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Background Alcohol consumption is known to increase the risk of atrial fibrillation (AF). Whether the genotypes of alcohol-metabolizing genes (alcohol dehydrogenase [ADH1B]) are associated with the risk of AF recurrence after catheter ablation remains unclear. Methods and results The ADH1B genotypes of 281 patients who received catheter ablation for AF were examined. We followed this group of patients to monitor their AF recurrence. Alcohol consumption levels of this cohort were evaluated before and after catheter ablation. There was no difference in the underlying diseases presented by the patients with different ADH1B genotypes. Regardless of the ADH1B genotypes, the amount of alcohol consumption was the only factor associated with left atrial dilatation. The ADH1B*2 alleles (hazard ratio: ADH1B*1/*2 vs *1/*1: 2.64; ADH1B*2/*2 vs *1/*1: 1.80, P = 0.02) and the levels of alcohol consumption were independently associated with AF recurrence in the patients with paroxysmal AF after catheter ablation. ADH1B polymorphisms were not associated with AF recurrence in the patients with nonparoxysmal AF. We also found that the association of increased AF recurrence with alcohol consumption and the ADH1B genotypes cannot be explained by mechanisms of systemic inflammation. Conclusions ADH1B*2/*2 genotype and amount of alcohol consumption increase the risk of AF recurrence after catheter ablation. [ABSTRACT FROM AUTHOR]

Background Noncompliant patients might be at risk of thromboembolism because of the short half-life and rapid offset of dabigatran etexilate. The assessment and management of dabigatran noncompliance should be optimized. Methods and Results A total of 150 nonvalvular atrial fibrillation patients receiving dabigatran were prospectively enrolled and followed for drug compliance and persistence. Noncompliance was identified by questionnaires and interviews. The hemoclot thrombin inhibitor (HTI) assay was used for monitoring the plasma dabigatran levels. Sixteen patients were noncompliant (10.7%). None of the clinical characteristics were significantly relevant to noncompliance after multivariate analysis. The dabigatran plasma level based on HTI was the only independent predictor of noncompliance (odds ratio: 0.97 per ng/mL, P = 0.003). The prothrombin time (PT), international normalized ratio of PT (INR [PT]), and activated partial thromboplastin time did not differ between compliant and noncompliant patients. During the follow-up, the persistent prescription of dabigatran was noted in 75% of noncompliant patients without improvement in compliance. The drug discontinuation rate was higher in the noncompliant than compliant patients (6.7% vs. 25%, P = 0.035). None of the patients in either group received warfarin after discontinuing dabigatran. Conclusions The assessment and management of dabigatran noncompliance is generally ignored in clinical practice. The measurement of dabigatran plasma levels by HTI could be a reliable and simple method to identify noncompliant patients. [ABSTRACT FROM AUTHOR]

