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Abstract Background Dexmedetomidine and propofol are common sedatives in intensive care units and for interventional procedures. Both may compromise sinus node function and atrioventricular conduction. The objective of this prospective, randomized study is to compare the effect of dexmedetomidine with propofol on sinus node function and atrioventricular conduction. Methods In a tertiary care center in Switzerland we included from September 2019 to October 2020 160 patients (65 ± 11 years old; 32% female) undergoing first ablation for atrial fibrillation by cryoballoon ablation or by radiofrequency ablation. Patients were randomly assigned to deep sedation with dexmedetomidine (DEX group) versus propofol (PRO group). A standard electrophysiological study was performed after pulmonary vein isolation with the patients still deeply sedated and hemodynamically stable. Results Eighty patients each were randomized to the DEX and PRO group. DEX group patients had higher baseline sinus cycle length (1022 vs. 1138 ms; p = 0.003) and longer sinus node recovery time (SNRT400; 1597 vs. 1412 ms; p = 0.042). However, both corrected SNRT and normalized SNRT did not differ. DEX group patients had longer PR interval (207 vs. 186 ms; p = 0.002) and AH interval (111 vs. 95 ms, p = 0.008), longer Wenckebach cycle length of the atrioventricular node (512 vs. 456 ms; p = 0.005), and longer atrioventricular node effective refractory period (390 vs. 344 ms; p = 0.009). QRS width and HV interval were not different. An arrhythmia, mainly atrial fibrillation, was induced in 33 patients during the electrophysiological study, without differences among groups (20% vs. 15%, p = 0.533). Conclusions Dexmedetomidine has a more pronounced slowing effect on sinus rate and suprahissian AV conduction than propofol, but not on infrahissian AV conduction and ventricular repolarization. These differences need to be taken into account when using these sedatives. Trial registration ClinicalTrials.gov number NCT03844841, 19/02/2019

Background Screening for atrial fibrillation (AF) may reveal incidental arrhythmias of relevance. The aim of this study was to describe incidental arrhythmias detected during screening for AF in the STAR‐FIB (Predicting SilenT AtRial FIBrillation in Patients at High Thrombembolic Risk) cohort study. Methods and Results In the STAR‐FIB cohort study, we screened hospitalized patients for AF with 3 repeat 7‐day Holter ECGs. We analyzed all Holter ECGs for the presence of the following incidental arrhythmias: (1) sinus node dysfunction, defined as sinus pause of ≥3 seconds’ duration; (2) second‐degree (including Wenckebach) or higher‐degree atrioventricular block (AVB); (3) sustained supraventricular tachycardia of ≥30 seconds’ duration; and (4) sustained ventricular tachycardia of ≥30 seconds’ duration. We furthermore report treatment decisions because of incidental arrhythmias. A total of 2077 Holter ECGs were performed in 794 patients (mean age, 74.7 years; 49% women), resulting in a mean cumulative duration of analyzable ECG signal of 414±136 hours/patient. We found incidental arrhythmias in 94 patients (11.8%). Among these were sinus node dysfunction in 14 patients (1.8%), AVB in 41 (5.2%), supraventricular tachycardia in 42 (5.3%), and ventricular tachycardia in 2 (0.3%). Second‐degree AVB was found in 23 patients (2.9%), 2:1 AVB in 10 (1.3%), and complete AVB in 8 (1%). Subsequently, 8 patients underwent pacemaker implantation, 1 for sinus node dysfunction (post‐AF conversion pause of 9 seconds) and 7 for advanced AVB. One patient had an implantable cardioverter‐defibrillator implanted for syncopal ventricular tachycardia. Conclusions Incidental arrhythmias were frequently detected during screening for AF in the STAR‐FIB study and resulted in device therapy in 1.1% of our cohort patients.

