Patent ID: 7016728

Claim:
A pacemaker, designed for emitting stimulation impulses to an atrium of a heart, said pacemaker comprising: a connection for an atrial electrode wire for emitting electrical impulses to the atrium; an atrial stimulation impulse generator, connectable to the atrial electrode wire and designed to generate atrial stimulation impulses that are emitted over the atrial electrode wire; a control unit that is connected to the atrial stimulation impulse generator and designed to trigger the atrial stimulation impulse generator in order to generate and emit atrial stimulation impulses, wherein the control unit is designed in an AF-prevention mode that triggers the stimulation impulse generator to generate a stimulation impulse sequence adapted for preventing atrial fibrillation (AF); and an interval timer, connected to the control unit ( 38 ) and designed to turn the AF-prevention mode on or off according to the time of day and thereby activate or deactivate, in a time-controlled manner, the generation and emission of stimulation impulse sequences preventing atrial fibrillation.