Outcome Of Catheter Ablation For Atrial Fibrillation Research Articles

The Impact of Gastroesophageal Reflux Disease and Proton Pump Inhibitor Use on the Risk of Repeat Catheter Ablation for Atrial Fibrillation.

Gastroesophageal reflux disease (GERD) has been associated with increased incidence/recurrence of atrial fibrillation (AF). However, the impact of GERD and proton pump inhibitor (PPI) therapy on outcomes of AF catheter ablation remains unclear. We aimed to assess the association between the presence of GERD and risk of repeat AF ablation, stratified by PPI therapy. A retrospective cohort study was conducted on paroxysmal/persistent AF patients undergoing initial ablation in 1/2011-9/2015. GERD was defined by endoscopic findings, objective reflux testing, or clinical symptoms. The association between GERD/PPI use and time to repeat ablation was evaluated by time-to-event analysis with censoring at last clinic follow-up within one year. 381 subjects were included. GERD patients (n=80) had a higher one-year repeat ablation rate compared to no GERD (25% vs 11.3%, p=0.0034). Stratifying by PPI use, untreated GERD patients (37.5%) more likely needed repeat ablation compared to reflux-free (11.3%, p=0.0003) and treated GERD (16.7%, p=0.035) subjects. On multivariable Cox regression analyses, GERD was an independent risk factor for repeat ablation (HR 3.30, CI:1.79-6.08, p=0.0001). Specifically, untreated GERD was associated with earlier repeat ablation compared to those with no GERD (HR 4.02, CI:1.62-12.05, p=0.0013). However, no significant difference in repeat ablation risk was noted between reflux-free and PPI-treated GERD groups. GERD was an independent predictor for risk of repeat AF ablation within one year, even after controlling for major cardiovascular comorbidities and confounders. PPI therapy modulated this risk, as repeat ablation-free survival for PPI-treated GERD was non-inferior to reflux-free patients.

Atrial Fibrillation Catheter Ablation among Cancer Patients: Utilization Trends and In-Hospital Outcomes.

Background: Atrial fibrillation (AF) catheter ablation in cancer patients has been evaluated in very few studies. We aimed to investigate utilization trends and in-hospital outcomes of AF catheter ablation among cancer patients in a large US inpatient registry. Methods: Utilizing the National Inpatient Sample (NIS) database, patients who underwent AF catheter ablation between 2012 and 2019 were identified. Sociodemographic, clinical data, in-hospital procedures and outcomes were collected. Baseline characteristics and in-hospital outcomes were compared between patients with and without cancer. Results: An estimated total of 67,915 patients underwent AF catheter ablation between 2012 and 2019 in the US. Of them, 950 (1.4%) had a cancer diagnosis. Patients with a cancer diagnosis were older and had higher Charlson Comorbidity Index, CHA2DS2-VASc and ATRIA bleeding indices scores. A higher rate of total complications was observed in cancer patients (10.5% vs. 7.9, p < 0.001), driven mainly by more bleeding and infectious complications. However, no significant differences in cardiac or neurological complications as well as in-hospital mortality rates were observed and were relatively low in both groups. Conclusions: AF catheter ablation in cancer patients is associated with higher bleeding and infectious complication rates, but not with increased cardiac complications or in-hospital mortality in a US nationwide, all-comer registry.

Catheter ablation of atrial fibrillation in patients with and without hypertrophic cardiomyopathy: systematic review and meta-analysis.

Atrial fibrillation (AF) is common in hypertrophic cardiomyopathy (HCM). There is limited data regarding the outcomes of AF catheter ablation in HCM patients. In this study, we aimed to synthesize all available evidence on the effectiveness of ablation of AF in patients with HCM compared to those without HCM. We systematically reviewed bibliographic databases to identify studies published through February 2023. We included cohort studies with available quantitative information on rates of recurrent atrial arrhythmias, anti-arrhythmic drug (AAD) therapy, and repeat ablation procedures after initial AF ablation in patients with vs without HCM. Estimates were combined using random-effects meta-analysis models and reported as risk ratios (RR) and 95% confidence intervals (CI). Eight studies were included in quantitative synthesis (262 HCM and 642 non-HCM patients). During median follow-up 13-54 months across studies, AF recurrence rates ranged from 13.3% to 92.9% in HCM and 7.6% to 58.8% in non-HCM patients. The pooled RR for recurrent atrial arrhythmia after the first AF ablation in HCM patients compared to non-HCM controls was 1.498 (95% CI = 1.305-1.720; P < 0.001). During follow-up, HCM patients more often required AAD therapy (RR = 2.844; 95% CI = 1.713-4.856; P < 0.001) and repeat AF ablation (RR = 1.544; 95% CI = 1.070-2.228; P = 0.02). The pooled RR for recurrent atrial arrhythmias after the last AF ablation was higher in patients with HCM than those without HCM (RR = 1.607; 95% CI = 1.235-2.090; P < 0.001). Compared to non-HCM patients, those with HCM had higher rates of recurrent atrial arrhythmias, AAD use, and need for repeat AF ablation after initial ablation of AF.