Background: The anatomical differences with age may raise difficulty in determining the proper positioning of the transseptal puncture site in the therapeutic left heart catheterization. This study investigated whether age affects the fluoroscopy-guided transseptal puncture in the catheter ablation of atrial fibrillation. Methods and Results: Fifty patients (52 ± 12 years, 35 men) who underwent ablation for paroxysmal/persistent atrial fibrillation were included. The patients were divided into two groups according to their age (cut-point 50 y/o): young group (n = 20) and old group (n = 30). In the 30° right anterior oblique view (RAO), the width between the transseptal puncture site and coronary sinus ostium (H N-CSO) was longer in old-age group (14.4 ± 9.4 vs 10.9 ± 10.4 mm, P = 0.034). In the 60° left anterior oblique view (LAO) view, the angle of the direction of the transseptal needle (N-angle) was less in the old-age group (56.0 ± 10.0° vs 58.4 ± 9.8°, P = 0.041). The ratio of the transseptal puncture site-coronary sinus ostium (CSO) distance over the distance between the superior vena cava-right atrial junction and CSO (VN-CSO/VJ-CSO) was significantly higher in the old-age group (0.73 ± 0.12 vs 0.63 ± 0.2, P = 0.009). Conclusion: The transseptal puncture site in the RAO view moved higher and more posterior and the transseptal puncture angle in the LAO view decreased with age. These findings highlight the influence of age on the atrial anatomy and transseptal puncture site. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) prevalence increases with age. Aging affects the substrate properties of the left atrium (LA) and the outcomes of catheter ablation for treating AF. We investigated the AF trigger distribution and catheter ablation outcomes in patients of different ages with AF. Methods: 1585 patients with AF (1181 paroxysmal and 404 non‐ paroxysmal AF) who had undergone catheter ablation were enrolled. The patients were divided into young (20–40 year‐old, n = 175), middle‐aged (41–64 year‐old, n = 1134), and old (≥ 65 year‐old, n = 276) groups. Electrophysiological characteristics and AF trigger sites were recorded. Result: The incidence of AF with only non‐pulmonary vein (non‐PV) foci was higher in the young group than in the other groups (8.6% vs. 3.6% vs. 3.3%, p < 0.01). Non‐PV foci were more commonly located in the superior vena cava (SVC) in the young group than in the other groups (13.1% vs. 7.8% vs. 6.5%, p = 0.03). The left atrium (LA) mean voltage was higher and the incidence of very late recurrence after AF ablation was lower in the young group than in the other groups. However, the final AF recurrence rate after multiple procedures and complication rates were similar among all the groups at a mean follow‐up of 5.6 years. Conclusion: The young patients with AF had a higher incidence of only non‐PV foci, mostly located in SVC, than the middle‐aged and old patients. Our study highlights the importance of identifying the non‐PV foci in catheter ablation of young patients with AF. [ABSTRACT FROM AUTHOR]

Introduction: The efficacy of stereotactic body radiation therapy (SBRT) as an alternative treatment for recurrent ventricular tachycardia (VT) is still unclear. This study aimed to report the outcome of SBRT in VT patients with nonischemic cardiomyopathy (NICM). Methods: The determination of the target substrate for radiation was based on the combination of CMR results and electroanatomical mapping merged with the real‐time CT scan image. Radiation therapy was performed by Flattening‐filter‐free (Truebeam) system, and afterward, patients were followed up for 13.5 ± 2.8 months. We analyzed the outcome of death, incidence of recurrent VT, ICD shocks, anti‐tachycardia pacing (ATP) sequences, and possible irradiation side‐effects. Results: A total of three cases of NICM patients with anteroseptal scar detected by CMR. SBRT was successfully performed in all patients. During the follow‐up, we found that VT recurrences occurred in all patients. In one patient, it happened during a 6‐week blanking period, while the others happened afterward. Re‐hospitalization due to VT only appeared in one patient. Through ICD interrogation, we found that all patients have reduced VT burden and ATP therapies. All of the patients died during the follow‐up period. Radiotherapy‐related adverse events did not occur in all patients. Conclusions: SBRT therapy reduces the number of VT burden and ATP sequence therapy in NICM patients with VT, which had a failed previous catheter ablation. However, the efficacy and safety aspects, especially in NICM cases, remained unclear. [ABSTRACT FROM AUTHOR]

