Alcohol Intake is Significantly Associated with Atrial Flutter in Patients under 60 Years of Age and a Shorter Right Atrial Effective Refractory Period

The impact of lifestyle factors on atrial fibrillation

Atrial fibrillation (AF), with its significant associated morbidity and mortality contributes to significant healthcare utilisation and expenditure. Given its progressively rising incidence, strategies to limit AF development and progression are urgently needed. Lifestyle modification is a potentially potent but underutilised weapon against the AF epidemic. The purpose of this article is to review the role of lifestyle factors as risk factors for AF, outline potential mechanisms of pathogenesis and examine the available evidence for lifestyle intervention in primary and secondary AF prevention. It will also highlight the need for investment by physicians, researchers, health services and governments in order to facilitate delivery of the comprehensive, multidisciplinary AF care that is required to manage this complex and multifactorial disease.

2023 Cardiac Society of Australia and New Zealand Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation

Catheter ablation for atrial fibrillation (AF) has increased exponentially in many developed countries, including Australia and New Zealand. This Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation from the Cardiac Society of Australia and New Zealand (CSANZ) recognises healthcare factors, expertise and expenditure relevant to the Australian and New Zealand healthcare environments including considerations of potential implications for First Nations Peoples. The statement is cognisant of international advice but tailored to local conditions and populations, and is intended to be used by electrophysiologists, cardiologists and general physicians across all disciplines caring for patients with AF. They are also intended to provide guidance to healthcare facilities seeking to establish or maintain catheter ablation for AF.

Association Between Family History and Early-Onset Atrial Flutter Across Racial and Ethnic Groups

BACKGROUND

Genetic and familial contributions to early-onset atrial fibrillation are described primarily in individuals of European ancestry. However, the role of racial and familial contributions in the pathogenesis of early-onset atrial flutter (EOAFL) is unclear.

METHODS AND RESULTS

In this cross-sectional study, participants were enrolled prospectively from 2015 to 2021 in multiple academic centers with a diagnosis of atrial flutter (AFL) confirmed by ECG. EOAFL was defined as a diagnosis of AFL before age 66 years with no concomitant or previous diagnosis of atrial tachyarrhythmias. Family history was adjudicated through baseline questionnaires and direct family interviews about the diagnosis of atrial tachyarrhythmias, stroke, and cardiomyopathy. The primary exposure was a positive family history in first-degree relatives, and the primary outcome was the odds of EOAFL versus late-onset AFL. A total of 909 patients were enrolled. Participants with a positive family history of atrial tachyarrhythmias were younger, less likely to be of Black race, and more likely to have EOAFL. The adjusted odds ratio (OR) for EOAFL in those with a positive family history was 1.8 (95% CI, 1.1-3.0). There was an increased odds of EOAFL in those of Black race (OR, 2.1 [95% CI, 1.4-3.2]), alcohol use (OR, 1.6 [95% CI, 1.0-2.6]), and obstructive sleep apnea (OR, 1.9 [95% CI, 1.0-3.4]). Use of cardioselective β blockers or calcium channel blockers before the diagnosis of AFL were associated with a lower odds of EOAFL (OR, 0.5 [95% CI, 0.2-0.9]).

CONCLUSIONS

These findings suggest a potentially hereditary predisposition to EOAFL across race and ethnicity, warranting further study of the genetic contributions to AFL.

Alcohol and the risk of all-cause death, atrial fibrillation, ventricular arrhythmia, and sudden cardiac arrest

The risk of having atrial fibrillation (AF) is associated with alcohol intake. However, it is not clear whether sudden cardiac arrest (SCA) and ventricular arrhythmia (VA) including ventricular tachycardia, flutter, or fibrillation have similar associations with alcohol. We aimed to evaluate the association of alcohol intake with all-cause death, new-onset AF, VA, and SCA using single cohort with a sufficient sample size. A total of 3,990,373 people without a prior history of AF, VAs, or SCA was enrolled in this study based on nationwide health check-up in 2009. We classified the participants into four groups according to weekly alcohol consumption, and evaluated the association of alcohol consumption with each outcome. We observed a significant association between mild (hazard ratio [HR] = 0.826; 95% confidence interval [CI] = 0.815-0.838) to moderate (HR = 0.930; 95% CI = 0.912-0.947) drinking with decreased risk of all-cause mortality. However heavy drinking (HR = 1.108; 95% CI = 1.087-1.129) was associated with increased all-cause death. The risk of new-onset AF was significantly associated with moderate (HR = 1.129; 95% CI = 1.097-1.161) and heavy (HR = 1.298; 95% CI = 1.261-1.337) drinking. However, the risk of SCA showed negative association with all degrees of alcohol intake: 20% (HR = 0.803; 95% CI = 0.769-0.839), 15% (HR = 0.853; 95% CI = 0.806-0.902), and 8% (HR = 0.918; 95% CI = 0.866-0.974) lower risk for mild, moderate, and heavy drinkers, respectively. Mild drinking was associated with reduced risk of VA with moderate and heavy drinking having no associations. In conclusion, the association between alcohol and various outcomes in this study were heterogeneous. Alcohol might have different influences on various cardiac disorders.

Changes in alcohol consumption habits and risk of atrial fibrillation: a nationwide population-based study

AIMS

Heavy alcohol consumption is an established risk factor for atrial fibrillation (AF). However, the association between habitual changes in heavy habitual drinkers and incident AF remains unclear. The aim of this study was to evaluate whether absolute abstinence or reduced drinking decreases incident AF in heavy habitual drinkers.

METHODS AND RESULTS

Atrial fibrillation-free participants with heavy alcohol consumption registered in the Korean National Health Insurance Service database between 2005 and 2008 were enrolled. Habitual changes in alcohol consumption between 2009 and 2012 were classified as sustained heavy drinking, reduced drinking, and absolute abstinence. The primary outcome measure was new-onset AF during the follow-up. To minimize the effect of confounding variables on outcome events, inverse probability of treatment weighting (IPTW) analysis was performed. Overall, 19 425 participants were evaluated. The absolute abstinence group showed a 63% lower incidence of AF (IPTW hazard ratio: 0.379, 95% confidence interval: 0.169-0.853) than did the sustained heavy drinking group. Subgroup analysis identified that abstinence significantly reduced incident AF in participants with normal body mass index and without hypertension, diabetes, dyslipidaemia, heart failure, stroke, chronic kidney disease, or coronary artery disease (all P-value <0.05). There was no statistical difference in incident AF in participants with reduced drinking compared with sustained heavy alcohol group.

CONCLUSION

Absolute abstinence could reduce the incidence of AF in heavy alcohol drinkers. Comprehensive clinical measures and public health policies are warranted to motivate alcohol abstinence in heavy drinkers.

Alcohol and Atrial Fibrillation: A Pathophysiologic Perspective

Atrial fibrillation (AF) is the most common cardiac arrhythmia responsible for significant morbidity and mortality. Its burden on patients and the health care system is only expected to increase. Several studies have established a dose-response relationship between the amount and frequency of alcohol consumption and the incidence of new onset AF independent of sex, age, and other risk factors. This causal relationship is mediated by the impact alcohol consumption has on conduction properties of the atrium, structural and cellular effect on cardiac myocytes, and dysregulation of the autonomic nervous system. This article reviews the current literature supporting the link between alcohol consumption and AF while attempting to provide an insight into pathophysiological mechanisms.

