Alcohol concentration determines the type of atrial arrhythmia induced in a porcine model of acute alcoholic intoxication

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.

Clinical and Structural Factors Affecting Ablation Outcomes in Atrial Fibrillation Patients - A Review

Catheter ablation is an effective and durable treatment option for patients with atrial fibrillation (AF). Ablation outcomes vary widely, with optimal results in patients with paroxysmal AF and diminishing results in patients with persistent or long-standing persistent AF. A number of clinical factors including obesity, hypertension, diabetes, obstructive sleep apnea, and alcohol use contribute to AF recurrence following ablation, likely through modulation of the atrial electroanatomic substrate. In this article, we review the clinical risk factors and the electro-anatomic features that contribute to AF recurrence in patients undergoing ablation for AF.

Extrahepatic Manifestations in Alcoholic Liver Disease

Though liver is the most commonly affected organ in patients with chronic and excessive intake of alcohol, no organ is immune to toxic effects of alcohol and patients with alcohol-related liver disease (ALD) can suffer from a wide list of extrahepatic manifestations involving gastrointestinal tract, central and peripheral nervous systems, cardio vascular system, musculo-skeletal system, disruption of nutritional status, endocrinological abnormalities, hematological abnormalities and immune dysfunction. These extrahepatic organ involvements are usually overlooked by hepatologists and physicians who are mostly focused on managing life threatening complications of ALD. As a result, there is delayed diagnosis, delay in the initiation of appropriate treatment and late referral to other specialists. Some of these manifestations are of utmost clinical importance (e.g. delirium tremans and Wernicke's encephalopathy) because an early diagnosis and treatment can lead to full recovery while delayed or no treatment can result in death. On the other hand, several extrahepatic manifestations are of prognostic significance (such as alcoholic cardiomyopathy and malignancies) in which there is an increased risk of morbidity and mortality. Hence, a clear understanding and awareness of the extrahepatic manifestations of ALD is quintessential for proper management of these patients.

Harmful Impact of Tobacco Smoking and Alcohol Consumption on the Atrial Myocardium

Tobacco smoking and alcohol consumption are widespread exposures that are legal and socially accepted in many societies. Both have been widely recognized as important risk factors for diseases in all vital organ systems including cardiovascular diseases, and with clinical manifestations that are associated with atrial dysfunction, so-called atrial cardiomyopathy, especially atrial fibrillation and stroke. The pathogenesis of atrial cardiomyopathy, atrial fibrillation, and stroke in context with smoking and alcohol consumption is complex and multifactorial, involving pathophysiological mechanisms, environmental, and societal aspects. This narrative review summarizes the current literature regarding alterations in the atrial myocardium that is associated with smoking and alcohol.

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.

Effect of the ALDH2 Variant on the Prevalence of Atrial Fibrillation in Habitual Drinkers

Background

Alcohol—a risk factor for atrial fibrillation (AF)—is metabolized by aldehyde dehydrogenase 2 (ALDH2). Dysfunctional alleles of ALDH2 (ALDH2-deficient variants) are prevalent among East Asians.

Objectives

Because the prevalence of AF is estimated to be high in ALDH2-deficient variant carriers, we investigated the correlation between AF and ALDH2-deficient variant carriers, including the association with habitual alcohol consumption.

Methods

A total of 656 consecutive patients were included in this investigation. ALDH2 genotypes were divided into ALDH2 homozygous wild-type (∗1/∗1), ALDH2 heterozygous-deficient allele (∗1/∗2), and ALDH2 homozygous-deficient allele (∗2/∗2). Multivariate analyses were applied to determine the correlation between ALDH2 genotype and AF.

Results

ALDH2∗1/∗2 and ALDH2∗2/∗2 carriers who were ALDH2-deficient variant carriers comprised 199 (30.3%) and 27 (4.1%) patients, respectively. Among these patients, the proportions of habitual alcohol consumption were 26.1% and 0%, respectively. Multivariate analysis revealed that ALDH2∗1/∗2 itself was not a risk factor for AF (odds ratio [OR]: 1.28; P = 0.21). However, habitual alcohol consumption in ALDH2∗1/∗2 carriers was an independent risk factor of AF (OR: 4.13; P = 0.001). Contrary to expectations, ALDH2∗2/∗2 itself had a lower incidence of AF among other risk factors (OR: 0.37; P = 0.03).

Conclusions

Although the ALDH2∗1/∗2 itself was not associated with AF, ALDH2∗1/∗2 carriers with habitual alcohol consumption could experience AF because of slow alcohol metabolism. In contrast, ALDH2∗2/∗2 itself had a lower incidence of AF. This might be related to the absence to habitual alcohol consumption in ALDH2∗2/∗2 carriers because of the negligible activity of ALDH2. Thus, abstaining from alcohol consumption might prevent the development of AF in patients who are ALDH2∗1/∗2 carriers.

