Medtronic, Inc.

Medtronics, Inc.

Lawrence J Mulligan

D Curtis Deno

John E Burnes

Michael R S Hill

David A Igel

Tom Dean Bennett

David E Euler

Edwin G Duffin

Jeffrey M Gillberg

Karen J Kleckner

Douglas A Hettrick

Kenneth C Gardeski

Tommy Dean Bennett

James F Kelley

Vincent E Splett

Orhan Soykan

Kenneth M Anderson

Maura G Donovan

Ruth N Klepfer

Michael B Shelton

Trent M Fischer

Randall L Knoll

Daniel Robert Kaiser

Nirav Vijay Sheth

Glenn C Zillmer

Michael Neidert

Ursula Gebhardt

Robert Cushing Hamlen

Kathleen A Prieve

Ren Zhou

Richard J Shaw

Brian C A Fernandes

Nicholas David Skadsberg

Wael Abo-Auda

Curtis D Deno

A method of stimulation therapy and an apparatus for providing the therapy which addresses cardiac dysfunction including heart failure. The therapy employs atrial pacing pulses delivered to a heart after the atrial refractory period and timed so that they will not cause a ventricular contraction. These atrial pacing are timed to achieve beneficial effects on myocardial mechanics (efficacy) while maintaining an extremely low level of risk of arrhythmia induction. These methods may be employed individually or in combinations in an external or implantable ESS therapy delivery device.

Secure and efficacious therapy delivery for a pacing engine

A method and system for use in selecting a cardiac pacing site includes sensors for tracking wall motion (e.g., sensors coupled to the right and left ventricular heart wall). The wall motion of one or more non-paced cardiac cycles is compared to the wall motion of one or more paced cardiac cycles to determine the effectiveness of one or more pacing sites. For example, image data may be generated to notify the user as to the effectiveness of the one or more pacing sites.

Methods and systems for use in selecting cardiac pacing sites

A method and apparatus for optimizing and assessing the response to extra-systolic stimulation (ESS) are provided. An optimization/monitoring parameter is calculated as a function of potentiation ratio, PR, and recirculation fraction, RF, derived from measurements of myocardial contractile function during and after ESS. PR may be computed as the ratio of the contractile function on post-extra-systolic beats during ESS to baseline contractile function. RF may be computed as the slope of a linear regression performed on a plot of the contractile function for a post-extra-systolic beat versus the contractile function for the previous post-extra-systolic beat after ESS is ceased. The ESI resulting in a maximum optimization/monitoring parameter, preferably computed as the product of PR and RF, is determined as the optimal ESI. The operating ESI may be automatically adjusted, and/or PR and RF data may be stored for monitoring purposes.

Method and apparatus for optimization and assessment of response to extra-systolic stimulation (ESS) therapy

Methods and systems for treating patients with diastolic heart failure (DHF) are disclosed which include slowing a patient's heart rate below its intrinsic rate, and controlling the rate using cardiac pacing therapy to improve LV filling and cardiac output. In certain embodiments, a pacing treatment rate may be determined by adjusting an adaptive rate by an amount determined by evaluating one or more patient parameters.

Method and apparatus for treating diastolic heart failure

A medical device, e.g., an implantable medical device, delivers one or more neurally-excitable stimulation pulses to myocardial tissue during a period when the tissue is refractory. The width of the pulses is less than or equal to approximately one half millisecond. In some embodiments, the current amplitude of the pulses is less than or equal to approximately twenty milliamps. In exemplary embodiments, the medical device delivers a pulse train of six or fewer pulses separated from each other by an interval that is greater than or equal to approximately ten milliseconds. In some embodiments, the medical device delivers pulses according to a schedule stored in a memory, or as a function of a monitored physiological parameter of a patient, such as an intracardiac pressure. In some embodiments, the medical device suspends or withholds delivery of neurally-excitable based on detection of cardiac ischemia.

Cardiac stimulation during a refractory period

In some embodiments, a method of applying stimulation pulse therapy to excitable tissue may include one or more of the following steps: (a) delivering a PESP stimulation therapy to the excitable tissue for a cardiac cycle, (b) delivering a NES stimulation therapy to the excitable tissue during certain cardiac cycles, (c) determining physiologic demand of the patient based on at least one physiologic measurement, (d) determining physiologic demand being placed on a heart based on at least one physiologic measurement, and ceasing the delivery of the NES and PESP stimulation therapy when physiologic demand returns to a base level, and (e) determining physiologic demand being placed on a heart based on at least one physiologic measurement, and modulating the ratio of the number of cardiac cycles in which the NES stimulation therapy is delivered to the number of cardiac cycles in which the PESP stimulation therapy is delivered based on physiologic demand.

System for enhanced cardiac function with combined PESP/NES

Methods and devices for improving ventricular contractile status of a patient suitably exploit changes in ventricular pressure and/or dP/dtto provide and/or optimize a response to a patient. The ventricular pressure may be appropriately correlated to intracellular calcium regulation, which is indicative of contractile status. To assess ventricular contractile status, the device suitably observes a cardiac perturbation of the patient and measures force interval potentiation following the perturbation. The contractile potentiation can then be stored and/or quantified in the implantable medical device to determine the ventricular contractile status of the patient, and an appropriate response may be provided to the patient as a function of the ventricular contractile status. Examples of responses may include administration of drug or neuro therapies, modification of a pacing rate, or the like. Force interval potentiation may also be used to optimize or improve a parameter for a response provided by the implantable medical device.

