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Background: Supraventricular extra beats (SVEB) are frequently observed in athletes but data on significance, prognostic role and correlation with cardiac remodeling are contrasting. It is uncertain whether SVEB may indicate the development of more complex arrhythmias and the need for closer monitoring is undetermined. The aim was to assess the prevalence and clinical significance of BESV in Olympic athletes of different sporting disciplines, evaluating potential correlations with cardiac remodeling and clinical features., Methods: We enrolled athletes who participated at 2012-2022 Olympic Games, submitted to physical examination, blood tests, echocardiography and exercise tests, categorized into power, skills, endurance and mixed disciplines., Results: We studied 1492 elite athletes: 56% male individuals, mean age 25.8 ± 5.1 years; 29.5% practiced power, 12.3% skills, 21% endurance and 37.2% mixed disciplines. At exercise-stress tests, 6.2% had SVEB, mostly single beats. SVEB were not influenced by anthropometrics or blood test results. They were more common in male individuals (77.4 vs. 54.6%, P < 0.0001) and older athletes (27.1 ± 5.7 vs. 25.7 ± 5.1, P = 0.01). In male athletes with SVEB, higher left atrial volumes were observed (24.2 ± 7.3 vs. 22.2 ± 7.1 ml/m2, P = 0.03). No differences were found in terms of sporting discipline: despite larger left atrial dimensions in aerobic disciplines, SVEB rates were similar in different sporting disciplines (6.1% endurance, 6.3% mixed, 5.2% power and 8.7% skills; P = 0.435)., Conclusion: SVEB were more common in older, male athletes and associated with higher left atrial volume (especially in male individuals) regardless of sport practiced. Athletes with greater left atrial volume and SVEB are supposed to have higher risk, in middle age, of developing more complex arrhythmias., (Copyright © 2024 Italian Federation of Cardiology - I.F.C. All rights reserved.)

Background: High blood pressure (BP) induces left atrial structural and functional remodeling that increases susceptibility to atrial arrhythmia. We hypothesized that lower systolic BP (SBP) levels are associated with a lower prevalence of premature atrial contractions (PACs) in patients with hypertension., Methods: This analysis included 4,697 participants (mean age 62±13.1 years, 50% women, 25.6% blacks) with hypertension from the Third National Health and Nutrition Examination Survey who did not have a prior history of cardiovascular disease (CVD). Multivariable logistic regression was used to examine the cross-sectional association between SBP and prevalence of PACs ascertained from 12-lead resting electrocardiograms. Multivariable Cox proportional hazard analysis was used to examine the association between baseline PACs and CVD mortality., Results: Approximately 1.6% (n=74) of participants had baseline PACs. Patients with SBP ≤140 mmHg had a lower prevalence of PACs than those with SBP ≥140 mmHg (1.1% vs. 1.9%, p-value=0.01). In a multivariable logistic regression model, each 10 mmHg decrease in SBP was associated with a 12% lower odds of PACs (OR (95%CI): 0.88 (0.77-0.99)). During 14 years of follow-up, 645 CVD deaths occurred. In a multivariable-adjusted Cox model, presence of PACs was associated with a 78% increased risk of CVD mortality (HR (95%CI): 1.78 (1.23-2.60))., Conclusions: In patients with hypertension, lower SBP levels are associated with a lower prevalence of PACs, and presence of PACs is associated with a higher risk of CVD mortality risk. These findings highlight the potential role of BP lowering in the management of cardiac arrhythmias., Competing Interests: Declaration of competing interest None declared., (Copyright © 2024 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.)

Purpose: This study aimed to investigate the proportion and risk factors of paroxysmal atrial fibrillation (AF) and atrial arrhythmias (AA) in patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in Vietnam., Patients and Methods: A prospective observational study was conducted at two major hospitals in Hanoi, Vietnam, from January 2022 to January 2023. A total of 197 AECOPD patients were recruited. ECG and 24-hour Holter ECG were used to diagnose paroxysmal AF and AA., Results: The prevalence of paroxysmal AF and AA were 15.2% and 72.6%, respectively. Factors associated with a higher likelihood of paroxysmal AF included aging 75 years old and above (aOR = 3.15; 95% CI: 1.28 to 8.48), Premature atrial complex (PAC) with 500 or more (aOR = 3.81; 95% CI: 1.48 to 10.97) and severity of COPD as group C and D (aOR = 3.41; 95% CI: 1.28 to 10.50). For AA, aging 75 years old and above (aOR = 2.25; 95% CI: 1.28 to 5.20), smoking (aOR = 2.10; 95% CI: 1.07 to 4.23) and P wave dispersion (PWD) with 40 milliseconds or more (aOR = 3.04; 95% CI: 1.54 to 6.19) were associated with a higher likelihood of AA., Conclusion: Overall, our findings highlight the associated factors with the paroxysmal AF and AA among AECOPD patients. This underscores the importance of a multifaceted approach to risk assessment and management in this vulnerable population, focusing not only on respiratory symptoms but also on comprehensive cardiovascular evaluation and intervention., Competing Interests: The authors report no conflicts of interest in this work., (© 2024 Nguyen et al.)

Background: Unknown cardioembolic sources are frequent causes of cryptogenic stroke. We analyzed the risk of atrial fibrillation (AF) or high burden of ectopic atrial activity (HBEA) in patients with cryptogenic stroke, assessing atrial function and 1-year outcomes., Methods and Results: The ARIES (Atrial Imaging and Cardiac Rhythm in Cryptogenic Embolic Stroke) study is an observational study including patients with cryptogenic stroke. We analyzed the frequency of AF and HBEA (>3000 atrial ectopic beats/day or >2 bursts or atrial tachycardia between 3 beats and ≤30 seconds) in two 30-day Holter-ECGs, comparing advanced echocardiography signs of left atrial (LA) dysfunction according to rhythm: AF, HBEA, and normal sinus rhythm. We also evaluated 1-year stroke recurrence and mortality. The study included 109 patients; 35 (32.1%) patients had AF, 27 (24.8%) HBEA, and 47 (43.1%) normal sinus rhythm. Compared with those with normal sinus rhythm, patients with AF presented higher 2-dimensional and 3-dimensional LA indexed volumes (38.8±11.2 versus 27.3±11.8 mL/m 2 , and 50.6±17.2 versus 34.0±15.4 mL/m 2 , respectively, P <0.001), lower 3-dimensional LA ejection fraction (50±14.6 versus 62.7±11.8, P =0.001), LA reservoir strain (22.0±8.6 versus 30.4±10.5, P <0.001), and LA contraction strain (10.5±8.18 versus 17.1±7.5, P <0.001), remaining significant in multivariate analysis. Patients with HBEA showed higher LA indexed volumes and lower LA reservoir strain than patients with normal sinus rhythm only in univariate analysis. There were no differences in ischemic recurrence or mortality among the groups., Conclusions: Patients with cryptogenic stroke showed a high incidence of AF and HBEA. AF is strongly related to LA volume, LA function, and LA reservoir and contraction strain, whereas HBEA showed milder structural changes. Advanced LA echocardiography could help patient selection for long-term ECG monitoring in suspected cardiac sources.

Background: The relationship between obstructive sleep apnea (OSA) and the occurrence of arrhythmias and heart rate variability (HRV) in hypertensive patients is not elucidated. Our study investigates the association between OSA, arrhythmias, and HRV in hypertensive patients., Methods: We conducted a cross-sectional analysis involving hypertensive patients divided based on their apnea-hypopnea index (AHI) into two groups: the AHI ≤ 15 and the AHI > 15. All participants underwent polysomnography (PSG), 24-hour dynamic electrocardiography (DCG), cardiac Doppler ultrasound, and other relevant evaluations., Results: The AHI > 15 group showed a significantly higher prevalence of frequent atrial premature beats and atrial tachycardia (P = 0.030 and P = 0.035, respectively) than the AHI ≤ 15 group. Time-domain analysis indicated that the standard deviation of normal-to-normal R-R intervals (SDNN) and the standard deviation of every 5-minute normal-to-normal R-R intervals (SDANN) were significantly higher in the AHI > 15 group (P = 0.020 and P = 0.033, respectively). Frequency domain analysis revealed that the low-frequency (LF), high-frequency (HF) components, and the LF/HF ratio were also significantly elevated in the AHI > 15 group (P < 0.001, P = 0.031, and P = 0.028, respectively). Furthermore, left atrial diameter (LAD) was significantly larger in the AHI > 15 group (P < 0.001). Both univariate and multivariable linear regression analyses confirmed a significant association between PSG-derived independent variables and the dependent HRV parameters SDNN, LF, and LF/HF ratio (F = 8.929, P < 0.001; F = 14.832, P < 0.001; F = 5.917, P = 0.016, respectively)., Conclusions: Hypertensive patients with AHI > 15 are at an increased risk for atrial arrhythmias and left atrial dilation, with HRV significantly correlating with OSA severity., (© 2024. The Author(s).)