Uric acid and incident atrial fibrillation of 14 years population-based cohort study: The Suita Study

BACKGROUND

Higher baseline uric acid (UA) was significantly associated with higher atrial fibrillation (AF) incidence in Japanese women. However, no prospective study is evident in the association between UA and incident AF in Japanese urban residents.

METHODS

A total of 6863 participants (aged 30-79 years; 47% men) without prior AF were followed for 13.9 years on average in the Suita Study. According to the UA categories, cox proportional hazards regression models were used to estimating the Hazard Ratios (HRs) and 95% confidence intervals (CIs) for incident AF.

RESULTS

During 95178 person-years of follow-up, we observed 311 cases of incident AF (204 cases in men and 107 cases in women). Compared to the subjects with UA of 4.0-4.9 mg/dL, multivariable-adjusted HR (95% CIs) of incident AF was 1.50 (1.01-2.25) (P = .047) for the subjects with UA ≥7.0 mg/dL.

CONCLUSION

High UA was associated with an increased risk for incident AF in the Japanese population.

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.

Animal models of arrhythmia: classic electrophysiology to genetically modified large animals

Arrhythmias are common and contribute substantially to cardiovascular morbidity and mortality. The underlying pathophysiology of arrhythmias is complex and remains incompletely understood, which explains why mostly only symptomatic therapy is available. The evaluation of the complex interplay between various cell types in the heart, including cardiomyocytes from the conduction system and the working myocardium, fibroblasts and cardiac immune cells, remains a major challenge in arrhythmia research because it can be investigated only in vivo. Various animal species have been used, and several disease models have been developed to study arrhythmias. Although every species is useful and might be ideal to study a specific hypothesis, we suggest a practical trio of animal models for future use: mice for genetic investigations, mechanistic evaluations or early studies to identify potential drug targets; rabbits for studies on ion channel function, repolarization or re-entrant arrhythmias; and pigs for preclinical translational studies to validate previous findings. In this Review, we provide a comprehensive overview of different models and currently used species for arrhythmia research, discuss their advantages and disadvantages and provide guidance for researchers who are considering performing in vivo studies.

Role of Stress Kinase JNK in Binge Alcohol-Evoked Atrial Arrhythmia

BACKGROUND

Excessive binge alcohol drinking has acute cardiac arrhythmogenic effects, including promotion of atrial fibrillation (AF), which underlies “Holiday Heart Syndrome.” The mechanism that couples binge alcohol abuse with AF susceptibility remains unclear. We previously reported stress-activated c-Jun N-terminal kinase (JNK) signaling contributes to AF development. This is interesting because JNK is implicated in alcohol-caused organ malfunction beyond the heart.

OBJECTIVES

The purpose of this study was to detail how JNK promotes binge alcohol-evoked susceptibility to AF.

METHODS

The authors found binge alcohol-exposure leads to activated JNK, specifically JNK2. Furthermore, binge alcohol induces AF (24- vs. 1.8-Hz burst pacing-induced episodes per attempt per animal), higher incidence of diastolic intracellular Ca²⁺activity (Ca²⁺waves, sarcoplasmic reticulum [SR] Ca²⁺leakage), and membrane voltage (V_m) and systolic Ca²⁺ release spatiotemporal heterogeneity (Δt_Vm-Ca). These changes were completely eliminated by JNK inhibition both in vivo and in vitro. calmodulin kinase II (CaMKII) is a proarrhythmic molecule known to drive SR Ca²⁺ mishandling.

RESULTS

The authors report for the first time that binge alcohol activates JNK2, which subsequently phosphorylates the CaMKII protein, enhancing CaMKII-driven SR Ca²⁺ mishandling. CaMKII inhibition eliminates binge alcohol-evoked arrhythmic activities.

CONCLUSIONS

Our studies demonstrate that binge alcohol exposure activates JNK2 in atria, which then drives CaMKII activation, prompting aberrant Ca²⁺ waves and, thus, enhanced susceptibility to atrial arrhythmia. Our results reveal a previously unrecognized form of alcohol-driven kinase-on-kinase proarrhythmic crosstalk. Atrial JNK2 function represents a potential novel therapeutic target to treat and/or prevent AF.