Background: Atrioventricular conduction abnormalities after transcatheter aortic valve implantation (TAVI) are common. The value of electrophysiological study (EPS) for risk stratification of high-grade atrioventricular block (HG-AVB) and guidance of permanent pacemaker (PPM) implantation is poorly defined. Objective: The purpose of this study was to identify EPS parameters associated with HG-AVB and determine the value of EPS-guided PPM implantation after TAVI. Methods: We performed a systematic review and meta-analysis of studies investigating the value of EPS parameters for risk stratification of TAVI-related HG-AVB and for guidance of PPM implantation among patients with equivocal PPM indications after TAVI. Results: Eighteen studies (1230 patients) were eligible. In 7 studies, EPS was performed only after TAVI, whereas in 11 studies EPS was performed both before and after TAVI. Overall PPM implantation rate for HG-AVB was 16%. AV conduction intervals prolonged after TAVI, with the AH and HV intervals showing the largest magnitude of changes. Pre-TAVI HV >70 ms and the absolute value of the post-TAVI HV interval were associated with subsequent HG-AVB and PPM implantation with odds ratios of 2.53 (95% confidence interval [CI] 1.11–5.81; P = .04) and 1.10 (95% CI 1.03–1.17; P = .02; per 1-ms increase), respectively. In 10 studies, PPM was also implanted due to abnormal EPS findings in patients with equivocal PPM indications post-TAVI (typically new left bundle branch block or transient HG-AVB). Among them, the rate of long-term PPM dependency was 57%. Conclusion: Selective EPS testing may assist in the risk stratification of post-TAVI HG-AVB and in the guidance of PPM implantation, especially in patients with equivocal PPM indications post-TAVI.

Background The interrelationships between left atrial appendage (LAA) dimensions and device following implantation are unknown. We aimed to analyze the impact of Watchman device implantation on LAA dimensions following its percutaneous closure and potential predictors of remodeling. Methods and Results All consecutive LAA closure procedures performed at 2 centers between November 2017 and December 2020 were included in the WATCH‐DUAL (Watchman 2.5 Versus Watchman FLX in a Dual‐Center Left Atrial Appendage Closure Cohort) registry. This study included patients who had pre‐ and postintervention computed tomography scan analysis. The LAA and device dimensions were measured in a centralized core lab by 3‐dimensional computed tomography scan reconstruction methods, focusing on the device landing zone. This analysis included 104 patients (age, 76.0 [range, 72.0–83.0] years; 72% men; 53% Watchman FLX; 47% Watchman 2.5). The baseline characteristics were comparable between Watchman 2.5 and Watchman FLX groups, except for the higher use of oversizing in the latter group. The median delay for computed tomography control was 49 (range, 43–64) days. The landing zone area (median, 446 [range, 363–523] versus 290 [222–366] mm2; P

Background Data on the incidence of arrhythmias, associated cardiac interventions, and outcome in patients with dextro‐transposition of the great arteries and atrial switch are scarce. Methods and Results In this multicenter analysis, we included adult patients with dextro‐transposition of the great arteries and atrial switch regularly followed up at 3 Swiss tertiary care hospitals. The primary outcome was a composite of left ventricular assist device, heart transplantation, and death. The secondary outcome was occurrence of ventricular tachycardia, ventricular fibrillation, or sudden cardiac death. We identified 207 patients (34% women; median age at last follow‐up, 35 years) with dextro‐transposition of the great arteries and atrial switch. Arrhythmias occurred in 97 patients (47%) at a median age of 22 years. A pacemaker or an implantable cardioverter‐defibrillator was implanted in 39 (19%) and 13 (6%) patients, respectively, and 33 (16%) patients underwent a total of 51 ablation procedures to target 60 intra‐atrial re‐entry tachycardias, 4 atrioventricular nodal re‐entry tachycardias, and 1 atrial fibrillation. The primary outcome occurred in 21 patients (10%), and the secondary outcome occurred in 18 patients (9%); both were more common in patients with concomitant ventricular septum defect than in those without (hazard ratio [HR], 3.06 [95% CI, 1.29–7.27], P=0.011; and HR, 3.62 [95% CI, 1.43–9.18], P=0.007, respectively). Conclusions In patients with dextro‐transposition of the great arteries and atrial switch reaching adulthood, arrhythmias occur in almost half of patients, and associated rhythm interventions are frequent. One‐tenth of those patients do not survive until the age of 35 years free from left ventricular assist device or heart transplantation, and the outcome is worse in patients with concomitant ventricular septum defect.

