Heavy drinking, especially bingeing, makes platelets more likely to clump together into blood clots, which can lead to heart attack or stroke. In a landmark study published in 2005, Harvard researchers found that binge drinking doubled the risk of death among people who initially survived a heart attack.
Heavy drinking can also cause cardiomyopathy, a potentially deadly condition in which the heart muscle weakens and eventually fails, and is commonly associated with the heart-rhythm abnormalities atrial and ventricular fibrillation. Moderate to high alcohol intake is associated with an increased incidence of atrial fibrillation among people aged 55 or older with cardiovascular disease or diabetes.
Atrial fibrillation, in which the heart’s upper chambers (atria) twitch chaotically rather than constrict rhythmically, can cause blood clots that can trigger a stroke. Ventricular fibrillation causes chaotic twitching in the heart’s main pumping chambers (ventricles). It causes rapid loss of consciousness and, in the absence of immediate treatment, sudden death.