Alcohol and Arrhythmias

The association between alcohol consumption and abnormalities of heart rate and rhythm has long been recognized. Significant attention has focused on the risk of atrial fibrillation (AF) and sudden cardiac death (SCD) with excessive alcohol intake. Recent studies have advanced our understanding of these relationships and provided additional insights into potentially arrhythmogenic mechanisms. However, considerable uncertainty remains, such as the level of consumption at which harm begins and whether alcohol plays a role in other arrhythmias. This review characterizes the spectrum of conduction abnormalities and heart rhythm disorders in relation to alcohol consumption. In addition, it discusses the latest epidemiologic and experimental evidence, the potential importance of beverage type and constituent ingredients, and conflicting information on drink definitions, thresholds, and recommendations.

Habitual Alcohol Intake and Risk of Atrial Fibrillation in Young Adults in Korea

IMPORTANCE

Guidelines recommend that all risk factors for early-onset atrial fibrillation, including lifestyle factors, be proactively managed, considering the poor prognosis of the disease. Not much is known about the association of cumulative alcohol intake with the risk of atrial fibrillation in young adults aged 20 to 39 years, especially among heavy drinkers.

OBJECTIVE

To explore the association of alcohol consumption with the risk of incident atrial fibrillation in young adults.

DESIGN, SETTING, AND PARTICIPANTS

Using the National Health Insurance Service database, a nationwide population-based cohort study of adults aged 20 to 39 years without prior atrial fibrillation who underwent 4 serial annual health examinations between 2009 and 2012 was conducted. The cumulative alcohol consumption burden over 4 years was calculated by assigning 1 point to more than moderate drinking (≥105 g of alcohol per week) each year. Additionally, a semiquantitative cumulative burden was calculated by assigning 0, 1, 2, and 3 points to non, mild (<105 g per week), moderate (105-210 g per week), and heavy (≥210 g per week) drinking, respectively. Data were analyzed from May to June 2021.

EXPOSURE

Amount of alcohol intake in 4 years.

MAIN OUTCOMES AND MEASURES

The primary outcome was incident atrial fibrillation during the follow-up period.

RESULTS

A total of 1 537 836 participants (mean [SD] age 29.5 [4.1] years, 1 100 099 [71.5%] male) were included in the final analysis. According to the 4-year cumulative burden of alcohol consumption stratified by moderate to heavy drinking, 889 382 participants (57.8%) were in the burden 0 group, 203 374 participants (13.2%) in the burden 1 group, 148 087 participants (9.6%) in the burden 2 group, 144 023 participants (9.4%) in the burden 3 group, and 152 970 participants (9.9%) in the burden 4 group. During a median (IQR) follow-up of 6.13 (4.59-6.48) years, atrial fibrillation was newly diagnosed in 3066 participants (0.36 per 1000 person-years). Participants with a cumulative burden of 4 points who continued more than moderate drinking for 4 years showed a 25% higher risk of atrial fibrillation compared with 0-point participants who kept non-to-mild drinking over 4 years (adjusted HR, 1.25; 95% CI, 1.12-1.40). In a semiquantitative analysis, participants who sustained heavy drinking for 4 consecutive years were associated with a 47% higher atrial fibrillation risk than those who remained nondrinkers over 4 years (aHR, 1.47, CI 1.18-1.83).

CONCLUSIONS AND RELEVANCE

Persistent moderate to heavy drinking and higher cumulative alcohol consumption burden might increase the risk of atrial fibrillation even in young adults aged 20 to 39 years.

Alcohol Consumption Is Associated With Postablation Recurrence but Not Changes in Atrial Substrate in Patients With Atrial Fibrillation: Insight from a High-Density Mapping Study

Background

The association between alcohol consumption, atrial substrate, and outcomes after atrial fibrillation (AF) ablation remains controversial. This study evaluated the impacts of drinking on left atrial substrate and AF recurrence after ablation.

Methods and Results

We prospectively enrolled 110 patients with AF without structural heart disease (64±12 years) from 2 institutions. High‐density left atrial electroanatomic mapping was performed using a high‐density grid multipolar catheter. We investigated the impact of alcohol consumption on left atrial voltage, left atrial conduction velocity, and AF ablation outcome. Patients were classified as abstainers (<1 drink/wk), mild drinkers (1–7 drinks/wk), or moderate‐heavy drinkers (>7 drinks/wk). High‐density mapping (mean 2287±600 points/patient) was performed on 49 abstainers, 27 mild drinkers, and 34 moderate‐heavy drinkers. Low‐voltage zone and slow‐conduction zone were identified in 39 (35%) and 54 (49%) patients, respectively. There was no significant difference in the proportions of low‐voltage zone and slow‐conduction zone among the 3 groups. The success rate after a single ablation was significantly lower in drinkers than in abstainers (79.3% versus 95.9% at 12 months; mean follow‐up, 18±8 months; P=0.013). The success rate after a single or multiple ablations was not significantly different among abstainers and drinkers. In multivariate analysis, alcohol consumption (P=0.02) and the presence of a low‐voltage zone (P=0.032) and slow‐conduction zone (P=0.02) were associated with AF recurrence after a single ablation, while low‐voltage zone (P=0.023) and slow‐conduction zone (P=0.024) were associated with AF recurrence after a single or multiple ablations.

Conclusions

Alcohol consumption was associated with AF recurrence after a single ablation but not changes in atrial substrate.

Differences in Stroke or Systemic Thromboembolism Readmission Risk After Hospitalization for Atrial Fibrillation and Atrial Flutter

Background

Although atrial fibrillation (AF) and atrial flutter (AFL) are different arrhythmias, they are assumed to confer the same risk of stroke and systemic thromboembolism (STE) despite a lack of available evidence. In this study, we investigated the difference in the risk of stroke or STE after AF and AFL hospitalizations.

Methodology

The National Readmission Database (NRD) 2018 was used to identify AF and AFL patients using appropriate International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes and were followed until the end of the calendar year to identify stroke or STE readmissions. Survival estimates were calculated, and a Cox proportional hazards model was used to calculate the adjusted hazards ratio (aHR) and compare the risk of stroke or STE readmissions between AF and AFL groups.

Results

A total of 215,810 AF and 15,292 AFL patients were identified. AFL patients were more likely to be younger (66 vs. 70 years), male (68% vs. 47%), and had higher prevalence of obesity (25% vs. 22%), obstructive sleep apnea (14% vs. 12%), diabetes mellitus (31% vs. 26%), and alcohol use (6.9% vs. 5.5%) (all p < 0.01). After adjusting for potential patient and hospital-level characteristics, there was a statistically significant decrease in one-year stroke or STE readmission risk in AFL patients compared to AF patients (aHR 0.79 (0.66-0.95); p = 0.01).

Conclusions

AFL patients are commonly younger males with a higher burden of medical comorbidity. There is a decrease in the one-year risk of stroke or STE events in AFL patients compared to AF. The predictors of stroke and STE are similar in both AFL and AF groups. Further studies with longer follow-up and anticoagulation data are needed to verify the results.

Risk of incident atrial fibrillation with low-to-moderate alcohol consumption is associated with gender, region, alcohol category: a systematic review and meta-analysis

AIMS 

The association between low-to-moderate alcohol consumption and atrial fibrillation (AF) has yet to be fully elucidated. The main purpose of this meta-analysis was to estimate the risk of incident AF related to low-to-moderate alcohol consumption.