Objectives: Fetal premature atrial contractions (PAC) are usually benign but may be associated with congenital heart defect (CHD) and tachyarrhythmia, which in turn carry a risk of cardiac failure and fetal death. We aimed to explore the frequency of adverse outcome and to identify risk factors for tachyarrhythmia in pregnancies complicated by fetal PAC., Methods: This was a retrospective cohort study of fetuses diagnosed with PAC at two academic centers in Amsterdam, The Netherlands, between 2007 and 2022. Cases with a congenital anomaly and those with a prior diagnosis of CHD or other arrhythmias were excluded. M-mode and Doppler tracings were reanalyzed and the frequency of PAC was recorded. The incidence of the following adverse outcomes was examined: underlying CHD not identified at the 20-week fetal anomaly scan, tachyarrhythmia, other arrhythmia, administration of antiarrhythmic therapy and death. Risk factors for tachyarrhythmia were analyzed using odds ratios (OR)., Results: In 24.1% of 1439 referred cases, PAC resolved before confirmation at the fetal medicine unit (FMU). Of the 939 included cases with confirmed PAC, the total incidence of adverse outcome was 6.8% (64/939). CHD was diagnosed in 14 (1.5% (95% CI, 0.9-2.5%)) cases, of which eight were diagnosed prenatally and six postnatally. Compared with baseline, the incidence of CHD was higher in the presence of fetal PAC (OR, 1.8 (95% CI, 1.0-3.3); P = 0.034). Tachyarrhythmia occurred prenatally and/or postnatally in 32 (3.4%) cases, of which eight (25.0%) showed signs of cardiac failure, and in 23 (71.9%) cases, antiarrhythmic therapy was required. No cases of tachyarrhythmia led to fetal or infant death. Risk factors for tachyarrhythmia were PAC with short runs of supraventricular tachycardia (OR, 98.7), blocked PAC (OR, 30.3), PAC in bigeminy (OR, 21.8), frequent PAC (one per 5-10 beats) (OR, 6.9), signs of cardiac failure (OR, 14.2) and the presence of a foramen ovale aneurysm (OR, 5.0)., Conclusions: PAC are generally benign and often resolve spontaneously. However, fetuses with an irregular heart rhythm should be referred for advanced ultrasonography, which should focus on classifying the type of PAC and risk of adverse outcome. When risk factors for tachyarrhythmia are identified, weekly fetal heart-rate monitoring is advised until resolution of the PAC. In the absence of risk factors, standard obstetric care may be sufficient, with additional instructions to report reduced fetal movements. Should tachyarrhythmia or cardiac failure develop, referral back to the FMU is indicated. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology., (© 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.)

Background: Covert atrial fibrillation (AF) is a major cause of cryptogenic stroke. This study investigated whether a dose-dependent relationship exists between the frequency of premature atrial contractions (PACs) and AF detection in patients with cryptogenic stroke using an insertable cardiac monitor (ICM)., Methods: We enrolled consecutive patients with cryptogenic stroke who underwent ICM implantation between October 2016 and September 2020 at 8 stroke centers in Japan. Patients were divided into 3 groups according to the PAC count on 24-hour Holter ECG: ≤200 (group L), >200 to ≤500 (group M), and >500 (group H). We defined a high AF burden as above the median of the cumulative duration of AF episodes during the entire monitoring period. We evaluated the association of the frequency of PACs with AF detection using log-rank trend test and Cox proportional hazard model and with high AF burden using logistic regression model, adjusting for age, sex, CHADS 2 score., Results: Of 417 patients, we analyzed 381 patients with Holter ECG and ICM data. The median age was 70 (interquartile range, 59.5-76.5), 246 patients (65%) were males, and the median duration of ICM recording was 605 days (interquartile range, 397-827 days). The rate of new AF detected by ICM was higher in groups with more frequent PAC (15.5%/y in group L [n=277] versus 44.0%/y in group M [n=42] versus 71.4%/y in group H [n=62]; log-rank trend P <0.01). Compared with group L, the adjusted hazard ratios for AF detection in groups M and H were 2.11 (95% CI, 1.24-3.58) and 3.23 (95% CI, 2.07-5.04), respectively, and the adjusted odds ratio for high AF burden in groups M and H were 2.57 (95% CI, 1.14-5.74) and 4.25 (2.14-8.47), respectively., Conclusions: The frequency of PACs was dose-dependently associated with AF detection in patients with cryptogenic stroke., Competing Interests: Disclosures Dr Todo reports lecture fees from Pfizer, Bristol-Myers Squibb, Daiichi-Sankyo, Bayer, Medtronic, Abbott, and Otsuka Pharmaceutical. Dr Doijiri reports lecture fees from Medtronic, Abbott, Biotronic, Daiichi Sankyo, Bristol-Myers Squibb, and Bayer. Dr Yamazaki reports lecture fees from Medtronic, Abbott, Daiichi Sankyo, Bristol-Myers Squibb, and Bayer. Dr Iwata reports lecture fees from Daiichi-Sankyo, and Medtronic. Dr Sonoda reports lecture fees from Medtronic, Abbott, and Daiichi-Sankyo. Dr Koge reports lecture fees from Medtronic. Dr Koga reports honoraria from Daiichi-Sankyo and research support from Daiichi-Sankyo. Dr Nagata reports lecture fees from Otsuka Pharmaceutical, Daiichi-Sankyo, Eli Lilly, and Amgen. Dr Ueno reports research funds from Bristol-Myers Squibb. Dr Yamagami reports lecture fees from Medtronic, Abbott, Daiichi-Sankyo, Bristol-Myers Squibb, and Bayer, and grant support from Bristol-Myers Squibb. Dr Gon reports lecture fees from Eisai, Kyowa Kirin, and Pfizer. The other authors report no conflicts.

Although increased premature atrial contractions (PACs) reportedly predict atrial fibrillation (AF) in both general and specific (e.g., patients with stroke) populations, early postoperative AF (POAF) risk in patients with increased PAC burden who require cardiac surgery remains unclear. We examined the correlation between different preoperative PAC burdens and POAF in patients with obstructive hypertrophic cardiomyopathy (OHCM) who underwent surgical treatment. We analyzed 304 consecutively admitted patients with OHCM without previous AF who underwent isolated septal myectomy between January 2015 and December 2018. All patients underwent preoperative 24-hour Holter electrocardiogram monitoring. PACs were present in 259 patients (85.20%) and absent in 45 patients (14.80%). According to the cut-off PAC number of 100 beats/24 hours, there were 211 patients (69.41%) with low-burden PACs and 48 patients (15.79%) with high-burden PACs. AF after septal myectomy occurred in 73 patients, which consisted of 3/45 in the non-PAC group (6.67%), 47/211 in the low-PAC-burden group (22.27%), and 23/48 in the high PAC burden group (47.92%). POAF incidence was higher in both low- and high-burden patients than in patients without PAC (p <0.01). Multivariate logistic regression analyses demonstrated that high-burden PACs (p = 0.02) and age (p <0.01) but not low-burden PACs (p = 0.22) independently predicted POAF in patients with OHCM. The area under the receiver operating characteristic curve for preoperative PACs was 0.72 (95% confidence interval 0.66 to 0.79, p <0.01, sensitivity: 68.49%, specificity: 69.26%). In conclusion, POAF incidence was significantly higher in patients with preoperative high-burden PACs and can predict POAF in patients with OHCM., Competing Interests: Disclosures The authors have no conflicts of interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Premature atrial contractions are a common cardiac phenomenon. Although previously considered a benign electrocardiographic finding, they have now been associated with a higher risk of incident atrial fibrillation (AF) and other adverse outcomes such as stroke and all-cause mortality. Since premature atrial contractions can be associated with these adverse clinical outcomes independently of AF occurrence, different explanations have being proposed. The concept of atrial cardiomyopathy, where AF would be an epiphenomenon outside the causal pathway between premature atrial contractions and stroke has received traction recently. This concept suggests that structural, functional, and biochemical changes in the atria lead to arrhythmia occurrence and thromboembolic events. Some consensus about diagnosis and treatment of this condition have been published, but this is based on scarce evidence, highlighting the need for a clear definition of excessive premature atrial contractions and for prospective studies regarding antiarrhythmic therapies, anticoagulation or molecular targets in this group of patients., Competing Interests: Conflict of interest: J.M.F.: none declared; D.G.: institutional research grants from Boston Scientific, Medtronic and Biosense Webster, and personal advisory fees from Boehringer Ingelheim, Boston Scientific and Abbott; G.Y.H.L.: consultant and speaker for BMS/Pfizer, Boehringer Ingelheim and Daiichi-Sankyo. No fees are received personally., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Objectives: Although evidence has shown the association of excessive supraventricular ectopic activity (ESVEA) with future development of atrial fibrillation (AF), this relationship is not yet fully understood. This study examines whether ESVEA can predict the future onset of AF, in patients presenting with cryptogenic stroke., Materials and Methods: A retrospective cohort of 124 non-AF, consecutive patients, hospitalized for cryptogenic stroke between 2014 and 2015, was retrieved. 24-h inpatient monitoring with Holter was employed to reveal ESVEA, defined as the presence of more than 20 premature atrial complexes per hour (PACs/h) on average, or a more than 5 s duration of the longest supraventricular run (LSVR). After a median follow-up period of 5.2 years, the patients were examined for AF., Results: From initial 124 patients, 12 died and one was lost during follow-up. For the total of 111 patients finally included, the median age was 56 years and 25.2% were females. The overall baseline median CHA2DS2-VASc score was 3. AF was found in 13 (11.71%) patients. Patients who were finally diagnosed with AF had a significantly higher number of PACs/h and a longer median LSVR duration at baseline (16.67 vs. 0.21, p < 0.001 and 3 vs. 0 s, p < 0.001, respectively). The presence of ESVEA was also significantly more frequent among AF patients (46.15%, 95%CI: 17.78%-74.22%) compared to non-AF ones (6.1%, 95%CI: 1.3%-10.7%, p < 0.001)., Conclusions: Excessive atrial ectopy, detected with 24 h inpatient Holter monitoring, is a significant indicator of future development of AF in patients presenting originally with a cryptogenic stroke., Competing Interests: Declaration of Competing Interest None., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Fetal heart-rate irregularities occur in 1-2% of pregnancies and are usually caused by premature atrial contractions (PAC). Although PAC are considered benign, they may be associated with cardiac defects and tachyarrhythmia. We aimed to determine the incidence of congenital heart defects (CHDs) and complications in fetuses with PAC., Methods: This was a systematic review and meta-analysis conducted in accordance with the PRISMA statement for reporting items for systematic reviews and meta-analyses. MEDLINE and EMBASE were searched from 1990 to June 2021 to identify studies on fetuses with PAC. The primary outcome was CHD; secondary outcomes were complications using the endpoints supraventricular tachyarrhythmia (SVT), cardiac failure and intrauterine fetal demise. Meta-analysis of proportions was performed, subdivided into high-risk and low-risk populations based on reason for referral. Pooled incidences with 95% CIs were calculated., Results: Of 2443 unique articles identified, 19 cohort studies including 2260 fetuses were included. The pooled incidence of CHD in fetuses with PAC was 2.8% (95% CI, 1.5-4.1%), when 0.6% is the incidence expected in the general population. The pooled incidence of CHD was 7.2% (95% CI, 3.5-10.9%) in the high-risk population and 0.9% (95% CI, 0.0-2.0%) in the low-risk population. SVT occurred in 1.4% (95% CI, 0.6-3.4%) of fetuses diagnosed with PAC. Cardiac failure was described in 16 fetuses (1.4% (95% CI, 0.5-3.5%)), of which eight were CHD-related. Intrauterine fetal demise occurred in four fetuses (0.9% (95% CI, 0.5-1.7%)) and was related to CHD in two cases., Conclusions: Our findings suggest that the risk of CHD in fetuses with PAC is 4-5 times higher than that in the general population. CHD was present more frequently in the high-risk population. Consequently, an advanced ultrasound examination to diagnose PAC correctly and exclude CHD is recommended. Complications of PAC are rare but can result in fetal demise, thus weekly fetal heart-rate monitoring remains advisable to enable early detection of SVT and to prevent cardiac failure. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology., (© 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.)

