Alcoholic cardiomyopathy. Concept of the disease and its treatment

The Evolution of Durable, Implantable Axial-Flow Rotary Blood Pumps

Left ventricular assist devices (LVADs) are increasingly used to treat patients with end-stage heart failure. Implantable LVADs were initially developed in the 1960s and 1970s. Because of technological constraints, early LVADs had limited durability (eg, membrane or valve failure) and poor biocompatibility (eg, driveline infections and high rates of hemolysis caused by high shear rates). As the technology has improved over the past 50 years, contemporary rotary LVADs have become smaller, more durable, and less likely to result in infection. A better understanding of hemodynamics and end-organ perfusion also has driven research into the enhanced functionality of rotary LVADs. This paper reviews from a historical perspective some of the most influential axial-flow rotary blood pumps to date, from benchtop conception to clinical implementation. The history of mechanical circulatory support devices includes improvements related to the mechanical, anatomical, and physiologic aspects of these devices. In addition, areas for further improvement are discussed, as are important future directions-such as the development of miniature and partial-support LVADs, which are less invasive because of their compact size. The ongoing development and optimization of these pumps may increase long-term LVAD use and promote early intervention in the treatment of patients with heart failure.

In Vivo Feasibility Study of an Intra-Atrial Blood Pump for Partial Support of the Left Ventricle

We are designing an intra-atrial pump (IAP) that will be affixed to the atrial septum and support the compromised left ventricle (LV) in patients with early-stage heart failure without harming the ventricular tissue. It will operate in parallel with the LV, drawing blood from the left atrium and unloading the LV. In previous hydraulic and hemodynamic studies, different blade geometries were tested for the IAP, and the hemodynamic results obtained using a mock circulatory loop showed that the IAP can successfully reduce end-diastolic volume and increase the total systemic flow rate. In the current study, we used a bovine model to validate the in vitro hemodynamic results and better understand how the IAP interacts with the cardiovascular system in vivo. Because this was the first study assessing the complete device in a living system, it was also necessary to determine the best manufacturing techniques and ideal sensor placements. In the bovine model, we were able to successfully implant the IAP across the atrial septum with the outflow graft connected to a peripheral artery. The implanted IAP was capable of providing partial support (1-3 L/min) in vivo. These results indicate that atrial cannulation is feasible and creates a beneficial hemodynamic environment.

Patients’ Alcohol Drinking Habits in General Practice: Prevention and Education

A survey of alcohol drinking habits using a questionnaire was conducted in a practice with 2 GPs and 4500 patients. Six hundred and thirty-two questionnaires were completed by all patients aged 15 and over attending the surgery during a three month period. Forty-five patients drinking in excess of 20 units of alcohol per week were identified, 22 of whom submitted to formal interview, examination, haematology, serum biochemistry and an education plan. When 20 of these were followed up after 3 months, 9 claimed to have significantly reduced their alcohol consumption and 10 remembered half or more of the ‘education plan’. As a result of the survey, drinking habits were recorded in the notes of 15% of the practice list and many associated medical problems were recognized for the first time.

Alcoholic cardiomyopathy : The result of dosage and individual predisposition

The individual amount of alcohol consumed acutely or chronically decides on harm or benefit to a person’s health. Available data suggest that one to two drinks in men and one drink in women will benefit the cardiovascular system over time, one drink being 17.6 ml 100 % alcohol. Moderate drinking can reduce the incidence and mortality of coronary artery disease, heart failure, diabetes, ischemic and hemorrhagic stroke. More than this amount can lead to alcoholic cardiomyopathy, which is defined as alcohol toxicity to the heart muscle itself by ethanol and its metabolites. Historical examples of interest are the Munich beer heart and the Tübingen wine heart. Associated with chronic alcohol abuse but having different etiologies are beriberi heart disease (vitamin B1 deficiency) and cardiac cirrhosis as hyperdynamic cardiomyopathies, arsenic poising in the Manchester beer epidemic, and cobalt intoxication in Quebec beer drinker’s disease. Chronic heavy alcohol abuse will also increase blood pressure and cause a downregulation of the immune system that could lead to increased susceptibility to infections, which in turn could add to the development of heart failure. Myocardial tissue analysis resembles idiopathic cardiomyopathy or chronic myocarditis. In the diagnostic work-up of alcoholic cardiomyopathy, the confirmation of alcohol abuse by carbohydrate deficient transferrin (CDT) and increased liver enzymes, and the involvement of the heart by markers of heart failure (e.g., NT-proBNP) and of necrosis (e.g., troponins or CKMb) is mandatory. Treatment of alcoholic cardiomyopathy consists of alcohol abstinence and heart failure medication.