METHODS AND RESULTS 

A meta-analysis was performed on 13 publications discussing the estimated risk for AF with habitual low-to-moderate alcohol intake in 10 266 315 participants. Graphical augmentations to the funnel plots were used to illustrate the potential impact of additional evidence on the current meta-analysis. Thirteen eligible studies were included in this meta-analysis. We found that moderate alcohol consumption was associated with an increased risk of incident AF in males [hazard ratio (HR) 1.09, 95% confidence interval (CI): 1.07-1.11, P < 0.00001], Europeans (HR 1.32, 95% CI: 1.23-1.42, P < 0.00001), and Asians (HR 1.09, 95% CI: 1.07-1.11, P < 0.00001). Moderate beer consumption was associated with an increased risk of developing AF (HR 1.11, 95% CI: 1.02-1.21, P = 0.01). Low alcohol consumption conferred an increased risk of AF in males (HR 1.14, 95% CI: 1.01-1.28, P = 0.04) and Europeans (HR 1.12, 95% CI: 1.07-1.17, P < 0.00001).

CONCLUSIONS 

This analysis represents the increased risk of incident AF in males, Europeans, and Asians at moderate alcohol consumption levels and in males and Europeans at low alcohol consumption levels. Those who drink any preferred alcohol beverage at moderate levels should be cautious for incident AF. More studies are warranted to find those factors that influence alcohol's effect on predisposing AF.

Risk Thresholds for Total and Beverage-Specific Alcohol Consumption and Incident Atrial Fibrillation

OBJECTIVES

This study sought to characterize associations of total and beverage-specific alcohol consumption with incident atrial fibrillation (AF).

BACKGROUND

Although binge drinking and moderate to high consumption of alcohol are both established risk factors for AF, comparatively less is known about the effect of low alcohol consumption and whether associations differ by specific alcoholic beverages.

METHODS

Using data from the UK Biobank, total and beverage-specific alcohol consumption was calculated as UK standard drinks (8 g alcohol) per week. Past drinkers and those with a history of AF were excluded. Incident AF events were assessed through hospitalization and death records, and dose-response associations were characterized using Cox regression models with correction for regression dilution bias.

RESULTS

We studied 403,281 middle-aged individuals (52.4% female). Over a median follow-up time of 11.4 years (interquartile range: 10.7-12.3), a total of 21,312 incident AF events occurred. A J-shaped association of total alcohol consumption was observed, with lowest risk of AF with fewer than 7 drinks/week. Beverage-specific analyses demonstrated harmful associations of beer/cider consumption with any consumption. In contrast, consumption of red wine, white wine, and spirits up to 10, 8, and 3 drinks/week, respectively, was not associated with increased risk.

CONCLUSIONS

In this predominantly White population, low levels of alcohol consumption (<7 UK standard drinks [56 g alcohol]/week) were associated with lowest AF risk. Low consumption of red and white wine and very low consumption of spirits may not be associated with increased AF risk, whereas any consumption of beer/cider may be associated with harm. These findings may have important implications for the primary prevention of AF that should be explored in future studies.

Frequent drinking is a more important risk factor for new-onset atrial fibrillation than binge drinking: a nationwide population-based study

AIMS

Heavy consumption of alcohol is a known risk factor for new-onset atrial fibrillation (AF). We aimed to evaluate the relative importance of frequent drinking vs. binge drinking.

METHODS AND RESULTS

A total of 9 776 956 patients without AF who participated in a national health check-up programme were included in the analysis. The influence of drinking frequency (day per week), alcohol consumption per drinking session (grams per session), and alcohol consumption per week were studied. Compared with patients who drink twice per week (reference group), patients who drink once per week showed the lowest risk [hazard ratio (HR) 0.933, 95% confidence interval (CI) 0.916-0.950] and those who drink everyday had the highest risk for new-onset AF (HR 1.412, 95% CI 1.373-1.453), respectively. However, the amount of alcohol intake per drinking session did not present any clear association with new-onset AF. Regardless of whether weekly alcohol intake exceeded 210 g, the frequency of drinking was significantly associated with the risk of new-onset AF. In contrast, when patients were stratified by weekly alcohol intake (210 g per week), those who drink large amounts of alcohol per drinking session showed a lower risk of new-onset AF.

CONCLUSION

Frequent drinking and amount of alcohol consumption per week were significant risk factors for new-onset AF, whereas the amount of alcohol consumed per each drinking session was not an independent risk factor. Avoiding the habit of consuming a low but frequent amount of alcohol might therefore be important to prevent AF.

Aldehyde Dehydrogenase 2 Ameliorates Chronic Alcohol Consumption-Induced Atrial Fibrillation through Detoxification of 4-HNE

Aldehyde dehydrogenase 2 (ALDH2) is an enzyme that detoxifies reactive oxygen species (ROS)-generated aldehyde adducts such as 4-hydroxy-trans-2-nonenal (4-HNE). Previous meta-analyses have shown an increase in the risk of atrial fibrillation (AF) in patients with chronic alcohol consumption. ALDH2*2, a common dysfunctional polymorphism in the ALDH2 gene, has been linked to an increased risk of cancer and heart disease. We tested the effect of ALDH2 deficiency on alcohol-induced AF in a murine model of chronic-binge ethanol feeding, with ALDH2*2 knock-in (KI) mice generated by a CRISPR/CAS9 system. In addition, right atrial appendages were obtained from eight patients with AF undergoing open heart surgery. The results showed that burst atrial pacing induced a greater susceptibility to AF in ALDH2*2 KI mice exposed to chronic ethanol intoxication than in wild-type mice, resulting from a higher degree of 4-HNE accumulation and collagen deposition in their atria. Alda-1 attenuated transforming growth factor beta 1 (TGF-β1) expression and collagen deposition in the atria and reduced AF inducibility. Patients with AF and the ALDH2*2 allele exhibited greater oxidative stress and substrate remodeling in their atria than non-carriers. In conclusion, ALDH2 deficiency may increase the risk of chronic alcohol and tachypacing-induced AF through the accumulation of 4-HNE and increased ROS production.

The Impact of Alcohol Intake on Atrial Fibrillation

PURPOSE OF REVIEW

To evaluate (1) the impact of acute and habitual alcohol consumption on atrial fibrillation (AF) and atrial remodeling and (2) the role of alcohol reduction and/or abstinence in the primary and secondary prevention of AF.

RECENT FINDINGS

Acute alcohol consumption appears to be a common AF trigger, with animal and human studies demonstrating changes in electrophysiological parameters, autonomic tone, and cellular properties expected to promote AF. Habitual consumption is associated with adverse atrial remodeling, higher risk of incident AF, and AF recurrence. Randomized data suggest that reduction in excessive alcohol consumption may reduce the risk of recurrent AF episodes and AF burden. Alcohol is an increasingly recognized risk factor for both new onset AF and discrete AF episodes. Excessive consumption should be avoided for primary and secondary prevention of AF.

No association between alcohol consumption and risk of atrial fibrillation: A two-sample Mendelian randomization study

BACKGROUND AND AIMS

Although many observational studies have suggested that alcohol intake was associated with incident atrial fibrillation (AF), controversy remains. This study aimed to examine the causal association of alcohol intake with the risk of AF.

