the method of early rhythm control is superior to medical rhythm control therapy for the reduction of MACE risk. Purpose To evaluate the association between rhythm control treatment and the risk of MACE for early rhythm control in AF patients Methods Using a Korean nationwide claims database, patients with AF who received rhythm control therapy including antiarrhythmic agents (AAD), direct current cardioversion (DCC), and AF catheter ablation (AFCA, radiofrequency ablation or cryoballoon ablation) within 1-year after AF onset between 2011 and 2020 were included. According to rhythm control treatment, patients were categorized two groups as follow: (1) medical rhythm control group who prescribed AAD or underwent DCC, and (2) AFCA group who underwent radiofrequency or cryoballoon ablation. The primary outcome was MACE, the composite of ischemic stroke, admission for heart failure (HF), and myocardial infarction (MI). For the safety outcome, the composite of cardiac tamponade, syncope, sick sinus syndrome, atrioventricular block, pacemaker implantation, and sudden cardiac arrest was evaluated. Multivariable Cox regression analysis were performed. Results A total of 229,056 pateints were included (mean age 67.3±13.6 and 59.4% of men). Mean duration from new AF diagnosis to rhythm control treatment was 29.1±69.2 days. Among total, 221,952 patients received medical rhythm control and 7104 patients received AFCA. Compared to medical rhythm control group, AFCA group was associated with lower risks of ischemic stroke, admission for HF, and MI (adjusted hazard ratio [95% confidence interval]: 0.342 [0.287-0.408], p<0.001 for ischemic stroke, 0.356 [0.282-0.451], p<0.001 for admission for HF, and 0.640 [0.452-0.906], p=0.011 for MI) (Figure A). AFCA for early rhythm control showed a significantly lower risk of MACE than medical early rhythm control (0.328 [0.283-0.380], p<0.001, Figure A). Compared to medical rhythm control, AFCA showed a similar risk for safety outcome (1.197 [0.920-1.556], p=0.180). Among AFCA group, cryoballoon ablation showed comparable risks of ischemic stroke (0.465 [0.113-1.922], p=0.290), admission for HF (0.262 [0.035-1.936], p=0.189), MI (0.823 [0.100-6.767], p=0.856), and MACE (0.449 [0.164-1.228], p=0.118) with radiofrequency ablation (Figure B). Conclusion Regarding on the method of early rhythm control for AF, catheter ablation of AF might reduce the risk of MACE without a significant increase of safety outcome to medical rhythm control. Further results from randomized clinical trials are needed.

Predictive value of clinical risk scores for determination of left atrial low voltage area and arrhythmia recurrences in patients undergoing atrial fibrillation ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background Presence of left atrial low voltage area (LVA) is an independent predictor of atrial tachyarhythmia (ATa) recurrences after atrial fibrillation (AF) ablation. Thus identifying patients with LVA by using non-invasive methods is an important endeavour. Purpose In this study; we investigated the predictors of LVA and postablation recurrences especially focusing on clinical risk scores. Methods We enrolled 328 consecutive patients who underwent initial AF ablation procedure using high density mapping. LVAs were assessed and segmental distribution was noted in each patient. CHA2DS2-VASc, HATCH, APPLE and SPEED scores were calculated. Predictive value and arrhythmia recurrences were evaluated. Results Two hundred and twenty one patients (67.37%) were paroxysmal AF and 107 (32.62%) patients were non-paroxysmal AF at the time of ablation. Mean CHA2DS2-VASc score was 1.88±1.66, mean APPLE score was 1.20±1.20, HATCH score was 0.93±1.00 and SPEED score was 1.54±1.27 in the whole study group. LVA was detected in 131 patients (39.93%). Female gender [OR:2.94, CI: 1.34-6.43, p=0.007), non-paroxsymal AF (OR: 2.49 CI:1.13-5.46, p=0.023), APPLE score ≥1 (OR:1.69 CI:1.12-2.55, p=0.012) and SPEED score ≥ 1 (OR: 1.47 CI:1.00-2.14, p=0.045] were independent predictors for the presence of LVA in multivariate analysis. Presence of LVA (OR:1.98; CI:1.13-4.15; p=0.017) and HT (OR:2.00; CI:1.19-3.38; p=0.009) were the independent predictors of recurrences. Conclusion Higher clinical scores are associated with more LVA which is associated with ATa recurrence. However the predictive value of these risk scores is limited. Better risk scoring systems are needed to precisely identify the underlying atrial substrate in this patient group.

