Spectrum of heart muscle abnormalities related to alcoholism

Dose dependent but non-linear effects of alcohol on the left and right ventricle

OBJECTIVE

To assess how left (LV) and right ventricular (RV) size, wall thickness, and mass depend on daily alcohol consumption. Among alcoholics, most common findings have been LV hypertrophy and mild systolic or diastolic dysfunction, accompanied occasionally by ventricular dilatation resembling dilated cardiomyopathy. Although it is commonly agreed that chronic heavy alcohol use is injurious to the heart, the dose-injury relation remains a matter of dispute.

DESIGN

Prospective series of 700 Finnish men aged 33-70 years who died out of hospital and underwent a medicolegal necropsy.

METHODS AND RESULTS

Data on alcohol use and other risk factors were obtained from the spouse. At necropsy, a transversal slice of the heart was traced on a transparent sheet and analysed later for LV and RV cavity areas and wall thicknesses. Coronary artery stenoses were measured from silicone casts of the arteries. In analyses of all men, daily alcohol dose predicted heart weight (beta = 0.17, p < 0.001) and RV cavity area (beta = 0.14, p = 0.007) independent of body size, age, coronary artery disease, hypertension, diabetes, and smoking. In the subgroup of men free of significant coronary artery disease, LV area averaged (SEM) 11.0 (1.0) cm(2) in men drinking < 12 g/day, 7.7 (0.7) cm(2) in those drinking 72-180 g/day, and 10.0 (0.9) cm(2) in those drinking > 180 g/day (p = 0.054). Very heavy drinking (> 180 g/day) was associated with an increase in RV cavity area (p = 0.005).

CONCLUSIONS

The effects of alcohol on the heart in middle aged men are dose dependent but partly non-linear. In the absence of coronary artery disease, LV size shows a U shaped reduction with increasing daily alcohol use accompanied by an increase in RV size with very heavy drinking. These findings question the idea of progressive LV dilatation with increasing alcohol consumption among male victims of sudden death.

The effect of the ingestion of ethanol on obstruction of the left ventricular outflow tract in hypertrophic cardiomyopathy

BACKGROUND

Ethanol causes vasodilation, which might have an adverse effect, due to increased obstruction of the left ventricular outflow tract, in patients with hypertrophic obstructive cardiomyopathy. We assessed the hemodynamic effects of the ingestion of ethanol, in an amount commonly consumed socially, in patients with hypertrophic cardiomyopathy.

METHODS

We performed echocardiography in 36 patients before and several times after the ingestion of either 50 ml of 40 percent ethanol or an isocaloric placebo with the aroma of rum. Each patient received both ethanol and placebo, on different days. The patients, but not the physicians, were blinded to the content of the drink. We measured the sizes of the left atrium and left ventricle, the left-ventricular-wall thickness, blood pressure, heart rate, the degree of systolic anterior motion of the mitral valve, and the pressure gradient across the left ventricular outflow tract.

RESULTS

The ingestion of ethanol regulated in a significant drop in the mean (+/- SD) systolic blood pressure (from 130.5 +/- 18.6 to 122.5 +/- 20.3 mm Hg, P<0.001), a significant increase in systolic anterior motion of the mitral valve (from a grade of 2.1 to a grade of 2.5, P<0.001), and a 63 percent increase in the mean gradient across the left ventricular outflow tract (from 38.1 +/- 26.5 to 62.2 +/- 42.4 mm Hg, P<0.001). These changes, which were not associated with symptoms, did not occur after the ingestion of placebo.

CONCLUSION

The ingestion of a small amount of ethanol caused an increase in the gradient across the left ventricular outflow tract in patients with hypertrophic obstructive cardiomyopathy, which could have and adverse clinical effect.