METHODS AND RESULTS

Two-sample Mendelian randomization (MR) analysis was performed to estimate the causal effects of alcohol consumption, alcohol dependence, or alcohol use disorder identification test (AUDIT) scores on AF. Summary data on single nucleotide polymorphisms (SNPs) associated with AF were obtained from a genome-wide association study (GWAS) with up to 1,030,836 participants. The fixed- and random-effect inverse-variance weighted (IVW) methods were used to calculate the overall causal effects. MR analysis revealed nonsignificant association of genetically predicted alcohol consumption with risk of AF using fixed- and random-effect IVW approaches (odds ratio (OR) [95% confidence interval (CI)] = 1.004 [0.796-1.266], P = 0.975; OR [95% CI] = 1.004 [0.766-1.315], P = 0.979). Genetically predicted alcohol dependence was also not causally associated with AF in the fixed- and random-effect IVW analyses (OR [95% CI] = 1.012 [0.978-1.048], P = 0.490; OR [95% CI] = 1.012 [0.991-1.034], P = 0.260). There was no significantly causal association between AUDIT and AF in the fixed- and random-effect IVW analyses (OR [95% CI] = 0.889 [0.433-1.822], P = 0.748; OR [95% CI] = 0.889 [0.309-2.555], P = 0.827). Sensitivity analyses indicated no evidence of pleiotropy and heterogeneity in statistical models.

CONCLUSIONS

This MR study did not find evidence of a causal association between alcohol intake and AF.

Novel beta-blocker pretreatment prevents alcohol-induced atrial fibrillation in a rat model

Background

A case report published in 2019 described a patient who presented with difficult-to-manage atrial fibrillation (AF) that consistently was associated with alcohol consumption. After the patient did not respond to drug therapy, a novel beta-blocker (BB) pretreatment regimen initiated immediately before alcohol consumption successfully prevented AF occurrence.

Objective

The purpose of this study was to test the hypothesis that a novel prophylactic BB therapy given before alcohol consumption could prevent AF in a rat model.

Methods

An alcohol-induced AF model was developed in adult Sprague-Dawley rats of both sexes by administering alcohol (2 g/kg intraperitoneal [IP]) once every other day for a total of 4 times. Three groups were enrolled: alcohol (EtOH; n = 10); alcohol plus BB (metoprolol 50 mg/kg IP) pretreatment (EtOH+BB; n = 10); and control (n = 9). Cardiac function (assessed by echocardiography and left ventricular hemodynamics) and in vivo atrial electrophysiology and AF inducibility tests were performed 24 hours after the last injection.

Results

All but 1 rat completed the study. Alcohol exposure did not significantly impact cardiac function and the atrial effective refractory period. However, alcohol exposure significantly increased AF inducibility [median (first and third quartile [Q1–Q3]) 0% (0%–0%) in control vs 60% (25%–100%) in the EtOH group; P <.05] and AF duration [0 second (0–0 second) in control vs 0.81 second (0.24–3.67 seconds) in the EtOH group; P <.05]. Compared to the EtOH group, the EtOH+BB group had significantly reduced AF inducibility [0% (0%–22.5%); P <.05] and duration [0 second (0–0.2 second); P <.05].

Conclusion

Metoprolol pretreatment before alcohol administration significantly decreased AF induction in rats. These findings suggest that BB pretreatment is a promising prophylaxis regimen for alcohol-induced AF.

Alcohol consumption and risk of incident atrial fibrillation: A population-based cohort study

AIMS

Atrial fibrillation (AF) is a common tachyarrhythmia. High alcohol consumption is associated with increased AF risk. It remains unclear whether lower levels of alcohol consumption are also associated with AF risk, and whether the association differs between men and women. In this study, we investigated the association between low to moderate levels of alcohol consumption and AF risk in men and women.

METHODS

We performed a population-based cohort study of 109,230 health examination participants in northern Sweden. Data regarding alcohol intake were obtained using a questionnaire administered at the health examination. Incident AF cases were identified from the Swedish National Patient Registry.

RESULTS

AF was diagnosed in 5,230 individuals during a total follow-up of 1,484,547 person-years. Among men, AF risk increased over quartiles of weekly alcohol consumption (P for trend 0.001). Men with alcohol consumption in the highest quartile (≥4.83 standard drinks [each drink containing 12 gs of ethanol] per week; SDW) had a HR of 1.21 (95% CI 1.09-1.34) for AF compared to men in the lowest quartile (<0.90 SDW). In men, problem drinking was also associated with an increased AF risk (HR: 1.24; 95% CI: 1.10-1.39). Among women, AF risk was not significantly associated with alcohol consumption (P for trend 0.09 for decreasing risk of AF over quartiles of weekly alcohol consumption) or problem drinking (HR: 1.00; 95% CI 0.70-1.42).

CONCLUSION

Self-reported alcohol consumption and problem drinking were associated with an increased risk of AF among men, but not in women.

Atrial fibrillation risk factor management with a plant-based diet: A review

Atrial fibrillation is the most prevalent cardiac arrhythmia in the clinical setting affecting approximately 34 million individuals worldwide. The disease is associated with a significant burden of morbidity and mortality resulting from stroke, heart failure, and acute coronary syndrome. Atrial fibrillation is now a major public health problem with tremendous implications on the economy and the world's healthcare systems. Numerous risk factors and clinical conditions that are associated with the development and progression of atrial fibrillation have been identified in the past. Within the last decades, a shift in awareness toward modifiable conditions has been observed and risk factor management has gained significant momentum. In light of this, dietary approaches are of paramount importance. Whole-food plant-based diets emphasizing grains, legumes, vegetables, fruits and nuts and excluding most (or all) animal products have recently experienced a significantly increased interest. The purpose of this review is to present evidence suggestive of a plant-based diet being a valuable tool in atrial fibrillation risk factor management. The effects of a plant-based diet on both established and emerging risk factors, such as inflammation and subclinical atherosclerosis, are reviewed in this article. A special focus is put on cardiovascular and metabolic risk factors including hypertension, coronary artery disease, diabetes, and obesity.

Alcohol use disorders and the heart

Alcohol use is an important preventable and modifiable cause of non-communicable disease, and has complex effects on the cardiovascular system that vary with dose. Observational and prospective studies have consistently shown a lower risk of cardiovascular and all-cause mortality in people with low levels of alcohol consumption when compared to abstainers (the 'J'-shaped curve). Maximum potential benefit occurs at 0.5 to one standard drinks (7-14 g pure ethanol) per day for women (18% lower all-cause mortality, 95% confidence interval (CI) = 13-22%) and one to two standard drinks (14-28 g ethanol) per day for men (17% lower all-cause mortality, 95% CI = 15-19%). However, this evidence is contested, and overall the detrimental effects of alcohol far outweigh the beneficial effects, with the risk of premature mortality increasing steadily after an average consumption of 10 g ethanol/day. Blood pressure (BP) is increased by regular alcohol consumption in a dose-dependent manner, with a relative risk for hypertension (systolic BP > 140 mm Hg or diastolic > 90 mm Hg) of 1.7 for 50 g ethanol/day and 2.5 at 100 g/day. Important reductions in BP readings can be expected after as little as 1 month of abstinence from alcohol. Heavy alcohol consumption in a binge pattern is associated with the development of acute cardiac arrhythmia, even in people with normal heart function. Atrial fibrillation is the most common arrhythmia associated with chronic high-volume alcohol intake, and above 14 g alcohol/day the relative risk increases 10% for every extra standard drink (14 g ethanol). Ethanol and its metabolites have toxic effects on cardiac myocytes, and alcoholic cardiomyopathy (ACM) accounts for a third of all cases of non-ischaemic dilated cardiomyopathy. Screening people drinking alcohol above low-volume levels and delivering a brief intervention may prevent the development of cardiovascular complications. Although people with established cardiovascular disease show improved outcomes with a reduction to low-volume alcohol consumption, there is no safe amount of alcohol to drink and patients with ACM should aim for abstinence in order to optimize medical treatment.

