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Coffee and tea are amongst the most consumed beverages worldwide, and are the main source of caffeine in adults. In this review we present findings on the effects of habitual coffee and tea consumption on cardiovascular disease (CVD) prevention. Mild-moderate coffee/ caffeine consumption, at 2-3 cups/day, is associated with beneficial effects on metabolic syndrome, including hypertension and diabetes mellitus, although may elevate lipid levels. Furthermore, coffee consumption reduces the risk of coronary heart disease, heart failure, arrhythmia, stroke, CVD and all cause mortality. Higher tea consumption, in particular green tea, confers similar cardiovascular benefits to coffee with 3 cups/day associated with improved survival in population based studies.

Background The success of pulmonary vein isolation (PVI) is reduced in persistent AF (PsAF) compared to paroxysmal AF. Adjunctive ablation strategies have failed to show consistent incremental benefit over PVI alone in randomized studies. The left atrial posterior wall is a potential source of non-PV triggers and atrial substrate which may promote the initiation and maintenance of PsAF. Adding posterior wall isolation (PWI) to PVI had shown conflicting outcomes, with earlier studies confounded by methodological limitations. Objectives To determine whether combining PWI with PVI significantly improves freedom from AF recurrence, compared to PVI alone, in patients with PsAF. Methods This is a multi-center, prospective, international randomized clinical trial. 338 patients with symptomatic PsAF refractory to anti-arrhythmic therapy (AAD) will be randomized to either PVI alone or PVI with PWI in a 1:1 ratio. PVI involves wide antral circumferential pulmonary vein (PV) isolation, utilizing contact force sensing ablation catheters. PWI involves the creation of a floor line connecting the inferior aspect of the PVs, and a roof line connecting the superior aspect of the PVs. Follow up is for a minimum of 12 months with rhythm monitoring via implantable cardiac device and/or loop monitor, or frequent intermittent monitoring with an ECG device. The primary outcome is freedom from any documented atrial arrhythmia of > 30 seconds off AAD at 12 months, after a single ablation procedure. Conclusions This randomized study aims to determine the success and safety of adjunctive PWI to PVI in patients with persistent AF.

Objectives This study sought to describe expected changes in a mirror-image prone electrocardiogram (ECG) compared with normal supine, including a range of cardiac conditions. Background Unwell COVID-19 patients are at risk of cardiac complications. Prone ventilation is recommended but poses practical challenges to acquisition of a 12-lead ECG. The effects of prone positioning on the ECG remain unknown. Methods 100 patients each underwent 3 ECGs: standard supine front (SF); prone position with precordial leads attached to front (PF); and prone with precordial leads attached to back in a mirror image to front (PB). Results Prone positioning was associated with QTc prolongation (PF 437 ± 32 ms vs. SF 432 ± 31 ms; p, Central Illustration

BACKGROUND: Binge drinking is a common atrial fibrillation (AF) trigger, however the mechanisms are poorly understood. OBJECTIVE: To investigate the effects of alcohol intoxication and hangover with rhythm monitoring and cardiac MRI. METHODS: Patients underwent serial cardiac MRI pre- and post-binge with continuous Holter monitoring. Time periods analyzed: baseline (24 h pre-binge), consumption, hangover (0- 24 h post-consumption) and post-hangover (24-48 h post-consumption). RESULTS: 50 patients (age 49 ± 15 years, 40% paroxysmal AF) completed the study (intake 8.4 ± 3.1 standard drinks). Mean heart rate increased from 72 ± 10 to 80 ± 13 beats per minute (bpm) during consumption (p

AIMS: The impact of atrial fibrillation (AF) ablation in early heart failure with preserved ejection fraction (HFpEF) is unknown. Our aim was to determine the impact of AF ablation on symptoms and exercise haemodynamic parameters of early HFpEF. METHODS AND RESULTS: Symptomatic AF patients referred for index AF ablation with ejection fraction ≥50% underwent baseline quality of life questionnaires, echocardiography, cardiac magnetic resonance imaging, exercise right heart catheterisation (exRHC), and brain natriuretic peptide (BNP) testing. HFpEF was defined by resting pulmonary capillary wedge pressure (PCWP) ≥15 mmHg or peak exercise PCWP ≥25 mmHg. Patients with HFpEF were offered AF ablation and follow-up exRHC ≥6 months post-ablation. Of 54 patients undergoing baseline evaluation, 35 (65%) had HFpEF identified by exRHC. HFpEF patients were older (64 ± 10 vs. 54 ± 13 years, P

Aims There are conflicting data as to the impact of procedural volume on outcomes with specific reference to the incidence of major complications after catheter ablation for atrial fibrillation. Questions regarding minimum volume requirements and whether these should be per centre or per operator remain unclear. Studies have reported divergent results. We performed a systematic review and meta-analysis of studies reporting the relationship between either operator or hospital atrial fibrillation (AF) ablation volumes and incidence of complications. Methods and results Databases were searched for studies describing the relationship between operator or hospital AF ablation volumes and incidence of complications which were published prior to 12 June 2020. Of 1593 articles identified, 14 (315 120 patients) were included in the meta-analysis. Almost two-thirds of the procedures were performed in low-volume centres. Both hospital volume of ≥50 and ≥100 procedures/year were associated with a significantly lower incidence of complications compared to Conclusion There is an inverse relationship between both hospital and proceduralist AF ablation volume and the incidence of complications. Implementation of minimum hospital and operator AF ablation volume standards should be considered in the context of a broader strategy to identify AF ablation Centers of Excellence.

Objectives This study sought to determine the long-term outcomes of restoring sinus rhythm with catheter ablation (CA). Background The CAMERA-MRI (Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Heart Failure—An MRI-Guided Multicenter Randomized Controlled Trial) study demonstrated that restoration of sinus rhythm with CA significantly improved left ventricular ejection fraction (LVEF) compared with medical rate control (MRC) at 6 months in persistent atrial fibrillation and otherwise unexplained systolic heart failure. However, the long-term outcomes have not been reported. Methods Patients enrolled in the CAMERA-MRI study were followed for 4 years with echocardiogram and cardiac magnetic resonance. CA involved pulmonary vein isolation and posterior left atrial wall isolation in 94%. Patients crossed over to CA after 6-month study duration. Arrhythmia burden was determined with implanted cardiac monitors or cardiac devices. Results Sixty-six patients (age 62 ± 10 years, atrial fibrillation duration of 22 ± 16 months, and LVEF 33 ± 9%) were randomized 1:1 to CA versus MRC. Eighteen of 33 patients crossed over from MRC group to CA group. At 4.0 ± 0.9 years, atrial fibrillation recurred in 27 patients (57%) in the CA group with a mean burden of 10.6 ± 21.2% after 1.4 ± 0.6 procedures. There was an absolute increase in LVEF with CA of 16.4 ± 13.3% compared with 8.6 ± 7.6% in MRC (p = 0.001). In the CA group, the absence of ventricular late gadolinium enhancement was associated with a greater improvement in absolute LVEF (19 ± 13% vs. 10 ± 11% in the late gadolinium enhancement–positive group; p = 0.04) and LVEF normalization in 19 patients (58%) versus 4 patients (18%) in the late gadolinium enhancement–positive group (p = 0.008) at 4.0 ± 0.9 years follow-up. Conclusions CA is superior to MRC in improving LVEF in the long term in patients with atrial fibrillation and systolic heart failure. The greatest recovery in systolic function was demonstrated in the absence of ventricular fibrosis on cardiac magnetic resonance.

