Freedom from atrial fibrillation (AF) at 1 year can be achieved in 50–70% of patients undergoing catheter ablation. Recurrent AF early after ablation most commonly terminates spontaneously without further interventional treatment but is associated with later recurrent AF. The aim of this investigation is to identify clinical and procedural factors associated with recurrence of AF early after ablation. We retrospectively analysed data for recurrence of AF within the first 3 months after catheter ablation from the randomized controlled AXAFA–AFNET 5 trial, which demonstrated that continuous anticoagulation with apixaban is as safe and as effective compared to vitamin K antagonists in 678 patients undergoing first AF ablation. The primary outcome of first recurrent AF within 90 days was observed in 163 (28%) patients, in which 78 (48%) patients experienced an event within the first 14 days post-ablation. After multivariable adjustment, a history of stroke/transient ischaemic attack [hazard ratio (HR) 1.54, 95% confidence interval (CI) 0.93–2.6; P = 0.11], coronary artery disease (HR 1.85, 95% CI 1.20–2.86; P = 0.005), cardioversion during ablation (HR 1.78, 95% CI 1.26–2.49; P = 0.001), and an age:sex interaction for older women (HR 1.01, 95% CI 1.00–1.01; P = 0.04) were associated with recurrent AF. The P-wave duration at follow-up was significantly longer for patients with AF recurrence (129 ± 31 ms vs. 122 ± 22 ms in patients without AF, P = 0.03). Half of all early AF recurrences within the first 3 months post-ablation occurred within the first 14 days post-ablation. Vascular disease and cardioversion during the procedure are strong predictors of recurrent AF. P-wave duration at follow-up was longer in patients with recurrent AF. Clinicaltrials.gov identifier NCT02227550

Sleep disordered breathing (SDB) is known for fluctuating heart rates and an increased risk of developing arrhythmias. The current reference for heartbeat analysis is an electrocardiogram (ECG). As an unobtrusive alternative, we tested a sensor foil for mechanical vibrations to perform a ballistocardiography (BCG) and applied a novel algorithm for beat-to-beat cycle length detection. The aim of this study was to assess the correlation between beat-to-beat cycle length detection by the BCG algorithm and simultaneously recorded ECG. In 21 patients suspected for SDB undergoing polysomnography, we compared ECG to simultaneously recorded BCG data analysed by our algorithm. We analysed 362.040 heartbeats during a total of 93 hours of recording. The baseline beat-to-beat cycle length correlation between BCG and ECG was r _s = 0.77 (n = 362040) with a mean absolute difference of 15 ± 162 ms (mean cycle length: ECG 923 ± 220 ms; BCG 908 ± 203 ms). After filtering artefacts and improving signal quality by our algorithm, the correlation increased to r _s = 0.95 (n = 235367) with a mean absolute difference in cycle length of 4 ± 72 ms (ECG 920 ± 196 ms; BCG 916 ± 194 ms). We conclude that our algorithm, coupled with a BCG sensor foil provides good correlation of beat-to-beat cycle length detection with simultaneously recorded ECG.

Bioelectrical impedance spectroscopy (BIS) measures body composition, including fluid status. Acute decompensated heart failure (ADHF) is associated with fluid overload in different body compartments. This investigation aimed to evaluate the feasibility of measuring and monitoring fluid accumulation in patients with ADHF using BIS. The extracellular impedance as a surrogate marker for fluid accumulation was measured in 67 participants (25 healthy reference volunteers and 42 patients admitted with ADHF) using BIS in the “transthoracic”, “foot-to-foot”, “whole-body” and “hand-to-hand” segments. At baseline, BIS showed significantly lower extracellular resistance values for the “whole-body” (P < 0.001), “foot-to-foot” (P = 0.03), “hand-to-hand” (P < 0.001) and “transthoracic” (P = 0.014) segments in patients with ADHF than the reference cohort, revealing a specific pattern for peripheral, central and general fluid accumulation. The “foot-to-foot” (AUC = 0.8, P < 0.001) and “hand-to-hand” (AUC = 0.74, P = 0.04) segments indicated compartments of fluid accumulation with good prediction. During cardiac recompensation, BIS values changed significantly and were in line with routine parameters for monitoring ADHF. Mean bodyweight change per day correlated moderately to good with BIS values in the “whole-body” (r = −0.4), “foot-to-foot” (r = −0.8) and “transthoracic” (r = −0.4) segments. Based on our analysis, we conclude that measuring and monitoring fluid accumulation in ADHF using segmental BIS is feasible and correlates with clinical parameters during recompensation.