Adverse outcomes of atrial fibrillation ablation in heart failure patients with and without cardiac amyloidosis: a Nationwide Readmissions Database analysis (2015-2019).

Atrial fibrillation (AF) in patients with cardiac amyloidosis (CA) has been linked with a worse prognosis. The current study aimed to determine the outcomes of AF catheter ablation in patients with CA. The Nationwide Readmissions Database (2015-2019) was used to identify patients with AF and concomitant heart failure. Among these, patients who underwent catheter ablation were classified into two groups, patients with and without CA. The adjusted odds ratio (aOR) of index admission and 30-day readmission outcomes was calculated using a propensity score matching (PSM) analysis. A total of 148 134 patients with AF undergoing catheter ablation were identified on crude analysis. Using PSM analysis, 616 patients (293 CA-AF, 323 non-CA-AF) were selected based on a balanced distribution of baseline comorbidities. At index admission, AF ablation in patients with CA was associated with significantly higher adjusted odds of net adverse clinical events (NACE) [adjusted odds ratio (aOR) 4.21, 95% CI 1.7-5.20], in-hospital mortality (aOR 9.03, 95% CI 1.12-72.70), and pericardial effusion (aOR 3.30, 95% CI 1.57-6.93) compared with non-CA-AF. There was no significant difference in the odds of stroke, cardiac tamponade, and major bleeding between the two groups. At 30-day readmission, the incidence of NACE and mortality remained high in patients undergoing AF ablation in CA. Compared with non-CA, AF ablation in CA patients is associated with relatively higher in-hospital all-cause mortality and net adverse events both at index admission and up to 30-day follow-up.

Prevalence and clinical impact of major incidental findings detected on routine cardiovascular resonance imaging prior to catheter ablation of atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background Preprocedural contrast-enhanced cardiovascular magnetic resonance (CMR) or computed tomography (CT) imaging of the left atrium (LA) and pulmonary veins (PVs) is usually employed to facilitate catheter mapping and ablation of atrial fibrillation (AF). Incidental findings (IFs) are common on cardiac imaging prior to AF catheter ablation (AFCA). However, previous studies were of small size and have mainly focused on radiological extracardiac IFs detected on preprocedural CT scan. Purpose To assess the prevalence of major cardiac and extracardiac IFs on routine preprocedural CMR in a large cohort of consecutive patients scheduled for first-time AFCA, and to report its impact on clinical decision-making and management. Methods All consecutive patients who underwent routine preprocedural CMR prior to first-time AFCA between April 2015 and March 2019 were considered for analysis. Main exclusion criteria were referral for repeat AFCA; prior cardiac CT or CMR imaging; and general contraindication to CMR or AFCA. All CMR examinations consisted of survey images with full thoracic coverage, cardiac cine and late-gadolinium enhancement imaging, and three-dimensional contrast-enhanced CMR angiography of the LA/PVs. An IF was defined as major when any newly detected finding either resulted in cancellation of the AFCA procedure or intentional deviation from the standard AFCA protocol. In patients with accessory or anomalous PVs the ablation strategy was individually tailored aiming at isolation of all PVs. Results Two thousand consecutive patients (62±10 years; 59% male) with paroxysmal (48%) or persistent (52%) AF were included. Among the entire study cohort 172 patients (8.6%) had a total of 184 cardiac (75%) and extracardiac (25%) major IFs (Fig. A+B). Preprocedural detection of a major IF resulted in cancellation of the scheduled AFCA procedure in 88 patients (4.4%). Forty-two patients (2.1%) have thereupon never been ablated, 46 patients (2.3%) underwent postponed AFCA after a median time from CMR imaging of 83 (32-213) days. The remaining 84 patients with major IF (4.2%) underwent an individualized approach to AFCA (Fig. A). The most common major IFs were accessory or anomalous PVs in 76 (3.8%), extracardiac abnormalities suspicious of malignancy in 29 (1.5%), and positive stress perfusion imaging in 19 (1.0% overall; 7.2% of 261 tested) patients. In 19 patients (1.0%) preprocedural CMR detected a previously unknown intracardiac thrombus or structural cardiac disease. Conclusion Unexpected major IFs on routine preprocedural CMR affected clinical decision-making and therapeutic management in 8.6% of patients scheduled for first-time AFCA at our institution. Whether preprocedural CMR imaging may improve safety and outcome of AFCA needs to be addressed in future research.