This study evaluated if modifying electrocardiographic (ECG) precordial leads to a higher intercostal position improved the accuracy of outflow tract ventricular arrhythmia (OTVA) localization.Precordial ECG prediction algorithms that use a standard lead configuration localize OTVA with variable accuracy.Patients who underwent OTVA ablation were prospectively enrolled to have a standard and modified (high) precordial ECG. R- and S-wave amplitudes and intervals were measured to develop an algorithm that differentiated the right ventricular outflow tract (RVOT) and the left ventricular outflow tract (LVOT) with high accuracy-the modified lead R-wave deflection interval (RWDI). This interval was defined from the earliest QRS onset (using all modified leads) to the lead with longest R-wave deflection. The RWDI was compared with all other ECG algorithms.A total of 50 patients (38 women; mean age 51 ± 17 years) had successful catheter ablation for OTVA (RVOT 60%, LVOT 40%). The modified lead RWDI was significantly shorter in the RVOT group (18.5 ms, interquartile range 25th to 75th percentile [IQRThe modified lead RWDI is a simple, easily interpretable algorithm that can potentially differentiate a right- or left-sided origin of OTVA with high accuracy.

Background Paroxysmal atrial fibrillation (PAF) is associated with cardioembolic risk, however events may occur during sinus rhythm (SR). 4D-flow cardiac magnetic resonance (CMR) imaging allows visualisation of left atrial blood flow, to determine the residence time distribution (RTD), an assessment of atrial transit time. Objective To determine if atrial transit time is prolonged in PAF patients during SR, consistent with underlying atrial stasis. Method 91 participants with PAF and 18 healthy volunteers underwent 4D flow analysis in SR. Velocity fields were produced RTDs, calculated by seeding virtual ‘particles’ at the right upper pulmonary vein and counting them exiting the mitral valve. An exponential decay curve quantified residence time of particles in the left atrium, and atrial stasis was expressed as the derived constant (RTDTC) based on heartbeats. The RTDTC was evaluated within the PAF group, and compared to healthy volunteers. Results Patients with PAF (n = 91) had higher RTDTC compared with gender-matched controls (n = 18) consistent with greater atrial stasis (1.68 ± 0.46 beats vs 1.51 ± 0.20 beats; p = .005). PAF patients with greater thromboembolic risk had greater atrial stasis (median RTDTC of 1.72 beats in CHA₂DS₂-VASc≥2 vs 1.52 beats in CHA₂DS₂-VASc Conclusions Atrial stasis quantified by 4D flow is greater in PAF, correlating with higher CHA₂DS₂-VASc scores. Female gender and systolic dysfunction are associated with atrial stasis. RTD offers an insight into atrial flow that may be developed to provide a personalised assessment of thromboembolic risk.

Background Clinical studies have reported that epicardial adipose tissue (EpAT) accumulation associates with the progression of atrial fibrillation (AF) pathology and adversely affects AF management. The role of local cardiac EpAT deposition in disease progression is unclear, and the electrophysiological, cellular, and molecular mechanisms involved remain poorly defined. Objectives The purpose of this study was to identify the underlying mechanisms by which EpAT influences the atrial substrate for AF. Methods Patients without AF undergoing coronary artery bypass surgery were recruited. Computed tomography and high-density epicardial electrophysiological mapping of the anterior right atrium were utilized to quantify EpAT volumes and to assess association with the electrophysiological substrate in situ. Excised right atrial appendages were analyzed histologically to characterize EpAT infiltration, fibrosis, and gap junction localization. Co-culture experiments were used to evaluate the paracrine effects of EpAT on cardiomyocyte electrophysiology. Proteomic analyses were applied to identify molecular mediators of cellular electrophysiological disturbance. Results Higher local EpAT volume clinically correlated with slowed conduction, greater electrogram fractionation, increased fibrosis, and lateralization of cardiomyocyte connexin-40. In addition, atrial conduction heterogeneity was increased with more extensive myocardial EpAT infiltration. Cardiomyocyte culture studies using multielectrode arrays showed that cardiac adipose tissue-secreted factors slowed conduction velocity and contained proteins with capacity to disrupt intermyocyte electromechanical integrity. Conclusions These findings indicate that atrial pathophysiology is critically dependent on local EpAT accumulation and infiltration. In addition to myocardial architecture disruption, this effect can be attributed to an EpAT-cardiomyocyte paracrine axis. The focal adhesion group proteins are identified as new disease candidates potentially contributing to arrhythmogenic atrial substrate.

Background Multipolar catheters provide high-density mapping which may reduce the procedural duration and improve the success of catheter ablation (CA) for focal arrhythmias. The high-density grid (HDG) catheter is a 16 electrode mapping catheter with bipole recordings at orthogonal splines. The aim of this study is to compare the clinical and procedural features from a cohort who underwent CA for focal arrhythmias using multipolar mapping (MPM) with age and case-matched cohort using point-by-point (PbyP) mapping. Methods Consecutive patients undergoing CA for focal arrhythmias between October 2018 and January 2020 guided by MPM were compared with PbyP mapping with the ablation catheter over a similar period. Demographics, procedural features, and outcomes were compared. Results A total of 54 patients (27 in MPM vs. 27 in PbyP mapping) underwent CA for 68 focal arrhythmias (26 atrial and 42 ventricular). In the MPM group, the electrogram at the successful site was significantly earlier (39 ± 11 ms) than in the PbyP group (33 ± 7 ms; p = .02). In the MPM group, the mapping time (35 ± 24 vs. 53 ± 31 min in PbyP; p = .03) and procedural duration (126 ± 42 vs. 153 ± 39 min in PbyP; p = .02) were significantly shorter. There was no significant difference in radiofrequency and fluoroscopy times, acute procedural success, and arrhythmia recurrence. Conclusion MPM with the HDG catheter for focal tachycardias identified earlier activation times and was associated with shorter mapping and procedure duration with equivalent success to PbyP mapping.

The COVID-19 pandemic poses a significant stress on health resources in Australia. The Heart Rhythm Council of the Cardiac Society of Australia and New Zealand aims to provide a framework for efficient resource utilisation balanced with competing risks when appropriately treating patients with cardiac arrhythmias. This document provides practical recommendations for the electrophysiology (EP) and cardiac implantable electronic devices (CIED) services in Australia. The document will be updated regularly as new evidence and knowledge is gained with time.

Background Female gender is associated with an increased recurrence of atrial fibrillation (AF) after catheter ablation (CA). Although AF is more common in men, women constitute a significant proportion with persistent atrial fibrillation (PsAF). Objective The purpose of this study was to determine whether multiple ablation procedures improves arrhythmia outcomes in females with PsAF compared to men. Methods We performed a multicenter observational study to determine long-term arrhythmia outcomes in patients undergoing >1 CA for PsAF. CA involved pulmonary vein (PV) isolation with additional ablation including linear, posterior wall isolation, electrogram-guided, or a combination of these. Results A total of 281 patients had >1 ablation procedure for PsAF and were included in this analysis (mean age 58.7 ± 9.3 years; 86 [30.6%] female; left atrial [LA] area 27.0 ± 5.3 cm2; PsAF duration 1.7 ± 1.7 years). At mean follow-up of 45.5 ± 31.8 months, freedom from recurrent AF was present in 148 patients(52.7%) after 2.2 ± 0.5 procedures. After multivariate analysis, female gender (hazard ratio [HR] 2.10; P Conclusion Female gender was independently and strongly associated with arrhythmia recurrence in patients undergoing multiple procedures for PsAF. PV reconnection was less likely, and fewer reconnected PVs occurred in women. Further studies are required to better understand the mechanisms responsible for AF in females to assist in closing the gender gap in the success of CA.