Background Fine particulate (fine particles with aerodynamic diameters ≤2.5 μm [PM 2.5 ]) exposure has been associated with a risk of cardiac arrhythmias in adults. However, the association between PM 2.5 exposure and cardiac arrhythmias in adolescents remains unclear. Methods and Results To investigate the association and time course between PM 2.5 exposure with cardiac arrhythmias in adolescents, we analyzed the data collected from 322 adolescents who participated in the PSCC (Penn State Child Cohort) follow-up examination. We obtained individual-level 24-hour PM 2.5 concentrations with a nephelometer. Concurrent with the PM 2.5 measure, we obtained 24-hour ECG data using a Holter monitor, from which cardiac arrhythmias, including premature atrial contractions and premature ventricular contractions (PVCs), were identified. PM 2.5 concentration and numbers of premature atrial contractions/PVCs were summarized into 30-minute-based segments. Polynomial distributed lag models within a framework of a negative binomial model were used to assess the effect of PM 2.5 concentration on numbers of premature atrial contractions and PVCs. PM 2.5 exposure was associated with an acute increase in number of PVCs. Specifically, a 10 μg/m 3 increase in PM 2.5 concentration was associated with a 2% (95% CI, 0.4%-3.3%) increase in PVC counts 0.5 to 1.0, 1.0 to 1.5, and 1.5 to 2.0 hours after the exposure. Cumulatively, a 10 μg/m 3 increment in PM 2.5 was associated with a 5% (95% CI, 1%-10%) increase in PVC counts within 2 hours after exposure. PM 2.5 concentration was not associated with premature atrial contraction. Conclusions PM 2.5 exposure was associated with an acute increased number of ventricular arrhythmias in a population-based sample of adolescents. The time course of the effect of PM 2.5 on ventricular arrhythmia is within 2 hours after exposure.

Background: Premature atrial contractions (PACs) are predictors of atrial fibrillation, stroke, and cardiovascular mortality. The present study aimed to assess relevant factors for PACs among a general population of Japanese men., Methods and results: This study conducted a population-based, cross-sectional study among 517 men, aged 40-79 years, with neither apparent myocardial infarction nor atrial fibrillation. 24-h Holter electrocardiography to assess PAC frequency was used. Age, body mass index, height, low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein cholesterol, mean heart rate, diabetes mellitus, hypertension, physical activity, smoking, alcohol consumption, and lipid-lowering therapy were included in multivariable negative binomial regression analyses to assess correlation for the number of PACs per hour. Almost all participants (99%) had at least 1 PAC in 1 h (median number 2.84 PACs per h). In multivariable negative binomial regression after adjusting for all covariates simultaneously, age (relative risk [95% confidence interval], 1.30 [1.08-1.57] per 1-standard deviation [SD] increment), height (1.19 [1.02-1.39] per 1-SD increment), triglycerides (0.79 [0.65-0.97] per 1-SD increment), mean heart rate (0.69 [0.59-0.80] per 1-SD increment), physical activity (0.63 [0.43-0.93]), current smoking (1.69 [1.06-2.69]), current moderate (1.97 [1.23-3.16]) and heavy (1.84 [1.12-3.01]) alcohol consumption were independently associated with PAC frequency., Conclusions: PAC frequency was independently associated with age, height, smoking, alcohol consumption, heart rate, physical activity, and triglycerides.

Background Black Americans have more atrial fibrillation risk factors but lower atrial fibrillation risk than White Americans. Left atrial (LA) enlargement and/or dysfunction, frequent atrial tachycardia (AT), and premature atrial contractions (PAC) are associated with increased atrial fibrillation risk. Racial differences in these factors may exist that could explain the difference in atrial fibrillation risk. Methods and Results We included 2133 ARIC (Atherosclerosis Risk in Communities) study participants (aged 74±4.5 years[mean±SD], 59% women, 27% Black participants) who had echocardiograms in 2011 to 2013 and wore the Zio XT Patch (a 2-week continuous heart monitor) in 2016 to 2017. Linear regression was used to analyze (1) differences in AT/day or PAC/hour between Black and White participants, (2) differences in LA measures between Black and White participants, and (3) racial differences in the association of LA measures with AT or PAC frequency. Compared with White participants, Black participants had a higher prevalence of cardiovascular risk factors and disease, lower AT frequency, greater LA size, and lower LA function. After multivariable adjustments, Black participants had 37% (95% CI, 24%-47%) fewer AT runs/day than White participants. No difference in PAC between races was noted. Greater LA size and reduced LA function are associated with more AT and PAC runs; however, no race interaction was present. Conclusions Differences in LA measures are unlikely to explain the difference in atrial fibrillation risk between Black and White individuals. Despite more cardiovascular risk factors and greater atrial remodeling, Black participants have lower AT frequency than White participants. Future research is needed to elucidate the protective mechanisms that confer resilience to atrial arrhythmias in Black individuals.

The aim of this study was to establish the prevalence and prognostic implication of progressive supraventricular arrhythmias from frequent supraventricular ectopic complexes, isolated, in bi- or trigeminy, to supraventricular tachycardias with different characteristics. In the STROKESTOP I mass-screening study for atrial fibrillation (AF) in 75- and 76-year olds in Sweden, participants registered 30-second intermittent ECG twice daily for two weeks. The ECG-recordings from STROKESTOP I were re-evaluated using an automated algorithm to detect individuals with frequent supraventricular ectopic complexes or runs. Detected episodes were manually re-examined to confirm the findings. The primary endpoint was AF as ascertained from the national Swedish Patient register. Exploratory secondary endpoints were stroke and death. Median follow-up was 4.2 (interquartile range [IQR] 3.8-4.4) years. Of the examined 6,100 participants, 85% were free of significant supraventricular arrhythmia. In the 894 participants that had arrhythmia, frequent supraventricular ectopic complexes were the most common arrhythmia, n = 709 (11.6%) and irregular supraventricular tachycardias were more common than regular. Individuals with the most AF similar supraventricular tachycardias, irregular and lacking p-waves (termed micro-AF), n = 97 (1.6%) had the highest risk of developing AF (hazard ratio 4.3; 95% confidence interval [CI] 2.7-6.8). They also had increased risk of death (hazard ratio 2.0; CI 1.1-3.8). In conclusion, progression of atrial arrhythmias from supraventricular ectopic complexes to more AF-like episodes is associated with development of AF. Extended screening for AF should be considered in individuals with frequent supraventricular activity, especially in those with supraventricular tachycardias with AF characteristics., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Premature atrial contractions (PACs) are associated with increased risk of atrial fibrillation (AF) and ischemic stroke. Although lifestyle and risk factor modification reduces AF incidence, their relationship to PACs frequency is unclear. We assessed the association of Life's Simple 7 (LS7) and individual LS7 factors in midlife with PACs frequency in late life in the Atherosclerosis Risk in Communities (ARIC) Study., Methods: We followed 1924 participants from ARIC clinic Visit 3 (1993--95) to Visit 6 (2016-17) when a 2-week continuous heart rhythm monitor (Zio®XT Patch) was applied. LS7 factors were assessed at Visit 3 and a composite score was calculated. PACs frequency was categorized as minimal (<0.1%), occasional (≥0.1%-5%) and frequent (>5%). Logistic regression was used to evaluate the association of LS7 score and individual factors with PACs frequency., Results: Each 1-point LS7 score increase was associated with lower odds of frequent PACs vs. no PACs (OR [95% CI]: 0.87 [0.78, 0.98]) and frequent PACs vs. occasional PACs (OR [95% CI]: 0.88 [0.79, 0.98]). Of the individual LS7 factors, compared with ideal physical activity, poor physical activity was associated with 81% higher odds of frequent PACs vs. no PACs. Compared with ideal BMI, poor BMI was associated with 41% higher odds of occasional PACs vs. no PACs., Conclusion: Lifestyle risk factors, particularly physical activity and BMI, are associated with higher odds of PACs frequency. More research is needed to determine whether modifying these risk factors in midlife would prevent frequent PACs, and thereby prevent AF and stroke in older age., Competing Interests: Declaration of Competing Interest There are no conflicts of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Various predictors of atrial fibrillation (AF) recurrence have been shown based on the baseline characteristics before catheter ablation (CA). This study aimed to develop a novel scoring system for predicting very late recurrences of AF (VLRAFs) after an initial CA, taking the postprocedural clinical data into account and reassessing VLRAFs in 12-month patients' condition using previously known preprocedural predictors of AF recurrences. We retrospectively studied 327 patients who underwent an initial CA with freedom from AF for over 12 months. We elucidated the predictors of VLRAFs and created a new score to predict VLRAFs in the discovery AF cohort (n = 181). Thereafter, we investigated whether the new scoring system could accurately predict VLRAFs in the validation AF cohort (n = 146). In the discovery AF cohort, VLRAFs were observed in 53 patients (29%) during the follow-up period (mean follow-up duration: 55 months). The univariate and multivariate Cox proportional-hazards model demonstrated that non-pulmonary vein foci, early recurrences of AF (ERAFs), atrial premature contraction (APC) burden ≥ 142/24 hours, and minimum prematurity index of the APCs ≤ 48% were associated with VLRAFs after CA. We created a new scoring system to predict VLRAFs, the n-PReDCt score (non-pulmonary vein: 1 point, early recurrences of AFs (Recurrences of AF in early phase after CA): 1 point, APC burden ≥ 142/24 hours: 1 point, and minimum prematurity index (= Coupling interval) of the APCs of ≤ 48%: 1 point). The n-PReDCt score was significantly associated with VLRAFs by a Kaplan-Meier analysis in the discovery AF and validation AF cohorts (p < 0.0001 and p < 0.0001, respectively)., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The prevalence and severity of cardiac arrhythmias in healthy racehorses undergoing competition is not well defined. The aim was to characterize arrhythmias in Thoroughbreds participating in official Chuckwagon races and to determine normal beat-to-beat (R-R) variability during supramaximal exercise. Electrocardiograph (ECG) recordings were obtained during pre-race, race, and active-recovery from 82 clinically healthy Thoroughbreds. ECG recordings were analyzed for arrhythmias and mean percent R-R deviation. Plasma lactate and high-sensitivity troponin (hs-cTnT) were also measured. Fifty-two ECGs were included in the analysis. Arrhythmias were seen in 48/52 horses (92%) and were predominantly isolated events. No complex rhythms were observed. During the race, 92% of horses had arrhythmias (81% supraventricular premature complex [SVPC]; 33% ventricular premature complex [VPC]). Eleven percent of racing arrhythmias were VPCs (all singlets except for two couplets). During active-recovery, 58% of horses had arrhythmias (56% SVPC; 15% VPCs): Three horses had VPC couplets and one horse had a VPC triplet. All plasma hs-cTnT were within normal limits. The measured lactate was 28.5 ± 4.5 mmol/L, confirming supramaximal exercise. R-R variation ranged between -9.5 to +18.8% during pre-race (mean heart rate [HR], 155 ± 22 beats per min [bpm]), -27.8 to +45.3% during racing (mean HR, 200 ± 9 bpm) and -16.4 to +40.1% during active-recovery (mean HR, 165 ± 14 bpm). Maximal and 1st percentile R-R shortening and lengthening were significantly greater at race than pre-race and active-recovery (P < 0.0001). Racing and active-recovery maximal R-R lengthening were significantly greater than pre-race (P = 0.0003). Supraventricular premature complexes and VPCs are prevalent in healthy horses undergoing Chuckwagon racing. R-R variation is greater during racing than has previously been described., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The Chiari network (CN) is a mobile, net-like structure occasionally present in the right atrium, near the opening of the inferior vena cava and coronary sinus. While typically asymptomatic, it may contribute to thromboembolism or right atrial pathologies. Here, we hypothesized that existing differences in P-wave morphology on electrocardiograms (ECG) may be associated with atrial conduction changes. Seventy-one children with a CN were recruited and matched to 60 healthy controls. P-wave duration, P-wave amplitude, P dispersion (Pd), QRS, PR, QT, and QTc (calculated with Bazett formula) intervals were measured and compared. Between the control and the patient groups, the mean P-wave duration was 78.1 ms and 88.7 ms, P amplitude was 1.3 mm and 1.1 mm, and Pd was 18.9 and 35.5 ms, respectively. These differences were statistically significant across all measurements (p < 0.05). Atrial conduction may be affected in patients with CN, and these patients may then develop atrial arrhythmia.