Mechanisms of cardiac ethanol toxicity and novel treatment options

Ethanol can acutely and chronically alter cardiomyocyte and whole-organ function in the heart. Importantly, ethanol acutely and chronically predisposes to arrhythmias, while chronic abuse can induce heart failure. However, the molecular mechanisms of ethanol toxicity in the heart are incompletely understood. In this review, we summarize the current mechanistic knowledge on cardiac ethanol toxicity, with a focus on druggable pathways. Ethanol effects on excitation-contraction coupling, oxidative stress, apoptosis, and cardiac metabolism, as well as effects of ethanol metabolites will be discussed. Important recent findings have been gained by investigation of acute ethanol effects. These include a renewed focus on reactive oxygen species (ROS) and induction of SR Ca²⁺ leak by CaMKII-mediated pathways downstream of ROS. Furthermore, a clinical outlook into potential novel treatment options is provided.

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.

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.

Complications of embolization

Embolization is a remarkably versatile procedure used in nearly all vascular and nonvascular systems to treat a wide range of pathology. The published literature is rich with studies demonstrating the enormous therapeutic potential offered by embolization procedures, and the possibilities continue to expand with the advent of new embolization agents and techniques. Unfortunately, with this variety and innovation comes a wide spectrum of potential complications, not always easy to classify and summarize, associated with embolization. This article reviews the procedures and associated complications of arterial and venous embolization procedures, organized by vascular distribution.

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.

Effects of alcohol on atrial fibrillation: myths and truths

Alcohol is the most consumed drug worldwide. Both acute and chronic alcohol use have been associated with cardiac arrhythmias, in particular atrial fibrillation, or so-called 'holiday heart syndrome'. Epidemiological, clinical and experimental studies have attempted to elucidate the mechanisms involved in this association. However, because most of these studies have shown conflicting results, the connection between ethanol and atrial arrhythmias remains controversial. Historical, epidemiological and pharmacological aspects of alcohol, as well as recent concepts on atrial fibrillation are reviewed. We then examine the literature and provide a critical point of view on the still elusive association between alcohol and atrial fibrillation.

Characterization of the Acute Cardiac Electrophysiologic Effects of Ethanol in Dogs

BACKGROUND

Alcohol has been related to atrial fibrillation (holiday heart syndrome), but its electrophysiologic actions remain unclear.

METHODS

We evaluated the effects of alcohol in 23 anesthetized dogs at baseline and after 2 cumulative intravenous doses of ethanol: first dose 1.5 ml/kg (plasma level 200 mg/dl); second dose 1.0 ml/kg (279 mg/dl). In 13 closed-chest dogs (5 with intact autonomic nervous system, 5 under combined autonomic blockade and 3 sham controls), electrophysiologic evaluation and monophasic action potential (MAP) recordings were undertaken in the right atrium and ventricle. In 5 additional dogs, open-chest biatrial epicardial mapping with 8 bipoles on Bachmann's bundle was undertaken. In the remaining 5 dogs, 2D echocardiograms and ultrastructural analysis were performed.

RESULTS

In closed-chest dogs with intact autonomic nervous system, ethanol had no effects on surface electrocardiogram and intracardiac variables. At a cycle length of 300 milliseconds, no effects were noted on atrial and ventricular refractoriness and on the right atrial MAP. These results were not altered by autonomic blockade. No changes occurred in sham controls. In open-chest dogs, ethanol did not affect inter-atrial conduction time, conduction velocity, and wavelength. Atrial arrhythmias were not induced in any dog, either at baseline or after ethanol. Histological and ultrastructural findings were normal but left ventricular (LV) ejection fraction decreased in treated dogs (77 vs. 73 vs. 66%; p = 0.04).

CONCLUSION

Ethanol at medium and high doses depresses LV systolic function but has no effects on atrial electrophysiological parameters. These findings suggest that acute alcoholic intoxication does not directly promote atrial arrhythmias.

Electrocardiographic findings after acute absinthe intoxication

A 29-year-old comatose patient was brought to Emergency Department with severe alcohol intoxication. No risk factors or cardiac abnormalities were documented. The analysis was negative for other drugs. Plasma electrolyte and cardiac enzymes were normal. The electrocardiogram showed Mobitz type-I atrioventricular block that developed to a rapid junctional rhythm. The patient was stabilized and recovered completely, electrocardiogram then showed sinus rhythm. He admitted important absinthe consumption. Although tachyarrhythmias are frequently developed in acute alcohol intoxication, bradyarrhythmias are exceptional in this context. We present a Wenckebach-type atrioventricular-block in severe alcohol intoxication with absinthe that developed to a rapid junctional rhythm, never described before.

Alcohol consumption and risk of atrial fibrillation in men and women: the Copenhagen City Heart Study

BACKGROUND

The relationship of the full range of alcohol consumption with risk of incident atrial fibrillation has been inconsistent in previous, mainly case-control studies.