Abstract Background and objective The automated detection of atrial activations (AAs) recorded from intracardiac electrograms (IEGMs) during atrial fibrillation (AF) is challenging considering their various amplitudes, morphologies and cycle length. Activation time estimation is further complicated by the constant changes in the IEGM active zones in complex and/or fractionated signals. We propose a new method which provides reliable automatic extraction of intracardiac AAs recorded within the pulmonary veins during AF and an accurate estimation of their local activation times. Methods First, two recently developed algorithms were evaluated and optimized on 118 recordings of pulmonary vein IEGM taken from 35 patients undergoing ablation of persistent AF. The adaptive mathematical morphology algorithm (AMM) uses an adaptive structuring element to extract AAs based on their morphological features. The relative-energy algorithm (Rel-En) uses short- and long-term energies to enhance and detect the AAs in the IEGM signals. Second, following the AA extraction, the signal amplitude was weighted using statistics of the AA sequences in order to reduce over- and undersensing of the algorithms. The detection capacity of our algorithms was compared with manually annotated activations and with two previously developed algorithms based on the Teager–Kaiser energy operator and the AF cycle length iteration, respectively. Finally, a method based on the barycenter was developed to reduce artificial variations in the activation annotations of complex IEGM signals. Results The best detection was achieved using Rel-En, yielding a false negative rate of 0.76% and a false positive rate of only 0.12% (total error rate 0.88%) against expert annotation. The post-processing further reduced the total error rate of the Rel-En algorithm by 70% (yielding to a final total error rate of 0.28%). Conclusion The proposed method shows reliable detection and robust temporal annotation of AAs recorded within pulmonary veins in AF. The method has low computational cost and high robustness for automatic detection of AAs, which makes it a suitable approach for online use in a procedural context.

Background This study was conducted to explore the association of different phenotypes, count, and location of chronic covert brain infarctions (CBIs) with detection of atrial fibrillation (AF) on prolonged post‐stroke cardiac rhythm monitoring (PCM). Methods and Results We conducted a cohort single‐center study of consecutive first‐ever ischemic stroke or transient ischemic attack patients undergoing PCM between January 2015 and December 2017. We blindly rated CBI phenotypes according to established definitions and white matter hyperintensities (WMHs) according to the age‐related white matter changes rating scale. We used (multiple) regression models to assess the association of the imaging biomarkers and incident AF on PCM. A total of 795 patients (median [interquartile range]) aged 69 (57–78) years, 41% women, median National Institutes of Health Stroke Scale score 2 (0–5), median PCM duration 14 (7–14) days, and AF detection in 61 patients (7.7%) were included. On univariate analysis, WMHs (per point odds ratio, 1.35 [95% CI, 1.03–1.78]) but not CBIs (odds ratio, 0.90 [95% CI, 0.52–1.56]) were associated with AF detection. Neither CBI phenotype, count, nor location were associated with AF detection. After adjustment for age, hypertension, and stroke severity, neither increasing WMHs (per point adjusted odds ratio, 0.85 [95% CI, 0.60–1.20]) nor CBIs (adjusted odds ratio, 0.60 [95% CI, 0.33–1.09]) were independently associated with AF detection. Conclusions Although WMHs and CBIs represent surrogate biomarkers of vascular risk factors, neither WMHs nor CBIs, including their phenotypes, count, and location, were independently associated with AF detection on PCM. In patients with manifest ischemic stroke or transient ischemic attack, the presence of imaging biomarkers of chronic ischemic injury does not seem promising to further refine prediction tools for AF detection on PCM.

BackgroundAtrial fibrillation (AF) is associated with cognitive dysfunction. However, neurocognitive function in AF patients undergoing pulmonary vein isolation (PVI) has not been well studied. The aim of this analysis is to compare neurocognitive function in patients who did or did not undergo PVI.Materials and methodsWe used data from the Swiss Atrial Fibrillation Cohort study (Swiss-AF), a prospective, observational, multicenter study in Switzerland. Patients with documented AF were enrolled and data of 1,576 patients without history of PVI and with complete information on PVI status and neurocognitive function were used. Information on PVI was collected at baseline and during 1 year of follow-up. Neurocognitive testing was performed at baseline and after 1 year of follow-up, using the Montreal Cognitive Assessment (MoCA), trail making test (TMT) A and B, digit symbol substitution test (DSST) and semantic fluency test (SFT). To investigate the association of PVI with neurocognitive function, we use propensity score matching (1:3) and inverse probability of treatment weighting (IPTW).ResultsThe mean age of this population was 74 ± 8 years, 27.1% were women. Overall, 88 (5.5%) patients underwent PVI during 1 year of follow-up. Using ITPW (n = 1576), PVI was weakly associated with the MoCA score after adjusting for time since PVI, baseline MoCA score and other covariates (β (95%CI) 1.19 (0.05; 2.32), p = 0.04). In the propensity matched comparison (n = 352), there was no significant association between PVI and the MoCA score (β (95%CI) 1.04 (−0.19; 2.28), p = 0.1). There were no significant associations between PVI and cognitive function when using the TMT A and B, DSST or SFT independent of the method used.ConclusionIn this population of AF patients, there was no consistent evidence of an association between PVI and neurocognitive function.Clinical trial registration[https://clinicaltrials.gov/], identifier [NCT02105844].