Alcohol and incident atrial fibrillation - A systematic review and meta-analysis

BACKGROUND

Whilst high levels of alcohol consumption are known to be associated with atrial fibrillation (AF), it is unclear if any level of alcohol consumption can be recommended to prevent the onset of the condition. The aim of this review is to characterise the association between chronic alcohol intake and incident AF.

METHODS AND RESULTS

Electronic literature searches were undertaken using PubMed and Embase databases up to 1 February 2016 to identify studies examining the impact of alcohol on the risk of incident AF. Prospective studies reporting on at least three levels of alcohol intake and published in English were eligible for inclusion. Studies of a retrospective or case control design were excluded. The primary study outcome was development of incident AF. Consistent with previous studies, high levels of alcohol intake were associated with an increased incident AF risk (HR 1.34, 95% CI 1.20-1.49, p<0.001). Moderate levels of alcohol intake were associated with a heightened AF risk in males (HR 1.26, 95% CI 1.04-1.54, p=0.02) but not females (HR 1.03, 95% CI 0.86-1.25, p=0.74). Low alcohol intake, of up to 1 standard drink (SD) per day, was not associated with AF development (HR 0.95, 95% CI 0.85-1.06, p=0.37).

CONCLUSIONS

Low levels of alcohol intake are not associated with the development of AF. Gender differences exist in the association between moderate alcohol intake and AF with males demonstrating greater increases in risk, whilst high alcohol intake is associated with a heightened AF risk across both genders.

Does Moderate Drinking Increase the Risk of Atrial Fibrillation? The Norwegian HUNT (Nord-Trøndelag Health) Study

BACKGROUND

Compelling evidence suggests that excessive alcohol consumption increases the risk of atrial fibrillation (AF), but the effect of light-moderate alcohol consumption is less certain. We investigated the association between alcohol consumption within recommended limits and AF risk in a light-drinking population.

METHODS AND RESULTS

Among 47 002 participants with information on alcohol consumption in a population-based cohort study in Norway, conducted from October 2006 to June 2008, 1697 validated AF diagnoses were registered during the 8 years of follow-up. We used Cox proportional hazard models with fractional polynomials to analyze the association between alcohol intake and AF. Population attributable risk for drinking within the recommended limit (ie, at most 1 drink per day for women and 2 drinks per day for men without risky drinking) compared with nondrinking was also calculated. The average alcohol intake was 3.8±4.8 g/d. The adjusted hazard ratio for AF was 1.38 (95% confidence interval, 1.06-1.80) when we compared participants consuming >7 drinks per week with abstainers. When we modeled the quantity of alcohol intake as a continuous variable, the risk increased in a curvilinear manner. It was higher with heavier alcohol intake, but there was virtually no association at <1 drink per day for women and <2 drinks per day for men in the absence of risky drinking. The population attributable risk among nonrisky drinkers was 0.07% (95% confidence interval, -0.01% to 0.13%).

CONCLUSIONS

Although alcohol consumption was associated with a curvilinearly increasing risk of AF in general, the attributable risk of alcohol consumption within recommended limits among participants without binge or problem drinking was negligible in this population.

Moderate Alcohol Consumption Is Associated With Lower Risk for Heart Failure But Not Atrial Fibrillation

OBJECTIVES

The aim of this study was to assess the hypothesis that alcohol consumption is associated with onset of atrial fibrillation (AF) and/or heart failure (HF).

BACKGROUND

The connection between ethanol intake and AF or HF remains controversial.

METHODS

The study population was 22,824 AF- or HF-free subjects (48% men, age ≥35 years) randomly recruited from the general population included in the Moli-sani study, for whom complete data on HF, AF, and alcohol consumption were available. The cohort was followed up to December 31, 2015, for a median of 8.2 years (183,912 person-years). Incident cases were identified through linkage to the Molise regional archive of hospital discharges. Hazard ratios were calculated using Cox proportional hazard models and cubic spline regression.

RESULTS

A total of 943 incident cases of HF and 554 of AF were identified. In comparison with never drinkers, both former and occasional drinkers showed comparable risk for developing HF. Drinking alcohol in the range of 1 to 4 drinks/day was associated with a lower risk for HF, with a 22% maximum risk reduction at 20 g/day, independent of common confounders. In contrast, no association of alcohol consumption with onset of AF was observed. Very similar results were obtained after restriction of the analyses to regular or only wine drinkers or according to sex, age, social status, or adherence to the Mediterranean diet.

CONCLUSIONS

Consumption of alcohol in moderation was associated with a lower incidence of HF but not with development of AF.

The association between pro-arrhythmic agents and aortic stenosis in young adults: is it sufficient to clarify the sudden unexpected deaths?

Most young patients with mild-to-moderate aortic stenosis show no symptoms, and sudden death appears only occasionally. We hypothesised that malignant ventricular arrhythmias could be responsible for the high incidence of sudden death in such patients. If multiple factors such as asymptomatic aortic stenosis in association with arrhythmia-provoking agents are involved, could it be sufficient to account for sudden unexpected death? In this study, eight cases of sudden death in young adults, with ages ranging from 22 to 36 years, who had never reported any symptoms that could be related to aortic stenosis, were investigated. Full autopsies were performed, and congenital aortic stenosis in all eight cases was confirmed. DNA testing for channelopathies was negative. Comprehensive toxicological analyses found an electrolyte imbalance, or non-toxic concentrations of amitriptyline, terfenadine, caffeine, and ethanol. Collectively, these results suggest that congenital asymptomatic aortic stenosis without cardiac hypertrophy in young adults is not sufficient to cause sudden death merely on its own; rather, an additional provoking factor is necessary. According to our findings, the provoking factor may be a state of physical or emotional stress, a state of electrolyte imbalance, or even taking a therapeutic dose of a particular drug.

Alcohol and Atrial Fibrillation: A Sobering Review

Alcohol is popular in Western culture, supported by a perception that modest intake is cardioprotective. However, excessive drinking has detrimental implications for cardiovascular disease. Atrial fibrillation (AF) following an alcohol binge or the "holiday heart syndrome" is well characterized. However, more modest levels of alcohol intake on a regular basis may also increase the risk of AF. The pathophysiological mechanisms responsible for the relationship between alcohol and AF may include direct toxicity and alcohol's contribution to obesity, sleep-disordered breathing, and hypertension. We aim to provide a comprehensive review of the epidemiology and pathophysiology by which alcohol may be responsible for AF and determine whether alcohol abstinence is required for patients with AF.