Association of ZFHX3 genetic polymorphisms and extra-pulmonary vein triggers in patients with atrial fibrillation who underwent catheter ablation

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Health and Welfare, National Research Foundation of Korea (NRF) Abstract Background The ZFHX3 gene (16q22) is the second most highly associated gene with atrial fibrillation (AF) and is related to inflammation and fibrosis. Purpose We hypothesized that ZFHX3 is associated with extra-pulmonary vein (PV) triggers, left atrial (LA) structural remodeling, and poor rhythm outcomes of AF catheter ablation (AFCA). Methods We included 1782 patients who underwent a de novo AFCA (73.5% male, 59.4±10.8 years old, 65.9% paroxysmal AF) and genome-wide association study and divided them into discovery (n=891) and replication cohorts (n=891). All included patients underwent isoproterenol provocation tests and LA voltage mapping. We analyzed the ZFHX3, extra-PV trigger-related factors, and rhythm outcomes. Results Among 14 single-nucleotide polymorphisms (SNPs) of ZFHX3, rs13336412, rs61208973, rs2106259, rs12927436, and rs1858801 were associated with extra-PV triggers. In the overall patient group, extra-PV triggers were independently associated with the ZFHX3 polygenic risk score (PRS) (OR 1.65 [1.22-2.22], p=0.001, model 1) and a low LA voltage (OR 0.74 [0.56-0.97], p=0.029, model 2). During 49.9±40.3 months of follow-up, clinical recurrence of AF was significantly higher in patients with extra-PV triggers (Log-rank p&amp;lt;0.001, HR 1.89 [1.49-2.39], p&amp;lt;0.001, model 1), large LA dimensions (Log-rank p&amp;lt;0.001, HR 1.03 [1.01-1.05], p=0.002, model 2), and low LA voltages (Log-rank p&amp;lt;0.001, HR 0.73 [0.61-0.86], p&amp;lt;0.001, model 2) but not the ZFHX3 PRS (Log-rank p=0.819). Conclusions The extra-PV triggers had significant associations with both ZFHX3 genetic polymorphisms and acquired LA remodeling. Although extra-PV triggers were an independent predictor of AF recurrence after AFCA, the studied AF risk SNPs intronic in ZFHX3 were not associated with AF recurrence.

Abstract 179: Impact Of Age On Catheter Ablation For Atrial Fibrillation In Octogenarians

Introduction: Patients undergoing catheter ablation for atrial fibrillation (CA-AF) often have significant co-morbidities. Although multiple comorbidities increase with age, outcomes of CA-AF), particularly, in older patients has been conflicting. Methods: The International Classification of Diseases Code, 10 th Revision Clinical Modification (ICD-10) was used to identify patients hospitalized for CA-AF between 2016-2019 from the National Readmission database (NRD). Patients were classified into two groups, those younger than 80 years and older than 80 years. Ninety-day readmission rates and causes of readmission were compared. Adjusted multivariate regression analysis was used to identify factors associated with readmissions. Results: We identified 40,174 patients who underwent CA-AF from this cohort, 5875 (14.6%) patients were above the age of 80 years and these patients were more likely to have congestive heart failure (72.8% vs 42.6 %), valvular disease (39.3% vs 20.4), pulmonary vascular disorders (18.5% vs 7.4%), chronic pulmonary disease (29.9% vs 23%) and renal failure (35.7% vs 16.6%). In addition, patients &gt;80 years had longer hospital length of stay, higher rates of major adverse cardiovascular events (6.4% vs 3.5%; p&lt;0.0001), acute heart failure and sepsis during their index admission when compared with patients &lt; 80 years. A total of 1201 (20.4%) patients above age for 80 years were readmitted within 90 days as compared to 4295 (12.5%) below the age of 80 years ( p&lt;0.001). Acute heart failure, AF and acute kidney injury were the most common causes for readmission. The following factors were associated with higher risk of readmission in multivariate regression analysis: length of stay &gt; 4 days (OR 1.36 95% CI 1.17-1.91, P&lt;0.0001), chronic pulmonary disease (OR 1.35 95%1.17-1.55, P&lt;0.0001) and renal failure (OR 1.25 95% CI 1.006-1.55, p=0.04). Conclusion: Age &gt; 80 years is associated with increased risk of complications and higher readmission post CA-AF in patients with OSA . Shared medical decision making for octogenarians with AF should consider these data and alternative treatment strategies when appropriate.

