Automated three-dimensional activation versus conventional mapping for catheter ablation of atrial tachycardia - A prospective randomized trial.

Background: The automated NavX Ensite Precision latency-map (LM) algorithm aims to identify atrial tachycardia (AT) mechanisms. However, data on a direct comparison of this algorithm with conventional mapping are scarce. Methods: Patients scheduled for AT ablation were randomized to mapping with the LM- algorithm (LM group) or to conventional mapping (conventional only group: ConvO), using entrainment and local activation mapping techniques. Several outcomes were exploratively analyzed. Primary endpoint was intraprocedural AT Termination. If AT termination with only automated 3D-Mapping failed, additional conventional methods were applied (conversion). Results: A total of 63 patients (mean 67 years, 34 % female) were enrolled. In the LM group (n = 31), the correct AT mechanism was identified in 14 patients (45 %) using the algorithm alone compared to 30 patients (94 %) with conventional methods. Time to termination of the first AT was not different between groups (LM group 34 ± 20 vs. ConvO 43.1 ± 28.3 min; p = 0.2). However, when AT termination did not occur with LM algorithm, time to termination prolonged significantly (65 ± 35 min; p = 0.01). After applying conventional methods (conversion), procedural termination rates did not differ between LM group (90 %) vs. ConvO (94 %) (p = 0.3). During a follow-up time of 20 ± 9 months, no differences were observed in clinical outcomes. Conclusion: In this small prospective, randomized study, the use of the LM algorithm alone may lead to AT termination, but less accurate than conventional methods.

A rare case of right heart failure with the necessity for veno-arterial extracorporeal membrane oxygenation following pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation.

Pulmonary vein stenosis (PVS) after radiofrequency energy-mediated percutaneous pulmonary vein isolation as a treatment option for atrial fibrillation is a serious complication and the prevalence in historical reports varies between 0% and 42%. Symptoms of PVS are nonspecific and can include general symptoms such as dyspnea, cough, recurrent pneumonia, and chest pain. Pathophysiologically it increases the postcapillary pressure in the pulmonary circuit and may result in pulmonary hypertension (PH). Misdiagnosis and delayed treatment are common. We here report a case of a 59-year-old female with a history of pulmonary vein ablation followed by progressive dyspnea (New York Heart Association IV), right heart failure, CPR, and the need for extracorporeal membrane oxygenation (ECMO). Further treatment strategy includes pulmonary vein dilatation and stenting of both the left superior pulmonary vein and left inferior pulmonary vein, as well as balloon dilatation of RIPV under temporary ECMO support. Symptomatic, severe PVS is a rare complication after catheter ablation of atrial fibrillation. PVS can result in life-threatening complications such as PH with acute right heart failure. Early diagnosis is crucial but challenging. Mechanical cardiopulmonary support by veno-arterial ECMO for bridging to angioplasty could be a lifesaving option.

Durable pulmonary vein isolation but not complex substrate ablation determines the type of arrhythmia recurrence after persistent atrial fibrillation ablation.

BACKGROUND: Complex ablation for persistent atrial fibrillation (AF) aims to modify the arrhythmogenic substrates to become incapable to perpetuate the arrhythmia. Ablation-associated determinants of atrial tachycardia (AT) rather than AF recurrences are unknown. The aim of the study was to evaluate the association between the type of arrhythmia recurrence and electrophysiological findings during redo procedures. METHODS: A total number of 384 consecutive patients with persistent AF underwent complex ablation consisting of PV isolation (PVI), biatrial electrogram-guided ablation, and linear ablation with the desired procedural endpoint of AF termination. Electrophysiological findings during redo procedures and its relation to AR type are the subject of this study. RESULTS: Overall, 177 (46%) patients underwent a second procedure. Patients with AT recurrences had significantly more often persistent PVI (47 vs. 25%; P = 0.002). Moreover, a higher number of recovered PVs were associated with AF recurrence (3 PVs recovered, AF = 16.1% vs. AT = 5.2%; P = 0.02; 4 PVs recovered, AF = 18.5% vs. AT = 6.3%; P = 0.01), regardless of the extent of substrate ablation during the first procedure. CONCLUSIONS: Durable PV isolation but not the extent of atrial substrate ablation determines the type of arrhythmia recurrence. Thus, the PVs may represent dominant perpetuators (and not only triggers) of persistent AF even in the presence of a significantly modified atrial substrate.

Acupuncture at the auricular branch of the vagus nerve enhances heart rate variability in humans: An exploratory study.