PO-02-170 EFFECT OF LOW DOSE COLCHICINE USE ON RECURRENCE OF ATRIAL FIBRILLATION AFTER CATHETER ABLATION

Colchicine is commonly used early after atrial fibrillation (AF) ablation to reduce AF recurrence, but there is limited efficacy data. To evaluate the effect of colchicine use on AF recurrence after ablation. From 2013 to 2021, all AF ablations performed at a single tertiary care medical center were analyzed for colchicine use, clinical and procedural characteristics, and AF recurrence. The colchicine dose was 0.3-0.6mg once daily. The primary outcome was AF recurrence, defined as AF detection for more than 30 seconds after a 3 month blanking period. Propensity score matching (PSM, 1:1 match) was performed using the covariates of gender, age, BMI, AF classification, hypertension (HTN), and diabetes mellitus (DM) based on significant predictors of AF recurrence in prior studies. The minimum duration of follow-up was 6 months. Kaplan-Meier analysis was conducted to assess time to AF recurrence in the entire cohort and the PSM cohort. The study population consisted of 1544 AF ablations in 1231 patients (67% male, age 65 ± 7 years and mean follow up 34 ± 14 months); 78% of the patients received colchicine. Baseline characteristics in colchicine vs no colchicine group showed males (65 vs 69%), mean age (67 vs 63 years), BMI (30 vs 31), paroxysmal AF (70 vs 82%), DM (16 vs 17%), HTN (60 vs 54%), and obstructive sleep apnea (OSA) (18 vs 19%). Colchicine use was associated with decreased AF recurrence (HR 0.78, CI 0.63-0.96, p=0.022; Figure 1A). After PSM, there were 275 patients in each group. Baseline characteristics were not significantly different between both groups. AF recurrence was lower with colchicine (HR 0.71, CI 0.53-0.96, p=0.026; Figure 1B). Colchicine use was associated with decreased AF recurrence in patients with paroxysmal AF (HR 0.70, CI 0.50-0.98, p=0.036) but not persistent AF (HR 0.79, CI 0.39-1.59, p=0.5). Colchicine use was associated with decreased AF recurrence in patients undergoing repeat AF ablation (HR 0.55, CI 0.32-0.96, p=0.036) but not de novo ablation (HR 0.77, CI 0.54-1.1, p=0.2). Colchicine use was associated with lower AF recurrence in patients undergoing AF ablation.

PO-02-067 PREDICTORS AND IMPACT OF PULMONARY VEIN NON-RECONNECTION IN THE SECOND PROCEDURE AFTER ABLATION INDEX-GUIDED PULMONARY VEIN ISOLATION FOR ATRIAL FIBRILLATION

Reconnection of the pulmonary vein (PV) is the primary mechanism of atrial tachyarrhythmia (AT) recurrence after atrial fibrillation (AF) ablation. In patients with AT recurrence after the first ablation index (AI)-guided AF ablation, we examined the predictors of PV non-reconnection and its impact on the outcome after the second procedure. We aimed to elucidate the predictor of PV non-reconnection and its impact on the outcome after the second ablation procedure. Among the consecutive 2089 patients undergoing the first AI-guided AF ablation, we studied 289 with AT recurrence undergoing the second procedure. We compared clinical characteristics and outcomes between the patient groups with and without PV reconnection at the beginning of the second procedure. Of the 289 patients, 134 (46%) had non-reconnection, while the other 155 (54%) had reconnection at least in one PV. Patients' characteristics, including AF type (paroxysmal AF, 41% versus 48%; persistent AF, 28% versus 26%; long-standing persistent AF, 31% versus 26%, respectively, P=0.50), were similar between the two groups. The percentage of first-pass PV isolation (FPI) in both PV sides in the first ablation procedure was significantly higher in PV non-reconnection than in those with reconnection group (77% versus 43%, respectively, p<0.001). Multivariate logistic regression analysis revealed that FPI at the first procedure (odds ratio, 0.23 (95% confidence interval (CI), 0.13-0.38), p<0.001) was the only independent predictor of PV reconnection. After the second procedure, Kaplan-Meier analysis revealed that AT recurrence rate was significantly higher in patients with PV non-reconnection than in those with reconnection (Log-rank test, p=0.005). Multivariate Cox proportional hazard model analysis revealed that PV non-reconnection (hazard ratio (HR), 1.71 (95%CI, 1.14-2.55), p=0.008), left atrial dimension (1.04 (1.01-1.07), p=0.006), and left ventricular ejection fraction (0.98 (0.96-0.99), p=0.005) were independent predictors of AT recurrence. However, AF type was not: HR to paroxysmal AF (reference) was 1.10 (95%CI, 0.67-1.83) (p=0.70) in persistent AF and 1.30 (0.82-2.03) (p=0.26) in long-standing persistent AF. FPI in the first procedure was the only independent predictor of PV non-reconnection. After the second procedure, PV non-reconnection was an independent worsening predictor of AT recurrence, suggesting a need for an aggressive search for non-PV mechanisms.

