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Background: Elective cardioversion (ECV) of atrial fibrillation (AF) is a standard procedure to restore sinus rhythm. However, predictors for ineffective ECV (failure of ECV or recurrence of AF within 30 days) are unknown.Methods: We investigated 1998 ECVs performed for AF lasting >48 h in 1,342 patients in a retrospective multi-center study. Follow-up data were collected from 30 days after ECV.Results: Median number of cardioversions was one per patient with a range of 1-10. Altogether 303/1998 (15.2%) ECVs failed. Long (>5 years) AF history and over 30 days duration of the index AF episode were independent predictors for ECV failure and low (<60/min) ventricular rate of AF predicted success of ECV. In patients with successful ECVs an early recurrence of AF was detected in 549 (32.4%) cases. Female gender, high (>60/min) ventricular rate, renal failure and antiarrhythmic agents at discharge were the independent predictors for recurrence. In total ECV was ineffective in 852 (42.6%) cases. Female gender (OR 1.44, CI95% 1.15-1.80, p < 0.01), young (<65 years) age (OR 1.31, CI95% 1.07-1.62, p = 0.01), ventricular rate >60/min (OR 1.92, CI95% 1.08-3.41, p = 0.03), antiarrhythmic medication at discharge (OR 1.48, CI95% 1.14-1.93, p < 0.01) and low (<60/ml/min) estimated glomerular filtration rate (OR 1.59, CI95% 1.08-2.33, p = 0.02) were predictors of ineffective ECV.Conclusions: Female gender, use of antiarrhythmic drug therapy and renal failure predicted both recurrence of AF and the composite end point. For the first time in a large real-life study several clinical predictors for clinically ineffective ECV were identified. [ABSTRACT FROM AUTHOR]

Determinants and inter-subject variations of fractal and complexity measures of R-R interval variability were studied in a random population of 200 healthy middle-aged women (age 51 [+ or -] 6 yr) and 189 men (age 50 [+ or -] 6 yr) during controlled conditions in the supine and sitting positions. The short-term fractal exponent ([[Alpha].sub.1]) was lower in women than men in both the supine (1.18 [+ or -] 0.20 vs. 1.12 [+ or -] 0.17, P [is less than] 0.01) and sitting position (P [is less than] 0.001). Approximate entropy (ApEn), a measure of complexity, was higher in women in the sitting position (1.16 [+ or -] 0.17 vs. 1.07 [+ or -] 0.19, P [is less than] 0.001), but no gender-related differences were observed in ApEn in the supine position. Fractal and complexity measures were not related to any other demographic, laboratory, or lifestyle factors. Intersubject variations in a fractal measure, [[Alpha].sub.1] (e.g., 1.15 [+ or -] 0.20 in the supine position, z value 1.24, not significant), and in a complexity measure, ApEn (e.g., 1.14 [+ or -] 0.18 in the supine position, z value 1.44, not significant), were generally smaller and more normally distributed than the variations in the traditional measures of heart rate variability (e.g., standard deviation of R-R intervals 49 [+ or -] 21 ms in the supine position, z value 2.53, P [is less than] 0.001). These results in a large random population sample show that healthy subjects express relatively little interindividual variation in the fractal and complexity measures of heart rate behavior and, unlike the traditional measures of heart rate variability, they are not related to lifestyle, metabolic, or demographic variables. However, subtle gender-related differences are also present in fractal and complexity measures of heart rate behavior. gender; heart rate variability; nonlinear methods; risk factors

Tulppo, Mikko P., Richard L. Hughson, Timo H. Makikallio, K. E. Juhani Airaksinen, Tapio Seppanen, and Heikki V. Huikuri. Effects of exercise and passive head-up tilt on fractal and complexity properties of heart rate dynamics. Am J Physiol Heart Circ Physiol 280: H1081-H1087, 2001.--tk;1Passive head-up tilt and exercise result in specific changes in the spectral characteristics of heart rate (HR) variability as a result of reduced vagal and enhanced sympathetic outflow. Recently analytic methods based on nonlinear system theory have been developed to characterize the nonlinear features in HR dynamics. This study was designed to assess the changes in the fractal and complexity measures of HR behavior during the passive head-up tilt and during exercise. Fractal exponent ([[Alpha].sub.1]) and approximate entropy (ApEn), measures of short-term correlation properties and overall complexity of HR, respectively, along with spectral components of HR variability were analyzed during a passive head-up tilt test (n = 10) and a low-intensity steady-state exercise (n = 20) in healthy subjects. We observed that [[Alpha].sub.1] increased during the tilt test (from 0.85 [+ or -] 0.22 to 1.48 [+ or -] 0.20; P [is less than] 0.001) and during the exercise (from 1.00 [+ or -] 0.22 to 1.37 [+ or -] 0. 14; P [is less than] 0.001). ApEn also increased during the exercise (from 1.04 [+ or -] 0.11 to 1. 11 [+ or -] 0.08; P [is less than] 0.05), but it did not change during the tilt test. The normalized high-frequency spectral component decreased and the low-frequency component increased similarly during both the exercise and the tilt test (P [is less than] 0.001 for all). Exercise and passive tilt result in an increase of short-term fractal correlation properties of HR dynamics, which is related to changes in the balance between the low- and high-frequency oscillations in controlled situations. Overall complexity of HR dynamics increases during exercise but not during passive tilt. variability; approximate entropy; detrended fluctuation analysis

