Abstract: According to a method and device for modulating intracellular calcium concentration in biological tissue, a stimulation probe is applied to the tissue, a non-excitatory stimulation pulse is generated, and the pulse is conveyed to the stimulation probe. In one embodiment concerning cardiac tissue, a stimulation probe is applied to a patient's heart, a signal is received from at least one sensor responsive to the patient's cardiac muscle activity, a non-excitatory stimulation pulse responsive to the signal is generated, and the pulse is conveyed to the stimulation probe.

Abstract: Apparatus (170) for heart pacing with hemodynamic improvement, including one or more electrodes (36), which convey electrical signals to respective cardiac muscle segments. Signal generation circuitry (50) applies an extended pacing signal (60, 61), having an overall duration greater than three times a chronaxie time, to the one or more electrodes so as to pace the heart. The signal preferably includes a train of a plurality of biphasic pulses, and has an amplitude at least three times as great as a threshold for pacing the heart, but not sufficient for cardioversion.

Abstract: A method of modifying the force of contraction of at least a portion of a heart chamber is provided. A non-excitatory electric field of given duration is applied, at a delay after an activation of the heart, which increase the force of contraction by at least 5%. Apparatus is also provided for pacing with hemodynamic improvement. Circuitry applies an extended pacing signal to electrodes to pace the heart, the extended pacing signal having an overall duration greater than 8 ms from a time of initiation of application of that portion of the signal that initiates action potential propagation. The signal includes a train of biphasic pulses having pulse durations of at least 1 ms, and the signal has an amplitude that is at least three times as great as a threshold for pacing the heart and that is sufficient neither for cardioversion nor for defibrillation. Other embodiments are also described.

Abstract: According to a method and device for modulating intracellular calcium concentration in biological tissue, a stimulation probe is applied to the tissue, a non-excitatory stimulation pulse is generated, and the pulse is conveyed to the stimulation probe. In one embodiment concerning cardiac tissue, a stimulation probe is applied to a patient's heart, a signal is received from at least one sensor responsive to the patient's cardiac muscle activity, a non-excitatory stimulation pulse responsive to the signal is generated, and the pulse is conveyed to the stimulation probe.

Abstract: According to a method and device for modulating intracellular calcium concentration in biological tissue, a stimulation probe is applied to the tissue, a non-excitatory stimulation pulse is generated, and the pulse is conveyed to the stimulation probe. In one embodiment concerning cardiac tissue, a stimulation probe is applied to a patient's heart, a signal is received from at least one sensor responsive to the patient's cardiac muscle activity, a non-excitatory stimulation pulse responsive to the signal is generated, and the pulse is conveyed to the stimulation probe.