Alcohol and cardiovascular disease in the geriatric population

There has been little focus on the effects of alcohol on the elderly. Although the cardiovascular benefits of moderate alcohol consumption could be of the greatest benefit in this group, so might be the detrimental effects of abuse. In this article, we review available data on the effects of alcohol consumption on cardiovascular disease, cardiomyopathy, arrhythmias, hypertension, and vascular function in older adults. Alcohol consumption has increased in the US population age 65 years and older in the last decade, as has monthly heavy episodic drinking in older alcohol consumers. Studies of alcohol consumption in older subjects suggest that consumption in moderation does not increase the risk of heart failure, hypertension, or atrial arrhythmias, and may in fact improve vascular function and reduce cardiovascular disease events. As in younger subjects, heavy consumption, or abuse of alcohol, negates any potential protective cardiovascular effects, increasing the incidence of heart failure and hypertension. Although alcohol consumed in moderation does not appear harmful in the elderly population, heavier consumption exacerbates hypertension and increases the incidence of heart failure.

Atrial Flutter, Typical and Atypical: A Review

Clinical electrophysiology has made the traditional classification of rapid atrial rhythms into flutter and tachycardia of little clinical use. Electrophysiological studies have defined multiple mechanisms of tachycardia, both re-entrant and focal, with varying ECG morphologies and rates, authenticated by the results of catheter ablation of the focal triggers or critical isthmuses of re-entry circuits. In patients without a history of heart disease, cardiac surgery or catheter ablation, typical flutter ECG remains predictive of a right atrial re-entry circuit dependent on the inferior vena cava-tricuspid isthmus that can be very effectively treated by ablation, although late incidence of atrial fibrillation remains a problem. Secondary prevention, based on the treatment of associated atrial fibrillation risk factors, is emerging as a therapeutic option. In patients subjected to cardiac surgery or catheter ablation for the treatment of atrial fibrillation or showing atypical ECG patterns, macro-re-entrant and focal tachycardia mechanisms can be very complex and electrophysiological studies are necessary to guide ablation treatment in poorly tolerated cases.

Impact of Alcohol Consumption on the Outcome of Catheter Ablation in Patients With Paroxysmal Atrial Fibrillation

BACKGROUND

Although several studies have reported an association between atrial fibrillation (AF) and alcohol, the impact of alcohol consumption on the outcome after catheter ablation (CA) for AF has not been discussed. We aimed to elucidate the effect of alcohol consumption on the outcome of CA for paroxysmal AF.

METHODS AND RESULTS

We examined 1361 consecutive patients with paroxysmal AF (mean age, 61±11 years, 334 women) who underwent CA, including 623 (45.8%) patients who consumed alcohol. The clinical characteristics and outcomes of CA were compared between patients who did and did not consume alcohol. No significant differences were seen in the left atrial size, duration of AF history, and incidence of nonpulmonary vein foci between 2 groups (P=NS). Although the AF recurrence-free rate after the initial CA was higher in patients who did not consume alcohol (261/623 [41.9%] versus 252/738 [34.1%]; mean follow-up, 44.4±30.7 months; P=0.003), the outcome after the final CA was similar between 2 groups (patients who consumed alcohol: 111/628 [17.7%] versus patients who did not consume alcohol: 138/738 [18.7%]; mean follow-up, 53.1±25.8 months; P=0.67). The frequency (hazard ratio 1.07 per 1 day/week increase, CI 1.00-1.15, P=0.04) of alcohol consumption was significantly associated with AF recurrence after CA.

CONCLUSIONS

The frequency of alcohol consumption may be associated with AF recurrence after the initial CA for paroxysmal AF, but it may not affect the outcome after the final CA.

Exome sequencing of a family with lone, autosomal dominant atrial flutter identifies a rare variation in ABCB4 significantly enriched in cases

Background

Lone atrial flutter (AFL) and atrial fibrillation (AF) are common and sometimes consequential cardiac conduction disorders with a strong heritability, as underlined by recent genome-wide association studies that identified genetic modifiers. Follow-up family-based genetic analysis also identified Mendelian transmission of disease alleles. Three affected members were exome-sequenced for the identification of potential causative mutations, which were subsequently validated by direct sequencing in the other 3 affected members. Taqman assay was then used to confirm the role of any mutation in an independent population of sporadic lone AFL/AF cases.

Results

The family cluster analysis provided evidence of genetic inheritance of AFL in the family via autosomal dominant transmission. The exome-sequencing of 3 family members identified 7 potential mutations: of these, rs58238559, a rare missense genetic variant in the ATP-binding cassette sub-family B, member 4 (ABCB4) gene was carried by all affected members. Further analysis of 82 subjects with sporadic lone AF, 63 subjects with sporadic lone AFL, and 673 controls revealed that the allele frequency for this variation was significantly higher in cases than in the controls (0.05 vs. 0.01; OR = 3.73; 95% CI = 1.16–11.49; P = 0.013).

Conclusions

rs58238559 in ABCB4 is a rare missense variant with a significant effect on the development of AFL/AF.

Electronic supplementary material

The online version of this article (doi:10.1186/s12863-015-0177-0) contains supplementary material, which is available to authorized users.

Risk factors for atrial fibrillation in patients with normal versus dilated left atrium (from the Atherosclerosis Risk in Communities Study)

Epidemiological data are limited regarding risk factors of atrial fibrillation (AF) in patients with normal-sized left atria (LA). We evaluated whether traditional risk factors of AF differ between patients with normal-sized and dilated LA. This is a cross sectional study of community-dwelling participants of the Atherosclerosis Risk in Communities study. LA volume index was measured by 2-dimensional echocardiography. LA volume index ≥29 mm(3)/m(2) defined dilated LA. Prevalent AF was defined by electrocardiogram and hospital discharge International Classification of Diseases-9 codes. Multivariate adjusted logistic regression analysis was used to examine whether magnitude of association of risk factors with AF differ by LA cavity size. Interaction of risk factors by LA cavity size was evaluated to determine significance of these differential associations. Of 5,496 participants (mean age 75 ± 5 years, women 58%), 1,230 participants (22%) had dilated LA. The prevalence of AF was 11% in patients with normal-sized LA and 15% in patients with dilated LA. Age >75 years (odds ratio [OR] 1.87, 95% confidence interval [CI] 1.49 to 2.35, interaction p = 0.12) and heart failure (OR 5.43, 95% CI 3.77 to 7.87, interaction p = 0.10) were stronger risk factors for AF in normal-sized LA than dilated LA. Female gender (OR 1.67, 95% CI 1.01 to 2.77, interaction p = 0.09), weight (OR 1.32, 95% CI 1.02 to 1.71, interaction p = 0.19), and alcohol use (OR 1.61, 95% CI 1.08 to 2.41, interaction p = 0.004) were stronger risk factors for AF in patients with dilated LA than normal-sized LA. In conclusion, risk factors of AF may differ by left ventricular cavity size.

Alcohol consumption and risk of atrial fibrillation: a prospective study and dose-response meta-analysis

BACKGROUND

Although high alcohol consumption has been associated with increased risk of atrial fibrillation (AF), the role of light to moderate drinking remains unclear.

OBJECTIVES

The study sought to investigate the association between alcohol consumption and AF risk in a prospective study of Swedish men and women and to conduct a meta-analysis of prospective studies to summarize available evidence.