Predictive value of pre-procedural N-terminal pro-B-type natriuretic peptide level for atrial fibrillation recurrence after radiofrequency catheter ablation.

N-terminal pro-B-type natriuretic peptide (NT-proBNP) has been demonstrated as a valuable risk marker for mortality and morbidity of cardiovascular disease. Recurrence after atrial fibrillation (AF) radiofrequency catheter ablation remains common. We investigated the predictive value of the pre-procedural level of NT-proBNP to differentiate high-risk patients for post-ablation AF recurrence. 326 individuals with nonvalvular AF and preserved systolic function after enduring an initial radiofrequency catheter ablation (RFCA) between March 2018 and December 2019 were categorized into a recurrent group and a non-AF recurrent group. The serum NT-proBNP levels were examined before the ablation procedure. The researchers used multivariate logistic regression to find the determinants of AF recurrence. During a 14-month (interquartile range (IQR): 12-16) median follow-up, AF recurred in 84 (25.8%) patients. Patients in the recurrence group had considerably greater pre-ablation NT-proBNP levels (389.4 vs. 141.7 pg/ml, p < 0.001 in non-paroxysmal AF and 348.0 vs. 99.4 pg/ml, p < 0.001 in paroxysmal AF) as well as a greater left atrium (40 vs. 36 mm, p = 0.01 in non-paroxysmal AF and 38 vs. 36 mm, p = 0.01 in paroxysmal AF) than the non-AF recurrence group. A cut-off value of NT-proBNP ≥ 168.05 pg/ml identified AF recurrence with a sensitivity of 78.6% and specificity of 53.7% (area under ROC curve 0.68, 95% confidence interval (CI) 0.62-0.74, p < 0.001). Kaplan-Meier examination revealed that the elevated NT-proBNP (≥ 168.05 pg/ml) group presented a considerably shorter period without an occurrence compared to the low-NT-proBNP group (18.4 vs. 22.2 months, log-rank p = 0.001). Multivariate cox regression investigation showed that a level of NT-proBNP ≥ 168.05 pg/ml (hazard ratio (HR): 2.89, 95% CI: 1.71-4.903, p < 0.001) was a reliable predictor of AF recurrence after RFCA. A high pre-ablation NT-proBNP level was associated with AF recurrence, and it was also discovered to be a prognostic factor of recurrence of AF following RFCA.

Evaluating the value of the timing of recurrence during blanking period after atrial fibrillation ablation

Abstract Introduction In the first weeks after atrial fibrillation (AF) ablation, the arrythmia may recur theoretically due to transient local inflammation and not due to treatment failure. This is defined as the blanking period, with a proposed duration of 3 months. Recently, this time period has been brought into question. The aim of this work was to evaluate the correlation between the timing of blanking recurrence and late AF recurrence. Methods This was a single-centre retrospective study including patients without structural heart disease that underwent first AF ablation and were subsequently enrolled in the post ablation structured program between 2018 and 2021. Patients were excluded if they had &amp;lt;6 months follow-up. Appointment with ECG and Holter monitoring was performed at 1, 3, 6 and 12 months after ablation. Results We included a total of 193 patients (56% male, mean age 63±12 years). Of these, 79% had paroxysmal AF and mean left atrial volume index was 58±18 mL/m2. During the 3-month blanking period, there were 39 (21%) recurrences, 18 (9%) of which in the first month. After blanking period, at 6 months, 25 (13%) patients had AF recurrence, 56% of which had already recurred during blanking period. AF recurrence in the 2nd and 3rd month of blanking increased the odd of recurrence at 6-month by more than 5-fold (odds ratio (OR) 8,944; CI 95% 2,817–28,400, p&amp;lt;0.001 and OR 5,591; 95% CI 1,173–26,651; p=0.031). On the other hand, recurrence of AF during the 1st month of blanking was not associated with increased chance of 6-month AF recurrence (OR 2,095, 95% CI 0,630–6,964, p=0.227) (figure 1). There were no significant differences in clinical variables, including LA volume, between patients with 1-month recurrence and patients without recurrences. However, patients with AF recurrence in the 2nd and 3rd month of blanking had significantly increased LA volume. Conclusion Our study suggests that patients with AF recurrence in the 2nd and 3rd month of blanking have structurally different atria and are at a significantly higher risk of post blanking AF recurrence, in contrast with patients with AF recurrence in the 1st month of blanking, thus questioning the appropriate duration of the blanking period. Funding Acknowledgement Type of funding sources: None.

