Alcohol As A Hazard Of Heard Diseases

After smoking, excess alcohol is the second most common cause of preventable death. Alcohol is toxic to virtually every organ in the human body, but when consumed in moderate amounts, it is detoxified by the liver and does little or no harm. Alcoholic beverages contain ethyl alcohol (ethanol), which is metabolized in the body to acetaldehyde. In large amounts, both ethanol and acetaldehyde interfere with normal functions of organs throughout the body, including the heart.

There is a significantly higher incidence of high blood pressure among those who consume more than 2 ounces of ethanol a day (which translates into 4 ounces of 100-proof whiskey, 16 ounces of wine, or 48 ounces of beer). Abrupt withdrawal of alcohol from those consuming large amounts on a regular basis may cause the condition known as delirium tremens (DTs), which is associated with a significant risk of cardiac arrest.

Binge drinking can provoke arrhythmias (irregular heart rhythms)-frequently in the form of atrial fibrillation-in people with no previous symptoms of heart disease. This alcohol-induced rhythm disturbance is most common among people who have chronically abused alcohol. It is sometimes called “holiday heart” because it often occurs over the holidays or on weekends, after consumption of more alcohol than usual. People who are deprived of sleep are susceptible to developing “holiday heart” from drinking too much at one time, even if they do not regularly abuse alcohol.

Alcohol is thought to provoke arrhythmias by stimulating the sympathetic nervous system. Alcoholics tend to have higher blood levels of the chemical messengers of this system such as epinephrine (adrenaline). Deficiency of the trace mineral magnesium, which often occurs with chronic alcohol abuse, may also play a role.

Up to a third of all cases of a type of heart disease called cardiomyopathy are attributed to excessive drinking. Alcoholic cardiomyopathy occurs most often in middle-aged men. In this disorder, the heart muscle (myocardium)—particularly the right and left ventricles—enlarges and becomes flabby. As the working cells deteriorate, they become more sparse, and are replaced by fibers of connective tissue in the spaces between the cells (interstitial fibrosis). Eventually, alcoholic cardiomyopathy can result in heart failure, in which the heart does not pump blood efficiently to all parts of the body. Fatigue, shortness of breath during exercise, and swelling in the ankles are its most common symptoms. The heart’s inability to send blood efficiently to the kidneys, where excess salt and water are normally filtered out, means the body begins to retain salt, and thus water. This in turn raises blood volume and causes a backup of fluid into tissues such as the lungs (hence the breathing difficulty).

When individuals with congestive heart failure caused by alcoholic consumption continue to drink, their prognosis is poor. In contrast, those who abstain from alcohol raise their chances of reversing the progress of alcoholic cardiomyopathy, especially if the problem is detected early Their hearts may return to normal size, and they can live for many years. In fact, patients with alcoholic cardiomyopathy who abstain from drinking have a better prognosis than do patients with cardiomyopathy from other causes.

Physicians once believed that malnutrition was the sole mechanism by which alcohol damaged the heart. In extreme cases, alcoholics consume too many calories as drink and not enough as food, and they become malnourished. This could cause depletion of the protein in heart muscle. However, it is now recognized that in most cases, alcohol damages the heart even in the absence of malnutrition.