METHODS

We followed 79,019 men and women who, at baseline, were free from AF and had completed a questionnaire about alcohol consumption and other risk factors for chronic diseases. Incident AF cases were ascertained by linkage to the Swedish Inpatient Register. For the meta-analysis, studies were identified by searching PubMed through January 10, 2014, and by reviewing references of pertinent publications. Study-specific relative risks (RRs) were combined using a random effects model.

RESULTS

Over 859,420 person-years of follow-up (1998 to 2009), 7,245 incident AF cases were identified in our own cohort study. The association between alcohol consumption and AF did not differ by sex (p for interaction = 0.74). Compared with current drinkers of <1 drink/week (12 g alcohol/drink), the multivariable RRs of AF were 1.01 (95% confidence interval [CI]: 0.94 to 1.09) for 1 to 6 drinks/week, 1.07 (95% CI: 0.98 to 1.17) for 7 to 14 drinks/week, 1.14 (95% CI: 1.01 to 1.28) for 15 to 21 drinks/week, and 1.39 (95% CI: 1.22 to 1.58) for >21 drinks/week. Results were similar after excluding binge drinkers. In a meta-analysis of 7 prospective studies, including 12,554 AF cases, the RRs were 1.08 (95% CI: 1.06 to 1.10) for 1 drink/day, 1.17 (95% CI: 1.13 to 1.21) for 2 drinks/day, 1.26 (95% CI: 1.19 to 1.33) for 3 drinks/day, 1.36 (95% CI: 1.27 to 1.46) for 4 drinks/day, and 1.47 (95% CI: 1.34 to 1.61) for 5 drinks/day, compared with nondrinkers.

CONCLUSIONS

These findings indicate that alcohol consumption, even at moderate intakes, is a risk factor for atrial fibrillation.

The QT interval and risk of incident atrial fibrillation

BACKGROUND

Abnormal atrial repolarization is important in the development of atrial fibrillation (AF), but no direct measurement is available in clinical medicine.

OBJECTIVE

To determine whether the QT interval, a marker of ventricular repolarization, could be used to predict incident AF.

METHODS

We examined a prolonged QT interval corrected by using the Framingham formula (QT(Fram)) as a predictor of incident AF in the Atherosclerosis Risk in Communities (ARIC) study. The Cardiovascular Health Study (CHS) and Health, Aging, and Body Composition (ABC) study were used for validation. Secondary predictors included QT duration as a continuous variable, a short QT interval, and QT intervals corrected by using other formulas.

RESULTS

Among 14,538 ARIC study participants, a prolonged QT(Fram) predicted a roughly 2-fold increased risk of AF (hazard ratio [HR] 2.05; 95% confidence interval [CI] 1.42-2.96; P < .001). No substantive attenuation was observed after adjustment for age, race, sex, study center, body mass index, hypertension, diabetes, coronary disease, and heart failure. The findings were validated in Cardiovascular Health Study and Health, Aging, and Body Composition study and were similar across various QT correction methods. Also in the ARIC study, each 10-ms increase in QT(Fram) was associated with an increased unadjusted (HR 1.14; 95% CI 1.10-1.17; P < .001) and adjusted (HR 1.11; 95% CI 1.07-1.14; P < .001) risk of AF. Findings regarding a short QT interval were inconsistent across cohorts.

CONCLUSIONS

A prolonged QT interval is associated with an increased risk of incident AF.

Comparison of Atrial Fibrillation in the Young versus That in the Elderly: A Review

The incidence and prevalence of atrial fibrillation (AF) are projected to increase significantly worldwide, imposing a significant burden on healthcare resources. The disease itself is extremely heterogeneous in its epidemiology, pathophysiology, and treatment options based on individual patient characteristics. Whilst ageing is well recognised to be an independent risk factor for the development of AF, this condition also affects the young in whom the condition is frequently symptomatic and troublesome. Traditional thinking suggests that the causal factors and pathogenesis of the condition in the young with structurally normal atria but electrophysiological "triggers" in the form of pulmonary vein ectopics leading to lone AF are in stark contrast to that in the elderly who have AF primarily due to an abnormal substrate consisting of fibrosed and dilated atria acting in concert with the pulmonary vein triggers. However, there can be exceptions to this rule as there is increasing evidence of structural and electrophysiological abnormalities in the atrial substrate in young patients with "lone AF," as well as elderly patients who present with idiopathic AF. These reports seem to be blurring the distinction in the pathophysiology of so-called idiopathic lone AF in the young versus that in the elderly. Moreover with availability of improved and modern investigational and diagnostic techniques, novel causes of AF are being reported thereby seemingly consigning the diagnosis of "lone AF" to a rather mythical existence. We shall also elucidate in this paper the differences seen in the epidemiology, causes, pathogenesis, and clinical features of AF in the young versus that seen in the elderly, thereby requiring clearly defined management strategies to tackle this arrhythmia and its associated consequences.

Recommendations regarding dietary intake and caffeine and alcohol consumption in patients with cardiac arrhythmias: what do you tell your patients to do or not to do?

OPINION STATEMENT

The etiology of arrhythmias including atrial fibrillation is multifactorial. Most arrhythmias are associated with comorbid illnesses like hypertension, diabetes, thyroid disease, or advanced age. Although it is tempting to blame a stimulant like caffeine as a trigger for arrhythmias, the literature does not support this idea. There is no real benefit to having patients with arrhythmias limit their caffeine intake. Caffeine is a vasoactive substance that also may promote the release of norepinephrine and epinephrine. However, acute ingestion of caffeine (as coffee or tea) does not cause atrial fibrillation. Even patients suffering a myocardial infarction do not have an increased incidence of ventricular or other arrhythmias after ingesting several cups of coffee. Large epidemiologic studies have also failed to find a connection between the amount of coffee/caffeine used and the development of arrhythmias. As such, it does not make sense to suggest that patients with palpitations, paroxysmal atrial fibrillation, or supraventricular tachycardia, abstain from caffeine use. Energy drinks are a new phenomenon on the beverage market, with 30-50 % of young adults and teens using them regularly. Energy drinks are loaded with caffeine, sugar, and other chemicals that can stimulate the cardiac system. There is an increasing body of mainly anecdotal case reports describing arrhythmias or even sudden death triggered by exercise plus using energy drinks. Clearly, there must be more study in this area, but it is wise to either limit or avoid their use in patients with arrhythmias. Moderate to heavy alcohol use seems to be associated with the development of atrial fibrillation. The term "holiday heart" was coined back in 1978, to describe patients who had atrial fibrillation following binge alcohol use. Thus, it is reasonable to recommend to patients with arrhythmias that they limit their alcohol use, although unfortunately this treatment will likely not completely resolve their arrhythmia.

Alcohol consumption and the risk of incident atrial fibrillation among people with cardiovascular disease

BACKGROUND

Moderate alcohol consumption may reduce cardiovascular events, but little is known about its effect on atrial fibrillation in people at high risk of such events. We examined the association between moderate alcohol consumption and the risk of incident atrial fibrillation among older adults with existing cardiovascular disease or diabetes.

METHODS

We analyzed data for 30 433 adults who participated in 2 large antihypertensive drug treatment trials and who had no atrial fibrillation at baseline. The patients were 55 years or older and had a history of cardiovascular disease or diabetes with end-organ damage. We classified levels of alcohol consumption according to median cut-off values for low, moderate and high intake based on guidelines used in various countries, and we defined binge drinking as more than 5 drinks a day. The primary outcome measure was incident atrial fibrillation.