Impact of Preoperative Nutritional Status on the Outcome of Catheter Ablation for Atrial Fibrillation.

The relationship between nutritional status and the incidence or prognosis of atrial fibrillation (AF) has been reported, but no studies have described the relationship between the outcomes of AF catheter ablation (CA) and nutritional status as assessed by various scoring tools. We aimed to verify the hypothesis that preoperative nutritional status is associated with arrhythmia recurrence after CA for AF.Methods and Results:We evaluated 913 patients (age, 67±10 years; men, 72%; paroxysmal AF, 56%) who underwent CA for AF between November 2011 and November 2017. Patients were systematically followed with an endpoint of atrial tachyarrhythmia recurrence, the predictive value of which was compared among 3 scoring tools (Controlling Nutritional Status [CONUT] score / Geriatric Nutritional Risk Index [GNRI] / Prognostic Nutritional Index [PNI]). Patients were divided into normal nutrition (CONUT <2 [n=637] / GNRI >98 [n=836] / PNI >38 [n=910]) and undernutrition (CONUT ≥2 [n=276] / GNRI ≤98 [n=77] / PNI ≤3 [n=3]) groups. AF recurred in 274 patients (mean follow-up, 2.3±0.8 years). The AF recurrence rate was higher in patients with undernutrition than in those with normal nutrition (CONUT/GNRI) status. Multivariate Cox regression analysis identified undernutrition status (GNRI ≤98) as an independent predictor of atrial tachyarrhythmia recurrence. The AF recurrence rate after CA was higher in patients with undernutrition than in those with normal nutrition as stratified by the nutrition scoring tools.

Association of ZFHX3 Genetic Polymorphisms and Extra-Pulmonary Vein Triggers in Patients With Atrial Fibrillation Who Underwent Catheter Ablation.

Background: The ZFHX3 gene (16q22) is the second most highly associated gene with atrial fibrillation (AF) and is related to inflammation and fibrosis. We hypothesized that ZFHX3 is associated with extra-pulmonary vein (PV) triggers, left atrial (LA) structural remodeling, and poor rhythm outcomes of AF catheter ablation (AFCA).Methods: We included 1,782 patients who underwent a de novo AFCA (73.5% male, 59.4 ± 10.8 years old, 65.9% paroxysmal AF) and genome-wide association study and divided them into discovery (n = 891) and replication cohorts (n = 891). All included patients underwent isoproterenol provocation tests and LA voltage mapping. We analyzed the ZFHX3, extra-PV trigger-related factors, and rhythm outcomes.Result: Among 14 single-nucleotide polymorphisms (SNPs) of ZFHX3, rs13336412, rs61208973, rs2106259, rs12927436, and rs1858801 were associated with extra-PV triggers. In the overall patient group, extra-PV triggers were independently associated with the ZFHX3 polygenic risk score (PRS) (OR 1.65 [1.22–2.22], p = 0.001, model 1) and a low LA voltage (OR 0.74 [0.56–0.97], p = 0.029, model 2). During 49.9 ± 40.3 months of follow-up, clinical recurrence of AF was significantly higher in patients with extra-PV triggers (Log-rank p < 0.001, HR 1.89 [1.49–2.39], p < 0.001, model 1), large LA dimensions (Log-rank p < 0.001, HR 1.03 [1.01–1.05], p = 0.002, model 2), and low LA voltages (Log-rank p < 0.001, HR 0.73 [0.61–0.86], p < 0.001, model 2) but not the ZFHX3 PRS (Log-rank p = 0.819).Conclusion: The extra-PV triggers had significant associations with both ZFHX3 genetic polymorphisms and acquired LA remodeling. Although extra-PV triggers were an independent predictor of AF recurrence after AFCA, the studied AF risk SNPs intronic in ZFHX3 were not associated with AF recurrence.