A new scoring system: PAT2C2H score. Its clinical use and comparison with HATCH and CHA2DS2-VASc scores in predicting arrhythmia recurrence after cryoballoon ablation of paroxysmal atrial fibrillation.

Several clinical risk factors and scoring systems have been proposed to predict arrhythmia recurrence after atrial fibrillation (AF) ablation. We sought to determine the ability of a new score to predict atrial arrhythmia recurrence after cryoballoon (CB) ablation of AF and whether the new score shows superior efficiency compared to previously offered scores. A total of 419 patients with paroxysmal AF who underwent their first CB ablation were included. Baseline clinical variables were analyzed, and independent predictors of recurrence at 12months were used to develop the PAT2C2H score. The predictive capability of the new score was calculated and compared with the currently available risk scores. Chronic obstructive pulmonary disease, left atrial dilatation, transient ischemic attack or stroke, congestive heart failure, and hypertension were independent predictors of recurrence. The PAT2C2H score which was developed from these variables had a better clinical predictive capability of arrhythmia recurrence compared to HATCH and CHA2DS2-VASc scores. With increasing PAT2C2H score and score severity (low, score of 0; moderate, score of 1-2; and high, score of ≥ 3), the proportion of patients with recurrence was increased from 7% (score = 0, severity = low) to 59% (score ≥ 3, severity = high). The PAT2C2H score may help to identify patients who are likely benefited most from CB ablation of paroxysmal AF and who should be monitored more closely for arrhythmia recurrence at 12months.

Impact of atrial fibrillation ablation on long-term outcomes in patients with tachycardia-bradycardia syndrome.

BackgroundReports of long‐term outcomes after atrial fibrillation (AF) ablation for tachycardia‐bradycardia syndrome (TBS) are limited. This study aimed to investigate the impact of radiofrequency catheter ablation (RFCA) on clinical outcomes in patients with TBS.MethodsAmong 1669 patients who underwent AF ablation between January 2010 and April 2020, we retrospectively enrolled 53 patients (62.3% males; age, 67.1 ± 7.0 years) who had been diagnosed with TBS before RFCA for paroxysmal AF (TBS group). After 1:2 propensity score‐matching based on age, gender, AF type, and left atrial dimension, 106 patients were assigned to the control group (non‐TBS group). The atrial tachyarrhythmia (ATA) recurrence rate and rate of avoidance of permanent pacemaker implantation (PMI) were examined.ResultsDuring a median follow‐up period of 37.7 months, the ATA recurrence rate after a single ablation procedure was significantly higher in the TBS group than in the non‐TBS group (51.0% vs. 38.5%; log‐rank p = .008); however, the ATA recurrence rate after the final ablation procedure did not significantly differ between groups. In the TBS group, the rate of PMI avoidance after AF ablation was 92.5%. A Cox‐regression multivariate analysis revealed that the presence of non‐pulmonary vein/superior vena cava premature atrial contractions (odds ratio, 3.38; 95% confidence interval, 1.49–7.66; p = .004) was an independent predictor of ATA recurrence in the TBS group.ConclusionsPatients with TBS had higher ATA recurrence rates after the first ablation procedure compared to those without TBS. However, ATA recurrence after AF ablation did not necessarily result in PMI for TBS patients.

Long Atrial Fibrillation Duration and Early Recurrence Are Reliable Predictors of Late Recurrence After Radiofrequency Catheter Ablation.