Method and apparatus for improving ventricular status using the force interval relationship

A hemodynamic status of a patient is determined in an implanted medical device (IMD) by observing a perturbation of the patient's heart, measuring heart rate turbulence resulting from the perturbation, and quantifying the heart rate turbulence to determine the hemodynamic status. The perturbation may be naturally-occurring, or may be generated by the implantable medical device. The patient's response to heart rate turbulence may also be used to provide a response to the patient, such as providing an alarm and/or administering a therapy. Heart rate turbulence may also be used to tune and/or optimize a device parameter such as A-V or V&#x2014;V pacing intervals.

Method and apparatus for gauging cardiac status using post premature heart rate turbulence

Method and apparatus for assessing ventricular contractile status

An implantable heart monitor (IHM) implanted in a patient's body having electrogram (EGM) sense electrodes coupled with EGM sense circuitry to generate sense events upon detection of cardiac depolarizations and a blood pressure measurement transducer disposed in a heart chamber and coupled with blood pressure measurement circuitry operates to assess heart failure state as a function of mechanical pulsus alternans (MPA). MPA episodes are detected, and MPA characteristics of the MPA episode are used alone or as a group as a diagnostic marker of HF state. The MPA episode data set can be stored in memory associated with a time and date stamp. The MPA characteristics of each MPA data set in a series of MPA data sets collected over time can be compared or plotted to determine if a trend indicative of change in HF state is discernible.

Implantable medical device for assessing heart failure state from Mechanical Pulsus Alternans

A system and method for determining mean pulmonary arterial pressure (MPAP) using a pressure sensor located within a ventricle of a heart, and a signal indicative of cardiac electrical activity such as an electrocardiogram (EGM) signal. The pressure may be sensed within the right and/or left ventricle using an implanted pressure sensor. The sensed pressure may be used to determine the Ventricular Systolic Pressure (VSP) and an estimated Pulmonary Arterial Diastolic pressure (ePAD). The VSP, ePAD, and time intervals associated with systole and diastole may then be used to obtain an MPAP that closely approximates mean pulmonary arterial pressure measured using a sensor located in the pulmonary artery.

Method and apparatus for measurement of mean pulmonary artery pressure from a ventricle in an ambulatory monitor

Provided are novel stimulatory device for the controlled production of angiogenic growth factors. More specifically, a subthreshold pulse generator is used for the local production of vascular endothelial growth factor.

Stimulation for delivery of molecular therapy

An implantable stimulator and monitor measures a group of heart failure parameters indicative of the state of heart failure employing EGM signals, measures of blood pressure including absolute pressure P, developed pressure (DP&equals;systolic P&minus;diastolic P), and/or dP/dt, and measures of heart chamber volume (V) over one or more cardiac cycles. These parameters include: (1) relaxation or contraction time constant tau (&tgr;); (2) mechanical restitution (MR), i.e., the mechanical response of a heart chamber to premature stimuli applied to the heart chamber; (3) recirculation fraction (RF), i.e., the rate of decay of PESP effects over a series of heart cycles; and (4) end systolic elastance (E ), i.e., the ratios of end systolic blood pressure P to volume V. These heart failure parameters are determined periodically regardless of patient posture and activity level. The physician can determine whether a particular therapy is appropriate, prescribe the therapy for a period of time while again accumulating the stored patient data for a later review and assessment to determine whether the applied therapy is beneficial or not, thereby enabling periodic changes in therapy, if appropriate. Drug therapies and electrical stimulation therapies, including PESP stimulation, and pacing therapies including single chamber, dual chamber and multi-chamber (bi-atrial and/or bi-ventricular) pacing can be delivered. In patient's prone to malignant tachyarrhythmias, the assessment of heart failure state can be taken into account in setting parameters of detection or classification of tachyarrhythmias and the therapies that are delivered.

Implantable medical device for treating cardiac mechanical dysfunction by electrical stimulation

An implantable stimulator and monitor measures a group of heart failure parameters indicative of the state of heart failure employing EGM signals, measures of blood pressure including absolute pressure P, developed pressure (DP&equals;systolic P&minus;diastolic P), and/or dP/dt, and measures of heart chamber volume (V) over one or more cardiac cycles. These parameters include: (1) relaxation or contraction time constant tau (&tgr;); (2) mechanical restitution (MR), i.e., the mechanical response of a heart chamber to premature stimuli applied to the heart chamber; (3) recirculation fraction (RF), i.e., the rate of decay of PESP effects over a series of heart cycles; and (4) end systolic elastance (E ), i.e., the ratios of end systolic blood pressure P to volume V. These heart failure parameters are determined periodically regardless of patient posture and activity level. However, certain of the parameters are only measured or certain of the data are only stored when the patient heart rate is regular and within a normal sinus range between programmed lower and upper heart rates. The parameter data is associated with a date and time stamp and with other patient data, e.g., patient activity level, and the associated parameter data is stored in IMD memory for retrieval at a later date employing conventional telemetry systems. Incremental changes in the parameter data over time, taking any associated time of day and patient data into account, provide a measure of the degree of change in the heart failure state of the heart.

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Andover, MN, United States of America

Lawrence J Mulligan