Background The diagnostic yield of post-mortem interrogation of cardiac implantable electronic devices (CIEDs) including pacemakers, defibrillators and implantable loop recorders has not been well described. Methods We reviewed all post-mortem CIED interrogations performed by our statewide Institute of Forensic Medicine between 2005–2020 for investigation of sudden or unexplained death. Results 260 patients (68.8% male, median age 72.8 years [IQR 62.7–82.2]) underwent post-mortem CIED interrogation (202 pacemakers, 56 defibrillators and 2 loop recorders). CIEDs were implanted for a median of 2.0 [IQR 0.75–5] years, with 19 devices requiring replacement (and 5 end of life). Post-mortem interrogation was successful in 256 (98.5%) cases. Potential CIED malfunction was identified in 21 (8.1%) cases: untreated ventricular arrhythmias (n=13), lead failures (n=3) and battery depletion (n=5). CIED interrogation directly informed cause of death in 130 (50.0%) cases, with fatal ventricular arrhythmias identified in 121 patients (46.5%). In retrospect, 72 (27.7%) patients had abnormalities recorded by their device in the 30 days preceding death: non-sustained ventricular tachycardia (n=26), rapid atrial fibrillation (n=17), longevity concerns (n=22), intrathoracic impedance alarms (n=3), lead issues (n=3) or therapy delivered (n=1). In 6 cases where the patient was found deceased after a prolonged time, CIED interrogation accurately determined time of death. In one case, CIED interrogation was the primary method of patient identification. Conclusion Post-mortem CIED interrogation frequently contributes important information regarding critical device malfunction, pre-mortem abnormalities, cause and time of death or patient identity. Device interrogation should be considered for select patients with CIEDs undergoing autopsy. Funding Acknowledgement Type of funding sources: None.

Objectives This study sought to determine the impact of rate and direction on left atrial (LA) substrate. Background The extent to which substrate mapped in sinus rhythm varies according to cycle length and direction of wave front propagation is unknown. Methods A total of 73 consecutive patients with atrial fibrillation (AF) underwent electroanatomic LA mapping before pulmonary vein isolation using multipolar catheter during distal coronary sinus (CS) pacing at 600 ms and 300 ms. Additional maps were created during left superior pulmonary vein pacing at 300 ms. Bipolar voltage, conduction velocity (CV), and complex signals were determined. Results Mean age was 61 ± 9 years, 67% were men, and 53% had persistent AF. Global mean voltage was lower with CS pacing at 300 ms compared with 600 ms (1.56 ± 0.47 mV vs. 1.74 ± 0.48 mV; p Conclusions In patients with AF, variation in cycle length and direction of wave front activation produce both generalized and regional changes in voltage, CV, and complex fractionation, resulting in significant changes in substrate maps. This study highlights the potential limitations of static low-voltage maps to identify the AF ablation target zone.

Caffeine is the world's most popular 'drug', with tea and coffee a ubiquitous part of daily life. As a psychoactive stimulant, there are potential concerns regarding adverse cardiovascular squeal. Cardiovascular conditions, encompassing hypertension, coronary artery disease, rhythm disorders and heart failure affect billions of patients worldwide. We aim to provide a patient-centered comprehensive review of the cardiovascular effects of caffeinated beverages as they pertain to various common cardiovascular conditions. We conclude that intake of tea and coffee, particularly in moderate doses, does not appear to be harmful and may even be beneficial in a range of cardiovascular conditions, including coronary artery disease, heart failure and arrhythmias.

Objectives: This study sought to determine the long-term right atrial (RA) electrical and structural changes in a subgroup from the CAMERA-MRI (Catheter Ablation Versus Medical Rate Control...

Atrial fibrillation and heart failure (HF) frequently coexist and are associated with a significant increase in morbidity and mortality. Despite the shared common risk factors atrial fibrillation and HF subtypes exacerbate each other. This review provides an overview of the pathophysiologic relationship between atrial fibrillation and the two most common types of heart failure syndromes: HF with reduced ejection fraction and HF with preserved ejection fraction.

Orthotropic heart transplantation remains the most effective therapy for patients with end-stage heart failure, with a median survival of ≈13 years. Yet, a number of complications are observed after orthotropic heart transplantation, including atrial and ventricular arrhythmias. Several factors contribute to arrhythmias, such as autonomic denervation, effect of the surgical technique, acute and chronic rejection, and transplant vasculopathy among others. To minimize risk of future arrhythmias, the bicaval technique and minimizing ischemic time are current surgical standards. Sinus node dysfunction is the most common indication for early (within 30 days) pacemaker implantation, whereas atrioventricular block incidence increases as time from transplant increases. Atrial fibrillation can occur in the first few weeks following transplantation but is uncommon in the long term unless secondary to a precipitant such as acute rejection. The most common atrial arrhythmias are atrial flutters, which are mainly typical, but atypical circuits can be observed such as those that involve the remnant donor atrium in regions immediately adjacent to the atrioatrial anastomosis suture line. Choosing the appropriate pharmacological therapy requires careful consideration due to the potential interaction with immunosuppressive agents. Despite historical concerns, adenosine is effective and safe at reduced doses if administered under cardiac monitoring. Catheter ablation has emerged as an effective treatment strategy for symptomatic supraventricular tachycardias, including ablation of atypical flutter circuits. Cardiac allograft vasculopathy is an important risk factor for sudden cardiac death, yet the role of prophylactic implantable cardioverter-defibrillator implant for sudden death prevention is unclear. Current indications for implantable cardioverter-defibrillator implantation are as in the nontransplant population. A number of questions for future research are posed.

BACKGROUND: Catheter ablation is highly effective for atrioventricular nodal re-entrant tachycardia (AVNRT). Generally junctional rhythm (JR) is an accepted requirement for successful ablation however there is a lack of detailed prospective studies to determine the characteristics of JR and the impact on slow pathway conduction. METHODS: Multicentre prospective observational study evaluating the impact of individual radiofrequency (RF) applications in typical AVNRT (slow/fast). Characteristics of JR during ablation were documented and detailed testing was performed after every RF application to determine outcome. Procedural success was defined as ≤1 AV nodal echo. RESULTS: Sixty-seven patients were included (mean age 53 ± 18years, 57% female and a history of SVT 2.9 ± 4.7 years). RF (50w, 60°) ablation for AVNRT was applied in 301 locations with JR in 178 (59%). Successful slow pathway modification was achieved in 66 (99%) patients with slow pathway block in 30 (46%). Success was associated with JR in all patients. Success was achieved in six patients with RF

Background: Endocardial-epicardial dissociation and focal breakthroughs in humans with atrial fibrillation (AF) have been recently demonstrated using activation mapping of short 10-second AF segments. In the current study, we used simultaneous endo-epi phase mapping to characterize endo-epi activation patterns on long segments of human persistent AF. Methods: Simultaneous intraoperative mapping of endo- and epicardial lateral right atrium wall was performed in patients with persistent AF using 2 high-density grid catheters (16 electrodes, 3 mm spacing). Filtered unipolar and bipolar electrograms of continuous 2-minute AF recordings and electrodes locations were exported for phase analyses. We defined endocardial-epicardial dissociation as phase difference of ≥20 ms between paired endo-epi electrodes. Wavefronts were classified as rotations, single wavefronts, focal waves, or disorganized activity as per standard criteria. Endo-Epi wavefront patterns were simultaneously compared on dynamic phase maps. Complex fractionated electrograms were defined as bipolar electrograms with ≥5 directional changes occupying at least 70% of sample duration. Results: Fourteen patients with persistent AF undergoing cardiac surgery were included. Endocardial-epicardial dissociation was seen in 50.3% of phase maps with significant temporal heterogeneity. Disorganized activity (Endo: 41.3% versus Epi: 46.8%, P =0.0194) and single wavefronts (Endo: 31.3% versus Epi: 28.1%, P =0.129) were the dominant patterns. Transient rotations (Endo: 22% versus Epi: 19.2%, P =0.169; mean duration: 590±140 ms) and nonsustained focal waves (Endo: 1.2% versus Epi: 1.6%, P =0.669) were also observed. Apparent transmural migration of rotational activations (n=6) from the epi- to the endocardium was seen in 2 patients. Electrogram fractionation was significantly higher in the epicardium than endocardium (61.2% versus 51.6%, P Conclusions: Simultaneous endo-epi phase mapping of prolonged human persistent AF recordings shows significant Endocardial-epicardial dissociation marked temporal heterogeneity, discordant and transitioning wavefronts patterns and complex fractionations. No sustained focal activity was observed. Such complex 3-dimensional interactions provide insight into why endocardial mapping alone may not fully characterize the AF mechanism and why endocardial ablation may not be sufficient. Graphic Abstract: A graphic abstract is available for this article.