Aims: Postoperative atrial fibrillation (POAF) after cardiac surgery is an independent predictor of stroke and mortality late after discharge. We aimed to determine the burden and predictors of early (up to 5th postoperative day) and late (after 5th postoperative day) new-onset atrial fibrillation (AF) using implantable loop recorders (ILRs) in patients undergoing open chest cardiac surgery. Methods and results: Seventy-nine patients without a history of AF undergoing cardiac surgery underwent peri-operative high-resolution mapping of electrically induced AF and were followed 36 months after surgery using an ILR (Reveal XT™). Clinical and electrophysiological predictors of late POAF were assessed. POAF occurred in 46 patients (58%), with early POAF detected in 27 (34%) and late POAF in 37 patients (47%). Late POAF episodes were short-lasting (mostly between 2 min and 6 h) and showed a circadian rhythm pattern with a peak of episode initiation during daytime. In POAF patients, electrically induced AF showed more complex propagation patterns than in patients without POAF. Early POAF, right atrial (RA) volume, prolonged PR time, and advanced age were independent predictors of late POAF. Conclusions: Late POAF occurred in 47% of patients without a history of AF. Patients who develop early POAF, with higher age, larger RA, or prolonged PR time have a higher risk of developing late POAF and may benefit from intensified rhythm follow-up after cardiac surgery. Clinicaltrials.gov number: NCT01530750.

Background.Heart rate monitoring is especially interesting in patients with atrial fibrillation (AF) and is routinely performed by ECG. A ballistocardiography (BCG) foil is an unobtrusive sensor for mechanical vibrations. We tested the correlation of heartbeat cycle length detection by a novel algorithm for a BCG foil to an ECG in AF and sinus rhythm (SR).Methods.In 22 patients we obtained BCG and synchronized ECG recordings before and after cardioversion and examined the correlation between heartbeat characteristics.Results.We analyzed a total of 4317 heartbeats during AF and 2445 during SR with a correlation between ECG and BCG during AF ofr=0.70(95% CI 0.68–0.71,P<0.0001) andr=0.75(95% CI 0.73–0.77,P<0.0001) during SR. By adding a quality index, artifacts could be reduced and the correlation increased for AF to 0.76 (95% CI 0.74–0.77,P<0.0001,n=3468) and for SR to 0.85 (95% CI 0.83–0.86,P<0.0001,n=2176).Conclusion.Heartbeat cycle length measurement by our novel algorithm for BCG foil is feasible during SR and AF, offering new possibilities of unobtrusive heart rate monitoring. This trial is registered with IRB registration number EK205/11. This trial is registered with clinical trials registration numberNCT01779674.

Current guidelines recommend opportunistic screening for atrial fibrillation (AF) but the prognosis of individuals is unclear. The aim of this investigation is to determine prevalence and 1-year outcome of individuals with screen-detected AF. We performed a prospective, pharmacy-based single time point AF screening study in 7107 elderly citizens (≥65 years) using a hand-held, single-lead electrocardiogram (ECG) device. Prevalence of AF was assessed, and data on all-cause death and hospitalization for cardiovascular (CV) causes were collected over a median follow-up of 401 (372; 435) days. Mean age of participants was 74 ± 5.9 years, with 58% (N = 4130) of female sex. Automated heart rhythm analyses identified AF in 432 (6.1%) participants, with newly diagnosed AF in 3.6% of all subjects. During follow-up, 62 participants (0.9%) died and 390 (6.0%) were hospitalized for CV causes. Total mortality was 2.3% in participants with a screen-detected AF and 0.8% in subjects with a normal ECG [hazard ratio (HR) 2.94; 95% confidence interval (CI) 1.49–5.78; P = 0.002]; hospitalization for CV causes occurred in 10.6% and 5.5%, respectively (HR 2.08; 95% CI 1.52–2.84; P < 0.001). Compared with subjects without a history of AF at baseline and a normal ECG, participants with newly diagnosed or known AF had a significantly higher mortality risk with HRs of 2.64 (95% CI 1.05–6.66; P = 0.04) and 2.68 (95% CI 1.44–4.97; P = 0.002), respectively. After multivariable adjustment, screen-detected AF remained a significant predictor of death or hospitalization for CV causes. Pharmacy-based, automated AF screening in elderly citizens identified subjects with unknown AF and an excess mortality risk over the next year.