Effects of alcohol on skeletal and cardiac muscle

The acute and chronic toxic effects of alcohol on skeletal and cardiac muscle are clinically important. Muscle weakness and atrophy are the main manifestations of skeletal myopathy, and arrhythmias and progressive left-ventricular dysfunction are those of cardiomyopathy. Most patients remain asymptomatic from these effects for a long time. Myocyte atrophy and death are the main pathological findings. A clear dose-related effect has been established with ethanol consumption, with gender and some specific gene polymorphisms being factors of increased susceptibility to alcohol-induced muscle damage. Pathogenic mechanisms are pleiotropic, the most relevant being disturbances in carbohydrate, protein, and energy cell turnover, signal transduction, and induction of apoptosis and gene dysregulation. Ethanol abstinence is the only effective treatment, although controlled drinking is useful in patients who do not achieve abstinence. Persistent high-dose consumption results in deterioration of muscle and heart function, with a high mortality due to arrhythmias and progression of heart failure.

Use of the transgenic mouse in models of AIDS cardiomyopathy

Heart disease in AIDS, particularly cardiomyopathy (CM), is an increasingly recognized clinical problem with as yet undefined pathogenetic mechanisms. Among the potential etiologies of AIDS CM are HIV-1 infection of cardiac myocytes and subsequent cardiac dysfunction, opportunistic infection, inflammatory reactions, cytokine effects, and cardiotoxicity of prescribed or illicit drugs. It seems probable that multiple factors may impact on the development of CM in AIDS. Transgenic mice (TG) are useful biological tools to explore mechanisms of cardiac function and disease. In AIDS models, TG offer novel ways to elucidate mechanisms of AIDS CM through combined in vivo and in vitro studies. With targeted and non-targeted TG, structural and functional effects of specific HIV-1 gene products on heart tissue may be addressed. The impact of environmental agents including therapeutics or cardiotoxins may also be defined. To address the complexity of AIDS CM using TG, an experimental approach has been employed in our laboratories to model the clinical condition. We utilize AIDS TG with generalized expression of HIV-1 gene products in CM models with combined antiretroviral regimens to define the cardiovascular effects of AIDS and its therapy on the structure and function of the murine heart. We are developing a series of cardiac specific TG bearing selected HIV-1 genes. These TG target the selected HIV-1 genes expressed in cardiac ventricular myocytes. Tissue-specific targeting of this type enables us to define structural and functional effects of specific HIV-1 gene products on the cardiac myocyte.

Alcoholic cardiomyopathy: is it dose-dependent?

Alcohol is a known myocardial depressant. In a dose-dependent fashion, one can show progressive decline in left ventricular systolic function. This observation has been used to implicate alcohol as a major cause of up to 30% of all dilated cardiomyopathies. However, it is not well recognized that there appears to be a biphasic cardiovascular effect based on the chronic dose of alcohol ingested. At low to moderate doses, studies suggest that alcohol has a favorable impact on cardiovascular outcomes. In other words, patients who have one to two glasses of alcohol per day have fewer myocardial infarctions and an improved survival. Large trials, such as the Physician Health Study, indicate that this benefit may be over wide ranges of doses, from one to seven glasses per week. When this is looked at in higher-risk diabetic patients, the benefit of low to moderate doses of alcohol persists. Together, this information suggests that low to moderate doses of alcohol improve cardiovascular risk, and this benefit may exceed the risk of hypertension or heart failure. It is equally important to recognize the serious down side to alcohol ingestion. At chronic high-dose intake of alcohol, there is a direct relationship to elevated blood pressure. Also, prolonged exposure to alcohol increases the likelihood of developing congestive heart failure. Combining the negative cardiovascular effects with potential danger to other organs, such as the liver, underscores the risk for high-dose alcohol. Therefore, there is a biphasic dose response to alcohol. At low to moderate doses, patients experience an overall cardiovascular benefit; it is only when a critical threshold is reached by high-dose alcohol that one observes the toxic effects. Patients on low to moderate ingestion of alcohol should be reassured, but those on high doses should be strongly encouraged to abstain due to potential toxic effects of alcohol.