Alcohol and coronary artery disease

Alcohol affects the heart and circulation in several ways. Chronic alcohol consumption can be associated with a variety of cardiovascular disorders, ranging from hypertension and stroke to heart failure and sudden death. At the same time an inverse correlation has been found between moderate drinking and incidence of coronary artery disease, perhaps due to its favourable effects on lipoprotein levels. Reports on acute effects of alcohol on coronary circulation, which may be of great significance in patients with pre-existing heart disease, have been contradictory. However, clinical studies have demonstrated an adverse effect of acute alcohol intake in low to moderate doses on coronary supply-demand relation in patients with angina pectoris. Considering the overall health hazard of alcohol consumption, a recommendation that patients increase their alcohol intake or that they start to drink if they do not already would probably be unjustifiable.

Alcoholic cardiomyopathy

Clinical observations over the past two decades have pointed to the relationship between heart disease and alcohol abuse, usually without evident malnutrition or cirrhosis. While the prevalence of heart failure in the alcoholic population is now known, subclinical abnormalities of left ventricular function in noncardiac alcoholics who were normotensive have a high prevalence with or without some degree of ventricular hypertrophy by echocardiogram. This is frequently a diastolic rather than systolic abnormality. Congestive cardiomyopathy is not infrequently associated with high diastolic arterial blood pressures. Intoxication itself may contribute to blood pressure elevation. Angina pectoris in the absence of significant coronary disease is another presentation. Although the history may not be readily obtained, the major diagnostic feature in this entity is the history of ethanol ingestion in intoxicating amounts for at least 10 years, often marked by periods of spree drinking. While the course of congestive cardiomyopathy may be progressively downhill in individuals who continue to be actively alcoholic after the onset of heart failure, in one series one third of the patients became abstinent. These patients had a 4 year mortality that was persistently one-sixth of the alcoholic group. Management of heart failure is traditional in these patients. Atrial arrhythmias have been shown to occur during the early ethanol withdrawal phase in patients without other clinical evidence of heart disease. Sudden death in a segment of the alcoholic population is considered arrhythmia related and is commonly associated with cigarette use. Identification of the addicted individual is the essential element to management.

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.

Relation of left ventricular function to habitual alcohol consumption

Left ventricular (LV) dysfunction is a frequent finding in chronic alcoholic subjects. LV function's relation to alcohol use in the general population, where low and moderate consumption predominate, was studied in this work. A random sample of 120 people born in 1954 was invited to participate in the study, and 93 (42 men and 51 women) enrolled. Ethanol use was studied by 2-month daily recording of all alcoholic drinks; smoking and physical activity were quantified likewise, and salt intake by 7-day food records. Subsequently, subjects underwent an LV examination by M-mode echocardiography, and a transmitral flow velocity study by pulsed Doppler ultrasound. The relations of LV measurements to alcohol use were studied by multiple linear regression adjusting for sex, body size, blood pressure, heart rate, smoking, physical activity and dietary salt intake. No subject had clinical heart disease. The average daily ethanol consumption ranged from 0 to 1.2 g/kg of body weight (median 0.2). Statistically significant associations with square-root daily ethanol use were found for LV end-systolic diameter (regression coefficient [b] +/- SE 4.0 +/- 1.5 mm/square root of g/kg; p < 0.01), fractional shortening (b = -3.9 +/- 1.8%/square root of g/kg; p < 0.05), peak early transmitral velocity (b = -8.9 +/- 3.5 cm/s/square root of g/kg; p < 0.05), and peak atrial transmitral velocity (b = -4.9 +/- 1.9 cm/s/square root of g/kg; p < 0.05). No interactions with sex were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

The spectrum of left ventricular size in dilated cardiomyopathy: clinical correlates and prognostic implications. SPIC (Italian Multicenter Cardiomyopathy Study) Group