Objective To examine sex differences in prevalence, volume and distribution of vascular brain lesions on MRI among patients with atrial fibrillation (AF).Methods In this cross-sectional analysis, we included 1743 patients with AF (27% women) from the multicentre Swiss Atrial Fibrillation study (SWISS-AF) with available baseline brain MRI. We compared presence and total volume of large non-cortical or cortical infarcts (LNCCIs), small non-cortical infarcts, microbleeds (MB) and white matter hyperintensities (WMH, Fazekas score ≥2 for moderate or severe degree) between men and women with multivariable logistic regression. We generated voxel-based probability maps to assess the anatomical distribution of lesions.Results We found no strong evidence for an association of female sex with the prevalence of all ischaemic infarcts (LNCCI and SNCI combined; adjusted OR 0.86, 95% CI 0.67 to 1.09, p=0.22), MB (adjusted OR 0.91, 95% CI 0.68 to 1.21, p=0.52) and moderate or severe WMH (adjusted OR 1.15, 95% CI 0.90 to 1.48, p=0.27). However, total WMH volume was 17% larger among women than men (multivariable adjusted multiplicative effect 1.17, 95% CI 1.01 to 1.35; p=0.04). Lesion probability maps showed a right hemispheric preponderance of ischaemic infarcts in both men and women, while WMH were distributed symmetrically.Conclusion Women had higher white matter disease burden than men, while volume and prevalence of other lesions did not differ. Our findings highlight the importance of controlling risk factors for cerebral small vessel disease in patients with AF, especially among women.

BackgroundTranscatheter aortic valve implantation (TAVI) is associated with new onset brady- and tachyarrhythmias which may impact clinical outcome.AimsTo investigate the true incidence of new onset arrhythmias within 12 months after TAVI using an implantable cardiac monitor (ICM).MethodsOne hundred patients undergoing TAVI received an ICM within 3 months before or up to 5 days after TAVI. Patients were followed-up for 12 months after discharge from TAVI for the occurrence of atrial fibrillation (AF), bradycardia (≤30 bpm), advanced atrioventricular (AV) block, sustained ventricular and supraventricular tachycardia.ResultsA previously undiagnosed arrhythmia was observed in 31 patients (31%) and comprised AF in 19 patients (19%), advanced AV block in 3 patients (3%), and sustained supraventricular and ventricular tachycardia in 10 (10%) and 2 patients (2%), respectively. Three patients had a clinical diagnosis of sick-sinus-syndrome. A permanent pacemaker (PPM) was implanted in six patients (6%). The prevalence of pre-existing AF was 28%, and 47% of the patients had AF at the end of the study period. AF burden was significantly higher in patients with pre-existing [26.7% (IQR 0.3%; 100%)] compared to patients with new-onset AF [0.0% (IQR 0.0%; 0.06%); p = 0.001]. Three patients died after TAVI without evidence of an arrhythmic cause according to the available ICM recordings.ConclusionsRhythm monitoring for 12 months after TAVI revealed new arrhythmias, mainly AF, in almost one third of patients. Atrial fibrillation burden was higher in patients with prevalent compared to incident AF. Selected patients may benefit from short-term remote monitoring.Trial Registrationhttps://clinicaltrials.gov/: NCT02559011.

Background Diabetes is a major risk factor for atrial fibrillation (AF). However, it remains unclear whether individual AF phenotype and related comorbidities differ between patients who have AF with and without diabetes. This study investigated the association of diabetes with AF phenotype and cardiac and neurological comorbidities in patients with documented AF. Methods and Results Participants in the multicenter Swiss‐AF (Swiss Atrial Fibrillation) study with data on diabetes and AF phenotype were eligible. Primary outcomes were parameters of AF phenotype, including AF type, AF symptoms, and quality of life (assessed by the European Quality of Life‐5 Dimensions Questionnaire [EQ‐5D]). Secondary outcomes were cardiac (ie, history of hypertension, myocardial infarction, and heart failure) and neurological (ie, history of stroke and cognitive impairment) comorbidities. The cross‐sectional association of diabetes with these outcomes was assessed using logistic and linear regression, adjusted for age, sex, and cardiovascular risk factors. We included 2411 patients with AF (27.4% women; median age, 73.6 years). Diabetes was not associated with nonparoxysmal AF (odds ratio [OR], 1.01; 95% CI, 0.81–1.27). Patients with diabetes less often perceived AF symptoms (OR, 0.74; 95% CI, 0.59–0.92) but had worse quality of life (β=−4.54; 95% CI, −6.40 to −2.68) than those without diabetes. Patients with diabetes were more likely to have cardiac (hypertension [OR, 3.04; 95% CI, 2.19–4.22], myocardial infarction [OR, 1.55; 95% CI, 1.18–2.03], heart failure [OR, 1.99; 95% CI, 1.57–2.51]) and neurological (stroke [OR, 1.39, 95% CI, 1.03–1.87], cognitive impairment [OR, 1.75, 95% CI, 1.39–2.21]) comorbidities. Conclusions Patients who have AF with diabetes less often perceive AF symptoms but have worse quality of life and more cardiac and neurological comorbidities than those without diabetes. This raises the question of whether patients with diabetes should be systematically screened for silent AF. Registration URL: https://www.clinicaltrials.gov; Unique Identifier: NCT02105844.