Background: The key drivers of symptom severity and health-related quality of life (hr-QOL) in patients with atrial fibrillation (AF) remain unclear. We aimed to determine the relative contribution to symptom severity and hr-QOL of clinical factors including left ventricular (LV) diastolic function and ventricular rate control during AF and of psychological functioning.Methods: Seventy-eight consecutive patients with symptomatic AF and preserved LV systolic function underwent detailed evaluation of i) AF symptom severity and hr-QOL; ii) clinical factors including left ventricular (LV) diastolic function, AF burden, and ventricular rate during AF and iii) state and trait aspects of psychological functioning.Results: Moderate-to-severe AF-related symptoms were reported by 64% of the study population whilst 36% reported no more than mild symptoms. Worse symptom severity was associated with a higher score on the Perceived Stress Scale (16.7 +/- 4.4 vs. 5.4 +/- 4.4, p < 0.0001) and higher prevalence of the Type D Personality (20150 vs. 4/28, p = 0.012). In multivariable models, only a predisposition to subjectively appraise life situations as stressful (higher PSS score) and a personality with a higher degree of negative affectivity and social inhibition (higher TDPS score) were independent predictors of higher AF symptom severity and poorer hr-QOL. No clinical factors including AF burden, ventricular rates during AF or LV diastolic function were significant predictors of AF-specific symptoms or hr-QOL.Conclusion: In a tertiary AF population with preserved LV systolic function, only psychological functioning consistently predicts both AF-related symptoms and hr-QOL. LV diastolic function, AF burden, and ventricular rate during AF are not independent predictors.

Background Regular alcohol intake is an important modifiable risk factor associated with atrial fibrillation (AF) and left atrial (LA) dilation. Objective The purpose of this study was to determine the impact of different degrees of alcohol consumption on atrial remodeling using high-density electroanatomic mapping. Methods We enrolled 75 patients before AF ablation to undergo high-density LA mapping (CARTO, Biosense Webster) using a multipolar catheter. The Confidense algorithm was used to create maps during distal coronary sinus pacing at 600 ms. Bipolar voltage and complex atrial activity were assessed, and isochronal activation maps were created to determine global conduction velocity (CV). Patients were classified as lifelong nondrinkers, mild drinkers (2–7 drinks/week), or moderate drinkers (8–21 drinks/week). Results High-density electroanatomic mapping (mean 1016 ± 445 points per patient) was performed on 25 lifelong nondrinkers, 25 mild drinkers (4.4 ± 2.3 drinks/week), and 25 moderate drinkers (14.0 ± 4.2 drinks/week). Moderate drinkers had significantly lower mean global bipolar voltages (1.53 ± 0.62 mV vs 1.89 ± 0.45 mV; P = .02), slower CV (33.5 ± 14.4 cm/s vs 41.7 ± 12.1 cm/s; P = .04), and a higher proportion of complex atrial potentials (7.8% ± 4.7% vs 4.5% ± 2.7%; P = .004) compared to nondrinkers. Global voltage and CV did not differ significantly in mild drinkers, but there was a significant increase in global complex potentials (6.6% ± 4.6%; P = .04) and regional low-voltage zones ( Conclusion Regular moderate alcohol consumption, but not mild consumption, is an important modifiable risk factor for AF associated with lower atrial voltage and conduction slowing. These electrical and structural changes may explain the propensity to AF in regular drinkers.

Aims Obstructive sleep apnoea (OSA) associates with atrial fibrillation (AF), but the relationship of OSA severity and AF phenotype with the atrial substrate remains poorly defined. We sought to define the atrial substrate across the spectrum of OSA severity utilizing high-density mapping. Methods and results Sixty-six consecutive patients (male 71%, age 61 ± 9) having AF ablation (paroxysmal AF 36, persistent AF 30) were recruited. All patents underwent formal overnight polysomnography and high-density left atrial (LA) mapping (mean 2351 ± 1244 points) in paced rhythm. Apnoea–hypopnoea index (AHI) (mean 21 ± 18) associated with lower voltage (−0.34, P = 0.005), increased complex points (r = 0.43, P Conclusion High-density mapping observed that OSA associates with marked atrial remodelling, predominantly among paroxysmal AF cohorts with severe OSA. This may facilitate the identification of AF patients that stand to derive the greatest benefit from OSA management.

Background The 3-dimensional (3D) nature of sinoatrial node (SAN) function has not been characterized in the intact human heart. Objective The purpose of this study was to characterize the 3D nature of SAN function in patients with structural heart disease (SHD) using simultaneous endocardial–epicardial (endo–epi) phase mapping. Methods Simultaneous intraoperative endo–epi SAN mapping was performed during sinus rhythm at baseline (SRbaseline) and postoverdrive suppression at 600 ms (SRpost-pace600) and 400 ms (SRpost-pace400) using 2 Abbott Advisor HD Grid Mapping Catheters. Unipolar and bipolar electrograms (EGMs) were exported for phase analysis to determine (1) activation exits; (2) wavefront propagation sequence; (3) endo–epi dissociation; and (4) fractionation. Comparison of these variables was made among the 3 rhythms from an endo–epi perspective. Results Sixteen patients with SHD were included. SRbaseline activations were unicentric and predominantly exited cranially (87.5%) with endo–epi synchrony. However, with overdrive suppression, a tendency for caudal exit shift and endo–epi asynchrony was observed: SRpost-pace600 vs SRbaseline: cranial endo 75% vs 87.5% (P = .046); cranial epi 68.8% vs 87.5% (P = 0.002); caudal endo 12.5% vs 6.2% (P = 0.215); caudal epi 25% vs 6.2% (P = .0003); and SRpost-pace400 vs SRbaseline: cranial endo 81.3% vs 87.5% (P = 0.335); cranial epi 68.7% vs 87.5% (P = 0.0034; caudal endo 12.5% vs 6.2% (P = .148); caudal epi 31.2% vs 6.2% (P = 0.0017), consistent with multicentricity. EGM fractionation was more prevalent with overdrive suppression. Conclusion During mapping of the intact human heart, SAN demonstrated redundancy of sinoatrial exits with postoverdrive shift in sites of earliest activation and epi–endo dissociation of sinoatrial exits.