BACKGROUND: Recent animal and human studies have shown antiarrhythmic effects inhibiting inducibility of atrial fibrillation through low-level transcutaneous electrical stimulation at the auricular branch of the vagus nerve (ABVN). OBJECTIVE: The present study investigated effects of acupuncture at the ABVN on the autonomic cardiac nervous system in humans through analysis of heart rate and heart rate variability (HRV) parameters. METHODS: We enrolled 24 healthy male volunteers and compared acupuncture at the ABVN to placebo-acupuncture performed at the Ma-35 point (an acupuncture point used in traditional Chinese medicine to treat pain caused by gonarthrosis). An additional measurement without acupuncture served as control. We analyzed the following heart rate and HRV parameters: standard deviation of normal-to-normal intervals (SDNN), root mean square of successive R-R interval differences (RMSSD), high frequency (HF), low frequency (LF), LF/HF ratio. RESULTS: In comparison to placebo acupuncture, acupuncture at the ABVN led to a significant reduction in heart rate (approximately 4%-6%, P < .05) and an increase in overall HRV demonstrated by SDNN (approximately 19%, P < .05). RMSSD and power spectral density parameters (HF, LF, LF/HF) showed statistical trends (P < .1) induced by auricular acupuncture in favor of vagal tone. No relevant difference was shown between control and placebo group. CONCLUSION: Acupuncture of the region innervated by the ABVN may activate the parasympathetic nervous system, as suggested by reduction in heart rate and increase in SDNN. However, given the lack of clear significant changes in other HRV parameters, this effect seems modest and its evaluation requires further investigation.

Predictors of successful complex catheter ablation for persistent atrial fibrillation despite failure of targeted procedural arrhythmia termination.

INTRODUCTION: Procedural atrial fibrillation (AF) termination is considered as a predictor of long-term success after catheter ablation for persistent AF (persAF). However, some patients remain free of arrhythmia recurrences despite failure to achieve AF termination. The objective of this study was to assess long-term outcome and prognostic factors in patients undergoing complex ablation without procedural AF termination. METHODS AND RESULTS: This study comprised 419 patients (63.8 ± 10.2 years, 63.4% male) undergoing complex ablation for persAF. Patients without procedural AF termination (n = 137, 64.2 ± 9.7 years, 63.5% male) were categorized into patients who remained in sinus rhythm (SR) in long-term outcome (SR-group) and patients with recurrence of AF or atrial tachycardia (AT) (AR-group). During a follow-up (FU) of 19.6 ± 14.6 months, the SR-group consisted of 65 (47.5%) and the AR-group of 69 (50.4%) patients. Three patients (2.2%) were lost to FU. Left atrial appendage (LAA) flow velocity and left atrium volume index (LAVI) could be identified as predictors for long-term success. LAA flow velocity and baseline AF cycle length (AFCL) were significantly associated with the type of arrhythmia recurrence (AF vs AT), ie, higher values of both are predictive for AT rather than AF recurrences. Patients with a LAVI < 34.4 mL/m² and significant AFCL increase during the ablation procedure had rather AT than AF recurrences. CONCLUSION: Patients with an arrhythmia-free outcome despite failure of procedural AF termination during complex ablation for persAF are characterized by specific morphological and functional properties that are easy to obtain.

Correlation between atrial fibrillation driver locations and complex fractionated atrial electrograms in patients with persistent atrial fibrillation.

INTRODUCTION: The aim of this study was to evaluate a spatial correlation between active atrial fibrillation (AF) drivers measured by electrocardiographic imaging and complex fractionated atrial electrograms (CFAEs) in patients with persistent AF. METHODS: Sixteen patients with persistent AF were included. A biatrial geometry relative to an array of 252-body-surface-electrodes was obtained from a noncontrast computed tomography scan. The reconstructed unipolar AF electrograms were signal-processed (ECVUE™, CardioInsight Technologies Inc., Cleveland, OH, USA) to identify AF drivers. Before driver ablation, a biatrial mapping using the NavX system (St. Jude Medical, St. Paul, MN, USA) was performed to identify CFAEs. CFAE and driver regions were then quantified and compared. RESULTS: AF was terminated by driver ablation in 11/16 (70%) patients. The mean number of ablated driver regions was 4 ± 1 per patient. The most frequent driver locations were the inferior left atrium and coronary sinus, the right pulmonary veins, and the right atrium. In 49/63 (78%) of the driver locations, more than 75% of the driver site showed CFAEs. The mean ablated driver area was 58 ± 24 cm2 (19 ± 11% of total surface area). The mean CFAE area was 178 ± 59 cm2 (49 ± 16%). The percentage of non-ablated CFAE area was 76 ± 13% of total CFAEs. In 9/11 patients with AF termination, the termination site showed CFAEs. CONCLUSIONS: There is a significant overlap between AF driver regions identified by the ECVUE™ system and CFAE areas identified by the NavX system. AF driver regions are smaller and mostly embedded in larger CFAE areas. Selective ablation of drivers in CFAE areas seems sufficient to terminate persistent AF in the majority of patients.