BackgroundRecurrence after atrial fibrillation (AF) ablation is still common.ObjectiveThis study aimed to evaluate the predictive abilities of AF duration and early recurrence (ER) to discriminate high-risk patients for recurrence.MethodsWe enrolled 1,763 consecutive patients with AF who were scheduled to receive the index radiofrequency catheter ablation (RFCA) from January 2016 to August 2021 in Dalian, China. Long AF duration (LAFD) was considered if the course of AF lasted for ≥ 12 months. ER was defined as any atrial tachycardia (AT) or AF event longer than 30 s occurring within a 3-month post-RFCA.ResultsLate recurrence occurred in 643 (36.5%) of the 1,763 patients at a median of 35 months after RFCA. Multivariate analysis identified LAFD (hazard ratio (HR): 1.80, 95% confidence interval (CI): 1.38–2.35, p < 0.001) and ER (HR: 2.34, 95% CI: 1.82–3.01, p < 0.001) as strong independent predictors of late recurrence in non-paroxysmal AF. Similarly, LAFD (HR: 1.48, 95% CI: 1.20–1.84, p < 0.001) and ER (HR: 3.40, 95% CI: 2.68–4.30, p < 0.001) were significantly associated with late recurrence in paroxysmal AF. Receiver operating curve analyses revealed that the CAAP-AF (CAD, Atrial diameter, Age, Persistent or longstanding AF, Antiarrhythmic drugs failed, Female) had the highest predict power [area under ROC curve (AUC) 0.586]. The addition of ER and LAFD to the CAAP-AF score significantly improved risk discrimination for late recurrence after AF ablation from 0.586 to 0.686.ConclusionLong AF duration and ER were independently associated with late recurrence. The prediction performance of the CAAP-AF model for recurrence was improved by the addition of LAFD and ER.

Sex difference in atrial fibrillation recurrence after catheter ablation and antiarrhythmic drugs

ObjectiveThe risk of recurrence after atrial fibrillation (AF) catheter ablation (AFCA) is higher in women than in men. However, it is unknown whether a sex difference exists in antiarrhythmic drug...

Antiarrhythmic drug therapy after catheter ablation for atrial fibrillation has no impact on recurrences, cardiovascular events and mortality – insights from the German Ablation Registry

Abstract Background Data on the optimal treatment strategy for antiarrhythmic drug therapy (AAD) after atrial fibrillation (AF) catheter ablation are inconsistent. While AAD potentially stabilizes sinus rhythm, it also increases the patients' treatment burden. Methods Patients from the prospective German Ablation Registry (n=3275) discharged with or without AAD after AF catheter ablation were compared regarding long-term success, cardiovascular events and patient reported outcome. Results In patients with paroxysmal AF (n=2138) recurrence and rehospitalization rates did not differ when discharged with (n=1051) or without (n=1087) AAD (recurrence: adjusted odds ratio (OR) 1.13, 95% confidence interval (CI) [0.95–1.35]; rehospitalization: OR 1.08, 95% CI [0.90–1.30]). The reablation rate was higher and reduced treatment satisfaction was reported more often in those discharged with AAD (reablation: OR 1.30, 95% CI [1.05–1.61]; reduced treatment satisfaction: OR 1.76, 95% CI [1.20–2.58]). Similar rates of recurrences, rehospitalisations, reablations and treatment satisfaction were found in patients with persistent AF (n=1137) discharged with (n=641) or without (n=496) AAD (recurrence: OR 1.22, 95% CI [0.95–1.56]; rehospitalization: OR 1.16, 95% CI [0.90–1.50]; reablation: OR 1.21, 95% CI [0.91–1.61]; treatment satisfaction: OR 1.24, 95% CI [0.74–2.08]). The incidence of cardiovascular events and mortality did not differ at follow-up in paroxysmal and persistent AF patients discharged with or without AAD. Conclusion The rates of recurrences, cardiovascular events and mortality did not differ between patients discharged with or without AAD after AF catheter ablation. However, AAD should be considered carefully in patients with paroxysmal AF, in whom it was associated with a higher reablation rate and reduced treatment satisfaction. Funding Acknowledgement Type of funding sources: None.

Does atrial fibrillation ablation worsen preexisting anemia? Another anemia paradox in DOAC era

BackgroundThere is a concern about worsening anemia after atrial fibrillation (AF) ablation in anemic patients. We aimed to clarify whether or not patients with anemia who are on an oral anticoagulant therapy are more likely to lose blood after AF ablation. MethodsWe studied AF patients in 3 cardiovascular centers who skipped a single dose of a direct oral anticoagulant prior to the ablation, and compared the drop in the hemoglobin level 24 hours after the procedure and bleeding complications between the patients with and without preexisting anemia. ResultsWe identified 183 (15.7%) patients with anemia at baseline out of 1163 patients. The reduction in the hemoglobin level (-0.39±0.71 vs. -0.93±0.9 g/dL; p<0.001) was smaller in the anemic than non-anemic patients. A fall in the hemoglobin level of ≥2 g/dL, which is a guideline-defined significant hemoglobin drop, was less common in anemic patients (1.6% vs. 11.3%; p<0.001). A female gender [odds ratio (OR) 1.62, confidence interval (CI) 1.07-2.45; p=0.02], persistent or long-standing persistent versus paroxysmal AF (OR 1.67, CI 1.13-2.49; p=0.01), ORBIT score ≥3 (OR 3.5, CI 1.34-8.94; p=0.01), and preexisting anemia (OR 0.02, CI 0.004-0.14; p<0.001) were independently associated with the fall in the hemoglobin level of ≥2 g/dL. No difference was noted in the rate of major bleeding complications (1.6% vs. 1.2%; p=0.72). ConclusionsParadoxically, patients with preexisting anemia may be less likely to lose blood following AF ablation.