Aims Prior studies have described a variety of mechanisms for atrial fibrillation (AF) originating in the right atrium (RA). In this study, we report a series of patients in whom an extensive right atrial free wall low-voltage zone (LVZ) served as the AF substrate. Methods and results Five patients with a clinical syndrome of paroxysmal AF and atrial tachycardia (AT) underwent electrophysiologic evaluation. Five patients (3 M; age 52 ± 7 years) had symptomatic paroxysmal AF for (28 ± 17 months) not responsive to medical therapy. At the initial EP study, AT was inducible in four patients and was spontaneous in one patient. In all patients, tachycardia instability precluded detailed AT mapping. Sinus or pace maps indicated an extensive LVZ in the lateral RA trabeculated free wall which consisted of regions of low amplitude complex signals interspersed between electrically silent areas. Radiofrequency ablation aimed at rendering the LVZ electrical inert was successful in eliminating AF in four of five patients. At a follow-up of 28 ± 15 months, one patient had an isolated recurrence of AF. However, two patients required repeat ablation for recurrent AT. Conclusion An extensive LVZ in the trabeculated RA free wall constitutes an unusual substrate for AF. These patients also demonstrate unstable ATs originating from the same zone. Radiofrequency ablation to render the low-voltage zone electrically inert is an effective strategy to manage AF and AT.

This study sought to assess the atrial electrophysiological properties and post-ablation outcomes in patients with atrial fibrillation (AF) with and without the rs2200733 single nucleotide variant.The phenotype associated with chromosome 4q25 of the AF-susceptibility locus remains unknown.In this study, 102 consecutive patients (ages 61 ± 9 years, 64% male) with paroxysmal or persistent AF were prospectively recruited prior to ablation. Patients were genotyped for rs2200733 and high-density left atrial (LA) electroanatomic maps were created using a multipolar catheter during distal coronary sinus (CS) pacing at 600 ms. Voltage, conduction velocity (CV), CV heterogeneity, and fractionated signals of 6 LA segments were determined. Arrhythmia recurrence was assessed by continuous device (51%) and Holter monitoring.Overall, 41 patients (40%) were single nucleotide variant carriers (38 heterozygous, 3 homozygous). A mean of 2,239 ± 852 points per patient were collected. Carriers had relatively increased CV heterogeneity (45.7 ± 7.5% vs. 35.9 ± 2.3%; p 0.001), complex signals (9.4 ± 2.9% vs 6.0 ± 1.2%; p = 0.008), regional LA slowing, or conduction block (31.7 ± 8.2% vs. 17.9 ± 1.9%; p = 0.013) particularly in the posterior and lateral walls. There were no differences in CV, voltage, atrial refractoriness, or sinus node function. At follow-up (median: 27 months; range 19 to 31 months), carriers had lower arrhythmia-free survival (51% vs. 80%; p = 0.003). On multivariable analysis, carrier status was independently associated with CV heterogeneity (p = 0.001), complex signals (p = 0.002), and arrhythmia recurrence (p = 0.019).These data provide the first evidence that the rs2200733-tagged haplotype alters LA electrical remodeling and is a determinant of long-term outcome following AF ablation. The molecular mechanisms underpinning these changes warrant further investigation.

Aims Obesity is associated with higher electrical cardioversion (ECV) failure in persistent atrial fibrillation (PeAF). For ease-of-use, many centers prefer patches over paddles. We assessed the optimum modality and shock vector, as well as the safety and efficacy of the Manual Pressure Augmentation (MPA) technique. Methods Patients with obesity (BMI ≥ 30) and PeAF undergoing ECV using a biphasic defibrillator were randomized into one of four arms by modality (adhesive patches or handheld paddles) and shock vector (anteroposterior [AP] or anteroapical [AA]). If the first two shocks (100 and 200 J) failed, then patients received a 200-J shock using the alternative modality (patch or paddle). Shock vector remained unchanged. In an observational substudy, 20 patients with BMI of 35 or more, and who failed ECV at 200 J using both patches/paddles underwent a trial of MPA. Results In total, 125 patients were randomized between July 2016 and March 2018. First or second shock success was 43 of 63 (68.2%) for patches and 56 of 62 (90.3%) for paddles (P = 0.002). There were 20 crossovers from patches to paddles (12 of 20 third shock success with paddles) and six crossovers from paddles to patches (three of six third shock success with patches). Paddles successfully cardioverted 68 of 82 patients compared with 46 of 69 using patches (82.9% vs 66.7%; P = 0.02). Shock vector did not influence first or second shock success rates (82.0% AP vs 76.6% AA; P = 0.46). MPA was successful in 16 of 20 (80%) who failed in both (patches/paddles), with 360 J required in six of seven cases. Conclusion Routine use of adhesive patches at 200 J is inadequate in obesity. Strategies that improve success include the use of paddles, MPA, and escalation to 360 J.

Objectives This study sought to determine the impact of regular alcohol consumption on left atrial (LA) mechanical and reservoir function. Background Earlier studies suggest that regular alcohol intake is associated with increased atrial fibrillation (AF) and LA dilatation. Methods This study prospectively enrolled 160 patients with paroxysmal or persistent AF to undergo 3-T cardiac magnetic resonance (CMR) imaging in sinus rhythm. Patients self-reported alcohol consumption in standard drinks (∼12 g alcohol) per week over the preceding 12 months and were categorized into 4 groups: 1) lifelong nondrinkers; 2) mild drinkers (3 to 10 standard drinks/week); 3) moderate drinkers (11 to 20 standard drinks/week); 4) heavy drinkers (>20 standard drinks/week). Permanent AF and cardiomyopathy were excluded. On CMR, maximum LA volume (LAmax) and minimum LA volume (LAmin), global LA emptying fraction (LAEF) as (LAmax − LAmin) / LAmax, and LA reservoir function as (LAmax − LAmin) / LAmin were calculated. Results Regular alcohol consumption (mean 15.8 ± 6.9 standard drinks/week, n = 120) was associated with larger LA size (LA volume index 50 ± 13 ml/m2 vs. 43 ± 12 ml/m2; p = 0.005), reduction in LAEF (40 ± 14% vs. 52 ± 15%; p Conclusions In patients with AF, habitual alcohol consumption is associated with significantly increased LA size and atrial mechanical dysfunction compared with nondrinkers.

Aims In patients with non-ischaemic cardiomyopathy (NICM), the mortality benefit of a primary prevention implantable cardioverter-defibrillator (ICD) has been challenged. Left ventricular (LV) scar identified by cardiac magnetic resonance (CMR) imaging is associated with a high risk of malignant arrhythmia in NICM. We aimed to determine the impact of LV scar on the mortality benefit from a primary prevention ICD in NICM. Methods and results We recruited 452 consecutive heart failure patients [New York Heart Association (NYHA) Class II/III] with NICM and LV ejection fraction ≤35% from a state-wide CMR service. All patients fulfilled European Society of Cardiology guidelines for primary prevention ICD implantation; however, the decision to implant was at the treating physician's discretion. Baseline clinical and CMR data were recorded prospectively and heart failure mortality risk (MAGGIC score) was calculated. The primary study outcome measurement was all-cause mortality based on presence or absence of ICD, stratified by LV scar. Median follow-up was 37.9 months and there was no difference in MAGGIC score between those who did and did not receive a primary prevention ICD (19.30 ± 5.46 vs. 18.90 ± 5.67, P = 0.50). In patients without LV scar, ICD implantation was not associated with improved mortality [hazard ratio (HR) = 1.22, 95% confidence interval (CI): 0.53-2.78, P = 0.64]. In patients with LV scar, ICD implantation was independently associated with reduced mortality (HR = 0.45, 95% CI: 0.26-0.77, P = 0.003). Conclusions In patients with NICM, primary prevention ICD implantation is only associated with reduced mortality in patients with LV scar. This may enable more effective selection of NICM patients for ICD implantation compared with current guidelines.

