of pacing configuration the device collects and analyzes an endocardial acceleration signal and searches for an optimal pacing configuration based upon a performance index derived from at least one value relating to one and or the other of the two endocardial acceleration peaks over a given heart cycle optimization search operates through a scanning of a parameter e g atrio ventricular delay and calculation of the surface area underneath the characteristic of the peak amplitude as a function of the scanned parameter application_number US 42566806 A description one will now describe a preferred embodiment of the present invention preliminarily regarding the software related aspects thereof the invention can be implemented by means of an appropriate programming of the software of a known active implantable device for example of a triple or quadruple chamber pacemaker type device comprising a ventricular resynchronization mode the invention can notably be applied to the implantable devices marketed by ela medical montrouge france such as the symphony and rhapsody brand pacemakers these devices are equipped with programmable microprocessors including circuits intended to acquire format and process electrical signals collected by implanted electrodes and deliver pacing pulses to these electrodes it is also possible to upload towards these devices by telemetry software routines that will be stored in internal memory and run so as to implement the features of the invention described in more details below implementing the features of the invention into these devices is easily feasible by a person of ordinary skill in the art and will therefore not be described in detail herein the curve at the top of fig1 represents the variations of endocardial acceleration ea measured by a sensor such as that described.