Objective: To examine the association between polarity of atrial premature complexes (APCs) and stroke., Design: A prospective study., Setting and Participants: A total of 11 092 participants in the Jichi Medical School cohort study were included after excluding patients with atrial fibrillation. We analysed stroke events in patients with (n=136) and without (n=10 956) APCs. With regard to polarity of APCs, patients were subcategorised into having (1) negative (n=39) or non-negative (n=97) P waves in augmented vector right (aVR), and (2) positive (n=28) or non-positive (n=108) P waves in augmented vector left (aVL)., Outcome Measures: The primary endpoint was stroke., Results: Patients with APCs were significantly older than those without APCs (64.1±9.2 vs 55.1±11.6 years, p<0.001). The mean follow-up period was 11.8±2.4 years. Stroke events were observed in patients with (n=13 events) and without (n=411 events) APCs. This difference was significant (log-rank 12.9, p<0.001); however, APCs were not an independent predictor of stroke after adjusting for age, sex, height, body mass index, current drinking, diabetes, systolic blood pressure, prior myocardial infarction, prior stroke and high-density lipoprotein-cholesterol (p=0.15). The incidence of stroke in patients with APCs and non-negative P wave in aVR was significantly higher than in patients without APCs (log-rank 20.1, p<0.001), and non-negative P wave in aVR was revealed to be an independent predictor of stroke (HR 1.84, 95% CI 1.02 to 3.30). The incidence of stroke in patients with APC with non-positive P wave in aVL was also significantly higher than in patients without APC (log-rank 15.3, p<0.001), and non-positive P wave in aVL was an independent predictor of stroke (HR 1.92, 95% CI 1.05 to 3.54)., Conclusions: The presence of APCs with non-negative P wave in aVR or non-positive P wave in aVL on 12-lead ECG was associated with a higher risk of incident stroke., Competing Interests: Competing interests: TK has received scholarship funding from Mitsubishi Tanabe Pharma. KK has received research grants from A&D, Omron Healthcare, Roche Diagnostics KK, MSD KK, Astellas Pharma, Otsuka Holdings, Otsuka Pharmaceutical, Sanofi KK, Shionogi & Co, Sanwa Kagaku Kenkyusho, Daiichi Sankyo, Sumitomo Dainippon Pharma, Takeda Pharmaceutical, Mitsubishi Tanabe Pharma, Teijin Pharma, Boehringer Ingelheim Japan, Pfizer Japan and Fukuda Denshi., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: Opioids, gabapentinoids, and nonsteroidal anti-inflammatory drugs (NSAIDs) may have adverse cardiovascular effects. We evaluated whether these medications were associated with incident clinically detected atrial fibrillation (AF) or monitor-detected supraventricular ectopy (SVE), including premature atrial contractions (PACs) and supraventricular tachycardia (SVT)., Methods: We used data from the Multi-Ethnic Study of Atherosclerosis (MESA), a cohort study that enrolled 6814 Americans without clinically detected cardiovascular disease in 2000 to 2002. At the 2016 to 2018 examination, 1557 individuals received ambulatory electrocardiographic (ECG) monitoring. Longitudinal analyses investigated time-varying medication exposures at the first five exams (through 2011) in relation to incident clinically detected AF through 2015 using Cox proportional hazards regression models. Cross-sectional analyses investigated medication exposures at 2016 to 2018 examination and the risk of monitor-detected SVE using linear regression models., Results: The longitudinal cohort included 6652 participants. During 12.4 years of mean follow-up, 982 participants (14.7%) experienced incident clinically detected AF. Use of opioids, gabapentinoids, and NSAIDs were not associated with incident AF. The cross-sectional analysis included 1435 participants with ECG monitoring. Gabapentinoid use was associated with an 84% greater average frequency of PACs/hour (95% CI, 25%-171%) and a 44% greater average number of runs of SVT/day (95% CI, 3%-100%). No associations were found with use of opioids or NSAIDs in cross-sectional analyses., Conclusions: In this study, gabapentinoid use was associated with SVE. Given the rapid increase in gabapentinoid use, additional studies are needed to clarify whether these medications cause cardiovascular complications., (© 2020 John Wiley & Sons Ltd.)

Background: Whether ectopic atrial rhythm (EAR) is a high-risk cardiovascular phenotype (eg, the manifestation of a diseased sinoatrial node) or just a benign accelerated ectopic pacemaker remains unclear., Objective: We aimed to analyze the cardiovascular outcomes and underlying mechanisms in patients with EAR., Methods: From a 12-lead electrocardiogram hospital-based electrocardiogram database, a total of 2896 adults with EAR were propensity score matched at 1:5 with 14,480 patients with sinus rhythm (SR). Patients were retrospectively followed up for cardiovascular mortality (the primary outcome) and permanent pacemaker implantation (the secondary outcome). Heart rate variability was analyzed to compare autonomic function between patients with EAR and those with SR., Results: The prevalence of EAR was 1.13%, which increased with age. Compared with the matched patients, those with EAR had a higher risk of cardiovascular mortality (adjusted hazard ratio 1.93; 95% confidence interval 1.52-2.44; P < .0001) and permanent pacemaker implantation (adjusted hazard ratio 5.94; 95% confidence interval 3.89-9.09; P < .0001) according to the Cox proportional hazards regression model. The risk of cardiovascular mortality was similar across the subgroups on the basis of age, sex, hypertension, type 2 diabetes mellitus, congestive heart failure, myocardial infarction, stroke, and chronic kidney diseases. In patients with EAR, the low frequency/high frequency and standard deviation of the mean normal-to-normal intervals/root mean square of successive RR interval differences ratios for heart rate variability were both lower than those in patients with SR. This implied autonomic imbalance in patients with EAR., Conclusion: Patients with EAR have a higher risk of cardiovascular mortality and permanent pacemaker implantation, which was associated with autonomic imbalance., (Copyright © 2020. Published by Elsevier Inc.)