Effects of alcohol on the heart

Some evidence suggests that light to moderate alcohol consumption protects against cardiovascular diseases. However, this cardioprotective effect of alcohol consumption in adults is absent at the population level. Approximately 20 to 30% of patients admitted to a hospital are alcohol abusers. In medical practice, it is essential that patients' levels of consumption are known because of the many adverse effects that might result in the course of routine care. Ethanol damage to the heart is evident if alcohol consumption exceeds 90 to 100 g/d. Heavy ethanol consumption leads to increased risk for sudden cardiac death and cardiac arrhythmias. In patients with coronary heart disease, alcohol use was associated with increased mortality. An early response to drinking was an increased ventricular wall thickness to diameter ratio, possibly proceeding with continuous drinking to alcoholic cardiomyopathy, which had a worse outcome compared with idiopathic dilative cardiomyopathy if drinking was not stopped or at least reduced (< 60 g/d). In the ICU, patients with chronic alcoholism have more cardiac complications postoperatively. These complications probably are caused by biventricular dysfunction, particularly with the occurrence of severe infections or septic shock, events that are three to four times more frequent among chronic alcoholics than occasional drinkers or nondrinkers. To prevent further complications from drinking and for long-term management of drinking, patients with alcohol abuse and heart failure should be treated in brief intervention and follow-up programs. Prognosis is good even in patients with New York Heart Association class IV heart failure caused by cardiomyopathy if complete abstinence is accomplished. Noncompliance to smoking and alcohol restrictions, which are amenable to change, dramatically increases the risk for hospital readmissions among patients with heart failure.

Cardiomyopathy in AIDS: a pathophysiological perspective

This report addresses issues of pathogenesis, pathophysiology, and epidemiology of an increasingly prevalent cardiomyopathy in acquired immunodeficiency syndrome (AIDS). As patient survival increases with more effective antiretroviral therapy, cardiomyopathy in AIDS will become more apparent. The interactions of cellular and organism factors in AIDS and their relationships to the development of cardiomyopathy are reviewed herein. Amongst the factors addressed in this review are: (1) comorbid conditions found with AIDS, (2) the role of inflammatory heart disease and cytokines in the development of AIDS cardiomyopathy, (3) the pathogenetic role of vascular cells and myocardial cells in the development of cardiomyopathy, (4) the role of myocardial retroviral infection in AIDS, and (5) the impact of toxicity from antiretroviral therapy on the development of cardiomyopathy. Because it is possible that more than 1 of these factors is present in a given patient inflicted with AIDS, a multifactorial pathogenesis in AIDS cardiomyopathy must be considered.

Medical consequences of substance abuse

Given the preceding review, differentiating the complications of parenteral drug use, HIV disease, and the toxicity of the drugs such as alcohol or cocaine may be a difficult matter for clinicians. The risk for coexisting morbidities is high. Thus, obtaining accurate and complete medical histories is of paramount importance. Drug-abuse treatment and follow-up medical care after an acute complication often involves multiple health care providers. The integration of primary prevention plans with the reinforcement of drug abstinence requires time, commitment, and the coordination of services. This integration should be a priority for individual patients as well as for public health planning.

Spectrum of alcohol-induced myocardial damage detected by indium-111-labeled monoclonal antimyosin antibodies

OBJECTIVES

We sought to determine the prevalence, intensity and evolving changes of myocardial damage detected by myocardial uptake of antimyosin antibodies in patients with alcohol-induced dilated cardiomyopathy, alcohol addicts attending a detoxification unit and healthy subjects with short-term alcohol consumption.

BACKGROUND

Evidence of alcohol-induced myocardial damage may be provided by myocardial uptake of indium-111-labeled monoclonal antimyosin antibodies. The spectrum of such damage in patients who are heavy drinkers (> 100 g for > 10 years), with or without cardiomyopathy, and the impact of short-term alcohol ingestion on antimyosin antibody uptake have not been adequately explored.

METHODS

One hundred twenty antimyosin studies were performed in 56 patients with dilated cardiomyopathy (group I), 15 alcohol addicts attending a detoxification unit (group II) and 6 volunteers for short-term alcohol ingestion (group III). Estimation of antibody uptake was calculated through a heart/lung ratio (HLR) (normal < 1.55).