Quantification of Left Atrial Fibrosis in Patients After Pulmonary Vein Isolation Using the Second-Generation Cryoballoon

Left atrial (LA) fibrosis is associated with a poor outcome after atrial fibrillation (AF) ablation. This study examined the extent of low-voltage areas in patients with recurrence of atrial tachyarrhythmia (ATA) after CB-based pulmonary vein isolation (PVI).Sixty patients (mean age 67 ± 10 years, n = 32 female; n = 34 paroxysmal AF) who received radiofrequency redo-procedure due to recurrence of ATA within 6 months after CB-based PVI were included. A point-by point 3D-map was performed, and low-voltage sites were delineated based on bipolar voltage < 0.5 mV. The extent of fibrosis was categorized as stage A (0-10% of the LA wall), stage B (10-30%), stage C (30-50%), and stage D (> 50%).The median area of LA low-voltage sites was 28.9 (9; 50.3) cm2, corresponding to 17.4 (6; 30.6) % of the LA wall surface. 17/60 (28.3%) patients were categorized as fibrosis stage A, 21/60 (35%) as stage B, 18/60 (30%) as stage C, and 4/60 (6.7%) as stage D. Patient age and LA diameter were associated with more pronounced LA fibrosis; the extent of LA fibrosis was significantly higher in patients with LA tachycardia (LAT) during redo-procedures (P < 0.01), and ablation of linear lesions was more often performed (P < 0.01).In patients after CB2-based PVI, expanded LA tissue fibrosis was associated with the occurrence of LAT and more extensive LA ablation during redo-procedures.

Clinical relationship between anemia and atrial fibrillation recurrence after catheter ablation without genetic background

BackgroundAnemia is a known adverse prognostic factor among patients with cardiovascular diseases. We investigated whether the hemoglobin level was associated with the rhythm outcome after atrial fibrillation (AF) catheter ablation (AFCA). MethodsWe included 2627 patients who underwent AFCA and a guidelines-based rhythm follow-up (age 58 ± 10.9 years, 73% men, 30.6% with persistent AF), and evaluated the association of pre-AFCA anemia (haemoglobin <13 g/dL in men and <12 g/dL in women) and rhythm outcomes. We studied the mechanistic relationship between anemia and AF recurrence using a Mendelian randomization analysis (1775 subjects with genome-wide association study) after reviewing already proven 12 hemoglobin-associated genetic polymorphisms. ResultsThe body mass index, paroxysmal AF, warfarin use, and baseline red cell distribution width were independently associated with anemia in patients with AF. During a 23-month follow-up (interval OR 9–48 months), the clinical AF recurrence rate was significantly higher in patients with than without anemia (log-rank p = 0.001; propensity score-matched log-rank p = 0.004). This pattern was more significant in male patients (Log-rank p < 0.001) or patients with paroxysmal AF (Log-rank p < 0.001). Anemia (hazard ratio [HR] 1.45 [1.17–1.80], p = 0.001), left atrial diameter (HR 1.03 [1.01–1.04], p < 0.001), a female sex (HR 1.17 [1.00–1.36], p = 0.047), and persistent AF (HR 1.58 [1.36–1.84], p < 0.001) were independently associated with post-AFCA clinical recurrence. In the Mendelian randomization, we could not find a significant direct causal relationship between anemia and AF recurrence at the genetic level. ConclusionsPre-AFCA anemia is an independent predictor of post-AFCA clinical recurrence, especially in male patients, without a genetically direct causal relationship.

Safety of Same Day Discharge after Atrial Fibrillation Ablation.

