“Welcome to Medical Jeopardy!” “Thank you, Johnny. Dr T. Totaler is our defending champion. Please start us off and pick a category”. “Thanks Alex. I’ll take Alcohol and Atrial Fibrillation for $200”. “Here is the answer: None. Yes, Dr T, what is the question?” “How much alcohol is safe to drink with a history of atrial fibrillation?”
Atrial fibrillation (Afib) is a very common heart rhythm disturbance. Afib is a rapid, irregular rhythm in the upper chambers of the heart (the atria). Instead of a regular, coordinated beat in the atria, the rhythm is rapid and disorganized. Afib is a major health problem associated with stroke, congestive heart failure and death. Alcohol has a long, complicated and conflicting history with heart disease. On one hand, light to moderate alcohol consumption (7 or less drinks per week for women, 14 or less drinks per week for men) lowers the risk of heart attack and heart deaths. This protective effect does not extend to the heart’s electrical system as alcohol has been associated with Afib for years. Alcohol impacts the heart in two circumstances, during binge drinking and after years of habitual consumption.
Afib occurring after binge drinking has been termed “Holiday Heart Syndrome,” due the tendency to consume extra alcohol on a weekend or a holiday. Holiday Heart Syndrome may occur in regular drinkers as well as nondrinkers. Afib may occur at the time of intoxication, or within 36 hours after the binge. Afib may be caused by an excess release of adrenaline during the hangover phase, resulting in a higher heart rate and causing irritability of the heart’s electrical system. In addition, alcohol’s diuretic effect can lead to low levels of potassium and magnesium in the blood, which can also trigger Afib. Afib in Holiday Heart Syndrome is felt to be benign as it usually lasts only 24 hours, but patients are prone to repeated episodes of Afib, especially with repeated binges.
In addition to binge drinking, years of light to moderate alcohol use may be a risk factor for Afib. A study that followed 79,000 patients who did not have Afib found that even moderate alcohol consumption (1-3 drinks per day) increased the risk for Afib. For each extra alcoholic drink consumed per day, the risk of Afib increased by 8%. The more alcohol consumed, the greater the risk for Afib. A recent review could not find a level of daily alcohol use that was safe for patients with Afib. Alcohol use over many years may cause Afib by increasing the size of the atria and by causing scarring in the atria due to inflammation. In addition, long standing alcohol use may lead to hypertension (high blood pressure) and sleep apnea. All of these factors, atrial enlargement, atrial scarring, hypertension and sleep apnea predispose the heart to Afib.
Many studies have shown that light to moderate alcohol consumption decreases the risk for heart artery disease, heart attacks and heart deaths. However, these studies were done in healthy adults, not in those with heart disease or a history of Afib. In addition, these studies recently have been called into question and the benefits of alcohol may be overstated.
So, a small amount of alcohol may be protective for the hearts of healthy adults who do not have a history of heart problems or a prior history of Afib. For those with heart disease and especially those with previous episodes of Afib, it appears that no amount of alcohol is safe. The protective effect of small amounts of alcohol in preventing a heart attack needs to be balanced against the risk for developing AFib.