An Australian study published in Heart Rhythm examines whether even moderate alcohol consumption can make preexisting atrial fibrillation more severe.
Atrial fibrillation is one of many cardiovascular disorders that can be fatal if left untreated. In patients with atrial fibrillation, unusual electrical signals in the upper compartments of the heart, called atria, lead to fast and uneven heartbeats. This leads to blood clot formation, which can threaten the lives of people with atrial fibrillation. It has long been known that drinking alcohol has negative effects on people with heart disorders and that alcoholism is, in fact, a risk factor for atrial fibrillation.
Previous studies found that each additional drink raises chance of irregular heartbeats by 8%
The combined results of seven different studies, which included almost 13,000 patients with atrial fibrillation, suggested that every additional drink a day elevates an individual’s chance of atrial fibrillation by 8%. However, the fine line between sound and harmful alcohol amounts remains unclear, as well as what pathological mechanisms are triggered by alcohol in the heart. In a recent study, published in Heart Rhythm, Professor Peter Kistler from the University of Melbourne and his team tackled this complex question.
The study examined how different alcohol quantities injure heart tissue and affect electrical signaling in 75 patients with atrial fibrillation. The patients were divided into three equal groups according to the average number of alcoholic drinks they used to drink in one week over a period of one year. The study defined moderate alcohol consumption as eight to 21 and mild alcohol consumption as two to seven drinks in one week. Participants who drank less than two drinks a week were considered as non-drinkers. An invasive test that characterize atrial anatomy and conductivity was performed in all study participants.
Study highlights the danger of regular alcohol consumption for atrial fibrillation
The study found that moderate alcohol consumption had the most significant effect on their hearts. Scarring and electrical anomalies were observed in patients drinking eight to 21, or 14 on average, drinks a week.
Kistler further explains the findings of this study in a press release: “This study underscores the importance of excessive alcohol consumption as an important risk factor in atrial fibrillation. Regular moderate alcohol consumption, but not mild consumption, is an important modifiable risk factor for atrial fibrillation associated with lower atrial voltage and conduction slowing. These electrical and structural changes may explain the propensity to atrial fibrillation in regular drinkers”.
In other words, moderate alcohol consumption cause physical changes to the hearts of people with atrial fibrillation, which can further lead to potentially life-threatening series of events. These alarming consequences should serve as a red light for the exaggerated alcohol consumption in the Western countries in general, and in patients with heart diseases in particular.
As Professor Peter Kistler explains, “It is an important reminder for clinicians who are caring for patients with atrial fibrillation to ask about alcohol consumption and provide appropriate counselling in those who over-indulge.”
Written by Marina Chemerovski-Glikman, PhD
Reference: Voskoboinik A, Wong G, Lee G, Nalliah C, Hawson J, Prabhu S, Sugumar H, Ling LH, McLellan A, Morton J, Kalman JM, Kistler PM. Moderate alcohol consumption is associated with atrial electrical and structural changes: Insights from high-density left atrial electroanatomic mapping. Heart Rhythm, 2019