RESULTS

The 56 patients in group I (54 men, 2 women; mean [+/-SD] age 46 +/- 11 years) had consumed 123 +/- 60 g/day of alcohol for 21 +/- 9 years, for a cumulative intake of 914 +/- 478 kg. Mean duration of symptoms was 46 +/- 49 months. Mean left ventricular end-diastolic diameter was 71 +/- 10 mm, and mean ejection fraction was 28 +/- 12%. No differences in New York Heart Association functional class, ventricular size or ejection fraction were noted between 28 active and 28 past consumers, except for the prevalence and intensity of antibody uptake (75% vs. 32%, p < 0.001) and HLR (1.75 +/- 0.26 vs. 1.49 +/- 0.17, p = 0.0001). In 19 patients in the active group restudied after alcohol withdrawal, antibody uptake decreased (from 1.76 +/- 0.17 to 1.55 +/- 0.19, p < 0.001), and ejection fraction improved (from 30 +/- 12% to 43 +/- 16%, (p < 0.001). No changes occurred in the 15 past consumers restudied. The 15 male patients in group II (mean age 36 +/- 4 years) had consumed 156 +/- 59 g/day for 17 +/- 5 years, for a cumulative alcohol intake of 978 +/- 537 kg, an amount similar to that in patients in group I, but antimyosin antibody uptake was detected in only 3 (20%) of 15 patients. None of six group III subjects developed antibody uptake after short-term ethanol ingestion. Despite the small sample size, the power to detect clinically relevant differences in most variables that did not reach statistical significance was amply sufficient.

CONCLUSIONS

In alcohol-induced dilated cardiomyopathy, alcohol withdrawal is associated with the reduction or disappearance of myocardial damage and improvement of function. The difference in prevalence of antimyosin antibody uptake in patients with and without cardiac disease who consume similar amounts of alcohol suggests the presence of those with different myocardial susceptibilities to alcohol. Short-term ethanol ingestion in healthy subjects does not induce detectable uptake of antimyosin antibodies.

Alcohol consumption and heart failure in hypertensives

Sixty hypertensives (30 with and 30 without heart failure, matched for age and sex) were studied and their alcohol consumption and its possible role in heart failure were assessed. The majority in each group belonged to the low socioeconomic class. On presentation, the mean systolic blood pressures were 176.7 +/- 29.7 and 198.8 +/- 29.8 mmHg and diastolic blood pressures 118 +/- 15 and 118.5 +/- 13.6 mmHg, respectively. In those known to be hypertensive before presentation to our unit, hypertension was first detected 4.88 +/- 3.8 and 4.40 +/- 3.3 years earlier in the heart failure and non-heart failure groups, respectively. Drug compliance was similarly poor in the two groups. Of all 12 drinkers in heart failure, 75% drank heavily, while only 18.2% (two of 11) of the non-heart failure drinkers drank heavily. Nine (30%) and two (6.7%) of the heart failure and the non-heart failure groups, respectively, took > or = 80 g of alcohol daily for at least 3 years (P < 0.02). Significantly more of the heart failure group were thiamine deficient, although the deficiency could not be directly attributed to alcohol. The odds ratio for heavy and moderate alcohol consumption was 5.9 and 0.9, respectively. Thus it is suggested that heavy alcohol consumption appears to be a major contributory factor to heart failure in these patients.

Effects of ethanol on the contractile function of the heart: a review

Chronic ethanol consumption leads to a number of alterations in the contractile function of the heart and is a leading cause of cardiomyopathy. Ethanol also has an acute negative inotropic effect mediated by direct interaction with cardiac muscle cells, although this action is often masked by indirect actions resulting from enhanced release of catecholamines in vivo. This article reviews the effects of ethanol on the contractile function of the heart. The specific targets affected by ethanol in cardiac muscle cells are discussed in terms of potential mechanisms underlying the depressions of contractility resulting from both acute and chronic actions of ethanol.