The relationship between atrial fibrillation (AF) type and stroke risk is still controversial. We investigated the difference of burden of atrial ectopic beats in different types of AF and the effect of the AF type on stroke risk in patients with non-valvular AF. In the prospective, multicenter observational registry with more than about 10,000 AF patients, 8883 non-valvular AF patients (mean age, 67.0 years; 36% were women) with eligible follow-up visits participated. We compared the burden of ectopic beats and stroke risk between patients with paroxysmal AF (n = 5,808) and non-paroxysmal AF (n = 3,075). The patients with a non-paroxysmal type of AF were older, male-predominant and had a higher prevalence of comorbidities and had more anticoagulation and rhythm control treatment than those with paroxysmal AF. In terms of the difference in burden of ectopic beats, patients with non-paroxysmal AF had a higher proportion of atrial premature beats (APBs) (paroxysmal vs. non-paroxysmal, median 3% vs. 5%; p = 0.001) in 24 hours Holter monitoring. During a median follow-up period of 16.8 months (Interquartile range [IQR], 11.67-20.52), a total of 82 (0.92%) patients experienced ischemic stroke with incidence rates of 0.50 and 1.09 events per 100 person-year for paroxysmal and non-paroxysmal AF, respectively. The cumulative incidence of stroke events was significantly higher in non-paroxysmal AF than in paroxysmal AF (p < 0.001). The risk of ischemic stroke was higher in non-paroxysmal AF with an adjusted hazard ratio (HR) of 2.08 (95% confidence interval [CI], 1.33-3.25; p = 0.001) than in paroxysmal AF. The type of AF was associated with an increased risk of stroke, along with the difference of burden of ectopic beats (specially in APBs) in different types of AF. These results suggest that the type of AF should be considered in stroke prevention and decision-making for oral anticoagulation in AF patients.

Background: Short supraventricular tachycardias with atrial fibrillation (AF) characteristics are associated with an increased risk of developing AF over time. The aim of this study is to determine if presence of very short-lasting episodes of AF-like activity (micro-AF) can also be used as a marker of undiagnosed silent atrial fibrillation., Methods: In the STROKESTOP II study, a Swedish mass screening study for AF among 75- and 76-year-olds, participants with NT-proBNP ≥125 ng/L performed intermittent ECG recordings 30 s, four times daily for 2 weeks. Participants with micro-AF (sudden onset of irregular tachycardia with episodes of ≥5 consecutive supraventricular beats and total absence of p-waves, lasting less than 30 s) were invited to undergo extended AF screening using continuous event recording for 2 weeks. A control group of individuals without micro-AF was examined using the same ECG modalities., Results: Out of 3763 participants in STROKESTOP II who had elevated NT-proBNP levels and were free of AF, n = 221 (6%) had micro-AF. The majority of participants with micro-AF (n = 196) accepted further investigation with continuous ECG monitoring which showed presence of AF in 26 of them. In the control group (n = 250), continuous monitoring detected 7 new AF cases. Thus, AF was significantly more common in the micro AF group (13%) compared to the control group (3%), p < 0.001., Conclusions: Presence of short-lasting episodes of AF-like activity (micro-AF) indicates increased likelihood for undetected AF. Continuous screening therefore seems recommendable if a finding of AF would change clinical management., Trail Registration: ClinicalTrials.gov, identifier: NCT02743416, registered April 19, 2016.

Background: Low resting heart rate and premature atrial contractions (PACs) predict incident atrial fibrillation (AF) and could be interdependent, since PACs occur in the gaps between normal beats., Objective: To study the association between low heart rate at 24hECG, PACs and incident AF in a prospective population-based cohort., Methods: In the Malmö Diet and Cancer study, 24hECGs were performed in 377 AF-free subjects. The endpoint was clinical AF retrieved from national hospital (mean follow-up 17 years). The interaction between increased supraventricular activity (SVA) top quartile of either PACs/hour or supraventricular tachycardias/hour) and mean heart rate (mHR) as regards AF risk was assessed in multivariable Cox regression analyses adjusted for age, sex, height, BMI, systolic blood pressure, antihypertensive medication, smoking and homeostasis model assessment of insulin resistance., Results: There were 80 (21%) incident cases of AF. Below median mHR (80 bpm/75 bpm for women/men) was associated with increased AF incidence (HR: 1.89, 95% CI 1.18 to 3.02, p=0.008). There was no correlation between mHR and SVA (p=0.6) or evidence of a multiplicative interaction between these factors for AF risk (p for interaction=0.6) In the group with both increased SVA and below median mHR (17% of the population) the relative risk of AF was very high (HR 4.5, 95% CI 2.2 to 9.1, p=0.001)., Conclusion: Low mHR at 24hECG independently predicts AF, but there is no association between mHR and SVA, and these factors are independent as regards AF risk. Subjects with both low mHR and increased SVA have high AF risk., Competing Interests: Competing interests: SJ-M is a previous medical director of Cardiome Inc., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: Firefighting-related environmental and physiological factors associated with cardiovascular strain may promote arrhythmias and myocardial ischemia, which induce sudden cardiac events (SCE) in susceptible individuals. The present study evaluated electrocardiographic (ECG) changes that may reflect increased SCE risk following simulated live-firefighting., Methods: Using a repeated measures design, ECG tracings from 32 firefighters were recorded 12-hours post-firefighting in a residential structure and compared with a 12-hour control period., Results: Ventricular arrhythmias were present in 20%, and ST segment changes indicative of myocardial ischemia in 16%, of firefighters 12-hours post-firefighting that were not detected in the control period., Conclusion: Live-firefighting induces significant ECG changes that include ventricular arrhythmias and ST segment changes, which may reflect myocardial ischemia. The implications of such ECG changes explaining increased cardiovascular risk in firefighters warrants further research.

Objectives: The aim of this study was to examine the relationship between residual premature atrial contractions (PACs) originating from non-pulmonary veins (PVs), which do not initiate atrial fibrillation (AF), and AF recurrence after ablation., Background: Residual atrial ectopic beats that trigger AF from non-PVs (non-PV AF triggers) after catheter ablation are among the major causes of AF recurrence. However, little is known about the impact of non-PV PACs on AF recurrence., Methods: This retrospective study included 565 consecutive patients who underwent first-time AF ablation at our institution. After PV isolation, we infused isoproterenol to provoke non-PV AF triggers and/or non-PV PACs. We excluded 26 patients with non-PV AF triggers and 3 patients who underwent ablation of non-PV PACs, and finally analyzed 536 patients. Non-PV PACs were defined as ectopic beats that were constantly observed with the same intra-atrial activation patterns from non-PVs., Results: Residual non-PV PACs during the procedure were observed in 112 patients (21%). There was no significant difference in the AF recurrence rate between patients with non-PV PACs (35 of 112, 31%) and those without (145 of 424, 34%; log-rank p = 0.69), during a median follow-up of 670 days. Age- and sex-adjusted hazards for AF recurrence were also similar between the 2 groups., Conclusions: The similar AF recurrence rate in patients with and without non-PV PACs suggests that the additional ablation of non-PV PACs has limited effect on AF recurrence., (Copyright © 2019 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: Recent anticoagulation trials in all-comer cryptogenic stroke patients have yielded equivocal results, reinvigorating the focus on identifying reproducible markers of an atrial myopathy. We investigated the role of excessive premature atrial complexes (PACs) in ischaemic stroke, including cryptogenic stroke and its association with vascular risk factors., Methods and Results: A case-control study was conducted utilising a multicentre institutional stroke database to compare 461 patients with an ischaemic stroke or transient ischaemic attack (TIA) with a control group consisting of age matched patients without prior history of ischaemic stroke/TIA. All patients underwent 24-hour Holter monitoring during the study period and atrial fibrillation was excluded. An excessive PAC burden, defined as ≥200 PACs/24 hours, was present in 25.6% and 14.7% (p<0.01), of stroke/TIA and control patients, respectively. On multivariate regression, excessive PACs (OR 1.97; 95% CI 1.29 to 3.02; p<0.01), smoking (OR 1.58; 95% CI 1.06 to 2.36; p<0.05) and hypertension (OR 1.53; 95% CI 1.07 to 2.17; p<0.05) were independently associated with ischaemic stroke/TIA. Excessive PACs remained the strongest independent risk factor for the cryptogenic stroke subtype (OR 1.95; 95% CI 1.16 to 3.28; p<0.05). Vascular risk factors that promote atrial remodelling, increasing age (≥75 years, OR 3.64; 95% CI 2.08 to 6.36; p<0.01) and hypertension (OR 1.54; 95% CI 1.01 to 2.34; p<0.05) were independently associated with excessive PACs., Conclusions: Excessive PACs are independently associated with cryptogenic stroke and may be a reproducible marker of atrial myopathy. Prospective studies assessing their utility in guiding stroke prevention strategies may be warranted., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: The consumption of yerba mate (YM) (Ilex paraguariensis) is common in South America and is now used all over the world. It contains many bioactive substances that can be beneficial. There is also the opinion that it may have harmful effects on heart rhythm, but no studies have been found on this., Objective: The aim of this study was to evaluate the acute effect of YM on heart rhythm in patients referred for a Holter study., Method: A before and after pseudo-experimental clinical study was conducted by performing a Holter on 50 habitual users of YM, and another one after 24 without YM consumption. The use of other products that could interfere was also controlled., Results: The mean age of the subjects was 55±15 years, and 52% were women. At least one vascular risk factor was found in 78%, with 44% structural heart disease, and 90% taking cardiovascular medication. The heart rate (HR) with and without YM was similar. Only the minimum hourly HR was lower when taking YM (61±10 vs. 63±9, P=.021). There was no significant difference in the incidence of sustained or non-sustained arrhythmias, or in ventricular extrasystoles. The total number of supra-ventricular premature beats was higher without YM (952±3,538 vs. 1,294±5,201, P=.014) and also the maximum hourly (86±302 vs. 107±360, P=.032). There was no difference in HR variability., Conclusions: In cardiology patients, usual users of YM, habitual consumption was not associated with significant changes in HR or an increase in the incidence of arrhythmias. There was less ectopic supraventricular activity., (Copyright © 2018 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.)