Risk Factors for Stiff Left Atrial Physiology 1 Year After Catheter Ablation of Atrial Fibrillation.

Catheter ablation is the most effective rhythm control method for patients with atrial fibrillation (AF); however, it inevitably causes atrial tissue damage. We previously reported that AF catheter ablation (AFCA) increases left atrial (LA) pressure without changes in symptom scores. We hypothesized that extensive LA ablation increased the risk of stiff LA physiology. We included 1,720 patients (69.1% male, 60.0 [53.0–68.0] years old, 66.2% with paroxysmal AF) who underwent de novo AFCA and echocardiography before and 1-year after the procedure. Stiff LA physiology was defined, when the amount of the estimated pulmonary arterial pressure increase between the pre-procedural and the 1-year post-procedural follow-up echocardiography was >10 mmHg and when right ventricular systolic pressure (RVSP) was >35 mmHg at 1-year follow-up echocardiography. The failed rhythm control within 1 year was defined as recurrent AF despite using anti-arrhythmic drugs or cardioversion within a year of AFCA. We explored the incidence and risk factors for stiff LA physiology and the rhythm outcome of AFCA. Among the 1,720 patients, 64 (3.7%) had stiff LA physiology 1 year after AFCA. Stiff LA physiology was independently associated with diabetes (odds ratio [OR], 2.36 [95% CI, 1.14–4.87], p = 0.020), the ratio of the peak mitral flow velocity of the early rapid filling to the early diastolic velocity of the mitral annulus (E/Em; OR, 1.04 [95% CI, 1.00–1.10], p = 0.049), LA pulse pressure (Model 2: OR, 1.05 [95% CI, 1.00–1.11], p = 0.049), low LA voltage (OR, 0.36 [95% CI, 0.18–0.74], p = 0.005), empirical extra-pulmonary vein (PV) LA ablation (OR, 2.60 [95% CI, 1.17–5.74], p = 0.018), and radiofrequency (RF) ablation duration (Model 2: OR, 1.02 [95% CI, 1.01–1.03], p = 0.003). Although the incidence of post-AFCA stiff LA physiology was 3.7% and most of the cases were subclinical, the empirical extra-PV ablation was associated with this undesirable condition. In addition, patients who had low mean LA voltage before AFCA could be susceptible to stiff LA physiology.

Catheter ablation of atrial fibrillation benefits the patients with heart failure and preserved ejection fraction as well as those with heart failure and reduced ejection fraction

Abstract Background Although catheter ablation of atrial fibrillation (AF) has recently been shown to improve the cardiac function and even mortality in patients with heart failure (HF) and reduced ejection fraction (HFrEF), few studies have examined the outcomes of AF catheter ablation in patients with HF with preserved ejection fraction (HFpEF). Purpose To verify the impact of AF catheter ablation on the cardiac function and HF status in patients with HFpEF. Methods We studied 306 patients with HF who had a history of an HF hospitalization and/or preprocedural serum BNP levels &amp;gt;100pg/ml (age, 68.9±8.2 years old; male, 66.3%; non-paroxysmal AF, 63.1%, left atrial diameter [LAD], 42.5±6.3 mm; left ventricular ejection fraction [LVEF], 60.6±12.0%) out of 596 consecutive patients who underwent pulmonary vein isolation-based catheter ablation of AF. The patients with an LVEF ≥50% were defined as having HFpEF (n=262; age, 69.0±8.2 years old; male, 64.5%; non-paroxysmal AF, 61.8%, LAD, 42.1±5.9 mm; left LVEF, 64.0±8.2%) and the remaining patients with an LVEF &amp;lt;50% were defined as having HFrEF (n=44, age, 67.9±8.7 years old; male, 77.0%; non-paroxysmal AF, 70.5%, LAD, 44.9±8.2 mm; LVEF, 40.1±10.2%). The patients received periodic follow-ups for 12 months after the catheter ablation. The cardiac function parameters including the echocardiographic findings and HF functional status of the patients were compared between baseline and 12 months, stratified by the HF subgroup. Results AF recurred in 60 patients with HFpEF (22.9%) and in 14 with HFrEF (31.8%) during the 12 month follow-up (p=0.27), however, sinus rhythm was maintained at 12 months in most of the patients (253 patients with HFpEF [96.6%] and 42 patients with HFrEF [95.5%]) (p=0.71). Figure 1 compares the changes in the cardiac function parameters and NYHA functional class from baseline to the 12-month follow-up stratified by the HF subgroup. Both the patients with HFpEF and HFrEF had significant improvements in the serum BNP levels, chest thorax ratio, and LVEF determined by echocardiography. LA reverse remodeling as shown by a significant reduction in the LAD was observed in both HF subgroups, however, the E/E', an index of the LV diastolic function, did not significantly change in either of the subgroups. Similar to the patients with HFrEF, an improvement in the NYHA functional class was seen in those with HFpEF. Conclusions Catheter ablation of AF may benefit patients with HFpEF as well as those with HFrEF. Sinus rhythm maintenance achieved by AF catheter ablation in patients with HFpEF may lead to LA reverse remodeling and a better LV systolic function, thereby improving the NYHA functional class. It is unclear whether changes in the LV diastolic function may contribute to this favorable process. Funding Acknowledgement Type of funding source: None