Background: The role of dominant frequency (DF) in tracking the efficiency of a stepwise catheter ablation (step-CA) in persistent atrial fibrillation (peAF) remains poorly studied. We hypothesized that the DF time-course during step-CA displays divergent patterns between patients in whom a step-CA successfully restores long-term sinus rhythm (SR) and those with recurrence.Methods: This study involved 40 consecutive patients who underwent a step-CA for peAF (sustained duration 19 ± 11 months). Dominant frequency was computed on electrograms recorded from the right and left atrial appendages (RAA; LAA) and the coronary sinus before and during the step-CA synchronously to the 12-lead ECG. Dominant frequency was defined as the highest peak within the power spectrum.Results: Persistent atrial fibrillation was terminated by a step-CA in 28 patients [left-terminated (LT)], whereas 12 patients remaining in AF after ablation [not left-terminated (NLT)] were cardioverted. Over a mean follow-up of 34 ± 14 months, all NLT patients had a recurrence. Among the 28 LT patients, 20 had a recurrence, while 8 remained in SR throughout follow-up. The RAA and V1 DF had the best predictive values of the procedural failure to terminate AF (area under the curve; AUC 0.84, p < 0.05). A decision tree model including a decrease in LAA DF ≥ 6.61% during the first 20 min following pulmonary vein isolation (PVI) and a baseline RAA DF

A 25-year-old male patient with a giant right atrium presented with atrial tachycardia. Electroanatomic mapping revealed micro–re-entry from a low-voltage zone in the region of the right atrial appendage. Linear ablations across the low-voltage zone terminated the tachycardia. The remaining right atrial tissue was electrically normal. (Level of Difficulty: Intermediate.)

Background: Consistently successful patient outcomes following catheter ablation (CA) for treatment of persistent atrial fibrillation (pers-AF) remain elusive. We propose an electrocardiogram (ECG) analysis designed to (1) refine selection of patients most likely to benefit from ablation, and (2) examine the temporal evolution of AF organization indices that could act as clinical indicators of ongoing ablation effectiveness and completeness.Method: Twelve-lead ECG was continuously recorded in 40 patients (61 ± 8 years) during stepwise CA (step-CA) procedures for treatment of pers-AF (sustained duration 19 ± 11 months). Following standard pre-processing, ECG signals were divided into 10-s epochs and labeled according to their temporal placement: pre-PVI (baseline), dur-PVI (during pulmonary vein isolation), and post-PVI (during complex-fractionated atrial electrograms and linear ablation). Instantaneous frequency (IF), adaptive organization index (AOI), sample entropy (SampEn) and f-wave amplitude (FWA) measures were calculated and analyzed during each of the three temporal steps. Temporal evolution of these measures was assessed using a statistical test for mean value transitions, as an indicator of changes in AF organization. Results were then compared between: (i) patients grouped according to step-CA outcome; (ii) patients grouped according to type of arrhythmia recurrence following the procedure, if applicable; (iii) within the same patient group during the three different temporal steps.Results: Stepwise CA patient outcomes were as follows: (1) left-atrium (LA) terminated, not recurring (LTN, n = 8), (2) LA terminated, recurring (LTR, n = 20), and (3) not LA terminated, all recurring at follow-up (NLT, n = 12). Among the LTR and NLT patients, recurrence occurred as AF in seven patients and atrial tachycardia or atrial flutter (AT/AFL) in the remaining 25 patients. The ECG measures indicated the lowest level of organization in the NLT group for all ablation steps. The highest organization was observed in the LTN group, while the LTR group displayed an intermediate level of organization. Regarding time evolution of ECG measures in dur-PVI and post-PVI recordings, stepwise ablation led to increases in AF organization in most patients, with no significant differences between the LTN, LTR, and NLT groups. The median decrease in IF and increase in AOI were significantly greater in AT/AFL recurring patients than in AF recurring patients; however, changes in the SampEn and FWA parameters were not significantly different between types of recurrence.Conclusion: Noninvasive ECG measures, though unable to predict arrhythmia recurrence following ablation, show the lowest levels of AF organization in patients that do not respond well to step-CA. Increasing AF organization in post-PVI may be associated with organized arrhythmia recurrence after a single ablation procedure.