METHODS AND RESULTS

In a prospective cohort study, we studied the association between self-reported alcohol use and incident atrial fibrillation among 16,415 women and men enrolled in the Copenhagen City Heart Study. We ascertained use of beer, wine, and spirits individually at up to 3 study visits with a structured questionnaire. We identified cases of atrial fibrillation by routine study ECGs and a validated nationwide registry of all hospitalizations. A total of 1071 cases occurred during follow-up. Among both women and men, alcohol consumption throughout the moderate range was not associated with risk of atrial fibrillation. However, consumption of 35 or more drinks per week among men was associated with a hazard ratio of 1.45 (95% CI 1.02 to 2.04); few women consumed this amount of alcohol. Approximately 5% of cases of atrial fibrillation among men were attributable to heavy alcohol use. Further adjustment for blood pressure and incident coronary heart disease and congestive heart failure did not attenuate the association (hazard ratio 1.63; 95% CI 1.15 to 2.31).

CONCLUSIONS

Heavy alcohol consumption is associated with a higher risk of atrial fibrillation, at least among men. This relationship does not appear to be related to the adverse effects of heavy drinking on coronary heart disease or blood pressure.

Comparative effects of thiopental and propofol on atrial vulnerability: electrophysiological study in a porcine model including acute alcoholic intoxication †

BACKGROUND

Atrial tachyarrhythmias (AT) frequently complicate the perioperative period. Alcohol intoxication is a recognized causative factor for dysrrhythmias. We studied the effects of propofol and thiopental on atrial electrophysiology and vulnerability to AT in a closed-chest porcine model in which AT are facilitated by ethanol.

METHODS

Thirty-eight pigs were randomly assigned to thiopental (T-group, n=19) or propofol (P-group n=19). All animals were assigned to undergo a right atrial electrical stimulation protocol (RASP) at baseline. Thirty pigs were assigned to undergo additional RASP during ethanol infusion, while the remaining eight were assigned to undergo additional RASP during saline infusion (control group). We analysed effective refractory period (ERP), and intra-atrial conduction interval (ICI) (between atrial sites 4 cm apart), at several cycle lengths (CL).

RESULTS

There were no significant differences at baseline. During ethanol infusion, propofol produced a greater rate-dependent decrease in excitability, manifested by a longer minimum paced CL with 1:1 atrial capture: 145 (11) vs 164 (27) ms in the T- and P-group, respectively (P=0.01). Propofol was associated with a greater rate-related slowing in conduction: difference between ICI at CL of 300 ms and ICI at minimum CL: 30 ms in P-group and 22 ms in T-group (P<0.03). In the P-group we observed a longer duration of induced arrhythmias (145 (131) vs 74 (91) s, P<0.03) and a higher proportion with atrial flutter (AFl) (76 vs 19%, P<0.001).

CONCLUSIONS

Propofol in this model was more arrhythmogenic than thiopental, as manifested by a longer duration of induced arrhythmias, particularly AFI.

Percutaneous Treatment of Low Flow Vascular Malformations

Low flow vascular malformations, especially venous and macrocystic lymphatic malformations, are effectively treated by percutaneous intralesional injection of sclerosant drugs, such as ethanol and detergent sclerosant drugs. Good to excellent results are possible in 75%-90% of patients who undergo serial sclerotherapy. Most adverse effects are manageable, but severe complications can result from the intravascular administration of ethanol. It is generally recommended that the treatment of vascular malformations be performed in a multidisciplinary setting by practitioners with appropriate training and support.

Bradycardia and sinus arrest during percutaneous ethanol injection therapy for hepatocellular carcinoma

BACKGROUND

Percutaneous ethanol injection (PEI) is an established method in the treatment of hepatocellular carcinoma (HCC) and considered a safe procedure, with severe complications occurring rarely. Cardiac arrhythmias have not been reported to date. Aim of the study was to investigate the occurrence of dysrhythmias during PEI.

PATIENTS AND METHODS

Twenty-six consecutive patients with inoperable HCC were included. During ultrasound-guided PEI with 95% ethanol, electrocardiogram (ECG) monitoring was performed before starting and continuously during PEI.

RESULTS

During PEI a significant reduction in mean heart rate (> 20%) was seen in 15 of 26 (58%) patients. In 11 of 26 patients (42%) occurrence of sinuatrial block (SAB) or atrioventricular block (AVB) was observed after a median time of 9 s (range 4-50) from the start of PEI with a median length of 24 s (range 12-480). Clinical symptoms were seen in two patients, including episodes of unconsciousness, seizure-like symptoms in both and a respiratory arrest during PEI in one patient, requiring mechanical ventilation. In four of 12 patients with repeat interventions, dysrhythmias were reproducible during monthly performed procedures. There was a significant association between the occurrence of SAB or AVB and the amount of instilled alcohol (P = 0.03) and post-PEI serum ethanol levels (P = 0.03).