Electrophysiological significance of the interatrial conduction including cavo-tricuspid isthmus during atrial fibrillation.

The interatrial conduction, including Bachmann's bundle, the posterior septal conduction, the anterior septal conduction, and the cavo-tricuspid isthmus, contributes to the maintenance mechanisms of atrial fibrillation in a 3D biatrial model. The interatrial conduction ablation including a cavo-tricuspid isthmus ablation significantly affects the wave dynamics of atrial fibrillation (AF) and facilitates the AF termination or atrial tachycardia conversion of the AF after the circumferential pulmonary vein isolation. Additional cavo-tricuspid isthmus ablation after the circumferential pulmonary vein isolation improves long-term rhythm outcome after clinical AF catheter ablation. Although it is known that atrial fibrillation (AF) is mainly a left atrial (LA) disease, the role of the right atrium (RA) and interatrial conduction (IAC), including the cavo-tricuspid isthmus (CTI), has not been clearly defined. We tested AF wave dynamics with or without IAC in computational modelling and the rhythm outcome of AF catheter ablation (AFCA) including CTI ablation in clinical cohort data. We evaluated the dominant frequency (DF) in 3D biatrial AF simulations integrated with 3D-computed tomograms obtained from 10 patients. The IAC was implemented at Bachmann's bundle, posterior septum and the CTI. After virtual circumferential PV isolation (CPVI), we disconnected IACs one by one, and observed the wave dynamics. We compared the long-term rhythm outcome after CPVI alone and additional CTI ablation in 846 patients with AFCA. LA-DF was higher than RA-DF in AF (P<0.001). After CPVI, the DF decreased significantly by additional IAC ablation (P=0.003), especially in the LA (P=0.016). The amount of DF reduction (P=0.020) and rates of AF termination (P<0.001) or AT conversion (P=0.021) were significantly higher after IAC ablations including CTI than those without. In clinical AFCA, the AF recurrence rate was significantly lower in patients with additional CTI ablation than CPVI alone during 25±20months' follow-up (hazard ratio 0.60 [0.46-0.79], P<0.001, Log rank P<0.001). IAC contributes to the maintenance mechanism of AF, and IAC including CTI ablation affects AF wave dynamics, facilitating AF termination in 3D biatrial modelling. Additional CTI ablation after CPVI improves the long-term rhythm outcome in clinical AFCA, potentially in a paroxysmal type with accompanying atrial flutter, or atrial dimension close to normal.

Atrial fibrillation history impact on catheter ablation outcome. Findings from the ESC-EHRA Atrial Fibrillation Ablation Long-Term Registry.