AIMS OF THE STUDY Anticoagulation of patients with screen-detected atrial fibrillation may prevent ischaemic strokes. The STAR-FIB study programme aims to determine the age- and sex-specific prevalence of silent atrial fibrillation and to develop a clinical prediction model to identify patients at risk of undiagnosed atrial fibrillation in a hospitalised patient population. METHODS The STAR-FIB study programme includes a prospective cohort study and a case-control study of hospitalised patients aged 65–84 years, evenly distributed for both age and sex. We recruited 795 patients without atrial fibrillation for the cohort study (49.2% females; median age 74.8 years). All patients had three serial 7-day Holter ECGs to screen for silent atrial fibrillation. The primary endpoint will be any episode of atrial fibrillation or atrial flutter of ≥30 seconds duration. The age- and sex-specific prevalence of newly diagnosed atrial fibrillation will be estimated. For the case-control study, 120 patients with paroxysmal atrial fibrillation were recruited as cases (41.7% females; median age 74.6 years); controls will be randomly selected from the cohort study in a 2:1 ratio. All participants in the cohort study and all cases were prospectively evaluated including clinical, laboratory, echocardiographic and electrical parameters. A clinical prediction model for undiagnosed atrial fibrillation will be derived in the case-control study and externally validated in the cohort study. CONCLUSIONS The STAR-FIB study programme will estimate the age- and sex-specific prevalence of silent atrial fibrillation in a hospitalised patient population, and develop and validate a clinical prediction model to identify patients at risk of silent atrial fibrillation.

Background: Silent and overt ischemic brain lesions are common and associated with adverse outcome. Whether the CHA2DS2-VASc score and its components predict magnetic resonance imaging (MRI)-detected ischemic silent and overt brain lesions in patients with atrial fibrillation (AF) is unclear.Methods: In this cross-sectional analysis, patients with AF were enrolled in a multicenter cohort study in Switzerland. Outcomes were clinically overt, silent [in the absence of a history of stroke/transient ischemic attack (TIA)] and any MRI-detected ischemic brain lesions. Logistic regression analyses were performed to assess the relationship of the CHA2DS2-VASc score and its components with ischemic brain lesions. An adapted CHA2D-VASc score (excluding history of stroke/TIA) for the analyses of clinically overt and silent ischemic brain lesions was used.Results: Overall, 1,741 patients were included in the analysis (age 73 ± 8 years, 27.4% female). At least one ischemic brain lesion was observed in 36.8% (clinically overt: 10.5%; silent: 22.9%; transient ischemic attack: 3.4%). The CHA2D-VASc score was strongly associated with clinically overt and silent ischemic brain lesions {odds ratio (OR) [95% confidence interval (CI)] 1.32 (1.17–1.49), p < 0.001 and 1.20 (1.10–1.30), p < 0.001, respectively}. Age 65–74 years (OR 2.58; 95%CI 1.29–5.90; p = 0.013), age ≥75 years (4.13; 2.07–9.43; p < 0.001), hypertension (1.90; 1.28–2.88; p = 0.002) and diabetes (1.48; 1.00–2.18; p = 0.047) were associated with clinically overt brain lesions, whereas age 65–74 years (1.95; 1.26–3.10; p = 0.004), age ≥75 years (3.06; 1.98–4.89; p < 0.001) and vascular disease (1.39; 1.07–1.79; p = 0.012) were associated with silent ischemic brain lesions.Conclusions: A higher CHA2D-VASc score was associated with a higher risk of both overt and silent ischemic brain lesions.Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT02105844.