Objectives This study sought to determine if diffuse ventricular fibrosis improves in patients with atrial fibrillation (AF)-mediated cardiomyopathy following the restoration of sinus rhythm. Background AF coexists in 30% of heart failure (HF) patients and may be an underrecognized reversible cause of left ventricular systolic dysfunction. Myocardial fibrosis is the hallmark of adverse cardiac remodeling in HF, yet its reversibility is unclear. Methods Patients with persistent AF and an idiopathic cardiomyopathy (left ventricular ejection fraction [LVEF] ≤45%) were randomized to catheter ablation (CA) or ongoing medical rate control as a pre-specified substudy of the CAMERA-MRI (Catheter Ablation versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction—an MRI-Guided Multi-centre Randomised Controlled Trial) trial. All patients had cardiac magnetic resonance imaging scans (including myocardial T1 time), serum B-type natriuretic peptide, 6-min walk tests, and Short Form-36 questionnaires performed at baseline and 6 months. Sixteen patients with no history of AF or left ventricular systolic dysfunction were enrolled as normal controls for T1 time. Results Thirty-six patients (18 in each treatment arm) were included in this substudy. Demographics, comorbidities, and myocardial T1 times were well matched at baseline. At 6 months, patients in the CA group had a significant reduction in myocardial T1 time from baseline compared with the medical rate control group (−124 ms; 95% confidence interval [CI]: −23 to −225 ms; p = 0.0176), although it remained higher than that of normal controls at 6 months (p = 0.0017). Improvements in myocardial T1 time with CA were associated with significant improvements in absolute LVEF (+12.5%; 95% CI: 5.9% to 19.0%; p = 0.0004), left ventricular end-systolic volume (p = 0.0019), and serum B-type natriuretic peptide (−216 ng/l; 95% CI: −23 to −225 ng/l; p = 0.0125). Conclusions The improvement in LVEF and reverse ventricular remodeling following successful CA of AF-mediated cardiomyopathy is accompanied by a regression of diffuse fibrosis. This suggests timely treatment of arrhythmia-mediated cardiomyopathy may minimize irreversible ventricular remodeling.

Arrhythmia induced cardiomyopathies (AIC) refer to the collective condition of Arrhythmia, Tachycardia, and ectopy‐induced Cardiomyopathy. Atrial fibrillation (AF) and heart failure (HF) are modern epidemics that often coexist and exacerbate one another. We aim to provide an overview of the current understanding and evidence for treatment and management in AIC with a particular focus on AF‐mediated cardiomyopathy and suggest approaches to recognize, screen, and manage AIC.

Aims Rotor mapping and ablation have gained favour over the recent years as an emerging ablation strategy targeting drivers of atrial fibrillation (AF). Their efficacy, however, has been a topic of great debate with variable outcomes across centres. The aim of this study was to systematically review the recent medical literature to determine the medium-term outcomes of rotor ablation in patients with paroxysmal atrial fibrillation (PAF) and persistent atrial fibrillation (PeAF). Methods and results A systematic search of the contemporary scientific literature (PubMed and EMBASE) was performed in August 2017. Only studies assessing arrhythmia-free survival from rotor ablation of AF were included. We used the random-effects model to assess the primary outcome of pooled medium-term single-procedure AF-free survival for both PAF and PeAF. Success rates from multiple procedures and complication rates were also examined. We included 11 observational studies (4 PAF and 10 PeAF) with a total of 556 patients (166 PAF and 390 PeAF). Pooled single-procedure freedom from AF was 37.8% [95% confidence interval 5.6-86.3%] at a mean follow-up period of 13.8 ± 1.8 months for PAF and 59.2% (95% CI 41.4-74.9%) at a mean follow-up period of 12.9 ± 6 months for PeAF. There was a marked heterogeneity between studies (I2 = 93.8% for PAF and 88.3% for PeAF). The mean complication rate of rotor ablation among the reported studies was 3.4%. Conclusion The wide variability in success rate between different centres performing rotor ablations suggests that the optimal ablation strategy, particularly targeting rotors, is unclear. Results from randomized studies are necessary before this technique can be considered as an established clinical tool.

Objectives This study sought to characterize the biatrial substrate in heart failure (HF) and persistent atrial fibrillation (PeAF). Background Atrial fibrillation (AF) and HF frequently coexist; however, the contribution of HF to the biatrial substrate in PeAF is unclear. Methods Consecutive patients with PeAF and normal left ventricular (NLV) systolic function (left ventricular ejection fraction [LVEF] >55%) or idiopathic cardiomyopathy (LVEF ≤45%) undergoing AF ablation were enrolled. In AF, pulmonary vein (PV) cycle length (PVCL) was recorded via a multipolar catheter in each PV and in the left atrial appendage for 100 consecutive cycles. After electrical cardioversion, biatrial electroanatomic mapping was performed. Complex electrograms, voltage, scarring, and conduction velocity were assessed. Results Forty patients, 20 patients with HF (mean age: 62 ± 8.9 years; AF duration: 15 ± 11 months; LVEF: 33 ± 8.4%) and 20 with NLV (mean age: 59 ± 6.7 years; AF duration: 14 ± 9.1 months; p = 0.69; mean LVEF: 61 ± 3.6%; p Conclusions HF is associated with significantly reduced biatrial tissue voltage, fractionation, and prolongation of PVCL. Advanced biatrial remodeling may have implications for invasive and noninvasive rhythm control strategies in patients with AF and HF.

Background Atrial fibrillation (AF) and left ventricular systolic dysfunction (LVSD) frequently co-exist despite adequate rate control. Existing randomized studies of AF and LVSD of varying etiologies have reported modest benefits with a rhythm control strategy. Objectives The goal of this study was to determine whether catheter ablation (CA) for AF could improve LVSD compared with medical rate control (MRC) where the etiology of the LVSD was unexplained, apart from the presence of AF. Methods This multicenter, randomized clinical trial enrolled patients with persistent AF and idiopathic cardiomyopathy (left ventricular ejection fraction [LVEF] ≤45%). After optimization of rate control, patients underwent cardiac magnetic resonance (CMR) to assess LVEF and late gadolinium enhancement, indicative of ventricular fibrosis, before randomization to either CA or ongoing MRC. CA included pulmonary vein isolation and posterior wall isolation. AF burden post-CA was assessed by using an implanted loop recorder, and adequacy of MRC was assessed by using serial Holter monitoring. The primary endpoint was change in LVEF on repeat CMR at 6 months. Results A total of 301 patients were screened; 68 patients were enrolled between November 2013 and October 2016 and randomized with 33 in each arm (accounting for 2 dropouts). The average AF burden post-CA was 1.6 ± 5.0% at 6 months. In the intention-to-treat analysis, absolute LVEF improved by 18 ± 13% in the CA group compared with 4.4 ± 13% in the MRC group (p Conclusions AF is an underappreciated reversible cause of LVSD in this population despite adequate rate control. The restoration of sinus rhythm with CA results in significant improvements in ventricular function, particularly in the absence of ventricular fibrosis on CMR. This outcome challenges the current treatment paradigm that rate control is the appropriate strategy in patients with AF and LVSD. (Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction [CAMERA-MRI]; ACTRN12613000880741)

Introduction The right atrium (RA) is readily accessible; however, it is unclear whether changes in the RA are representative of the LA. We performed detailed bi-atrial electroanatomic mapping to determine the electrophysiological relationship between the atria. Methods and results Consecutive patients with persistent AF underwent bi-atrial electroanatomical mapping with a contact force catheter acquiring points with a CF > 10 g prior to ablation. Points were analyzed for tissue voltage, complex electrograms, low voltage (