Atrial fibrillation (AF) promotes atrial remodeling that in turn promotes AF perpetuation. The aim of our study is to investigate the impact of AF history length on 1-year outcome of AF catheter ablation in a cohort of patients enrolled in the Atrial Fibrillation Ablation Registry. We described the real-life clinical epidemiology, therapeutic strategies, and the short- and mid-term outcomes of 1948 patients (71.9% with paroxysmal AF) undergoing AF ablation procedures, stratified according to AF history duration (<2 years or ≥2 years). The mean AF history duration was 46.2±57.4 months, 592 patients had an AF history duration <2 years (mean 10.2±5.9 months), and 1356 patients ≥2 years (mean 75.5±63.5 months) (P<0.001). Patients with AF history duration <2 years were younger; had a lower incidence of hypertension, coronary artery disease, and hypertrophic cardiomyopathy; and had a lower CHA2 DS2 -VaSc Score. At 1 year, the logrank test showed a lower incidence of AF recurrence in patients with AF history duration <2 years (28.9%) than in patients with AF history duration ≥2 years (34.0%) (P=0.037). AF history duration ≥2 years, overall ablation procedure duration, hypertension, and chronic kidney disease were all predictors of recurrences after the blanking period. In this multicenter registry, performing catheter ablation in patients with an AF history ≥2 years was associated with higher rates of AF recurrences at 1 year. Since cumulative time in AF in not necessarily equivalent to AF history, its role remains to be clarified.

Rare variants in genes encoding the cardiac sodium channel and associated compounds and their impact on outcome of catheter ablation of atrial fibrillation.

AimRare variants of genes encoding the cardiac sodium channel and associated compounds have been linked with atrial fibrillation (AF). Nevertheless, current expert consensus does not support genetic testing in AF, which is in part based on the fact that “there is no therapeutic impact derived from AF genetic test results”. However, there are no studies available supporting this recommendation. Consequently, this study analyzed the impact of rare variants affecting the cardiac sodium channel on rhythm outcome of AF catheter ablation.Methods and resultsIn 137 consecutive patients with lone AF enrolled in the Leipzig Heart Center AF ablation registry, screening for mutations in SCN5A, SCN1B – 4B, CAV3, GPD1L, SNTA1 and MOG1 was performed. We identified 3 rare non-synonymous variants in SCN5A, 5 in SCN1B, 1 in SCN4B, 1 in CAV3, 6 in GPD1L, 3 in SNTA1 and 3 in MOG1 (16%). Variant carriers were otherwise comparable with non-variant carriers. Analysis of AF recurrence rates after radiofrequency AF catheter ablation by serial 7-day Holter ECG monitoring between 3 and 12 months revealed no difference between groups, i.e. 45% in variant carriers vs. 49% in non-variant carriers.ConclusionsRare variants in genes encoding the cardiac sodium channel and associated compounds are frequently found in lone AF but were not found to impact the outcome of AF catheter ablation. This finding supports current recommendations not to screen for rare variants for the ablation outcome in AF. Nevertheless, it may at least be helpful for understanding AF mechanisms and larger studies are needed to further explore the possible association between genotype and response to AF therapies.

Association of atrial fibrillation susceptibility genes, atrial fibrillation phenotypes and response to catheter ablation: a gene-based analysis of GWAS data

BackgroundPrevious studies have suggested PITX2, KCNN3 and ZFHX3 as atrial fibrillation (AF) susceptibility genes. Single common genetic polymorphisms of those genes have been linked with AF phenotypes and rhythm outcome of AF catheter ablation although their mechanisms remain elusive. New gene-based association tests may help clarifying genotype–phenotype correlations. Therefore, we hypothesized that PITX2, KCNN3 and ZFHX3 associate with left atrial enlargement and persistent AF and subsequently with ablation outcome.Methods and resultsSamples from 660 patients with paroxysmal (n = 370) or persistent AF (n = 290) undergoing AF catheter ablation were genotyped for ~1,000,000 SNPs. Gene-based association was investigated using two different gene-based association tests (VEGAS, minSNP). Among the three candidate genes, only ZFHX3 associated with left atrial dilatation and AF recurrence after catheter ablation.ConclusionThis study suggests a contribution of ZFHX3 to AF remodeling and response to therapy. Future and larger studies are necessary to replicate and apply these findings with an emphasis on designing AF pathophysiology-based multi-locus risk scores.

Gender differences in fibrosis remodeling in patients with long-standing persistent atrial fibrillation.