RESULTS

A total of 2093 patients had incident atrial fibrillation. The age- and sex-standardized incidence rate per 1000 person-years was 14.5 among those with a low level of alcohol consumption, 17.3 among those with a moderate level and 20.8 among those with a high level. Compared with participants who had a low level of consumption, those with higher levels had an increased risk of incident atrial fibrillation (adjusted hazard ratio [HR] 1.14, 95% confidence interval [CI] 1.04-1.26, for moderate consumption; 1.32, 95% CI 0.97-1.80, for high consumption). Results were similar after we excluded binge drinkers. Among those with moderate alcohol consumption, binge drinkers had an increased risk of atrial fibrillation compared with non-binge drinkers (adjusted HR 1.29, 95% CI 1.02-1.62).

INTERPRETATION

Moderate to high alcohol intake was associated with an increased incidence of atrial fibrillation among people aged 55 or older with cardiovascular disease or diabetes. Among moderate drinkers, the effect of binge drinking on the risk of atrial fibrillation was similar to that of habitual heavy drinking.

Alcohol and vagal tone as triggers for paroxysmal atrial fibrillation

Alcohol and vagal activity may be important triggers for paroxysmal atrial fibrillation (PAF), but it remains unknown if these associations occur more often than would be expected by chance alone because of the lack of a comparator group in previous studies. We compared self-reported frequency of these triggers in patients with PAF to those with other supraventricular tachycardias (SVTs). Consecutive consenting patients presenting for electrophysiology procedures at a single university medical center underwent a structured interview regarding arrhythmia triggers. Two hundred twenty-three patients with a documented arrhythmia (133 with PAF and 90 with SVT) completed the survey. After multivariable adjustment, patients with PAF had a 4.42 greater odds (95% confidence interval [CI] 1.35 to 14.44) of reporting alcohol consumption (p = 0.014) and a 2.02 greater odds (95% CI 1.02 to 4.00) of reporting vagal activity (p = 0.044) as an arrhythmia trigger compared to patients with SVT. In patients with PAF, drinking primarily beer was associated with alcohol as a trigger (odds ratio [OR] 4.49, 95% CI 1.41 to 14.28, p = 0.011), whereas younger age (OR 0.68, 95% CI 0.49 to 0.95, p = 0.022) and a family history of AF (OR 5.73, 95% CI 1.21 to 27.23, p = 0.028) each were independently associated with having vagal activity provoke an episode. Patients with PAF and alcohol triggers were more likely to have vagal triggers (OR 10.32, 95% CI 1.05 to 101.42, p = 0.045). In conclusion, alcohol consumption and vagal activity elicit PAF significantly more often than SVT. Alcohol and vagal triggers often were found in the same patients with PAF, raising the possibility that alcohol may precipitate AF by vagal mechanisms.

The Estimated Risk of Atrial Fibrillation Related to Alcohol Consumption

The risk of acute heavy alcohol intake on the development of atrial fibrillation (AF), aka ?holiday heart syndrome?, has been well-described. However, whether chronic alcohol intake is also associated with increased risk of AF, or might even be protective as has been observed with other cardiac conditions, is more uncertain. A number of studies, from basic science to large cohort studies have been performed to analyze the association between alcohol and AF. Basic-level studies have found that alcohol causes changes in tissue electrophysiology, ion channels, and circulating hormones, which might promote development and maintenance of AF. Clinical studies have generally shown groups with the highest regular intake of alcohol to be at increased risk, with no association with more moderate use. However, these studies have not always accounted for other AF risk factors, been inconsistent in the assessment and validation of the quantity of alcohol consumed across populations, and been unable to completely separate drinking patterns from overall health of participants. As a result, solid conclusions about a threshold level for ?safe? chronic alcohol intake cannot be made with regard to AF risk, but it appears to be safe within currently recommended limits of 1 drink daily for women and 2 for men. In this review, we discuss these findings, limitations, and conclusions.

Alcohol consumption and risk of atrial fibrillation: a meta-analysis

OBJECTIVES

The purpose of this meta-analysis is to summarize the estimated risk of atrial fibrillation (AF) related to alcohol consumption.

BACKGROUND

Results from observational studies examining the relationship between alcohol consumption and AF are inconsistent.

METHODS

A systematic electronic search of Medline (January 1966 to December 2009) and Embase (January 1974 to December 2009) databases was conducted for studies using key words related to alcohol and AF. Studies were included if data on effect measures for AF associated with habitual alcohol intake were reported or could be calculated. The effect measures for AF for the highest versus lowest alcohol intake in individual studies were pooled with a variance-based method. Linear and spline regression analyses were conducted to quantify the relationship between alcohol intake and AF risk.

RESULTS

Fourteen eligible studies were included in this meta-analysis. The pooled estimate of AF for the highest versus the lowest alcohol intake was 1.51 (95% confidence interval: 1.31 to 1.74). A linear regression model showed that the pooled estimate for an increment of 10 g per day alcohol intake was 1.08 (95% confidence interval: 1.05 to 1.10; R(2) = 0.43, p < 0.001). A spline regression model also indicated that the AF risk increased with increasing levels of alcohol consumption.

CONCLUSIONS

Results of this meta-analysis suggest that not consuming alcohol is most favorable in terms of AF risk reduction.

Acute ingestion of alcohol and cardiac autonomic modulation in healthy volunteers

Arrhythmogenic effects of alcohol may be intermediated by its effects over heart rate variability (HRV). Most studies about the effects of alcohol over HRV were observational and did not explore the temporal influence of alcohol ingestion over autonomic modulation. The aim of this study was to verify if an acute ingestion of alcohol has a time-dependent influence over time-domain indices of HRV. The effect of the ingestion of 60 g of ethanol or placebo over autonomic modulation was compared in healthy men (35 per group), with 18-25 years of age, before and during 17 h after ingestion. Alcohol promoted a fall in the standard deviation of all normal R-R intervals, root mean square of successive differences, and percentage of pairs of adjacent R-R intervals differing by more than 50 ms and in two indices of the three-dimensional return map, by a period up to 10 h after the ingestion of alcohol, accompanied by an increase in heart rate. The indices returned to values similar of the control group 10 h after ingestion. The effects over HRV indices were attenuated by adjustment for heart rate. The ingestion of alcohol induces a broad cardiovascular adaptation secondary to vagal withdrawal and sympathetic activation that may be responsible for arrhythmogenic effects of alcohol ingestion.

Alcohol and arrhythmias: a comprehensive review

The use of alcohol as a social lubricant has been ubiquitous in human societies since ancient times. It has also long been recognized that alcohol produces undesirable cardiovascular effects, especially when imbibed in excess. Numerous investigators have noted a causal relationship between alcohol and arrhythmias, as well as sudden cardiac death. We have undertaken a comprehensive review of the literature on alcohol as a potential trigger for arrhythmias. We have reviewed the major epidemiological studies undertaken on this subject. We have also explored pathophysiological mechanisms that drive the arrythmogenic effects of alcohol. In conclusion, although there is definite proof in the literature to implicate alcohol as a culprit in arrhythmias, the relationship is complex.