Although extending the duration of ambulatory electrocardiographic monitoring beyond 24 to 48 hours can improve the detection of arrhythmias, lead-based (Holter) monitors might be limited by patient compliance and other factors. We, therefore, evaluated compliance, analyzable signal time, interval to arrhythmia detection, and diagnostic yield of the Zio Patch, a novel leadless, electrocardiographic monitoring device in 26,751 consecutive patients. The mean wear time was 7.6 ± 3.6 days, and the median analyzable time was 99% of the total wear time. Among the patients with detected arrhythmias (60.3% of all patients), 29.9% had their first arrhythmia and 51.1% had their first symptom-triggered arrhythmia occur after the initial 48-hour period. Compared with the first 48 hours of monitoring, the overall diagnostic yield was greater when data from the entire Zio Patch wear duration were included for any arrhythmia (62.2% vs 43.9%, p <0.0001) and for any symptomatic arrhythmia (9.7% vs 4.4%, p <0.0001). For paroxysmal atrial fibrillation (AF), the mean interval to the first detection of AF was inversely proportional to the total AF burden, with an increasing proportion occurring after 48 hours (11.2%, 10.5%, 20.8%, and 38.0% for an AF burden of 51% to 75%, 26% to 50%, 1% to 25%, and <1%, respectively). In conclusion, extended monitoring with the Zio Patch for ≤14 days is feasible, with high patient compliance, a high analyzable signal time, and an incremental diagnostic yield beyond 48 hours for all arrhythmia types. These findings could have significant implications for device selection, monitoring duration, and care pathways for arrhythmia evaluation and AF surveillance.

Objectives To evaluate the association of digoxin with mortality in atrial fibrillation. Background Despite endorsement of digoxin in clinical practice guidelines, there exist limited data on its safety in atrial fibrillation and flutter (AF). Methods Using complete data from the US Department of Veterans Administration (VA) Health Care System, we identified patients with newly-diagnosed, non-valvular AF seen within 90 days in an outpatient setting between VA fiscal years 2004-2008. We used multivariate and propensity-matched Cox proportional hazards to evaluate the association of digoxin use to death. Residual confounding was assessed by sensitivity analysis. Results Of 122,465 patients with 353,168 person-years of follow-up (age 72.1±10.3 years, 98.4% males), 28,679 (23.4%) patients received digoxin. Cumulative mortality rates were higher for digoxin-treated patients than for untreated patients (95 vs. 67 per 1,000 person-years; P<0.001). Digoxin use was independently associated with mortality after multivariate adjustment (HR: 1.26, 95%CI: 1.23-1.29, P<0.001) and propensity matching (HR: 1.21, 95%CI: 1.17-1.25, P<0.001), even after adjustment for drug adherence. The risk of death was not modified by age, sex, heart failure, kidney function, or concomitant use of beta blockers, amiodarone, or warfarin. Conclusion Digoxin was associated with increased risk of death in patients with newly-diagnosed AF, independent of drug adherence, kidney function, cardiovascular comorbidities, and concomitant therapies. These findings challenge current cardiovascular society recommendations on use of digoxin in AF.

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Objective To evaluate warfarin prescription, quality of International Normalized Ratio (INR) monitoring, and of INR control in patients with atrial fibrillation (AF) and chronic kidney disease. Methods We performed a retrospective cohort study of patients with newly diagnosed AF in the Veterans Administration (VA) health care system. We evaluated anticoagulation prescription, INR monitoring intensity, and time in and outside INR therapeutic range (TTR) stratified by chronic kidney disease severity (CKD). Results Of 123,188 patients with newly diagnosed AF, use of warfarin decreased with increasing severity of CKD (57.2% to 46.4%), although it was higher among patients on dialysis (62.3%). Although INR monitoring intensity was similar across CKD strata, the proportion with TTR ≥ 60% decreased with CKD severity, with only 21% of patients on dialysis achieving TTR ≥ 60%. After multivariate adjustment, the magnitude of TTR reduction increased with CKD severity. Patients on dialysis had the highest time markedly out of range with INR <1.5 or INR >3.5 (30%); 12% of INR time was > 3.5, and low TTR persisted for up to three years. Conclusions There is a wide variation in anticoagulation prescription based on CKD severity. Patients with moderate to severe CKD, including dialysis, have substantially reduced TTR, despite comparable INR monitoring intensity. These findings have implications for more intensive warfarin management strategies in CKD or alternative therapies such as direct oral anticoagulants.

The treatment of AF has evolved over the past decade with increasing use of catheter ablation in patients refractory to medical therapy. While pulmonary vein isolation using endocardial catheter ablation has been successful in paroxysmal AF, the results have been more controversial in patients with long-standing persistent AF where extrapulmonary venous foci are increasingly recognised in the initiation and maintenance of AF. Hybrid ablation is the integration of minimally invasive epicardial ablation with endocardial catheter ablation, and has been increasingly used in this population with better results. The aim of this article was to analyse and discuss the evidence for the integration of catheter and minimally invasive surgical approaches to treat AF with specific focus on convergent ablation and exclusion of the left atrial appendage using a surgically applied clip.