Background: Premature ventricular contractions (PVCs) induced by subtle cardiac dysfunction are missed by echocardiography. We evaluated acoustic cardiography for detection of early electromechanical dysfunction in patients with idiopathic PVCs and normal left ventricular ejection fraction (LVEF), and investigated the impact of radiofrequency ablation (RFA) in reversing this adverse effect. Methods: Eighty‐six patients with PVCs and 33 normal controls having normal LVEF were studied. Fifty PVC patients were in the ablation group and 36 in the nonablation group. %Electromechanical activation time (%EMAT), %left ventricular systolic time (%LVST), third (S3) and fourth heart sound (S4), and systolic dysfunction index (SDI) during sinus rhythm (SR) were measured by acoustic cardiography (Audicor, Inovise Medical, Inc., Beaverton, OR, USA) pre‐ and postablation. In 28 patients, acoustic parameters were compared during SR without PVCs, and SR with single PVC, ≥ 2 PVCs, or ventricular tachycardia over 10‐second Audicor recording in a single patient at different times. Twenty‐four‐hour acoustic cardiographic and acoustic cardiographic Holter recording were used to assess the impact of PVC burden on electromechanical function in 41 patients. Results: %EMAT, S3, S4, and SDI showed significant worsening in the PVC versus control group. %EMAT and SDI were worsened with increasing PVC number in a 10‐second strip. %EMAT showed significant linear increment with increasing PVC burden. There was a significant improvement in %EMAT, %LVST, S3, S4, and SDI postablation in patients with PVCs. Conclusion: Acoustic cardiography can detect PVC‐induced minor electromechanical dysfunction in patients with normal LVEF. RFA can reverse this adverse effect. [ABSTRACT FROM AUTHOR]

Introduction: Adjunctive driver‐guided ablation in addition to pulmonary vein isolation has been proposed as a strategy to improve procedural success and outcomes for various populations with atrial fibrillation (AF). First, this study aimed to evaluate the different mapping techniques for driver/rotor identification and second to evaluate the benefits of driver/rotor‐guided ablation in patients with paroxysmal and persistent AF (PerAF). Methods: We searched the electronic database in PubMed using the keywords "atrial fibrillation," "rotor," "rotational driver," "atrial fibrillation source," and "drivers" for both randomized controlled trials and observational controlled trials. Clinical studies reporting efficacy or safety outcomes of driver‐guided ablation for paroxysmal AF or (PerAF) were identified. We performed subgroup analyses comparing different driver mapping methods in patients with PerAF. The odds ratios (ORs) with random effects were analyzed. Results: Out of 175 published articles, seven met the inclusion criteria, of which two were randomized controlled trials, one was quasiexperimental study, and four observational studies (three case‐controlled studies and one cross‐sectional study). Overall, adjunctive driver‐guided ablation was associated with higher rates of acute AF termination (OR: 4.62, 95% confidence interval [CI]: 2.12‐10.08; P < 0.001), lower recurrence of any atrial arrhythmia (OR: 0.44, 95% CI: 0.30‐0.065; P < 0.001), and comparable complication incidence. Conclusions: Adjunctive driver‐guided catheter ablation suggested an increased freedom from AF/AT relative to conventional strategies, irrespective of the mapping techniques. Furthermore, phase mapping appears to be superior to electrogram‐based driver mapping in PerAF ablation. [ABSTRACT FROM AUTHOR]

Backgrounds Substrate property is related to the genesis and maintenance of atrial fibrillation (AF). The aim of the study was to investigate the impact of substrate property on the electrocardiogram (ECG) in patients with AF originating from the superior vena cava (SVC). Methods and Results Seventy-six patients with AF originating from SVC who underwent catheter ablation were included from 2004 to 2013. Of these patients, 16 had a presentation of atrial flutter (AFL)-pattern ECG during AF (group 1), and 60 patients did not (group 2). There was no significant difference in clinical characteristics between the groups. The percentage of low voltage zone (LVZ) in SVC below the level of pulmonary artery in group 1 was significantly larger than that in group 2. The polarities of the flutter wave in 12-lead ECG were compared with another 26 subjects with reverse typical AFL. The ECG morphology was characterized by negative or biphasic P waves in lead V1 in most of the patients in group 1 (62.5%), which was analogous to that in reverse typical AFL. The negative polarity of flutter waves in aVL might distinguish SVC AF with an AFL-pattern from reverse typical AFL. Conclusion The ECG characteristics of AF originating from SVC can mimic atypical AFL. LVZ in the SVC may be associated with the presentation of AFL-pattern ECG. [ABSTRACT FROM AUTHOR]