Sustained atrial fibrillation increases the risk of anticoagulation-related bleeding in heart failure.

BACKGROUND: Oral anticoagulation therapy in individuals with atrial fibrillation (AF) reduces the risk of thromboembolic events at cost of an increased bleeding risk. Whether anticoagulation-related outcomes differ between patients with paroxysmal and sustained AF receiving anticoagulation is controversially discussed. METHODS: In the present analysis of the prospective multi-center cohort study thrombEVAL, the incidence of anticoagulation-related adverse events was analyzed according to the AF phenotype. Information on outcome was centrally recorded over 3 years, validated via medical records and adjudicated by an independent review panel. Study monitoring was provided by an independent institution. RESULTS: Overall, the sample comprised 1089 AF individuals, of whom n = 398 had paroxysmal AF and n = 691 experienced sustained AF. In Cox regression analysis with adjustment for potential confounders, sustained AF indicated an independently elevated risk of clinically relevant bleeding compared to paroxysmal AF [hazard ratio (HR) 1.40 (1.02; 1.93); P = 0.038]. For clinically relevant bleeding, a significant interaction of the pattern of AF type with concomitant heart failure (HF) was detected: HRHF 2.45 (1.51, 3.98) vs. HRno HF 0.85 (0.55, 1.34); Pinteraction = 0.003. In HF patients, sustained AF indicated also an elevated risk of major bleeding [HR 2.25 (1.26, 4.20); P = 0.006]. A simplified HAS-BLED score incorporating only information on age (> 65 years), bleeding history, and HF with sustained AF demonstrated better discriminative performance for clinically relevant bleeding than the original version: AUCHAS-BLED: 0.583 vs. AUCsimplifiedHAS-BLED: 0.642 (P = 0.004). CONCLUSIONS: In HF patients receiving oral anticoagulation, sustained AF indicates a substantially elevated risk of bleeding. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov , identifier: NCT01809015.

Atrial Fibrillation Manifestations Risk Factors and Sex Differences in a Population-Based Cohort (From the Gutenberg Health Study).

Sex differences in cardiovascular risk factors, cardiac structure and function, and disease and symptom burden in the common arrhythmia atrial fibrillation (AF) have not been investigated systematically at the population level. Cross-sectional data of 14,796 subjects (age range 35 to 74 years, 50.5% men) from the population-based Gutenberg Health Study were examined to show the distribution of cardiovascular risk factors by AF status and sex, and to determine sex-specific predictors for AF. The prevalence of AF was higher in men (4.3%) than in women (1.9%). Men had a worse cardiovascular risk factor profile, a higher prevalence of cardiovascular disease, but fewer symptoms than women. Age-adjusted Cox regressions showed sex interactions in the association of high-density lipoprotein-cholesterol, triglycerides, diabetes mellitus, coronary artery disease, myocardial infarction, generalized anxiety disorder, and heart rate with AF. After multivariable adjustment, sex interactions were seen for thickness of interventricular end-diastolic septum, odds ratio (OR) per standard deviation (SD), 95% confidence interval women: 0.9 (0.8, 1.1), men: 1.2 (1.1, 1.4), interaction p value = 0.02; left atrial diameter index, OR per SD women: 1.5 (1.3, 1.8), men: 1.9 (1.7, 2.1), interaction p value = 0.03; and myocardial infarction, OR women: 2.7 (1.3, 5.6), men: 0.7 (0.5, 1.1), interaction p value = 0.002. In conclusion, in our large cohort, we observed substantial sex differences in AF distribution and clinical characteristics including comorbidities, symptom burden, and structural cardiac changes.

Annoyance to different noise sources is associated with atrial fibrillation in the Gutenberg Health Study.