The risk of alcohol

We have reviewed 156 papers which provided sufficient information to relate individual alcohol consumption to risk for a variety of physical damage. Overall, there was evidence for a dose-response relationship between level of alcohol consumption and risk of harm for liver cirrhosis, cancers of the oropharynx, larynx, oesophagus, rectum (beer only), liver and breast, and blood pressure and stroke. An increased risk of cardiac arrhythmias, cardiomyopathy and sudden coronary death was associated with heavy drinking. There was evidence for a protective effect of alcohol consumption against risk of coronary heart disease, which could be achieved at consumption levels of less than 10 g alcohol a day. The mortality of non-drinkers was higher than that of moderate drinkers in some studies. Level of alcohol consumption and total mortality were dose-related when non-drinkers were excluded. The finding of a dose-relationship between alcohol and harm suggested causality. It was not possible to define individual risk for all harms at a given level of alcohol consumption because of variations in methodology, but some idea of the order of magnitude of the increased risk can be obtained from calculating trends of pooled log-odds ratios. At levels of alcohol consumption of more than 20-30 g a day, all individuals are likely to accumulate risk of harm. Current guidelines on upper limits of lower risk drinking in different countries (168-280 g of alcohol a week for men and 84-140 g a week for women) reflect levels at which the risk of total mortality is not greatly increased above one.

Clinical and histologic features of alcohol drinkers with congestive heart failure

To clarify the difference between alcoholic cardiomyopathy and dilated cardiomyopathy and to investigate the characteristics of alcoholic cardiomyopathy, right ventricular endomyocardial biopsy was performed, and the two diseases were compared clinically and histologically. Changes in the cardiothoracic ratio, cardiac index, and systolic blood pressure/end-systolic volume index were greater after treatment in patients with alcoholic cardiomyopathy than in patients with dilated cardiomyopathy. Histologically, myocytic hypertrophy, fibrosis, and nuclear change were less significant in the former than in the latter. Among patients with alcoholic cardiomyopathy, the cardiac index in those with less fibrosis was greater than in those with more fibrosis. Thus patients with alcoholic cardiomyopathy had more preserved and reversible cardiac function and fewer histologic changes than the patients with dilated cardiomyopathy. Reversibility of cardiac function in patients with alcoholic cardiomyopathy correlated inversely with the severity of histologic changes.

Indirect assessment of acute effects of ethyl alcohol on coronary circulation in patients with chronic stable angina

Acute effects of ethyl alcohol on left ventricular performance, haemodynamic and electrocardiographic response to treadmill exercise test were studied in 20 patients with chronic stable angina. Following ingestion of 80 ml of whisky (43% ethyl alcohol by volume) the mean heart rate and rate-pressure product decreased significantly at the end of each stage of exercise compared to corresponding prealcohol values. There were also significant derangements in systolic time intervals parameters in the form of decrease in left ventricular ejection time I and increase in pre-ejection phase I and pre-ejection phase/left ventricular ejection time ratio after alcohol intake indicating a depression in left ventricular performance. However, following alcohol intake the mean exercise time (6.5 +/- 3.8 minutes) until onset of ischaemic ST segment depression decreased significantly (P less than 0.01) compared to the corresponding prealcohol exercise time (8.6 +/- 3.5 minutes). Interestingly, the mean rate-pressure product (an indicator of myocardial oxygen demand) at the onset of ischaemic ST segment depression was significantly less (P less than 0.01) when exercise test was done after alcohol intake compared to the corresponding pre-alcohol value. The data indicated that despite significant decrease in myocardial oxygen demand produced by alcohol intake, ST T changes developed early and at a lower rate-pressure product, indicating decreased blood flow to the ischaemic zones of the myocardium. This may be explained by the coronary steal effect produced by alcohol.

The acute and chronic effects of ethanol on cardiac muscle protein synthesis in the rat in vivo

An investigation was made into the acute and chronic effects of ethanol on rates of protein synthesis in the hearts of young rats (80-100 g body weight). Acute ethanol administration (75 mmol/kg body weight, IP) significantly reduced the fractional rate of protein synthesis by 20% after 2.5 hr, compared with saline-treated controls. Chronic ethanol feeding (36% of total calories) for 6 weeks significantly reduced cardiac wet weight by 11%, when compared to rats fed isovolumetric amounts of the same diet in which ethanol was substituted by isocaloric glucose. Neither the concentration nor the content of mixed cardiac proteins relative to body weight were overtly altered by chronic ethanol feeding, although, the total content of mixed cardiac proteins were significantly decreased. RNA concentrations and RNA relative to body weight increased slightly, but total cardiac DNA decreased. Indices for the capacity or potential of the heart to synthesis protein (indicated by the RNA/protein and RNA/DNA ratios) and the "DNA-unit" (protein/DNA ratio) were increased in response to chronic ethanol treatment. The fractional and absolute rates of mixed protein synthesis in the heart were (relatively) unaltered by chronic ethanol treatment, as was RNA efficiency and synthesis relative to DNA. It was concluded that the heart displays contrasting responses to acute and chronic ethanol exposure.

