Patent ID: 8355781

Claim:
An implantable heart stimulator ( 10 ) comprising: a right-atrial sensing unit ( 62 ), configured to be connected to a right-atrial electrode that is configured to record electrical potentials of myocardium of a right atrium of a heart and is implemented to process electrical signals recorded via the right-atrial electrode and to detect signal features that characterize a right-atrial contraction; a left-ventricular sensing unit ( 66 ), configured to be connected to a left-ventricular electrode that is configured to directly record the electrical potentials of the myocardium of a left ventricle of the heart and indirectly record electrical potentials of the myocardium of the left atrium of the heart is implemented to process electrical signals recorded via the left-ventricular electrode and to detect signal features that characterize a moment of the left-atrial contraction wherein said implantable heart stimulator is not coupled with a left-atrial electrode in the left atrium of the heart.