An implantable system for detecting electrical signals of a human heart or an animal heart, the implantable system comprising: a processor, a memory unit, a first detection unit for detecting an atrial activity, a second detection unit for detecting a right ventricular activity, and a third detection unit for detecting a left ventricular activity, said memory unit including a computer-readable program prompting said processor to automatically carry out steps at regular intervals upon said program being executed on said processor, said steps including: a1) detecting an intrinsic right atrial activity by using said first detection unit; b1) detecting an intrinsic right ventricular activity by using said second detection unit; and c1) determining a time having passed between the intrinsic right atrial activity and the intrinsic right ventricular activity, and storing said time as an atrioventricular conduction time; and/or a2) detecting an intrinsic right ventricular activity by using said second detection unit; b2) detecting an intrinsic left ventricular activity (109, 110, 111, 112) by using said third detection unit; and c2) determining a time having passed between the intrinsic right ventricular activity and the intrinsic left ventricular activity, and storing said time as an interventricular conduction time (113, 114, 115, 116); said program being configured to prompt said processor to carry out said steps once within a time period of from 3 hours to 48 hours and characterized in that said program being configured to prompt said processor to carry out said steps during a determination and/or an adaptation of a detection threshold of the implantable system. a processor, a memory unit, a first detection unit for detecting an atrial activity, a second detection unit for detecting a right ventricular activity, and a third detection unit for detecting a left ventricular activity, said memory unit including a computer-readable program prompting said processor to automatically carry out steps at regular intervals upon said program being executed on said processor, said steps including: a1) detecting an intrinsic right atrial activity by using said first detection unit; b1) detecting an intrinsic right ventricular activity by using said second detection unit; and c1) determining a time having passed between the intrinsic right atrial activity and the intrinsic right ventricular activity, and storing said time as an atrioventricular conduction time; and/or a2) detecting an intrinsic right ventricular activity by using said second detection unit; b2) detecting an intrinsic left ventricular activity (109, 110, 111, 112) by using said third detection unit; and c2) determining a time having passed between the intrinsic right ventricular activity and the intrinsic left ventricular activity, and storing said time as an interventricular conduction time (113, 114, 115, 116); a1) detecting an intrinsic right atrial activity by using said first detection unit; b1) detecting an intrinsic right ventricular activity by using said second detection unit; and c1) determining a time having passed between the intrinsic right atrial activity and the intrinsic right ventricular activity, and storing said time as an atrioventricular conduction time; and/or a2) detecting an intrinsic right ventricular activity by using said second detection unit; b2) detecting an intrinsic left ventricular activity (109, 110, 111, 112) by using said third detection unit; and c2) determining a time having passed between the intrinsic right ventricular activity and the intrinsic left ventricular activity, and storing said time as an interventricular conduction time (113, 114, 115, 116); said program being configured to prompt said processor to carry out said steps once within a time period of from 3 hours to 48 hours and characterized in that said program being configured to prompt said processor to carry out said steps during a determination and/or an adaptation of a detection threshold of the implantable system.