defibrillator: devices that apply an electric charge or current to the heart to restore a normal heartbeat. If the heart rhythm stops due to cardiac arrest, also known as sudden cardiac arrest (SCA), a defibrillator may help it start beating again
fibrillate /ˈfɪbrɪleɪt/ v. (of a muscle, especially in the heart) make a quivering movement due to uncoordinated contraction of the individual fibrils.
"the atria ceased to fibrillate when the temperature was reduced"
fibril /ˈfaɪbrɪl/ n. plural noun: fibrils 原纤维 a small or slender fibre.
"each muscle fibre is subdivided into smaller fibrils"