Background Evidence for epicardial-endocardial breakthrough (EEB) is derived from mapping inferences in patients with atrial fibrillation who may also have focal activations. Objective The purpose of this study was to investigate whether EEB could be discerned during stable right atrial (RA) macroreentry using high-density high-spatial resolution 3-dimensional mapping. Methods Macroreentry was diagnosed using 3-dimensional mapping and entrainment. Bipolar maps were reviewed for EEB defined as (1) presence of focal endocardial activation with radial spread unaccounted for by an endocardial wavefront and (2) present with the same timing on every tachycardia cycle. The EEB site was always in proximity to a line of endocardial conduction slowing or block. Distance and conduction velocity from the line of block to the EEB site was calculated. Electrograms at EEB sites were individually analyzed for morphology and to confirm direction of activation. Entrainment was performed at EEB sites. Results Twenty-six patients were studied. Fourteen examples of EEB were seen: 11 at the posterior RA (4 at the superior portion of the posterior wall and 7 at the inferior section) and 1 each at the cavotricuspid isthmus postablation, RA septum, and inferolateral RA. The mean area of the EEB site was 0.6 ± 0.2 cm2. A mean of 79.5% ± 18.6% of unipolar electrograms at the EEB site demonstrated an rS morphology. The mean distance and conduction velocity from the line of endocardial block to the EEB site at the posterior RA was 13.6 ± 2.3 mm and 59.3 ± 12.3 cm/s, respectively. In 4 patients, entrainment demonstrated that EEB sites were within the circuit and in 1 of these patients critical to arrhythmia maintenance. Activation maps during tachycardia and coronary sinus pacing demonstrated EEB at the same anatomic site. Conclusion EEB sites were demonstrated in stable atrial macroreentry supported by systematic entrainment confirmation and demonstration of the same phenomenon during pacing.

Adenosine may unmask dormant PV conduction and facilitate consolidation of PV isolation. We performed a meta-analysis to determine the impact of adenosine administration on clinical outcomes in patients undergoing PVI.References and electronic databases reporting AF ablation and adenosine following PVI were searched through to 22nd November 2015. The impact of adenosine on freedom from AF was assessed in twenty publications after radiofrequency ablation (RFA), and in four publications after cryoablation to achieve PVI. Relative risks were calculated and combined in a meta-analysis using random effects modeling.In patients undergoing RFA with adenosine challenge, there was a significant reduction in freedom from AF in patients with versus without adenosine induced reconnection (RR 0.86; 95%CI 0.77-0.98; p=0.02) particularly if no further ablation was performed (RR 0.66; 95%CI 0.50-0.87; p0.01). There was no difference when comparing outcomes in studies of routine adenosine challenge vs no adenosine (RR 1.07; 95%CI 0.93-1.22; p=0.36). There was a non-significant trend to an increase in freedom from AF in patients receiving routine adenosine challenge (RR 1.18 95%CI 0.99-1.42; p=0.07) in non-randomized studies using cryoablation.Adenosine induced PV reconnection following PVI is associated with a significant increase in AF recurrence, particularly if the reconnection sites are not targeted for ablation. The routine use of adenosine may be beneficial in AF ablation if given early post-PVI, at sufficient dose and reconnection is ablated.

Excessive alcohol consumption is associated with incident atrial fibrillation and adverse atrial remodeling; however, the effect of abstinence from alcohol on secondary prevention of atrial fibrillation is unclear.We conducted a multicenter, prospective, open-label, randomized, controlled trial at six hospitals in Australia. Adults who consumed 10 or more standard drinks (with 1 standard drink containing approximately 12 g of pure alcohol) per week and who had paroxysmal or persistent atrial fibrillation in sinus rhythm at baseline were randomly assigned in a 1:1 ratio to either abstain from alcohol or continue their usual alcohol consumption. The two primary end points were freedom from recurrence of atrial fibrillation (after a 2-week "blanking period") and total atrial fibrillation burden (proportion of time in atrial fibrillation) during 6 months of follow-up.Of 140 patients who underwent randomization (85% men; mean [±SD] age, 62±9 years), 70 were assigned to the abstinence group and 70 to the control group. Patients in the abstinence group reduced their alcohol intake from 16.8±7.7 to 2.1±3.7 standard drinks per week (a reduction of 87.5%), and patients in the control group reduced their alcohol intake from 16.4±6.9 to 13.2±6.5 drinks per week (a reduction of 19.5%). After a 2-week blanking period, atrial fibrillation recurred in 37 of 70 patients (53%) in the abstinence group and in 51 of 70 patients (73%) in the control group. The abstinence group had a longer period before recurrence of atrial fibrillation than the control group (hazard ratio, 0.55; 95% confidence interval, 0.36 to 0.84; P = 0.005). The atrial fibrillation burden over 6 months of follow-up was significantly lower in the abstinence group than in the control group (median percentage of time in atrial fibrillation, 0.5% [interquartile range, 0.0 to 3.0] vs. 1.2% [interquartile range, 0.0 to 10.3]; P = 0.01).Abstinence from alcohol reduced arrhythmia recurrences in regular drinkers with atrial fibrillation. (Funded by the Government of Victoria Operational Infrastructure Support Program and others; Australian New Zealand Clinical Trials Registry number, ACTRN12616000256471.).

Catheter ablation for atrial fibrillation (AF) is indicated in symptomatic patients who are intolerant or refractory to antiarrhythmic therapy. However, outcomes from catheter ablation remain suboptimal in patients with persistent AF. Pulmonary vein antral isolation (PVAI) is established as the cornerstone of AF ablation strategies. The landmark STAR AF II study demonstrated a lack of incremental benefit with adjunctive linear and complex fractionated electrogram ablation beyond PVAI. Randomized studies thus far have failed to consistently show favorable outcomes from other trigger/substrate-based ablation approaches over PVAI alone. In this issue of the journal, we pose an interesting clinical scenario-of a middle-aged female who presents with recurrent persistent AF but was found to have enduring PVAI on repeat electrophysiologic study. Which approach should be undertaken next? In this review article, we aim to provide an overview of ablation strategies beyond PVAI. Finally in light of scant randomized data to guide decision making we have approached leading experts in the field to provide their approach to this scenario.

Background: Nutraceuticals are pharmacologically active substances extracted from vegetable or animal food and administered to produce health benefits. We recently reviewed the current evidence for nutraceuticals in patients diagnosed with heart failure as part of the writing of the Australian Guidelines for the prevention, diagnosis, and management of heart failure. Methods: A systematic search for studies that compared nutraceuticals to standard care in adult patients with heart failure was performed. Studies were included if >50 patients were enrolled, with ≥6 months follow-up. If no studies met criteria then studies

Objectives The goal of this study was to characterize, in detail, focal atrial tachycardia (AT) arising from the crista terminalis to investigate associations with other atrial arrhythmia and to define long-term ablation outcomes. Background The crista terminalis is known to be the most common site of origin for focal AT, but it is not well characterized. Methods This study retrospectively identified a total of 548 ablation procedures for AT performed at a single center over a 16-year period, of which 171 were arising from the crista terminalis. Results Compared with patients with other AT sites of origin, crista terminalis AT patients were older (57.3 vs. 47.3 years), more commonly female (72.9% vs. 59.1%), were more commonly associated with coexistent atrioventricular nodal re-entry tachycardia (17.1% vs. 9.7%), and were more likely to be inducible with programmed stimulation (81.5% vs. 58.9%). There was preferential conduction in the superior-inferior axis along the crista terminalis. Acute ablation success rate was high (92.2%) and improved significantly when three-dimensional mapping was used (98.5%). Recurrence in the first 12 months after a successful ablation was 9.7%. Only 2 patients developed atrial fibrillation over the long-term follow-up of >7 years. Conclusions This large series characterized the clinical and electrophysiological features and immediate and long-term ablation outcomes for AT originating from the crista terminalis. Features of the tachycardia suggest that age-related localized remodeling of the crista terminalis causes a superficial endocardial zone of conduction slowing leading to re-entry. Ablation outcomes were good, with long-term freedom from atrial arrhythmia.