To address the issues of variability and prognostic role of left ventricular dimensions in dilated cardiomyopathy (DCM), 144 patients with DCM were studied. They were arbitrarily assigned to two groups according to an echocardiographic left ventricular end-diastolic diameter index < or = 15% (45 patients with mildly dilated cardiomyopathy) and above 15% (99 patients with typically dilated cardiomyopathy) of the upper normality range. Among the patients with mildly dilated cardiomyopathy, there were more men (89% vs 66%; p < 0.01). This group of patients also had a greater prevalence of atrial fibrillation (22% vs 3%; p < 0.001) higher left ventricular fractional shortening (15 +/- 6% vs 13 +/- 5%; p < 0.05), higher ejection fraction (28 +/- 8% vs 24 +/- 8%; p < 0.01), and a lower exercise tolerance (5 +/- 2 MET vs 6 +/- 2 MET; p < 0.05). At the time of follow-up examination (30 +/- 15 months), event-free survival was not significantly different between patients with mildly dilated cardiomyopathy and those with typically dilated cardiomyopathy. Pulmonary capillary wedge pressure (p < 0.001) and left atrial dimension index (p < 0.01) were significant predictors of prognosis as determined by Cox multivariate analysis. Minimal or mild ventricular dilatation is not uncommon in DCM, and it identifies a heterogenous group of patients--some who are in the early stages of disease and others with severe pump dysfunction and persistently small hearts. Ventricular dilatation is not an independent predictor of prognosis.

Left ventricular size, mass and function in relation to the duration and quantity of heavy drinking in alcoholics

Left ventricular (LV) hypertrophy and mild dysfunction are frequently observed in alcoholics but little is known about how they relate to the duration and severity of alcohol abuse. LV size, mass and function were studied using echocardiography and systolic time intervals in 78 middle-aged male alcoholics who also gave detailed accounts of the duration of heavy drinking, the quantity of recent ethanol consumption and the duration of abstinence. Compared with 34 healthy nonalcoholics, alcoholics had a higher LV mass index (85 +/- 2 [mean +/- standard error] vs 77 +/- 2 g/m2, p = 0.001), a thicker posterior wall (11 +/- 0.2 vs 10 +/- 0.2 mm, p = 0.02), a longer end-systolic diameter index (18 +/- 0.3 vs 17 +/- 0.3 mm/m2, p = 0.02), and a higher preejection period/ejection time ratio (0.36 +/- 0.01 vs 0.33 +/- 0.01, p = 0.002). In multivariate linear regression models, these abnormalities proved independent of the drinking history, except that posterior wall thickness was weakly related to the duration of heavy drinking (standardized correlation coefficient 0.36, p = 0.01). Univariate analyses suggested that the LV mass index and systolic time interval ratio had, if anything, a curvilinear relation to the total duration of heavy alcohol consumption. It is concluded that the LV hypertrophy and dysfunction found in alcoholics are poorly related to the duration and severity of self-reported alcohol abuse. Together with other data, this suggests that there is no simple linear dose-injury relation in the long-term cardiotoxicity of ethanol. Factors modifying the myocardial effects of ethanol need to be studies more in the future.

Acute effects of ethanol on left ventricular diastolic function

Transmitral flow velocities were measured by Doppler echocardiography in nine healthy men who ingested 1 g/kg of ethanol within one hour. The measurements were made before the first drink and every hour thereafter for three hours. The peak mean (SE) blood ethanol concentration was 21.4 (1.0) mmol/l. Each man was also studied after drinking fruit juice. Ethanol increased the heart rate but did not change the peak transmitral velocities, the normalised peak filling rate, the deceleration of early flow, or the duration of relaxation as measured from the second heart sound to the peak early diastolic velocity. The ratio of the peak atrial to the peak early diastolic velocity rose from 0.41 (0.03) to 0.44 (0.03) after ethanol but remained unchanged after juice. The difference between juice and ethanol was independent of changes in heart rate. The fluid balance was more negative in the ethanol experiment (-727 (114) ml v -107 (70) ml), suggesting a reduction in preload, and the ethanol-induced net loss of fluid correlated with the concomitant change in the velocity ratio. A moderate dose of ethanol causes a small acute increase of the ratio of the peak atrial to the peak early diastolic velocity of mitral flow in healthy subjects. Although this change indicates altered diastolic function of the left ventricle, most of it may result from the diuretic effect of ethanol. Any major impairment of ventricular relaxation seems unlikely.

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.