It is routine practice to observe patients (pts) overnight in the hospital after atrial fibrillation (AF) ablation. We report single center experience comparing the rate of complications prior to and after implementing a strategy of same day discharge (SDD) following AF ablation. To assess the safety of SDD after AF ablation. We reviewed the charts of consecutive pts who underwent AF ablation between Jan 2005 to Dec 2015. Patients who were electively admitted to undergo AF ablation or left atrial flutter ablation (AFL) were included. Patients undergoing only right atrial flutter ablation and in-patients were excluded. In Sept 2012 SDD strategy was implemented. Complication rates were collected up to 3 months post ablation. Major complications were defined as death, pericardial tamponade, CVA, hematoma requiring intervention, pulmonary vein stenosis, diaphragmatic paralysis or atrioesophageal fistula formation. Minor complications were defined as hematoma not requiring intervention and procedure related readmissions. Comparisons were made using an intention to treat analysis. Group A (between Jan 2005 to Feb 2010) included 145 patients (87 males; 60.2 yrs mean age; 103 paroxysmal AF) who were observed overnight. Group B (between Mar 2010 to Dec 2015) included 426 patients (298 males; 62.3 yrs mean age; 247 paroxysmal AF) undergoing ablation following implementation of the SDD strategy. Patients in Group B were contacted by phone next day. In Group B, 51/426 (12%) pts were not discharged same day due to non-ablation related medical care (15/50 pts), ablation related complications (17/50 pts), pt preference (14/50 pts) and late cases (5/50 pts). Rate of total complications was more frequent in Group A (Group A 11.7% vs Group B 4.4%; p 0.026). Major complications happened in 2 pts in Group A and 6 pts in Group B. None of the major complications in Group B happened within 24 hrs of discharge. Only one pt in Group B had pericardial effusion drained 10 days post procedure. Most common minor complication in Group A was hematoma not requiring intervention and Group B was procedure related readmissions. Our data suggest that SDD after AF or AFL ablation can be safely implemented in majority of pts with similar outcomes as pts observed overnight.

Diagnostic value of implantable loop recorder in patients undergoing cryoballoon ablation of atrial fibrillation.

BackgroundDue to limited data, implantable loop recorders (ILR) are not currently recommended by the guidelines to routinely monitor patients after atrial fibrillation (AF) ablation.AimsTo validate the diagnostic value of ILR after AF ablation, modern generation ILRs (LINQ) were implanted in patients scheduled for cryoballoon ablation of AF (CBA).MethodsWe included 29 patients with frequent and symptomatic episodes of paroxysmal AF. ILR was implanted 3 months prior to CBA, and data were collected before and for 6 months after the procedure. The device was programmed to maximize sensitivity of AF/ atrial tachycardia (AT) detection. All EGM recordings were “manually” assessed and annotated as true AF, pseudo AF, unrecognized AF, and episodes with no EGM available. Duration and episode‐based standard performance metrics were evaluated.ResultsA total number of 5,842 episodes were recorded. A total of 4,403 episodes were true AF, 453 episodes were pseudo AF, and 986 episodes had no EGM available. The device did not recognize 144 episodes of AF. Duration‐based sensitivity was 95.2%, duration‐based specificity 99.9%, duration‐based PPV 99.2%, duration‐based NPV 99.9%, episode‐based sensitivity 98.0%, and episode‐based PPV 91.0%. Misdiagnosis happened in 1 in 10 episodes. Total data review time was 166 hr.ConclusionsImplantable loop recorders is a valuable tool in evaluation of AF episodes in patients undergoing CBA. However, for high precision all recorded episodes need to be evaluated “manually.” The memory storage space is too low for frequent AF episodes, resulting in overwriting of stored EGMs and data loss.

Cryoballoon or Radiofrequency Ablation for Atrial Fibrillation Assessed by Continuous Monitoring: A Randomized Clinical Trial.