Atrial fibrillation (AF) is associated with increased morbidity and mortality. We sought to determine whether atrial premature complexes (APCs) detected during a standard exercise stress test (EST) in patients undergoing cardiac rehabilitation (CR) are associated with an increased risk of AF. The present study population comprised 6,523 consecutive patients without prior AF who participated in a CR program in a tertiary medical center in years 2009 to 2016. Multivariate analysis was used to identify the association between APCs during the baseline EST at CR and the risk for the development of AF over a mean follow-up period of 2.5 years. A total of 213 (3.7%) patients had APCs during their EST. Despite being older (mean age 63 ± 13 years old vs 58 ± 13; p <0.001, respectively), no other statistically significant differences were documented. Kaplan-Meier survival analysis showed that the rate of AF development during follow-up was significantly higher in patients with APCs at baseline EST (11%) as compared with those without APCs (5%; log-rank p <0.001 for the overall difference during follow-up). Consistently, multivariate analysis showed that patients with APCs showed >twofold increase risk for AF compared with those without APCs (hazard ratio 2.1; 95% confidence interval 1.36 to 3.25; p <0.001). In conclusion, our findings suggest that APCs detected during EST in patients participating in the CR program independently predict AF and can be used to improve risk stratification in this population., (Copyright © 2018. Published by Elsevier Inc.)

Background: Atrial remodeling, vagal tone, and atrial ectopic triggers are suggested to contribute to increased incidence of atrial fibrillation (AF) in endurance athletes. How these parameters change with increased lifetime training hours is debated., Hypothesis: Atrial remodeling occurs in proportion to total training history, thus contributing to elevated risk of AF., Methods: We recruited 99 recreational endurance athletes, subsequently grouped according to lifetime training hours, to undergo evaluation of atrial size, autonomic modulation, and atrial ectopy. Athletes were grouped by self-reported lifetime training hours: low (<3000 h), medium (3000-6000 h), and high (>6000 h). Left atrial (LA) volume, left ventricular (LV) dimensions, and LV systolic and diastolic function were assessed by echocardiography. We used 48-hour ambulatory electrocardiographic monitoring to determine heart rate, heart rate variability, premature atrial contractions, and premature ventricular contractions., Results: LA volume was significantly greater in the high (+5.1 mL/m 2 , 95% CI: 1.3-8.9) and medium (+4.2 mL/m 2 , 95% CI: 0.2-8.1) groups, compared with the low group. LA dilation was observed in 19.4%, 12.9%, and 0% of the high, medium, and low groups, respectively (P = 0.05). No differences were observed between groups for measures of LV dimensions or function. Minimum heart rate, parasympathetic tone expressed using heart rate variability indices, and premature atrial contraction and premature ventricular contraction frequencies did not differ between groups., Conclusions: In recreational endurance athletes, increased lifetime training is associated with LA dilation in the absence of increased vagal parameters or atrial ectopy, which may promote incidence of AF in this cohort., (© 2018 Wiley Periodicals, Inc.)

Background: In patients with the long QT syndrome (LQTS), a sudden increase in heart rate can cause T-wave alternans (TWA) with beat-to-beat alternating polarity of T wave. We hypothesized that LQTS patients at high risk for torsades de pointes (TdP) may exhibit momentary atrial or sinoatrial premature beat-induced T-wave inversion (APB-TWI)., Objective: The purpose of this study was to assess the association of APB-TWI with TdP history and with microvolt TWA., Methods: Twenty-four-hour continuous 12-lead electrocardiograms (ECGs) were recorded in 18 healthy subjects and 39 consecutive patients with LQTS types 1 (n = 21), 2 (n = 4), 3 (n = 4), and unidentified (n = 10). Peak TWA was determined by the modified moving average method., Results: The 39 LQTS patients were divided into 2 groups: 10 LQTS patients with TdP history (TdP group) and 29 without (non-TdP group). None of the healthy subjects showed APB-TWI, whereas 38.5% of the LQTS patients (15/39) exhibited APB-TWI. The incidences of APB-TWI and TWA ≥42 μV were significantly higher in the TdP group than in the non-TdP group (APB-TWI: 80% vs 24.1%, P = .006; TWA ≥42 μV: 100% vs 65.5%, P = .04). APB-TWI was inferior in sensitivity for an association with TdP history to TWA ≥42 μV (80% vs 100%) but superior in specificity (75.9% vs 51.7%). Patients with APB-TWI exhibited significantly higher TWA values than those without [median (interquartile range) 73 (55-106.5) vs 48 (37.5-71.8) μV, P = .02]., Conclusion: APB-TWI is an easily measurable ECG pattern and is strongly associated with TdP history as well as TWA ≥42 μV in LQTS patients. APB-TWI and TWA may share pathophysiological mechanisms., (Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Psoriasis is a chronic inflammatory disease associated with cardiovascular disease, for example, myocardial infarction, stroke, cardiovascular death, and arrhythmias. The resting electrocardiogram may carry prognostic information, but limited evidence is available of electrocardiographic findings in subjects with psoriasis. The electrocardiographic results were compared between 1,131 subjects with self-reported psoriasis and 18,397 controls participating in the Danish General Suburban Population Study (GESUS). The mean heart rate was marginally increased in patients with psoriasis (66 ± 11 vs 65 ± 11 beats/min, p = 0.007), but not after adjustment for smoking and body mass index. All other examined electrocardiographic variables, including QT interval corrected for heart rate with the Fridericia formula, PR interval, QRS duration, R axis, P-wave duration in lead V1, P-terminal force, J point elevation in lead V1, electrocardiographic criteria for left ventricular hypertrophy, electrocardiographic signs of previous myocardial infarction, and premature ventricular or supraventricular complexes, respectively, were comparable between the 2 groups. In conclusion, psoriasis was associated with a marginal increase in resting heart rate, which was driven by smoking and increased body mass index. All other examined electrocardiographic variables were similar between the 2 groups. The results suggest that psoriasis per se is not associated with significant abnormalities of the electrocardiogram., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: The clinical significance of atrial premature complexes (APCs) during exercise is unclear., Hypothesis: Frequent APCs during exercise provides prognostic information., Methods: A total of 998 patients were divided into 2 groups based on the presence of frequent APCs during treadmill testing (>5 beats per stage): the FAPC group (n = 128) vs the non-FAPC group (n = 870). The primary outcome was new-onset atrial fibrillation or flutter (AF/AFL) during follow-up period (356.2 ± 131.1 days)., Results: Mean age was 56.0 ± 10.2 years in the FAPC group and 52.6 ± 12.0 years in the non-FAPC group (P = 0.001). Baseline electrocardiographic and echocardiographic findings were not significantly different between the 2 groups. During exercise, maximal heart rate did not differ between the 2 groups. Chronotropic incompetence was more prevalent in the FAPC group than in the non-FAPC group (P = 0.04). During follow-up, the FAPC group had a higher incidence of AF/AFL than did the non-FAPC group (7 patients [5.5%] vs 5 patients [0.6%]; P < 0.001). Treadmill-induced frequent APCs (adjusted hazard ratio [HR]: 15.23, 95% confidence interval: 4.59-50.56, P < 0.001), chronotropic incompetence (adjusted HR: 19.95, 95% CI: 6.02-66.10, P < 0.001), and palpitation as a reason for treadmill testing (adjusted HR: 5.72, 95% CI: 1.64-20.00, P = 0.01) were independent risk factors that predicted new-onset AF/AFL., Conclusions: Frequent APCs during treadmill testing was associated with development of AF/AFL in this study. Close monitoring for further AF/AFL development is needed in these patients., (© 2018 Wiley Periodicals, Inc.)

Aims: Atrial fibrillation (AF) is increasingly observed in patients with congenital heart defects (CHDs) who survive nowadays into adulthood. Yet, predictors of AF are scarce in this high-risk population. This study therefore examined the predictive ability of atrial extrasystole (AES) for development of AF in CHD patients., Methods and Results: Adult CHD patients who had a 24 h Holter registration were followed to determine who developed AF. A total of 573 patients (49% male, mean age 35 ± 12 years) were included; they had a simple/complete repaired CHD (n = 279), complex repaired CHD (n = 251), or univentricular heart (UVH, n = 43). Ageing (P < 0.0001), female gender (P = 0.028), UVH (P = 0.0010), and left atrial dilatation (P = 0.0025) were associated with the number of AES. During a median follow-up of 51.6 months (interquartile range 22.8-85.7), 29 patients (5%) developed de novo AF. An one-point increase in the number of logtotal-AES was associated with a two-fold higher risk of AF development (hazard ratio 1.95; 95% confidence interval 1.21-3.13; P = 0.016). C-statistic for left atrial dilatation, complexity, and age had a good discriminative ability for the incidence of AF with a C-statistic of 84.5%. The addition of the total number of AES/24 h to this model increased C-statistic to 88.4%., Conclusion: Atrial extrasystole occur relatively frequent in adult CHD patients compared with patients with other cardiac diseases. This is the first study that showed an association between an increased AES frequency and a higher risk of AF development in CHD patients., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)

Introduction: The significance of premature atrial contraction (PAC) count and supraventricular runs (SVR) for the risk of development of new-onset atrial fibrillation (AF) in patients with coronary artery disease (CAD) is not well established., Methods: The Innovation to Reduce Cardiovascular Complications of Diabetes at the Intersection (ARTEMIS) study cohort consisted of 1,946 patients with CAD who underwent clinical and echocardiographic examinations, 24-hour ambulatory ECG monitoring, and laboratory tests. After excluding patients who were not in sinus rhythm at baseline or were lost from the follow-up, the present study included 1,710 patients. SVR was defined as at least four PACs in a row with a duration <30 seconds., Results: During a follow-up for an average 5.6 ± 1.5 years, new-onset AF was identified in 143 (8.4%) patients. In the univariate analysis, both SVR and PAC count were associated with the development of new-onset AF. When SVR and PAC count were adjusted with the established AF risk markers of the modified CHARGE-AF model in the Cox multivariate regression analysis, both parameters remained significant predictors of the occurrence of new-onset AF (HR = 2.529, 95 % CI = 1.763-3.628, P ˂ 0.001 and HR = 8.139 for ≥1,409 PACs [the fourth quartile] vs. ≤507 PACs [the first quartile], 95 % CI = 3.967-16.696, P ˂ 0.001, respectively). Together these parameters improved the C-index of the established AF risk model from 0.649 to 0.718, P < 0.001., Conclusion: Including SVR and PAC count to the established AF risk model improves the discrimination accuracy in predicting AF in patients with CAD., (© 2017 Wiley Periodicals, Inc.)