Introduction:Severe warfarin overanticoagulation is a risk factor for bleeding, but there is little information on its manifestations, prognosis and factors affecting the outcome. We describe the manifestations and clinical outcomes of severe warfarin overanticoagulation in a large group of patients with atrial fibrillation (AF). Material and methods:All international normalized ratio (INR) samples (n = 961,431) in the Turku University Hospital region between 2003 and 2015 were screened. A total of 412 AF patients with INR ≥9 were compared to 405 patients with stable warfarin anticoagulation for AF. Electronic patient records were manually reviewed to collect comprehensive data. Results:Of the 412 patients with INR ≥9, bleeding was the primary manifestation in 105 (25.5%). Non-bleeding symptoms were recorded in 165 (40.0%) patients and 142 (34.5%) had no symptoms. A total of 17 (16.2%) patients with a bleed and 67 (21.8%) without bleeding died within 30 days after the event. Intracranial haemorrhage strongly predicted death within 30 days. Other significant predictors were non-bleeding symptoms, active malignancies, recent bleed, history of myocardial infarction, older age, renal dysfunction and a recent treatment episode. Conclusions:Bleeds are not the major determinant of the poor prognosis in severe overanticoagulation, as coincidental INR ≥9 findings also associate with high mortality.KEY MESSAGESOnly a quarter of AF patients with INR ≥9 suffered a bleeding event and the clinical manifestation of INR ≥9 had a significant impact on patient outcome.The 30-day mortality rate in patients with INR ≥9 was high ranging from 9.2 to 32.7%.Several significant predictors of 30-day mortality after INR ≥9 were identified. [ABSTRACT FROM PUBLISHER]

Background: Atrial fibrillation (AF) is often asymptomatic and undiagnosed until an ischaemic stroke occurs. An irregular pulse is a key manifestation of AF. We assessed whether pulse self-palpation is feasible in screening of AF.Methods: Altogether 205 residents of Lieto municipality aged ≥75 years were randomized in 2012 to receive brief education on pulse palpation focusing on evaluating rhythm regularity. Self-detected pulse irregularity and new AF diagnoses were recorded, and the subjects' quality of life and use of health care services were assessed during a three-year follow-up.Results: The subjects' median age was 78.2 [3.8] years, and 89 (43.4%) were men. Overall, 139 (68%) subjects had initial good motivation/capability for regular palpation. At four months, 112 (80.6%) subjects with good and 26 (39.4%) with inadequate motivation/capability palpated their pulse daily. At 12 months, 120 (58.5%) and at 36 months, 69 (33.7%) subjects palpated their pulse at least weekly. During the intervention, 67 (32.7%) subjects reported pulse irregularity. New AF was found in 10 (4.9%) subjects, 7 (70%) of whom had reported pulse irregularity. Pulse irregularity independently predicted new AF, but only one (0.5%) subject with new AF sought undelayed medical attention due to pulse irregularity. Quality of life and number of outpatient clinic visits remained unchanged during follow-up.Conclusion: Pulse palpation can be learned also by the elderly, but it is challenging to form a continuing habit. The low persistence of pulse self-palpation limits its value in the screening of AF, and strategies to promote persistence and research on alternative screening methods are needed.Trial Registration: http://www.ClinicalTrials.gov identifier: NCT01721005. The trial was registered retrospectively on October 26, 2012. [ABSTRACT FROM AUTHOR]

Background:Female sex, old age, and time to cardioversion increase the risk of thromboembolic complications (TEC) after cardioversion of atrial fibrillation (AF) < 48 h. The interaction of these variables is not known. We investigated the interaction of sex, age, and time to electrical cardioversion (ECV) on TEC in anticoagulant-naive patients with acute AF. Methods and results:The primary outcome was a TEC within 30 days following ECV. Patients were divided into three age groups and time to cardioversion into <12 h and ≥12 h in 4715 ECVs. TEC occurred in 40 (0.8%) patients. In multivariate analysis, female sex, time to ECV, and vascular disease were independent predictors of TEC. For patients ≤75 cardioverted within 12 h, the incidence of TEC was low. In patients >75 TEC increased in both sexes and particularly in women (1.4% vs. 0.9%, p = 0.03). When ECVs exceeded 12 h, the risk of TEC was two- to four-fold higher in women in all age groups. Conclusions:The risk of TEC increases substantially in patients >75 and ECVs ≥12 h, particularly in women. Time to cardioversion should be added to risk-stratification of ECVs of acute AF.Key messagesThe ideal timing of cardioversion is still unknown and not based on solid evidence. Delay to cardioversion ≥12 h should be added to the risk stratification of atrial fibrillation cardioversion.Female sex increases the risk of complications and failure of cardioversion after electrical cardioversion of atrial fibrillation <48 h, especially with age >75 years and time to cardioversion exceeding 12 h. [ABSTRACT FROM PUBLISHER]