CONCLUSIONS

Bradycardia and block formation occur frequently during PEI. These symptoms could be explained by a vasovagal reaction and/or the direct effect of ethanol on the sinus node or the right atrial conduction system. Ethanol dose is an important factor for the occurrence of SAB/AVB. ECG-monitoring seems mandatory during PEI. Prophylactic use of intravenously administered Atropine might be useful.

Serum ethanol levels after alcohol sclerotherapy of arteriovenous malformations

We analyzed the effects of several factors on the serum ethanol levels after alcohol sclerotherapy in the arteriovenous malformations (AVMs) retrospectively. Blood ethanol level, amounts of given alcohol, location of lesions, methods of flow control, and Doppler resistive index (RI) were analyzed. The results of linear regression analysis showed that the amount of alcohol administered was the predictor of serum ethanol level (r2=0.75, p<0.001). The average amount of injected alcohol was 0.89 mL/kg in the patients with the serum levels above the legal intoxication level (>80 mg/dL). Location of the lesions was not related with the serum ethanol level (p=0.643), and other variables such as forms of flow control and RI were not related to the serum ethanol level after controlling for injected amounts of alcohol (analysis of covariance). It is recommended to keep an eye on the possibility of intoxication when using the amounts of alcohol exceeding 0.89 mL/kg in the sclerotherapy of AVMs.

A theoretical model of the role of brain stem nuclei in alcohol-mediated arrhythmogenesis in older adults

Uncertainty about the mechanism of alcohol-mediated arrhythmogenesis and the effect of alcohol use on arrhythmic risk among older adults is an increasing concern in light of population aging and recent reports that moderate alcohol consumption may protect older adults against coronary artery disease. In this review, a theoretical model of the role of brain stem nuclei in alcohol-mediated arrhythmogenesis in older adults is developed. The model is based on the hypothesis that the effects of alcohol on central autonomic pathways of cardiac control may alter the threshold for alcohol-mediated arrhythmogenesis among older adults. Findings from multiple lines of research including cellular, electrophysiological, epidemiological, experimental, and clinical studies in human, animal, and in vitro models were synthesized in developing the model. Suggestions for future research on the topic of alcohol-mediated arrhythmogenesis in older adults are offered.

Serum ethanol levels in children and adults after ethanol embolization or sclerotherapy for vascular anomalies

PURPOSE

To evaluate the serum ethanol level in children and adults after ethanol embolization or sclerotherapy for vascular anomalies.

MATERIALS AND METHODS

Serum ethanol level was evaluated in 71 patients with vascular anomalies who underwent ethanol embolization, sclerotherapy, or both. Blood used to determine serum ethanol level was drawn at the end of each procedure.

RESULTS

The relationship between serum ethanol level and amount of ethanol administered was statistically significant. Results of stepwise linear regression analysis showed that the amount of ethanol administered (P <.001) and type of malformation (P =.02) were multivariate predictors of serum ethanol level. Results of logistic regression analysis revealed that the only uni- or multivariate predictor of legal intoxication was the amount of ethanol administered (P =.018). Five patients fulfilled the criteria for legal intoxication, and the mean amount of ethanol administered to these patients was 0.87 mL per kilogram of body weight +/- 0.18 (SD) (range, 0.55-0.99 mL/kg).

CONCLUSION

The volume of ethanol administered is the most reliable predictor of serum ethanol level and legal intoxication. Patients who receive up to 1.0 mL/kg ethanol during embolization or sclerotherapeutic procedures may have elevated serum ethanol levels that could put them at risk of respiratory depression, cardiac arrhythmias, seizures, rhabdomyolysis, and hypoglycemia.

Experimental models of atrial fibrillation/flutter

Animal models that mimic disease states or abnormal physiological events are tools that assist the investigator to understand the mechanism responsible for pathophysiological conditions. Atrial arrhythmias have intrigued physicians and cardiologists for decades. Thus the development of animal models for the study of atrial arrhythmias facilitate the investigation of these abnormal rhythms. Moreover, as our understanding of arrhythmias advances, so does the therapy designed to correct the condition, which ultimately improves the patient's clinical outcome. This manuscript describes a variety of animal models that have been utilized for the exploration of atrial arrhythmia generation and maintenance, as well as models used to evaluate the efficacy of putative antiarrhythmics agents.