Patent ID: 8712526

Claim:
Apparatus for seeking an optimal configuration of stimulation through an active medical device ( 10 ) by resynchronization pacing of at least two ventricular pacing sites, comprising: Means for delivering pacing pulses ( 10 , 30 ) to be applied to electrodes located respectively in at least one right ventricular pacing site and at least one left ventricular pacing site in a predetermined and modifiable current pacing configuration; An acceleration sensor having an output endocardial acceleration (EA) signal representative of the cyclic contractions and relaxations of a patient's heart; and Means for isolating and preprocessing in the EA signal during one cardiac cycle between two successive ventricular events: (i) an EA1 component corresponding to the first peak of endocardial acceleration associated with the isovolumetric ventricular contraction, and (ii) an EA2 component corresponding to the second peak of endocardial acceleration associated with the isovolumetric ventricular relaxation, means ( 40 ) for evaluating an effectiveness of said current pacing configuration, including: Means for extracting at least two characteristic parameters from the isolated and pre-processed EA1 and EA2 components: Means for combining said at least two characteristic parameters in a composite index representative of the effectiveness of that current pacing configuration; Means for determining a plurality of values of said composite index for a corresponding plurality of different pacing configurations; and Means for determining a preferred pacing configuration from said plurality of values of said composite index, based on finding an optimum composite index, Wherein: Said at least two characteristic parameters of the EA1 and EA2 components are parameters selected from among the group consisting of: PEA1=value of the EA1 peak-to-peak component; TstEA1=timing of occurrence of the beginning of the EA1 component, represented by a time interval between i) a time marker of the beginning of the cardiac cycle and ii) the crossing of a threshold of energy envelope of the EA1 component; LargEA1=time interval between i) said crossing of the energy envelope threshold of the EA1 component and ii) the instant of the peak of said energy envelope of the EA1 component; and Syst=duration of systole, represented by the time interval between the beginning (TstEA1) of the EA1 component and the beginning (TstEA2) of the EA2 component, Wherein said composite index is an index selected from among the group consisting of: Ind 1 =(TstEA1×LargEA1)/(Syst×PEA1); Ind 2 =(TstEA1×LargEA1)/[(Syst−LargEA1)×PEA1]; Ind 3 =(TstEA1×LargEA1)/(Syst) and Ind 4 =(TstEA1)/(PEA1), and Wherein said optimum composite index comprises a minimum of said selected index.