Patent ID: 7433738

Claim:
A device for stimulating a muscle contraction of a muscular-driven heart assist system which operates in parallel or in series with a diseased heart, comprising: a pulse generator unit for generating and supplying electric stimulation pulses to a muscle of the muscular-driven heart assist system; a control unit for controlling the pulse generator unit for setting an amplitude and a frequency of the stimulation pulses and for causing the stimulation pulses to be applied to the muscle of the muscular-driven heart assist system to be stimulated; a detection unit for detecting an instantaneous, spontaneous or stimulated heart rhythm of a wearer of the device; a housing receiving the pulse generator unit, the control unit and the detection unit; a memory module for storing a temporal course of the number of supplied stimulation pulses within a defined time interval; a counting unit and a memory unit for counting and storing a number of stimulation pulses supplied during the defined time interval, wherein the stimulation pulses are grouped into variable stimulation bursts; a determination unit for determining an arithmetically averaged (mean) stimulation frequency within the defined time interval, with the mean stimulation frequency being computed as the quotient of the number of stimulation pulses of the variable stimulation bursts supplied during the defined time interval and stored in the memory unit and the defined time interval in which the stimulation pulses are counted and stored; a continuously operating evaluation unit for ascertaining that the mean stimulation frequency stays within preset limit values, wherein the limit values of the mean stimulation frequency can be preset in a range between 0.2 stimulation pulses per second and a maximum of 2 stimulation pulses per second; pulse conservation means for reducing the mean stimulation frequency depending on the limit values preset in the evaluation unit, wherein the pulse conservation means comprise a computing unit configured to compute a stimulation pattern according to an equation which determines the stimulation pattern as a function of the mean stimulation frequency and varies the number of stimulation pulses during a stimulation burst to generate and maintain type-IIa muscle fibers and to revent their conversion to type-I muscle fibers; and a monitoring unit worn by the wearer of the device external to the body for displaying the mean stimulation frequency and for self-control of the patient.