Bradyarrhythmia is a condition in which the heart rate (HR) is less than 60 beats per minute, and the heart beats unevenly. The term "flicker" (flutter) is used to describe an arrhythmia where contractions occur regularly but are irregular. In other words, visible contractions can occur quickly—within seconds or minutes—and repeat after a similar period of time. This may be accompanied by fast and weak pulses in other parts of the body. Fibrillation can occur independently or in combination with complex arrhythmias such as bigeminy and trigeminy, although the common term for these combinations is atrial fibrillation (atrial fibrillation). Atrial fibrillation can be dangerous to health and even life. Atrial fibrillation can be caused by lung disease, high blood