St. Jude Medical Ab

Siemens Elema Ab

Pacestetter Ab

Roland Heinze

Karl Stangl

Kurt Hoegnelid

Kenth-Ake-Sune Nilsson

Nils Holmstroem

Pierre Westin

Karin Ljungstroem

Michael Laule

A cardiac pacemaker has a pulse generator which emits stimulation pulses which are respectively separated by stimulation intervals and which collectively have an average duration. A modulation device alternatingly shortens and lengthens the stimulation intervals, without changing the average duration. An evaluation unit analyzes signals detected after each stimulation pulse and determines the electric restitution of the heart at the average stimulation interval duration on the basis of a measurement of the duration of the action potential. Changes in a measuring variable, associated with the duration of the action potential, caused by the modulation of the stimulation intervals is determined in a relationship to the average duration of the stimulation interval. This relationship is compared with at least one predetermined value, and the average duration of the stimulation interval is controlled on the basis of this comparison.

Cardiac pacemaker with adjustable stimulation interval

In a method and apparatus for operating an implantable cardiac pacemaker, the stimulation rate is modulated, while a patient in whom the pacemaker is implanted is experiencing a number of different levels of physical stress, and a number of signal sequences corresponding to a non-mechanical physiological characteristic are obtained, one sequence being obtained for each physical stress level. These signal sequences form a reference field, which is stored in the pacemaker. A current signal sequence of the non-mechanical physiological characteristic is subsequently obtained, and this signal sequence is compared to all of the signal sequences in the stored reference field, and one of the reference field signal sequences having the highest correlation with the current signal sequence is selected. The stimulation rate is then set at a rate equal to the basic stimulation rate for the modulation which produced the highest correlating sequence in the reference field.

Cardiac pacemaker and pacing method using detection of physical stress

A pressure and heart movement sensor for a heart stimulator, includes an electrode system for implantation with an electrode cable containing at least two electrical conductors leading to electrode poles. A measurement device is arranged to measure an electrical quantity between the electrical conductors, which quantity varying according to the pressure applied to the electrode cable. Alternately, the electrode cable contains at least one electrical conductor, and the measurement device is arranged to measure the impedance between the conductor and ambient medium and to deliver an output signal, which varies according to the impedance measured, when the electrode cable is subjected to pressure.

Pressure and heart movement sensor for heart stimulators

Growing community of inventors

Berlin, Germany

Roland Heinze