Importance of abstention from alcohol in alcoholic heart disease

Toxic Mechanisms of the Heart: A Review*

Toxic injury is one of the many ways by which the functional integrity of the heart may become compromised. Any of the subcellular elements may be the target of toxic injury, including all of the various membranes and organelles. Understanding the mechanisms underlying cardiotoxicity may lead to treatment of the toxicity or to its prevention. Doxorubicin and its analogs are very important cancer chemotherapeutic agents that can cause cardiotoxicity. Other agents which are cardiotoxic and which have profound public health implications include the alkaloid emetine in ipecac syrup, cocaine, and ethyl alcohol. The most important cardiotoxic mechanisms proposed for doxorubicin include oxidative stress with its resultant damage to myocardial elements, changes in calcium homeostasis, decreased ability to produce ATP, and systemic release of cardiotoxic humoral mediators from tissue mast cells. Each of the first 3 mechanisms can lead to each of the other 2, and the causal relationships between all of these mechanisms are not clear. New evidence suggests that doxorubicinol, one of the metabolites of doxorubicin may be the moiety responsible for cardiotoxicity. Several other potential mechanisms also have been proposed for doxorubicin. Emetine in ipecac syrup is the first aid treatment of choice for many acute toxic oral ingestions and the alkaloid, itself, is used to treat amebiasis. Cardiotoxicity occurs following chronic exposure, such as occurs therapeutically in amebiasis and with ipecac abuse by bulemics. A number of mechanisms are proposed for emetine cardiotoxicity, but the current mechanistic literature is quite scarce. Cocaine abuse recently has caught the public interest, in particular because of the drug-related sudden deaths of certain athletes. Cocaine can cause hypertension, arrhythmias, and reduced coronary blood flow, each of which can contribute to its lethality. However, it may be possible that cocaine sudden death episodes are more related to hyperthermia and convulsive seizures, rather than to cardiovascular toxicity. Chronic alcohol use leads to dilated cardiomyopathy and failure as part of the general physical degeneration that occurs with alcoholism. Several mechanisms are proposed for the cardiomyopathy, but only 2 things seem clear. The cardiotoxicity is due to an intrinsic effect of alcohol, rather than to malnutrition or co-toxicity, and abstinence is the only effective treatment for the cardiomyopathy. Recent articles indicate that very moderate use of alcohol may be beneficial and protect against cardiovascular-related morbidity. One explanation for these findings seems to be that the non-drinking groups, against whom the moderate drinking comparisons were made, were enriched in former drinkers with significant alcohol-related cardiovascular pathology.

Alcoholic cardiomyopathy

Alcohol is the most frequently consumed toxic substance in the world. Low to moderate daily intake of alcohol has been shown to have beneficial effects on the cardiovascular system. In contrast, exposure to high levels of alcohol for a long period could lead to progressive cardiac dysfunction and heart failure. Cardiac dysfunction associated with chronic and excessive alcohol intake is a specific cardiac disease known as alcoholic cardiomyopathy (ACM). In spite of its clinical importance, data on ACM and how alcohol damages the heart are limited. In this review, we evaluate available evidence linking excessive alcohol consumption with heart failure and dilated cardiomyopathy. Additionally, we discuss the clinical presentation, prognosis and treatment of ACM.

Outpatient management of chronic heart failure

Critical to the success of managing heart failure is appropriate outpatient follow up. Various models of care integrate medical care, pharmacologic intervention, and patient education and support. Key factors in any program are frequent patient assessment with rapid response to even subtle changes in the patient's condition. As the disease progresses, alternative care options such as palliative care and hospice should be integrated into the patient's care regimen.

Medical management of mild-to-moderate heart failure before the advent of beta blockers