Alcohol is popular in Western culture, supported by a perception that modest intake is cardioprotective. However, excessive drinking has detrimental implications for cardiovascular disease. Atrial fibrillation (AF) following an alcohol binge or the "holiday heart syndrome" is well characterized. However, more modest levels of alcohol intake on a regular basis may also increase the risk of AF. The pathophysiological mechanisms responsible for the relationship between alcohol and AF may include direct toxicity and alcohol's contribution to obesity, sleep-disordered breathing, and hypertension. We aim to provide a comprehensive review of the epidemiology and pathophysiology by which alcohol may be responsible for AF and determine whether alcohol abstinence is required for patients with AF.

The DORMANT-AF Study: Electrophysiological and Hemodynamic Assessment. DORMANT-AF StudyIntroduction: Electrophysiological and Hemodynamic Assessment. DORMANT-AF Study The significance of adenosine induced dormant pulmonary vein (PV) conduction in atrial fibrillation (AF) ablation remains controversial. The optimal dose of adenosine to determine dormant PV conduction is yet to be systematically explored. Methods and Results: Electrophysiological and Hemodynamic Assessment. DORMANT-AF Study Consecutive patients undergoing index AF ablation received 3 adenosine doses (12, 18, and 24 mg) in a randomized blinded order, immediately after pulmonary vein isolation (PVI). Electrophysiological (PR prolongation, AV block (AVB) and PV reconnection) and hemodynamic (BP) parameters were measured. A total, 339 doses (113/dose) assessed 191 PVs in 50 patients (66% male, 72% PAF, 52% hypertensive). Dormant PV conduction occurred in 28% of patients (16.5% [32] of PVs). All cases were associated with AVB (AVB: PV reconnection vs. no PV reconnection 100% vs. 83%, P = 0.007). AVB occurred more frequently at 24 mg versus 12 mg (92% vs. 82%, P = 0.019) but not versus 18 mg (91%, P = 0.62). AVB duration progressed between 12 mg (12.0 ± 8.9 seconds), 18 mg (16.1 ± 9.1 seconds, P = 0.001), and 24 mg (19.0 ± 9.3 seconds, P 110 kg (65% vs. 91% in 70–110 kg group, P < 0.001) in response to adenosine was seen. Conclusion: Electrophysiological and Hemodynamic Assessment. DORMANT-AF Study An adenosine dose producing AVB is required to unmask dormant PV conduction. AVB is significantly reduced in patients >110 kg. Weight and dosing variability may in part explain the conflicting results of studies evaluating the clinical utility of adenosine in PVI.

The goal of this study was to describe functional endocardial-epicardial dissociation (FEED), signal complexities, and three-dimensional activation dynamics of the human atrium with structural heart disease (SHD).SHD commonly predisposes to arrhythmias. Although progressive remodeling is implicated, direct demonstration of FEED in the human atrium has not been reported previously.Simultaneous intraoperative mapping of the endocardial and epicardial lateral right atrial wall was performed by using 2 high-density grid catheters during sinus rhythm, pacing drive (600 ms and 400 ms cycle length), and premature extrastimulation (PES). Unipolar electrograms (EGMs) were exported into custom-made software for activation and phase mapping. Difference of ≥20 ms between paired endocardial and epicardial electrodes defined dissociation. EGMs with ≥3 deflections were classified as fractionated.Sixteen patients (mean age 60.5 ± 4.1 years; 18.7% with a history of atrial fibrillation) with SHD (43% ischemia, 57% valvular disease) were included. A total of 9,218 EGMs were analyzed. Compared with sinus rhythm, phase and activation analyses showed significant FEED during pacing at 600 ms and 400 ms (phase mapping 22.4% vs. 10% [p 0.0001] and 25.8% vs. 10% [p 0.0001], respectively; activation mapping 25.4% vs. 7.8% [p 0.0001] and 27.7% vs. 7.8% [p 0.0001]) and PES (phase mapping 34% vs. 10% [p 0.0001]; activation mapping 29.5% vs. 7.8% [p 0.0001]). Fractionated EGMs occurred significantly more during PES compared with sinus rhythm (50.2% vs. 39.5%; p 0.0001). Activation patterns differed significantly during pacing drive and PES, with preferential epicardial exit during the latter (15.9% vs. 13.8%; p = 0.046).Simultaneous endocardial-epicardial mapping revealed significant FEED with signal fractionation and preferential epicardial breakthroughs with PES. Such complex three-dimensional interaction in electrical activation provides mechanistic insights into atrial arrhythmogenesis with SHD.

Background An association between atrial fibrillation ( AF ), anxiety, and depression is recognized, but the spectrum of psychological distress remains unclear. We aimed to characterize the severity and predictors of distress associated with AF in a tertiary population and its response to AF management. Methods and Results Seventy‐eight patients with symptomatic AF underwent evaluation, including of AF symptom severity, health‐related quality of life, psychological distress, suicidal ideation, and specific personality traits. Twenty participants underwent AF ablation and 58 were managed medically, with repeat assessments at 4, 8, and 12 months. Severe distress (Hospital Anxiety and Depression Scale score, ≥15/42) was identified in 27 of 78 (35%). Independent predictors were a personality marked by vulnerability to stress (Perceived Stress Scale: R 2 , 0.54; β=0.7±0.1; t=7.8; P R 2 , 0.47; β=0.7±0.1; t=6.7; P R 2 , 0.35; odds ratio, 1.22±0.06; P R 2 , 0.48; odds ratio, 1.43±0.14; P AF ablation (median AF burden 1% [0–1%] over 12 months) was associated with significant reductions in distress (Hospital Anxiety and Depression Scale score, 13.9±1.8 to 4.3±1.8; P P =0.02). Conclusions There was a high prevalence of severe psychological distress (35%) and of suicidal ideation (20%) in a tertiary AF population, with personality traits predicting both. Effective AF ablation was associated with significant improvements, suggesting AF itself may be a treatable causative factor of distress.

Light-to-moderate regular alcohol consumption has been associated with reduced mortality, heart failure, and sudden death, with a well described "U-shaped" relationship. We sought to determine whether markers of diffuse ventricular fibrosis as assessed by cardiac magnetic resonance imaging (CMR) T1 mapping differ between nondrinkers and regular drinkers. We prospectively recruited 165 participants to undergo 3T CMR ventricular T1 mapping which included 120 regular light-to-moderate drinkers (7 to 28 standard drinks per week for >12 months) and 45 age and gender-matched nondrinking controls (1 standard drink ∼12 g alcohol). Diffuse ventricular fibrosis was assessed using ShMOLLI T1 mapping sequences performed in mid-short axis. Native T1, postcontrast T1 times and extracellular volume were compared in the left ventricle between regular drinkers and lifelong nondrinkers. In total 165 participants (mean age 59 ± 12 years, 70% male, 36% hypertension, mean LVEF 58 ± 11%) underwent CMR. Moderate alcohol intake (mean alcohol intake 16 ± 6 SDs/week) was associated with lower markers of diffuse ventricular fibrosis: native T1 time 1140 ± 47 vs 1173 ± 39 ms, p < 0.001; postcontrast T1 time 470 ± 47 vs 445 ± 43 ms, p = 0.01; extracellular volume 25.0 ± 2.7% vs 27.0 ± 2.8%, p = 0.003 despite similar LV size (p = 0.55) and mass compared with nondrinkers (p = 0.78). Quantity of alcohol intake and beverage type did not predict lower native T1 times. In conclusion, light-to-moderate or "social" alcohol consumption is associated with T1 changes on CMR suggestive of a reduction in diffuse ventricular fibrosis. These preliminary findings may provide some insights into the association between modest alcohol intake and reduction in sudden death and heart failure.