Abstract: Medical devices and methods are used to treat cardiac dysfunction conditions which involve delivery of stimulation pulses in cardiac refractory periods in order to modulate an effective refractory period (ERP). Such devices and methods may be used in conjunction with or in place of other therapies, including increased cardiac contractility (ICC) therapy, post extrasystolic potentiation (PESP) therapy, and other therapies to achieve increased heart contractility, provide a safer and more effective regimen for the corresponding stimulation therapies, and reduce the risk of inducing an arrhythmia.

Abstract: A method of controlling pulmonary capillary pressure is disclosed which includes increasing the output of a first ventricle (V1) (e.g., a left ventricle) relative to second ventricle (e.g., right ventricle) by increasing the magnitude of a post extrasystolic potentiation (PESP) therapy effect in the first ventricle relative to the magnitude of a PESP therapy effect produced in the second ventricle. In certain embodiments of the invention, this may be accomplished by adjusting the extra-stimulus interval (ESI) in either or both of the left ventricle and the right ventricle, for example.

Abstract: An implantable cardiac stimulation device capable of delivering ESS, monitoring for myocardial ischemia and responding to the detection of myocardial ischemia by modifying the delivery of ESS. Modification of ESS delivery may include disabling ESS, initiating ESS, and/or modifying ESS control parameters.

Abstract: According to the present invention, discrete measurements of fluid pressure development (and derivatives thereof) are used in optimizing hemodynamics for cardiac resynchronization therapy (CRT) delivery and multiple chamber cardiac pacing, and in enhancing hemodynamics in the event of a sub-optimal left-side lead placement. For example, such diverse pressure measurements include: maximum positive or negative dP/dt values, ePAD, RV systolic, RV diastolic, pulse pressure, and the like. According to the present invention, on a periodic basis or upon demand one or more cardiac pacing intervals are iteratively cycled through a predetermined range and the resulting pressure measurements stored for comparison. The cardiac pacing intervals are then adjusted based at least in part upon the most appropriate, or desirable, measured hemodynamics of the patient. The present invention may be implemented as computer readable instructions executed by a microprocessor-based implantable medical device.