Definition
Fibrillation is a rapid, irregular, and unsynchronized contraction of muscle fibers. It's often associated with the heart, where it disrupts normal blood flow. Imagine your heart quivering instead of pumping steadily; that's fibrillation. It's not a coordinated movement but a chaotic one. Fibrillation can occur in other muscles, too, like in the eyelids. This uncoordinated contraction can be dangerous if left untreated. It can lead to serious health issues.