Ethanol induced cardiomyopathy--role of periodic fasting

The periodic fasting in presence of continuous ethanol feeding produces pronounced morphological changes in the myocardium and its organelles of the rats. This effect of ethanol could be directly related to the sensitive state of myocardium to the former, specially when ethanol becomes an important source of energy. This is proved further by intraperitoneal injection of 40% ethanol, when profound mitochondrial morphological changes, even leading to formation of lysosome like structures, are evident in the myocardium. The study has stressed the pronounced direct effect of ethanol and its metabolites in the development of morphological changes of the myocardium.

Effects of alcohol on the heart: current views

Chronic and heavy alcohol consumption has deleterious effects upon the cardiovascular system and may cause congestive cardiomyopathy. Evidence of cardiac malfunction has been found in chronic alcoholics without overt heart failure by invasive and noninvasive methods. Ethanol is the incriminated factor having a direct cardiotoxic effect. Electron microscopy and cardiac muscle biopsies show that ethanol may cause changes on plasmalemmal, mitochondrial, and sarcoplasmic membranes. The clinical picture and general management of alcoholic cardiomyopathy do not differ substantially from those of congestive cardiomyopathies of any type. It has, however, been demonstrated that cessation of alcohol consumption may lead to an improved prognosis, even to restoration of normal cardiac function, in individuals with preclinical and mild manifestations of cardiac dysfunction. The literature on the possible association of coronary heart disease with alcohol seems to be ambiguous. It has, however, been postulated recently that moderate alcohol intake may have a protective role against coronary heart disease, in contrast to alcoholic intemperance, which may be a factor favoring coronary heart disease.

An analysis of aboriginal mortality in NSW country regions, 1980-1981

The total number of Aboriginal deaths occurring in selected country regions of New South Wales in 1980 and 1981 has been estimated, based on the deaths reported by Aboriginal health workers and those identified on the newly modified Form of Notification of Death. Aboriginal mortality was more than four times that of the total NSW population, with young and middle-aged adults having death rates up to 12 times higher. The Aboriginal expectation of life at birth was estimated at 48 years for men and 57 years for women. The principal causes of death were diseases of the circulatory system and injuries. The effect of alcohol appeared to be substantial, particularly in the 35-44 year age group.

Ultrastructural features of ethanol-induced cardiomyopathy in turkey poults

Alcoholic cardiomyopathy, characterized by cardiac hypertrophy, was induced in young turkey poults with 5% ethanol. Ultrastructural features included accumulation of glycogen, swollen mitochondria, myofibrillar lysis, increased number of lysosomes, dilated sarcoplasmic reticulum and dense myofibers. Similarity of these alterations to those described in human alcoholic cardiomyopathy confirms the usefulness of the turkey poult as an animal model for this disease syndrome.

Alcohol, lipids and heart disease

The attenuating effect of moderate amounts of alcohol on cardiovascular morbidity and mortality has been reported by several groups of investigators at various geographic locations. At this time, the generally accepted explantation for this cardioprotective effect favors an increase in plasma high-density lipoprotein cholesterol, a factor inversely associated with the development of coronary heart disease (CHD). Other variables potentially influencing the development of CHD such as a reduced tendency for blood coagulation and increased fibrinolytic activity has been enhanced by alcohol and may be considered as possible additional mechanisms for the cardioprotective effects of the agent. Because of its addictive potential, alcohol should not be considered for treatment of CHD.

Alcohol and ischemic heart disease: a review

Evidence from epidemiological studies suggests that consumption of alcohol at moderate levels might be protective against IHD. The alcohol-IHD relationship appears to be U-shaped, so that the risk of IHD associated with moderate levels of alcohol consumption is lower than that for abstainers and heavy drinkers. However, the effects of alcohol upon the risk of IHD must be examined in the context of its overall effects upon health. When this is done, the potential benefits are not clear-cut. This paper reviews the epidemiological evidence relating to the alcohol-IHD association, considers the mechanisms by which alcohol might exert its effects upon IHD risk, and suggests some avenues for future research in this area.