INTRODUCTION Sudden cardiac death caused by malignant arrhythmia can be prevented by the use of defibrillators. Although the wearable cardioverter defibrillator (WCD) can prevent such an event, its role in clinical practice is ill defined. We investigated the use of the WCD in Switzerland with emphasis on prescription rate, therapy adherence and treatment rate. MATERIALS AND METHODS The Swiss WCD Registry is a retrospective observational registry including patients using a WCD. Patients were included from the first WCD use in Switzerland until February 2018. Baseline characteristics and data on WCD usage were examined for the total study population, and separately for each hospital. RESULTS From 1 December 2011 to 18 February 2018, a total of 456 patients (67.1% of all WCDs prescribed in Switzerland and 81.1% of all prescribed in the participating hospitals) were included in the registry. Up to 2017 there was a yearly increase in the number of prescribed WCDs to a maximum of 271 prescriptions per year. The mean age of patients was 57 years (± 14), 81 (17.8%) were female and mean left ventricular ejection fraction (EF) was 32% (± 13). The most common indications for WCD use were new-onset ischaemic cardiomyopathy (ICM) with EF ≤35% (206 patients, 45.2%), new-onset nonischaemic cardiomyopathy (NICM) with EF ≤35% (115 patients, 25.2%), unknown arrhythmic risk (83 patients, 18.2%), bridging to implantable cardioverter-defibrillator implantation or heart transplant (37 patients, 8.1%) and congenital/inherited heart disease (15 patients, 3.3%). Median wear duration was 58 days (interquartile range [IQR] 31–94) with a median average daily wear time of 22.6 hours (IQR 20–23.2). Seventeen appropriate therapies from the WCD were delivered in the whole population (treatment rate: 3.7%) to a total of 12 patients (2.6% of all patients). The most common underlying heart disease in patients with a treatment was ICM (13/17, 76.5%). There were no inappropriate treatments. CONCLUSION The use of WCDs has increased in Switzerland over the years for a variety of indications. There is high therapy adherence to the WCD, and a treatment rate comparable to previously published registry data.

Ventricular tachycardia (VT) caused by myocardial scaring bears a significant risk of mortality and morbidity. Antiarrhythmic drug therapy (AAD) and catheter ablation remain the cornerstone of VT management, but both treatments have limited efficacy and potential adverse effects. Stereotactic body radiotherapy (SBRT) is routinely used in oncology to treat non-invasively solid tumors with high precision and efficacy. Recently, this technology has been evaluated for the treatment of VT. This review presents the basic underlying principles, proof of concept, and main results of trials and case series that used SBRT for the treatment of VT refractory to AAD and catheter ablation.

Background The incidence and predictors of atrial fibrillation (AF) progression are currently not well defined, and clinical AF progression partly overlaps with rhythm control interventions (RCIs). Methods and Results We assessed AF type and intercurrent RCIs during yearly follow‐ups in 2869 prospectively followed patients with paroxysmal or persistent AF. Clinical AF progression was defined as progression from paroxysmal to nonparoxysmal or from persistent to permanent AF. An RCI was defined as pulmonary vein isolation, electrical cardioversion, or new treatment with amiodarone. During a median follow‐up of 3 years, the incidence of clinical AF progression was 5.2 per 100 patient‐years, and 10.9 per 100 patient‐years for any RCI. Significant predictors for AF progression were body mass index (hazard ratio [HR], 1.03; 95% CI, 1.01–1.05), heart rate (HR per 5 beats/min increase, 1.05; 95% CI, 1.02–1.08), age (HR per 5‐year increase 1.19; 95% CI, 1.13–1.27), systolic blood pressure (HR per 5 mm Hg increase, 1.03; 95% CI, 1.00–1.05), history of hyperthyroidism (HR, 1.71; 95% CI, 1.16–2.52), stroke (HR, 1.50; 95% CI, 1.19–1.88), and heart failure (HR, 1.69; 95% CI, 1.34–2.13). Regular physical activity (HR, 0.80; 95% CI, 0.66–0.98) and previous pulmonary vein isolation (HR, 0.69; 95% CI, 0.53–0.90) showed an inverse association. Significant predictive factors for RCIs were physical activity (HR, 1.42; 95% CI, 1.20–1.68), AF‐related symptoms (HR, 1.84; 95% CI, 1.47–2.30), age (HR per 5‐year increase, 0.88; 95% CI, 0.85–0.92), and paroxysmal AF (HR, 0.61; 95% CI, 0.51–0.73). Conclusions Cardiovascular risk factors and comorbidities were key predictors of clinical AF progression. A healthy lifestyle may therefore reduce the risk of AF progression.