Frequent premature atrial complexes (PACs) are universal in the general population; however, their clinical significance is unclear. We hypothesize that frequent PACs are associated with increased risk of stroke and death. The PubMed (from 1966 to April 2017) and Embase (from 1974 to April 2017) databases were searched for longitudinal studies that reported the relation of PACs with incidence of stroke and death with various etiologies. Study quality was evaluated, and the relative risks (RR) of unfavorable outcomes in subjects with frequent PACs vs those without were calculated. Eleven studies with overall high quality were eligible according to inclusion criteria. The meta-analysis demonstrated that frequent PACs were associated with an increased risk of stroke (unadjusted RR: 2.20, 95% confidence interval [CI]: 1.79-2.70; adjusted RR: 1.41, 95% CI: 1.25-1.60) and death from all causes (unadjusted RR: 2.17, 95% CI: 1.80-2.63; adjusted RR: 1.26, 95% CI: 1.13-1.41), cardiovascular diseases (unadjusted RR: 2.89, 95% CI: 2.20-3.79; adjusted RR: 1.38, 95% CI: 1.24-1.54), and coronary artery disease (unadjusted RR: 2.74, 95% CI: 1.64-4.58; adjusted RR: 1.74, 95% CI: 1.27-2.37). No significant publication bias was detected. The association was robust in sensitivity analysis, subgroup analysis, and pooled analysis of estimates adjusting for confounding factors. Frequent PACs are not benign phenomena; they are associated with higher risk of unfavorable outcomes. Further research on the optimal management of subjects with frequent PACs is urgently required., (© 2017 Wiley Periodicals, Inc.)

Background: Supraventricular ectopic complexes (SVEC) originating in the pulmonary veins are known triggers of atrial fibrillation (AF) which led to the development of pulmonary vein isolation for AF. However, the long-term prevalence of SVEC after catheter ablation (CA) as compared to antiarrhythmic medication (AAD) is unknown. Our aims were to compare the prevalence of SVEC after AAD and CA and to estimate the association between baseline SVEC burden and AF burden during 24months of follow-up., Methods: Patients with paroxysmal AF (N=260) enrolled in the MANTRA PAF trial were treated with AAD (N=132) or CA (N=128). At baseline and 3, 6, 12, 18 and 24months follow-up patients underwent 7-day Holter monitoring to assess SVEC and AF burden. We compared SVEC burden between treatments with Wilcoxon sum rank test., Results: Patients treated with AAD had significantly lower daily SVEC burden during follow-up as compared to CA (AAD: 19 [6-58] versus CA: 39 [14-125], p=0.003). SVEC burden increased post-procedurally followed by a decrease after CA whereas after AAD SVEC burden decreased and stabilized after 3months of follow-up. Patients with low SVEC burden had low AF burden after both treatments albeit this was more pronounced after CA at 24months of follow-up., Conclusion: AAD was superior to CA in suppressing SVEC burden after treatment of paroxysmal AF. After CA SVEC burden increased immediately post-procedural followed by a decrease whereas after AAD an early decrease was observed. Lower SVEC burden was highly associated with lower AF burden during follow-up especially after CA., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: To determine the yield of 48-hour Holter monitoring in children with unexplained palpitations and the significance of associated symptoms., Methods: This descriptive study was conducted at the Children's Hospital and Institute of Child Health, Lahore, Pakistan, from January 1 to December 31, 2015. All children above 5 years of age with history of intermittent palpitations and normal basic cardiovascular workup were enrolled. A 48-hour Holter study was performed using Motara Holter Monitoring System. Frequency of various symptoms and abnormal Holter findings were analysed. SPSS 21 was used for data analysis., Results: Of the 107 patients, 69(64.5%) were males and 38(34.5%) females. The median age was 10 years (interquartile range: 5-18 years). Most common concomitant symptoms with palpitation included syncope/pre-syncope in 35(32.7%) patients, chest pain 22(20.5%), shortness of breath 21(19.6%) and colour change/pallor 11(10.3%). Holter recording was positive in 40(37%) patients. Frequent premature ventricular contractions 12(11.2%) and atrial ectopic beats 9(8.4%) were the most common findings. Holter findings were significantly more common in patients with history of shortness of breath and colour change/pallor during palpitations (p=0.002)., Conclusions: Extended 24-hour Holter monitoring in children with palpitations was an inexpensive, non-invasive investigation with a reasonably high diagnostic yield in detecting arrhythmias.

Several reports have suggested that particulate matter (PM) exposure increases the risk for atrial arrhythmias. However, data from large-scale epidemiologic studies supporting this hypothesis are lacking. We examined the association of PM <2.5 μm in diameter (PM 2.5 ) concentration with premature atrial contractions (PACs) in 26,609 (mean age=65±9.4 years; 55% female; 41% black) participants from the REGARDS (REasons for Geographic And Racial Differences in Stroke) study. Estimates of short- (2 weeks) and long-term (1 year) PM 2.5 exposure were computed before each participant's baseline visit using geographic information system data on the individual level at the coordinates of study participants' residences. PACs were identified from baseline electrocardiograms. A total of 2140 (8.2%) participants had evidence of PACs on the baseline electrocardiogram. Short-term PM 2.5 (per 10 μg/m 3 ) exposure was not associated with PACs (OR=1.09, 95% CI=0.98, 1.23). Increases in long-term PM 2.5 (per 10 μg/m 3 ) were associated with PACs (OR=1.40, 95% CI=1.10, 1.78). Interactions were not detected for short- and long-term PM 2.5 exposure by age, sex, or race. Long- but not short-term PM 2.5 exposure is associated with PACs. This suggests a role for long-term PM 2.5 exposure in initiating supraventricular arrhythmias that are triggered by PACs.

Aims: The risk of incident atrial fibrillation (AF) can be estimated by clinical parameters in the Framingham AF risk model. Elevated N-terminal pro-B-type natriuretic peptide (NT-proBNP) and increased rate of premature atrial contractions (PACs) have been shown to be associated with AF, but the additive value of both of these biomarkers in the Framingham AF risk model has not been fully examined., Methods and Results: A total of 646 subjects from the Copenhagen Holter Study (mean age 64.4 ± 6.8 years, 41.6% women) with no history of prior AF, stroke or cardiovascular disease were followed for the diagnosis of incident AF or death (median follow-up time 14.4 years). Median NT-proBNP was 6.7 pmol/L (IQR: 3.6-13.5), median PAC count was 1.4 beats/h (IQR: 0.6-4.5), 71 (11.0%) subjects developed AF, and 244 (37.8%) died. Multiple Cox regression including Framingham AF risk score, log-transformed NT-proBNP, and log-transformed PAC showed a significant increase in AF hazard risk [hazard ratio (HR) 1.45, 95% confidence interval (CI) 1.14-1.85, P = 0.002; HR 1.23, 95% CI 1.09-1.39, P = 0.001]. The addition of PAC to the Framingham AF risk model significantly improved the time-dependent area under the receiver operating characteristic curve (AUC 65.6 vs. 72.6; P = 0.008), while the addition of NT-proBNP did not., Conclusion: Atrial fibrillation risk discrimination was significantly improved by the addition of PAC to the Framingham AF risk model, but not by the addition of NT-proBNP., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)

Background and Purpose: Stroke is independently associated with the common conditions of hypokalemia and supraventricular ectopy, and we hypothesize that the combination of excessive supraventricular ectopic activity and hypokalemia has a synergistic impact on the prognosis in terms of stroke in the general population., Methods: Subjects (55-75 years old) from the Copenhagen Holter Study cohort (N=671) with no history of atrial fibrillation or stroke were studied-including baseline values of potassium and ambulatory 48-hour Holter monitoring. Excessive supraventricular ectopic activity is defined as ≥30 premature atrial complexes per hour or any episodes of runs of ≥20. Hypokalemia was defined as plasma-potassium ≤3.6 mmol/L. The primary end point was ischemic stroke. Cox models were used., Results: Hypokalemia was mild (mean, 3.4 mmol/L; range, 2.7-3.6). Hypokalemic subjects were older (67.0±6.94 versus 64.0±6.66 years; P <0.0001) and more hypertensive (165.1±26.1 versus 154.6±23.5 mm Hg; P <0.0001). Median follow-up time was 14.4 years (Q1-Q3, 9.4-14.7 years). The incidence of stroke was significantly higher in the hypokalemic group (hazard ratio, 1.84; 95% confidence interval, 1.04-3.28) after covariate adjustments, as well as in a competing risk analysis with death (hazard ratio, 1.51; 95% confidence interval, 1.12-2.04). Excessive supraventricular ectopic activity was also associated with stroke (hazard ratio, 2.23; 95% confidence interval, 1.33-3.76). The combination of hypokalemia and excessive supraventricular ectopic activity increased the risk of events synergistically. Stroke rate was 93 per 1000 patient-year ( P <0.0001) in this group (n=17) compared with 6.9 (n=480); 11 (n=81), and 13 (n=93) per 1000 patient-year in the groups without the combination., Conclusions: The combination of hypokalemia and excessive supraventricular ectopy carries a poor prognosis in terms of stroke., (© 2017 American Heart Association, Inc.)