The success rate of catheter ablation in atrial fibrillation (AF) is known to be lower in females than in males. However, while the exact mechanism for this phenomenon remains to be elucidated, tissue fibrosis may play an important role in this regard. It has been shown that fibrosis promotes AF and its recurrence, thereby substantially reducing the efficacy of catheter ablation in AF patients. Thus, we hypothesized that fibrosis may contribute to gender differences in the outcomes of AF catheter ablation.Here we systematically assessed pulmonary vein sleeves obtained from 166 patients with and without long-standing persistent-AF (LSP-AF) in order to identify gender-specific mechanistic differences in fibrosis remodeling of AF patients.Histological analysis revealed that the female LSP-AF group, rather than its male counterpart, had a higher degree of fibrosis when compared to the NON-AF group. Further analysis using microarray, immunohistochemistry and Western Blot displayed that gender differences in fibrosis remodeling of LSP-AF were mainly due to the inherent differential expression of fibrosis-related genes (n=32) and proteins (n=6). Especially, those related to the TGFβ/Smad3 pathway appeared to be up-regulated in the female LSP-AF group thus promoting an aggravation of fibrosis remodeling. In summary, our data suggest that the aggravation of fibrosis remodeling in women may be an important reason for the low success rate of AF catheter ablation when compared to men. Therefore, inhibiting the TGFβ/Smad3 pathway-mediated fibrosis could represent an interesting target for future therapeutic concepts to improve the success rate of AF catheter ablation in women.

Presence and extent of coronary artery disease as predictor for AF recurrences after catheter ablation: The Leipzig Heart Center AF Ablation Registry

BackgroundOcclusion of the right coronary artery (RCA) may promote atrial fibrillation (AF) by creating a right atrial substrate. However, the presence and extent of coronary artery disease (CAD) is usually not considered to tailor AF ablation strategies. This study was aimed to analyze the possible association between the presence and extent of CAD and rhythm outcomes of left-atrial AF catheter ablation. Methods1310 patients (60±10years, 67% males, 63% paroxysmal AF) from The Leipzig Heart Center AF Ablation Registry undergoing de novo AF catheter ablation were included. CAD was defined as stenosis≥50% in the left main coronary artery and ≥70% in one or several of the major coronary arteries. AF recurrences were defined as any atrial arrhythmia lasting >30s and occurring within the first week (early recurrences, ERAF) or between 3 and 12months (late recurrences, LRAF) after ablation and were assessed with serial 7-day Holter ECG. Results152 patients (11.6%) had significant CAD; 89 (59%) had one, 35 (23%) two and 28 (18%) three vessel disease; 72 (47%) patients had RCA involvement. Occurrence of AF recurrences was comparable in CAD (p=0.625 and 0.568 for ERAF and LRAF, respectively). Among patients with CAD, neither the location (RCA versus non-RCA) nor the extent of CAD (single versus multiple vessel disease) was associated with rhythm outcomes after AF catheter ablation (all p>0.05). ConclusionThe presence and extent of CAD seem not to impact on rhythm outcome of AF catheter ablation in the entire cohort.

Long-term results of single-procedure catheter ablation for atrial fibrillationin pre- and post-menopausal women.

ObjectivesTo address whether menopause affects outcome of catheter ablation (CA) for atrial fibrillation (AF) by comparing the safety and long-term outcome of a single-procedure in pre- and post-menopausal women.MethodsA total of 743 female patients who underwent a single CA procedure of drug-refractory AF were retrospectively analyzed. The differences in clinical presentation and outcomes of CA for AF between the pre-menopausal women (PreM group, 94 patients, 12.7%) and the post-menopausal women (PostM group, 649 patients, 87.3%) were assessed.ResultsThe patients in the PreM group were younger (P < 0.001) and less likely to have hypertension (P < 0.001) and diabetes (P = 0.005) than those in the PostM group. The two groups were similar with regards to the proportion of concomitant mitral valve regurgitation coronary artery disease, left atrium dimensions, and left ventricular ejection fraction. The overall rate of complications related to AF ablation was similar in both groups (P = 0.385). After 43 (16–108) months of follow-up, the success rate of ablation was 54.3% in the PreM group and 54.2% in the PostM group (P = 0.842). The overall freedom from atrial tachyarrhythmia recurrence was similar in both groups. Menopause was not found to be an independent predictive factor of the recurrence of atrial tachyarrhythmia.ConclusionsThe long-term outcomes of single-procedure CA for AF are similar in pre- and post-menopausal women. Results indicated that CA of AF appears to be as safe and effective in pre-menopausal women as in post-menopausal women.