BACKGROUND Several studies found that patients with atrial fibrillation (AF) have an increased risk of cognitive decline and dementia over time. However, the magnitude of the problem, associated risk factors and underlying mechanisms remain unclear. METHODS This article describes the design and methodology of the Swiss Atrial Fibrillation (Swiss-AF) Cohort Study, a prospective multicentre national cohort study of 2400 patients across 13 sites in Switzerland. Eligible patients must have documented AF. Main exclusion criteria are the inability to provide informed consent and the presence of exclusively short episodes of reversible forms of AF. All patients undergo extensive phenotyping and genotyping, including repeated assessment of cognitive functions, quality of life, disability, electrocardiography and cerebral magnetic resonance imaging. We also collect information on health related costs, and we assemble a large biobank. Key clinical outcomes in Swiss-AF are death, stroke, systemic embolism, bleeding, hospitalisation for heart failure and myocardial infarction. Information on outcomes and updates on other characteristics are being collected during yearly follow-up visits. RESULTS Up to 7 April 2017, we have enrolled 2133 patients into Swiss-AF. With the current recruitment rate of 15 to 20 patients per week, we expect that the target sample size of 2400 patients will be reached by summer 2017. CONCLUSION Swiss-AF is a large national prospective cohort of patients with AF in Switzerland. This study will provide important new information on structural and functional brain damage in patients with AF and on other AF related complications, using a large variety of genetic, phenotypic and health economic parameters.

Atrial fibrillation may be clearly symptomatic and is easily amenable to state-of-the-art treatment, most importantly oral anticoagulation therapy for the prevention of thromboembolism. However, atrial fibrillation may also go unnoticed for long periods in many patients. This silent or subclinical atrial fibrillation is nevertheless associated with thromboembolic risk just like clinically evident atrial fibrillation. Early detection of atrial fibrillation in patients at increased thromboembolic risk and consequent oral anticoagulation therapy may have a significant impact on public health. This review focuses on screening recommendations for atrial fibrillation and on the impact of silent atrial fibrillation in various clinical scenarios.

AIMS OF THE STUDY: Sudden cardiac arrest in athletes is a rare but dramatic event. The value of a routine electrocardiogram (ECG) during preparticipation screening (PPS) remains controversial, partly because of the relatively high number of false positive findings. Our study aimed to evaluate the prevalence of abnormal ECGs in consecutive Swiss elite athletes, overall and with regard to different sports classes, using modern screening criteria. METHODS: We analysed the 12-lead resting ECGs of high-level elite athletes (age ≥14 years) recorded at the Swiss Olympic Medical Centre Magglingen between 2013 and 2016 during routine PPS. The overall prevalence of abnormal ECGs was evaluated and compared in accordance with the original and revised Seattle criteria. Sports disciplines were categorised according to their static (estimated percentage of maximal voluntary contraction, I–III) and dynamic (estimated percentage of maximal oxygen uptake, A–C) components, and the prevalence of abnormal ECGs compared between sports classes by Fisher’s exact test (with alpha set at 0.05). RESULTS: ECGs from 287 consecutive athletes were analysed (64.1% male; 99.7% Caucasian; median age 20.4 ± 4.9 years; median weekly training volume 17.7 ± 7.1 hours). Based on original Seattle criteria, eight (2.8%) ECGs were classified as abnormal: three T-wave inversion (TWI), one Q-wave duration >40 ms, two QRS left axis deviation, two Q-wave amplitude >3 mm. The use of the revised Seattle criteria reduced the number of abnormal ECGs to four (1.4%): three TWI, one Q-wave duration >40 ms. Further cardiological work-up revealed an underlying structural heart disease in only one of these four athletes (inferolateral TWI on ECG), consisting of very localised mid-wall fibrosis suggestive of former myocarditis. There was a significant difference in occurrence of abnormal ECGs between the different sports categories (p = 0.018). All four abnormal ECGs according to the revised Seattle criteria occurred in the high dynamic sport classes (IIC and IIIC); three out of the four were found in the high dynamic high static class (IIIC). CONCLUSIONS: In our cohort of high-level elite athletes, the prevalence of abnormal ECGs according to modern screening criteria was very low. All athletes with an abnormal ECG performed high dynamic sports. Less than one percent of our athletes had a new relevant cardiac diagnosis.

Ablation of ventricular tachycardia (VT) by conventional radiofrequency ablation can be impossible if the ventricular wall at the targeted ablation site is very thick, as for example the ventricular septum. We present a case of a patient with incessant, non-sustained slow VT originating from the septal part of the lower outflow tracts. Radiofrequency catheter ablation from both ventricles as well as from the anterior cardiac vein were not successful. Both high power radiofrequency ablation and bipolar radiofrequency ablation neither were successfull. Finally, ethanol ablation of the first septal perforator successfully terminated arrhythmia. We discuss the possibilities to overcome failed conventional radiofrequency VT ablation of a septal focus.