Knowledge of the mechanism underlying post-operative atrial fibrillation (PoAF) is essential for development of preventive measures. The incidence and characteristics of both PoAF and supraventricular premature beats triggering PoAF, their interrelationship and alterations over time have never been examined. The goal of this study is therefore to examine the correlation between the incidence and characteristics of supraventricular premature beats (SVPBs) and PoAF episodes in patients undergoing CABG in the first five post-operative days., Methods: PoAF episodes (N=327) and SVPBs (N=141,873) were characterized in 29 patients (63±9 years; 22 (76%) male) undergoing coronary artery bypass grafting and compared with a control group of patients without PoAF by using continuous cardiac rhythm monitoring during the first 5 days after surgery., Results: Most patients (N=18, 62%) had multiple PoAF episodes; the median number of PoAF episodes per patient was 3 and varied between 1 and 139. The majority of PoAF episodes developed on the second and third post-operative day (55%). The averaged median duration of PoAF episodes per patient was 469±1085 min. Patients with PoAF had a higher SVPBs burden compared to subjects without PoAF (0.9% vs 0.2%, P<.001). SVPBs initiating PoAF had shorter coupling intervals than SVPBs which did not initiate PoAF episodes (58% vs 64% (P<.001) and were preceded by heart rate acceleration., Conclusion: PoAF episodes are mainly repetitive though transient in nature. There was a considerable inter-individual variation in both AF and SVPB characteristics, despite a similar underlying clinical profile. The SVPB burden is higher in patients with PoAF and the mode of onset is characterized by short coupled SVPBs. Determination of individual post-operative dysrhythmia profiles enables identification of patients at risk for developing PoAF., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Patients with chronic obstructive pulmonary disease (COPD) have an increased risk for both supraventricular and ventricular arrhythmias. Autonomic dysregulation may be responsible for the development of arrhythmias in these patients, and its analysis could be useful for identifying those at high risk for arrhythmias., Study Question: Our purpose is to analyze the role of acceleration capacity (AC) and deceleration capacity (DC), novel markers of the autonomic balance, as potential arrhythmic risk predictors in patients with COPD., Study Design: We prospectively included 47 patients diagnosed with COPD, and a control group of 64 age-matched subjects without COPD. AC and DC values were obtained using 24-hour Holter monitoring. The arrhythmias were isolated premature atrial complexes, supraventricular tachycardias, isolated premature ventricular beats (PVC), and combined ventricular arrhythmias consisting in ventricular tachycardias or more than 10 PVC per hour., Results: Supraventricular arrhythmias and isolated PVC were more frequent in the COPD group. The DC was significantly lower (3.10 vs. 5.60, P < 0.0001) and AC higher (-4.60 vs. -6.60, P = 0.002) in patients with COPD. DC was identified as a predictor of arrhythmic events with an area under the curve (AUC) for premature atrial complexes >70/d of 0.72 (0.56-0.87, P = 0.013), for supraventricular tachycardias 0.76 (0.62-0.90, P = 0.002), and for combined ventricular arrhythmias 0.69 (0.54-0.82, P = 0.025). AC was predictor only for combined ventricular arrhythmias with an AUC of 0.74 (0.58-0.85, P = 0.002)., Conclusions: Patients with COPD associate a significant autonomic imbalance and a higher incidence of arrhythmias. DC could be a strong predictor for supraventricular and ventricular arrhythmias in patients with COPD with no clinically apparent cardiac disease. AC could be useful alongside with DC regarding the risk for ventricular arrhythmias, but seems to have lesser value as a predictor for supraventricular arrhythmias.

Background and Purpose: Runs of premature atrial complexes (PACs) are common in stroke patients and perceived to be clinically insignificant, but their prognostic significance is unclear. This study investigated the association between runs of PACs in ischemic stroke patients and the risk of recurrent ischemic strokes/transient ischemic attacks (TIAs) or death., Methods: The study included consecutive patients admitted with an ischemic stroke from August 2008 to April 2011. Patients with known and newly detected atrial fibrillation were excluded. Runs of PACs were defined as 3 or more PACs lasting less than 30 seconds during 48 hours of continuous inpatient cardiac telemetry. The patients were followed for 4 years or until death, whichever came first. They were stratified according to stroke severity. The combined primary endpoint was a recurrent ischemic stroke/TIA or death., Results: Of the 565 patients included in the study, 28% had runs of PACs. Patients with runs of PACs were likely to be older, female, and to have experienced more severe strokes. During the follow-up, 210 (37%) patients had a recurrent ischemic stroke/TIA (n = 73) or died (n = 137) respectively. Among the 489 patients who had mild-to-moderate strokes, runs of PACs were associated with recurrent ischemic strokes/TIAs or death (hazard ratio = 1.47; 95% CI 1.06-2.04; P = .023)., Conclusion: Runs of PACs were frequent in patients with acute ischemic strokes and sinus rhythm, and they were independently associated with an increased risk of recurrent ischemic strokes/TIAs or death in patients with mild-to-moderate strokes., (Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Background: It is currently unknown if premature atrial contractions (PACs) detected on the routine screening electrocardiogram are associated with an increased risk of ischemic stroke., Methods: We examined the association between PACs and ischemic stroke in 22,975 (mean age 64 ± 9.2; 56% women; 40% black) participants from the Reasons for Geographic and Racial Differences in Stroke study. Participants who were free of stroke at baseline were included. PACs were detected from centrally read electrocardiograms at baseline. Cox regression was used to examine the association between PACs and ischemic stroke events through March 31, 2014., Results: PACs were present in 1,687 (7.3%) participants at baseline. In a Cox regression model adjusted for stroke risk factors and potential confounders, PACs were associated with an increased risk of ischemic stroke (hazards ratio (HR) 1.34, 95% CI 1.04-1.74). The relationship was limited to non-lacunar infarcts (HR 1.42, 95% CI 1.08-1.87), and not lacunar strokes (HR 1.01, 95% CI 0.51-2.03). An interaction by sex was detected, with the association between PACs and ischemic stroke being stronger among women (HR 1.82, 95% CI 1.29-2.56) than men (HR 1.03, 95% CI 0.69-1.52; p-interaction = 0.0095)., Conclusion: PACs detected on the routine electrocardiogram are associated with an increased risk for non-lacunar ischemic strokes, especially in women., Competing Interests: The authors declare no conflicts of interest., (© 2016 S. Karger AG, Basel.)

Background: Supraventricular and ventricular premature complexes (SVPC and VPC, respectively) are associated with chronic obstructive pulmonary disease (COPD) and with increased mortality in COPD patients. However, there are few reports on the causes of arrhythmia in COPD patients., Objectives: This study explores the associations between cardiopulmonary dysfunction and COPD by comparing patients with defined arrhythmias (>100 beats per 24 h) and those without, based on 24-hour electrocardiogram (ECG) recordings., Methods: Patients with arrhythmia underwent a 24-hour ECG and subsequent pulmonary function tests, computed tomography, ECG, 6-min walk test (6MWT), and BODE (body mass index, airflow obstruction, modified Medical Research Council Dyspnoea Scale, exercise capacity) index calculation., Results: Of 103 study patients (71 COPD patients and 32 at-risk patients), 36 had VPC, 45 had SVPC, 20 had both, and 42 had neither. The predicted post-bronchodilator forced expiratory volume in 1 s, the proportion of low-attenuation area on computed tomography, and BODE index values were significantly worse in the SVPC and VPC groups compared with the corresponding reference groups. Patients in the VPC group showed significantly increased right ventricular pressure and increased desaturation in the 6MWT compared with the reference group. In the multivariate analyses, bronchodilator use was a significant risk factor in the SVPC group, whereas in the VPC group, all parameters of the BODE index except for the dyspnoea score were identified as risk factors., Conclusions: Increased SVPC might be caused by bronchodilator use, whereas increased VPC is likely related to the peculiar pathophysiology of COPD., (© 2015 S. Karger AG, Basel.)

Identification of precursors of atrial fibrillation (AF) may lead to early detection and prevent associated morbidity and mortality. This study aimed to examine the association between frequent atrial premature complexes (APCs) and incidence of AF. For this retrospective cohort study, we analyzed Holter recordings obtained from 2000 to 2010 of 1,357 veterans free of AF at baseline. All pertinent data in electronic medical records were reviewed to ascertain baseline characteristics. Holter groups with frequent (≥100/day) and infrequent (<100/day) APCs were compared for development of new AF over a median follow-up of 7.5 years. Multivariate Cox regression analyses were performed before and after propensity score matching. Mean age was 64 years with 93% men. Mean body mass index, hemoglobin A1C, low-density lipoprotein, left atrial size, and heart rate were 31.24 kg/m(2), 6.42%, 107.92 mg/dl, 4.26 cm, and 73 beats/min, respectively. AF was noted in 21.8% of patients with frequent APCs compared to 5.6% of those with infrequent APCs. After adjusting for demographics, medication use, co-morbidities, and laboratory and echocardiographic findings, multivariate Cox regression analyses confirmed frequent APCs to be independently associated with higher incidence of AF (hazard ratio [HR] 2.97, 95% confidence interval [CI] 1.85 to 4.80; p <0.001). In propensity-matched groups, this association remained significant (HR 2.87, 95% CI 1.65 to 4.98; p <0.001). Additionally, atrial couplets (≥50/day), atrial bigeminy (≥50/day), frequent runs of ≥3 APCs (≥20 runs/day), and longer runs (≥10 beats/run) were significantly associated with AF (HR 3.11, 3.67, 2.94, and 1.73, respectively, all p <0.05). In conclusion, frequent APCs (≥100/day) are associated with greater risk of AF., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objective: Fetal tachyarrhythmias complicate 0.5% of pregnancies, with high morbidity and mortality. We hypothesized that maternal factors may predispose to fetal supraventricular tachycardia (SVT)., Study Design: We reviewed medical records of all 124 mothers who presented to the Vanderbilt Fetal Cardiology Clinic from 2004 to 2010 for fetal arrhythmias, excluding heart block. Maternal factors were compared between 28 fetuses with SVT and a control group of 112 fetuses screened for noncardiac conditions. The proportions were analyzed using chi-square or Fisher exact test for categorical variables and Wilcoxon rank sum test for continuous variables., Results: Of maternal factors, thyroid disease was statistically significant compared with controls. Among mothers whose fetuses had SVT, 21% had thyroid disease (83% hypothyroidism) compared with 3% of controls (p < 0.001)., Conclusion: In this cohort, the maternal thyroid disease was more common in fetuses with SVT compared with controls (odds ratio = 9.8, 95% confidence interval 2.3-42.3), suggesting closer screening for fetal arrhythmias and SVT in mothers with thyroid disease. Also, routine screening of thyroid functions and thyroid autoantibodies may be warranted in mothers of fetuses with SVT., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)