Advanced generation ablation technologies have been developed to achieve more effective pulmonary vein isolation (PVI) and minimize arrhythmia recurrence after atrial fibrillation (AF) ablation. We randomly assigned 346 patients with drug-refractory paroxysmal AF to contact force-guided radiofrequency ablation (CF-RF; n=115), 4-minute cryoballoon ablation (Cryo-4; n=115), or 2-minute cryoballoon ablation (Cryo-2; n=116). Follow-up was 12 months. The primary outcome was time to first documented recurrence of symptomatic or asymptomatic atrial tachyarrhythmia (AF, atrial flutter, or atrial tachycardia) between days 91 and 365 after ablation or a repeat ablation procedure at any time. Secondary end points included freedom from symptomatic arrhythmia and AF burden. All patients received an implantable loop recorder. One-year freedom from atrial tachyarrhythmia defined by continuous rhythm monitoring was 53.9%, 52.2%, and 51.7% with CF-RF, Cryo-4, and Cryo-2, respectively (P=0.87). One-year freedom from symptomatic atrial tachyarrhythmia defined by continuous rhythm monitoring was 79.1%, 78.2%, and 73.3% with CF-RF, Cryo-4, and Cryo-2, respectively (P=0.26). Compared with the monitoring period before ablation, AF burden was reduced by a median of 99.3% (interquartile range, 67.8%-100.0%) with CF-RF, 99.9% (interquartile range, 65.3%-100.0%) with Cryo-4, and 98.4% (interquartile range, 56.2%-100.0%) with Cryo-2 (P=0.36). Serious adverse events occurred in 3 patients (2.6%) in the CF-RF group, 6 patients (5.3%) in the Cryo-4 group, and 7 patients (6.0%) in the Cryo-2 group, with no significant difference between groups (P=0.24). The CF-RF group had a significantly longer procedure duration but significantly shorter fluoroscopy exposure (P<0.001 vs cryoballoon groups). In this multicenter, randomized, single-blinded trial, CF-RF and 2 different regimens of cryoballoon ablation resulted in no difference in 1-year efficacy, which was 53% by time to first recurrence but >98% burden reduction as assessed by continuous cardiac rhythm monitoring. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01913522.

Predictors and Incidence of Atrial Flutter After Catheter Ablation of Atrial Fibrillation

Atrial flutter (AFL) is a common form of arrhythmia recurrence after atrial fibrillation (AF) ablation. We aimed to define (1) the incidence of AFL and (2) the clinical factors associated with cavo-tricuspid isthmus dependent (typical) and atypical AFL, after AF ablation. The retrospective cohort consisted of 1,029 patients that underwent initial radiofrequency AF ablation from May 2005 to December 2013 at a single academic center. Patients with missing follow-up data, history of AFL ablation, and those with undocumented AFL were excluded. Atrial volumes were measured using three-dimensional cardiac computed tomography or magnetic resonance imaging. A total of 607 patients were included in the final cohort (age 59.2 ± 10.6 years, 76.0% men, 58.7% paroxysmal AF). During a median follow-up of 845 days (interquartile range 389 to 1,597 days), 122 (20.1%) patients developed AFL. Of these, 17 had typical AFL, 98 had atypical AFL, and 7 patients had both circuits. In the multivariable Cox regression analysis, only right atrial volume index (hazard ratio [HR] 1.25 per 10 ml/m2, confidence interval [CI] 95% 1.10 to 1.42) was associated with incident typical AFL; whereas persistent AF (HR 1.59, CI 95% 1.06 to 2.40), linear lesions (HR 1.58, CI 95% 1.02 to 2.46) and left atrial volume index (HR 1.17 per 10 ml/m2, CI 95% 1.07 to 1.27) were associated with incident atypical AFL. In conclusion, noninvasive measures of right and left atrial remodeling are strongly associated with incident AFL after AF ablation. Strategies to prevent incident AFL using these measures after index ablation warrant further investigation.

Diagnosis‐to‐ablation time in atrial fibrillation: A modifiable factor relevant to clinical outcome

Recurrences after atrial fibrillation (AF) ablation are still common. Among the reported clinical and imaging predictors of recurrences, diagnosis-to-ablation time (DAT) has been defined as a predictor of ablation outcome in single-center studies. We aimed to validate DAT in a multicenter real-life cohort. This was a multicenter study including consecutive patients undergoing first paroxysmal and persistent AF ablation with radiofrequency or cryoballoon catheters during 2013. Cox proportional hazard regression models were performed to identify predictors of recurrence. In total, 309 patients were included across nine centers (71% men, 57 ± 10 years old, 46% with hypertension, and 66% with CHA2 DS2 -VASc ≤ 1). Most patients had paroxysmal AF (67%) and underwent radiofrequency ablation (68%) with a median DAT of 51 (43) months. Patients with DAT ≤ 1 year (16.6%) were less likely to have repeat procedures (4% vs 18%; P = .017). The adjusted proportional hazards Cox model identified hypertension (P = .005), heart failure (P = .011), nonparoxysmal AF (P = .038), DAT > 1 year (P = .007), and LA diameter (P = .026) as independent predictors for AF recurrence. DAT > 1 year was the only modifiable factor independently associated with recurrence (HR 4.2 [95% CI, 1.5-11.9]) CONCLUSION: Diagnosis-to-ablation time is a modifiable factor independently associated with recurrent arrhythmia and repeat ablation after first AF ablation. An early intervention strategy during the first year from AF diagnosis might improve outcomes.