Alcohol and the heart

Acute alcohol ingestion can lead to alterations of either mechanical function or electrophysiologic properties of the heart, whereas chronic consumption can lead to progressive cardiac dysfunction and congestive cardiomyopathy. On the other hand, alcohol appears to have a protective effect for coronary artery disease when consumed in low amounts, although prophylactic use of alcohol is not recommended.

Alcohol consumption and the diet-heart controversy

The effectiveness of dietary changes as a means of reducing blood lipid levels and ultimately controlling the development of coronary heart disease has been debated for many years. The possible effects of alcohol consumption on blood lipids were usually not considered. Our findings indicate a significant positive correlation between the extent of coronary artery occlusion and total plasma cholesterol levels and a negative association between the coronary occlusion and high density lipoprotein (HDL) cholesterol. Since moderate alcohol consumption increases the HDL cholesterol levels, one can also postulate that it affects coronary artery lesions. The attenuating effect of alcohol on the coronary occlusion was negated by sporadic drinking of large amounts of alcohol. In evaluating the possible effect of alcohol on coronary artery disease, it is also necessary to consider its addictive potential as well as other untoward sequelae of alcohol consumption such as hypertension, damage to the myocardium, and increased prevalence of malignancies.

Effect of blackgram fibre on ethanol-induced hyperlipidemia in rats

Rats fed a diet low in fibre and provided with ethanol for 4 weeks showed a higher concentration of cholesterol in the serum, liver and heart, but not in the aorta when compared with control rats not provided with ethanol. Animals maintained on a diet of blackgram fibre (30%) and provided with ethanol had significantly lower concentration of cholesterol in these tissues and in the aorta. The concentration of triglyceride was also raised in the serum, liver and heart in rats fed a diet low in fibre + ethanol. A diet of blackgram fibre caused a significant decrease in serum and liver triglyceride. Fecal excretion of neutral sterols and bile acids decreased in rats fed a diet low in fibre + ethanol, whereas blackgram fibre caused an increase in such fecal excretion.

Cardiovascular status in asymptomatic alcoholics, with reference to the level of ethanol consumption

One hundred and forty-five alcoholics without known causes of heart disease, who were serially admitted to the alcohol detoxification centre, were studied to see the incidence of cardiac abnormalities and dose related effects of ethanol. All patients were divided into heavy (consumed more than the equivalent amount of 125 ml of pure ethanol daily for 10 years or more) and moderate drinkers (consumed 75 to 125 ml of ethanol daily). All of them were ambulatory and free from cardiac symptoms. There was no difference among heavy and moderate drinkers in the incidence of abnormalities detected by the electrocardiograms and chest x-ray films. In the alcoholics, the most frequent finding was a prolonged QTc interval of more than 0.44 s on the electrocardiogram (62 patients, 42.8%), unrelated to serum electrolytes imbalance. Cardiomegaly on chest x-ray film was observed in 25 patients (17.2%). M-mode echocardiogram was recorded in randomly selected patients and compared with age and sex matched controls. The interventricular septum and posterior wall were thicker in alcoholics, while left ventricular volume showed no difference. Left ventricular muscle mass was significantly increased only in heavy drinkers. Left ventricular function at rest was not depressed in these patients at an average of 31 days after the last drink of ethanol. Severe heart failure was not found even among the group of heavy drinkers, of whom more than 90% had liver dysfunction. Cardiac hypertrophy seems to occur in heavy drinkers, but is clinically well compensated in the majority of alcoholics.