Clinical trials of beta blockers in heart failure have generally required that patients be receiving optimal drug therapy before randomization to the study medication. Therefore, because beta blockers are used in addition to conventional drug therapy, review of the standard drug therapy of mild-to-moderate heart failure before the advent of beta blockade is essential to understanding the role of beta blockers in the treatment of heart failure. The conventional medical management of systolic heart failure includes angiotensin-converting enzyme (ACE) inhibitors, which should be used as first-line therapy; diuretics, for the management of body fluid-volume excess; digoxin; and some other vasodilators. These therapies have been evaluated in large-scale, randomized, controlled trials. ACE inhibitors have been shown to significantly attenuate disease progression and improve outcome (ie, morbidity and mortality) in patients with mild-to-moderate systolic heart failure. Controversial or unproven therapies include nonglycoside inotropic agents, angiotensin II receptor antagonists, antiarrhythmic agents, anticoagulants, and calcium channel blockers. The pharmacologic management of diastolic heart failure is largely empirical and is directed at reducing symptoms. Symptoms caused by increased ventricular filling pressures may be treated with diuretics and long-acting nitrates. Some calcium channel blockers and most beta blockers prolong diastolic filling time by slowing heart rate, thereby potentially improving the symptoms of diastolic heart failure. Calcium antagonists, beta blockers, diuretics, and ACE inhibitors may also promote regression of left ventricular hypertrophy and thus improve ventricular compliance, possibly preventing the development of diastolic dysfunction. Because randomized controlled trials of diastolic heart failure are lacking, this review focuses on the conventional management of mild-to-moderate systolic heart failure before the advent of beta blockade.

Nonpharmacologic treatment of heart failure in the elderly

Nonpharmacologic therapy is an integral part of the management of elderly patients with heart failure. Reinforcement of dietary sodium restriction and other nutritional concerns are critical features of therapy. Quality standards for the management of patients with heart failure are being developed, and the implementation of these standards is a goal of clinicians. A multidisciplinary approach to elderly patients with heart failure is beneficial.

Prevention of relapse in patients with congestive heart failure: the role of precipitating factors

Relapse of congestive heart failure (CHF) frequently occurs and has serious consequences in terms of morbidity, mortality, and health care expenditure. Many studies have investigated the aetiological and prognostic factors of CHF, but there are only limited data on the role of precipitating factors that trigger relapse of CHF. Knowledge of potential precipitating factors may help to optimise treatment and provide guidance for patients with CHF. The literature was reviewed to identify factors that may influence haemodynamic homeostasis in CHF. Precipitating factors that may offer opportunities for preventing relapse of CHF were selected. Potential precipitating factors are discussed in relation to the pathophysiology of CHF: alcohol, smoking, psychological stress, uncontrolled hypertension, cardiac arrhythmias, myocardial ischaemia, poor treatment compliance, and inappropriate medical treatment. Poor treatment compliance in particular is frequently encountered in patients with CHF. Furthermore, studies of medical treatment under everyday circumstances indicate that some aspects of the management of CHF can be improved. In conclusion, the identification of precipitating factors for relapse of CHF may strongly contribute to optimal treatment. Improvement of treatment compliance and optimalisation of medical treatment may offer important possibilities to clinicians to reduce the number of relapses in patients with CHF.

Cardiovascular effects of alcohol

The ingestion of one or two alcoholic drinks can affect heart rate, blood pressure, cardiac output, myocardial contractility, and regional blood flow. These actions generally are not clinically important. In the presence of cardiovascular disease, however, even such small quantities of alcohol might result in transient unfavorable hemodynamic changes. Moreover, alcohol abuse can produce cardiac arrhythmias, hypertension, cardiomyopathy, stroke, and even sudden death. In contrast, moderate alcohol use produces changes that have an overall favorable effect on atherosclerotic-related vascular diseases. Because cardiovascular disease due to atherosclerosis is the leading cause of death in Western society, this desirable effect of alcohol use outweighs its detrimental actions, resulting in favorable findings in population studies. Nevertheless, the body of evidence argues against encouraging alcohol use for its cardiovascular effects.

The integration of medical management with recovery

Patients recovering from alcohol and other drug addiction have unique medical and pharmacological needs. Careful selection of medications call decrease the risk of relapse. Angiotensin-converting enzyme inhibitors and calcium channel-blocking medications are excellent choices to treat hypertension. Most gastrointestinal problems resolve with abstinence and can be treated nonpharmacologically. In managing pain, physicians should avoid narcotics and use nonpharmacological treatment whenever possible. Treating recovering patients with HIV can be challenging because of the side effects of many of the antiviral medications. The newer antiviral agents have fewer side effects and contraindications. Commonly used remedies for colds and cough can cause a relapse to drug use. Patients with diabetes mellitus need to be monitored very closely in early recovery to prevent hypoglycemia. Frequently a team approach is helpful in managing the medication needs of patients in recovery.

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.