Background: The different settings of the automatic algorithm in the Carto system (Carto XP, Biosense Webster, Diamond Bar, CA, USA) used for detecting complex fractionated electrograms (CFEs) during atrial fibrillation (AF) may influence the identification of the fragmented electrograms. Objectives: We aimed to evaluate the impact of the different parameters on the detection of CFEs and the efficacy of the substrate modification after pulmonary vein isolation (PVI). Methods: A total of 1,159 electrograms were analyzed from 11 consecutive patients (age = 56 ± 12 years). The effect of the different algorithm factors, such as the high-voltage thresholds (0.12, 0.25, 0.5, 20 mV), detection algorithms (average complex interval [ACI] vs interval confidence level), and recording duration (2.5 seconds vs 5 seconds), on the disparities of the CFEs was investigated. Results: The proportion of the different grades of CFEs depended on the detection algorithm and recording duration. The high-voltage threshold would not affect the consistency of the CFEs irrespective of the different settings of the detection algorithm or recording duration. High-grade CFEs were most consistent with an ACI algorithm and recording duration of 5 seconds (Cronbach's alpha = 0.952). Ablation consisting of a PVI and high-grade CFE sites converted AF directly to sinus rhythm in eight of 11 patients or into atrial tachycardia in one of 11. Conclusions: The distribution and consistency of the CFE detection depended on the detection algorithm and recording duration, but not on the high-voltage threshold. Under the ACI algorithm and a recording duration of 5 seconds, high-grade CFE sites remained highest consistency. (PACE 2012; 35:980-989) [ABSTRACT FROM AUTHOR]

To evaluate contemporary trends of clinical characteristics, etiologies, and underlying diseases, and their relationship between different bradyarrhythmias in patients undergoing temporary pacemakers (TPMs). This study included 509 patients (77 ± 11 year, 74% males) with symptomatic bradyarrhythmias requiring TPMs between 2002 and 2008. Demographics, electrocardiographic indications, etiologies, underlying diseases, and the outcome of permanent pacemaker (PPM) implants within 30 days were analyzed. Atrioventricular conduction dysfunction (AVCD) (64.0%) dominated in all bradyarrhythmias, with idiopathic degeneration (61%) as its major etiology. Antiarrhythmic drug (38%) was the leading cause in sinoatrial node dysfunction (SAND). There was an increasing trend in AVCD, while a decreasing trend in SAND. Regarding etiologies for TPM, an increasing trend was found in idiopathic degeneration, whereas a decreasing trend in acute coronary syndrome (ACS). Idiopathic degeneration had an odds ratio (OR) of 1.9 for AVCD (P = 0.001), whereas electrolyte/acid-base disturbances (OR = 3.7, P = 0.001), β-blockers (OR = 2.4, P = 0.002), and chronic renal disease (OR = 1.9, P = 0.01) were associated with SAND. Patients with intrinsic etiologies for TPM had a high incidence of PPM implantation within 30 days than those with extrinsic causes (67.5% vs 3.8%, P < 0.0001) Increasing trends in patients requiring TPMs were observed in the elderly patients and those with AVCD and idiopathic degeneration, while decreasing trends were observed in those with SAND and ACS. Idiopathic degeneration was associated with AVCD, whereas extrinsic etiologies were related to SAND. Patients with intrinsic etiologies had a higher incidence of PPM implantation than those with extrinsic factors for TPM. (PACE 2010; 33:1475-1484) [ABSTRACT FROM AUTHOR]

We report a case with dextrocardia, corrected transposition of the great arteries. He also had an atrial septum defect (ASD) with patch repair. Activation map showed a centrifugal activation from a focal origin on the systemic lower left atrial ASD patch. Ablation of the origin can terminate the atrial tachycardia. (PACE 2012; 35:e306-e308) [ABSTRACT FROM AUTHOR]

We report a case of focal atrial tachycardia (AT) originating from prior superior vena cava isolation line. The P-wave morphology in lead aVL during the AT differed from that during sinus rhythm although their foci were in close proximity to each other. We discuss the mechanism based on the activation maps of the right atrium. (PACE 2010; 33:e100-e101) [ABSTRACT FROM AUTHOR]