An active implantable medical device for the treatment of heartbeat rate disorders including the detection, analysis and treatment of ventricular pauses. The device includes circuits for delivering ventricular stimulation, circuits for detecting a normal spontaneous ventricular cardiac activity; a circuit for controlling ventricular stimulation that is suitable to control the application of a stimulation in the absence of normal spontaneous ventricular activity; and the continuous recording of the current cardiac information, such as detected cardiac activity and/or of parameters representative of those events. It also includes an algorithm for the controlled inhibition of the ventricular stimulation such that ventricular pauses of a duration greater than a predetermined value (X) are detected, wherein the predetermined value evolves over time in a progressive manner, and the ventricular pauses occur during the periods of controlled inhibition of the ventricular stimulation. The last recorded current cardiac events and/or event markers preceding a detection of the ventricular pause are preserved. Also, stimulation at a physiological back-up frequency is provided in the event of a detected ventricular pause.