BACKGROUND: Annoyance is a common reaction in populations exposed to environmental noise and is associated with cardiovascular diseases. We investigated for the first time the existence of an association between noise annoyance and atrial fibrillation (AF). METHODS AND RESULTS: Cross-sectional data from 14,639 participants of the Gutenberg Health Study were collected between 2007 and 2012. Annoyance from road traffic, aircraft, railways, industrial/construction and neighbourhood noise during daytime and sleep were collected from all participants through questionnaires using a 5-point scale. AF was assessed via self-reported medical history and/or documentation of AF on the study electrocardiogram. 80% of the study participants were annoyed by noise to a certain degree. The major sources of annoyance during daytime and sleep were aircraft, road traffic and neighbourhood noise. We found significant associations between annoyance (per point increase) and AF for aircraft noise annoyance during daytime (odds ratio (OR) 1.04; 95% confidence interval (CI) 1.00-1.08) and during sleep (OR 1.09; 95% CI 1.05-1.13), road traffic noise annoyance during sleep (OR 1.15; 95% CI 1.08-1.22), neighbourhood noise annoyance during daytime (OR 1.14; 95% CI 1.09-1.20) and during sleep (OR 1.14; 95% CI 1.07-1.21), industrial noise annoyance during daytime (OR 1.11; 95% CI 1.04-1.18) and railway noise annoyance during sleep (OR 1.13; 95% CI 1.04-1.22). Different degrees of annoyance were not associated with changes in cardiovascular risk factors. DISCUSSION: The results suggest for the first time that noise annoyance is associated with AF. Further studies are warranted to gain insight in the mechanisms underlying the noise-annoyance-disease relationship.

Device Therapy for Rate Control: Pacing, Resynchronisation and AV Node Ablation.

Atrioventricular node ablation (AVNA) is generally reserved for patients whose atrial fibrillation (AF) is refractory all other therapeutic options, since the recipients will often become pacemaker dependent. In such patients, this approach may prove particularly useful, especially if a tachycardia-induced cardiomyopathy is suspected. Historically, an "ablate and pace" approach has involved AVNA and right ventricular pacing, with or without an atrial lead. There is also an evolving role for atrioventricular node ablation in patients with AF who require cardiac resynchronisation therapy for treatment of systolic heart failure. A mortality benefit over pharmacotherapy has been demonstrated in observational studies and this concept is being further investigated in multi-centre randomised control trials.

Multicentre evaluation of non-invasive biatrial mapping for persistent atrial fibrillation ablation: the AFACART study.

AIMS: Non-invasive electrocardiogram (ECG) mapping allows the activation of the entire atrial epicardium to be recorded simultaneously, potentially identifying mechanisms critical for atrial fibrillation (AF) persistence. We sought to evaluate the utility of ECG mapping as a practical tool prior to ablation of persistent AF (PsAF) in centres with no practical experience of the system. METHODS AND RESULTS: A total of 118 patients with continuous AF duration <1 year were prospectively studied at 8 European centres. Patients were on a median of 1 antiarrhythmic drug (AAD) that had failed to restore sinus rhythm. Electrocardiogram mapping (ECVUE™, CardioInsight, USA) was performed prior to ablation to map AF drivers (local re-entrant circuits or focal breakthroughs). Ablation targeted drivers depicted by the system, followed by pulmonary vein (PV) isolation, and finally left atrial linear ablation if AF persisted. The primary endpoint was AF termination. Totally, 4.9 ± 1.0 driver sites were mapped per patient with a cumulative mapping time of 16 ± 2 s. Of these, 53% of drivers were located in the left atrium, 27% in the right atrium, and 20% in the anterior interatrial groove. Driver-only ablation resulted in AF termination in 75 of the 118 patients (64%) with a mean radiofrequency (RF) duration of 46 ± 28 min. Acute termination rates were not significantly different amongst all 8 centres (P = 0.672). Ten additional patients terminated with PV isolation and lines resulting in a total AF termination rate of 72%. Total RF duration was 75 ± 27 min. At 1-year follow-up, 78% of the patients were off AADs and 77% of the patients were free from AF recurrence. Of the patients with no AF recurrence, 49% experienced at least one episode of atrial tachycardia (AT) which required either continued AAD therapy, cardioversion, or repeat ablation. CONCLUSION: Non-invasive mapping identifies biatrial drivers that are critical in PsAF. This is validated by successful AF termination in the majority of patients treated in centres with no experience of the system. Ablation targeting these drivers results in favourable AF-free survival at 1 year, albeit with a significant rate of AT recurrence requiring further management.