Cardiomyopathy with cardiomegaly: a diagnostic dilemma

The clinical angiographic, and available autopsy data of 32 patients with cardiomyopathy with cardiomegaly were reviewed. Twenty-six patients had alcoholic cardiomyopathy. Of these, 20 patients had patient coronary arteries, and 6 had significant occlusive coronary artery disease. Six patients denied any history of excessive alcohol intake, had significant occlusive coronary artery disease, and were grouped as ischemic cardiomyopathic. A total of 12 patients (37.5%) had significant occlusive coronary artery disease. The clinical separation of patients with cardiomegaly due to alcoholic cardiomyopathy from those with occlusive coronary artery disease is extremely difficult. Clinical parameters, including history of chest pain and presence of absence of abnormal Q waves on electrocardiograms, are of little value in individual cases. It seems likely that many patients with ischemic cardiomyopathy may present clinically and electrocardiographically as patients with silent occlusive coronary artery disease. This study underlines the importance of coronary angiography in making a precise diagnosis. The mortality rate during the 5-year follow-up period was 56%. The patients with alcoholic cardiomyopathy with occlusive coronary artery disease carried the worst prognosis. The outlook for patients with cardiomyopathy and cardiomegaly becomes grave once they develop left ventricular end diastolic pressure over 24 mm Hg.

Prevalence of clinically occult cardiomyopathy in chronic alcoholism

The mean absolute heart weight and mean heart weight to body weight ratio of a group of 43 alcoholics, screened from 1,970 consecutive autopsy reports at the Detroit General Hospital by selecting alcoholics with only ethyl alcohol abuse as an etiology of heart disease, are compared to those of a group of similarity selected age-matched nonalcoholic controls. None of the alcoholics was clinically suspected of having had cardiomyopathy. The statistically significant increased mean absolute heart weight and heart weight to body weight ratio of the alcoholic group reflected the presence of subclinical alcoholic cardiomyopathy. In addition, several of the patients in the alcoholic group displayed gross and microscopic cardiac pathologic changes consistent with alcoholic cardiomyopathy occurring in the absence of cardiomegaly.

Ethanol increases rate of isolated atria

Ethanol has a positive chronotropic and negative inotropic effect on isolated spontaneously beating rabbit atria. Both effects increased with increasing ethanol concentrations in the bathing medium. This response is apparently a direct action of ethanol on the myocardium and is not due to the release of catecholamines, acetylcholine, or acetaldehyde produced by the oxidative metabolism of ethanol. Ethanol is one of the few pharmacologic agents having opposite actions on heart rate and force of contraction.

The effect of ethyl alcohol on striated muscle: some clinical and pathological observations

Electrophysiological and pathological studies have been performed on three patients with recurrent focal swelling of the calf muscles simulating deep venous thrombosis, and in a patient with both cardiomyopathy and skeletal muscle disease. In all patients there were elevated CPK levels, histological evidence of an acute myopathy, heavy alcohol intake prior to the development of symptoms, and improvement in hospital with the cessation of alcohol consumption. These patients illustrate a form of alcoholic muscle disease which may be more common than generally realised.

[Norepinephrine levels and morphologic alterations of myocardium in chronic alcoholic rats]

Experimental alcoholism was produced in rats by giving them 32% alcohol as the only source of liquid for 4, 12, and 24 weeks. Control rats were given no alcohol. After 12 and 24 weeks on test the alcohol-fed animals developed pathologic changes and tissue catecholamine alterations of the myocardium. However after 4 weeks there were no differences in myocardial structure and norepinephrine levels between alcohol-fed and control rats. The present experiments indicate that marked increase in norepheinephrine concentration accompanies morphologic evidence of myocardial degeneration and may play a role in the development of the alcoholic cardiomyopathy.

Heart norepinephrine concentration after chronic alcohol ingestion in the rat

The effect of long-term alcohol ingestion on the norepinephrine concentration of the heart was investigated in rats. The alcoholic animals showed a highly significant increase in cardiac norepinephrine concentration as compared with the corresponding controls. It is further suggested that continued exposure to high levels of norepinephrine may play a role in the development of cardiomyopathy in chronic alcoholism.

Effect of ethanol infusion on the ultrastructure of human myocardium

To study the influence of a moderate dose of ethanol on the ultrastructure of myocardium in patients with heart disease, a 7·5% solution of ethanol was infused in six patients with myocardial and valvular disease, who underwent diagnostic cardiac catheterization. Before and after infusion of ethanol an endomyocardial biopsy was performed and the specimens were examined by electron microscopy. After ethanol all six patients revealed alterations in the mitochondrial structure and three of them also showed significant dilatation of the sarcoplasmic reticulum. Cardiac output increased in three of the patients, whereas in two patients a decrease of cardiac output was measured.

The results suggest that the infusion of even small amounts of ethanol is able to provoke structural alterations of myocardial cell organelles and, therefore, possible impairment of myocardial function.