German researchers studied the correlation between cardiac arrhythmia and alcohol consumption by monitoring 3,000 middle-aged volunteers for 16 days during Oktoberfest. Portable electrocardiographs and breathalyzer machines tested for heart activity and breath alcohol concentration. Arrhythmia showed up in 30 percent of the participants, significantly higher than an estimated 4 percent or less among the general population according to an earlier study. An irregular heartbeat often causes discomfort in the short term and possible heart failure and stroke later.