Abstract: Provided herein are implantable systems that include an implantable photoplethysmography (PPG) sensor, which can be used to obtain an arterial PPG waveform. In an embodiment, a metric of a terminal portion of an arterial PPG waveform is determined, and a metric of an initial portion of the arterial PPG waveform is determined, and a surrogate of mean arterial pressure is determined based on the metric of the terminal portion and the metric of the initial portion. In another embodiment, a surrogate of diastolic pressure is determined based on a metric of a terminal portion of an arterial PPG waveform. In a further embodiment, a surrogate of cardiac afterload is determined based on a metric of a terminal portion of an arterial PPG waveform.

Abstract: An embodiment relates to a method for delivering a vagal stimulation therapy to a vagus nerve, including delivering a neural stimulation signal to non-selectively stimulate both afferent axons and efferent axons in the vagus nerve according to a predetermined schedule for the vagal stimulation therapy, and selecting a value for at least one parameter for the predetermined schedule for the vagal stimulation therapy to control the neural stimulation therapy to avoid physiological habituation to the vagal stimulation therapy. The parameter(s) include at least one parameter selected from the group of parameters consisting of a predetermined therapy duration parameter for a predetermined therapy period, and a predetermined intermittent neural stimulation parameter associated with on/off timing for the intermittent neural stimulation parameter.

Abstract: The disclosure describes techniques for associating therapy adjustments with posture states using stability timers. The techniques may include detecting a patient adjustment to electrical stimulation therapy delivered to the patient, sensing a posture state of the patient, and associating the detected adjustment with the sensed posture state if the sensed posture state is sensed within a first period following the detection of the adjustment and if the sensed posture state does not change during a second period following the sensing of the sensed posture state.

Abstract: A method of identifying a potential cause of pulmonary edema is provided. The method includes obtaining one or more impedance vectors between predetermined combinations of the electrodes positioned proximate the heart. At least one of the impedance vectors is representative of a thoracic fluid level. The method also includes applying a stimulation pulse to the heart and sensing cardiac signals of the heart that are representative of an electrophysiological response to the stimulation pulse. The method further includes monitoring the cardiac signals and at least one of the impedance vectors with respect to time to identify the potential cause of pulmonary edema.

Abstract: A medical system comprises a plurality of electrodes; at least one sensor configured to output at least one signal based on at least one physiological parameter of a patient; and a processor. The processor is configured to control delivery of stimulation to the patient using a plurality of electrode configurations. Each of the electrode configurations comprises at least one of the plurality of electrodes. For each of the electrode configurations, the processor is configured to determine a first response of target tissue to the stimulation based on the signals, and a second response of non-target tissue to the stimulation based on the signals. The processor is also configured to select at least one of the electrode configurations for delivery of stimulation to the patient based on the first and second responses for the electrode configurations. As examples, the target tissue may be a left ventricle or vagus nerve.

Abstract: Methods for monitoring a patient's level of B-type natriuretic peptide (BNP), and implantable cardiac systems capable of performing such methods, are provided. A ventricle is paced for a period of time to provoke a ventricular evoked response, and a ventricular intracardiac electrogram (IEGM) indicative of the ventricular evoked response is obtained. Based on the ventricular IEGM, there is a determination of at least one ventricular evoked response metric (e.g., ventricular evoked response peak-to-peak amplitude, ventricular evoked response area and/or ventricular evoked response maximum slope), and the patient's level of BNP is monitored based on determined ventricular evoked response metric(s). Based on the monitored level's of BNP, the patients heart failure (HF) condition and/or risks and/or occurrences of certain events (e.g., an acute HF exacerbation and/or an acute myocardial infarction) can be monitored.

Abstract: Exemplary methods and apparatuses are disclosed that provide for determination of an atrio-ventricular delay on a beat-to-beat basis by determining a P-wave duration from electric signals corresponding to electric potentials in a heart, and determining the atrio-ventricular delay on a beat-to-beat basis such that the atrio-ventricular delay for an individual heart cycle depends on the P-wave duration of a same or an immediately preceding heart cycle.

Abstract: The present disclosure is directed to the detection of coughs and coughing episodes using acoustic signals. In various examples, an implantable medical device processes an acoustic signal obtained from an acoustic sensor to determine whether a patient has coughed. In some examples, the implantable medical device also performs a cough severity assessment. In some examples, the cough severity assessment may include a determination of the depth of the cough, the duration of the coughing episode, or whether the cough was wet or dry.

Abstract: In a method and implantable medical device for ventricular tachyarrhythmia detection and classification, upon detection of a ventricular tachyarrhythmia based on an electrocardiogram signal, cardiogenic impedance data representative of ventricular volume dynamics are collected and used for classifying the detected tachyarrhythmia as stable or unstable. In the latter case but typically not in the former case, defibrillation shocks or other forms of therapy are applied to combat the unstable ventricular tachyarrhythmia.

Abstract: Implantable systems, and methods for use therewith, enable the monitoring of a patient's electromechanical delay (EMD) and arterial blood pressure. Paced cardiac events are caused by delivering sufficient pacing stimulation to cause capture. A cardiogenic impedance (CI) signal, indicative of cardiac contractile activity in response to the pacing stimulation being delivered, is obtained. One or more predetermined features of the CI signal are detected, and a value indicative of the patient's EMD is determined by determining a time between a delivered pacing stimulation and at least one of the detected one or more features of the CI signal. The value indicative of EMD can be used to more accurately determine metrics indicative of pulse arrival time (PAT), which can be used to estimate arterial blood pressure.

Abstract: A method and system of detecting phrenic nerve stimulation in a patient that includes detecting an activation event, obtaining a heart sound signal of a patient from an implanted heart sound sensor, determining that an electrical stimulation has been applied to the patient, in response to detecting the activation event, monitoring a portion of the heart sound signal, the portion defined by a predetermined window after the application of the electrical stimulation, and determining whether phrenic nerve stimulation occurred based on the portion of the heart sound signal.

Abstract: In various method embodiments, a supraventricular arrhythmia event is detected, and a supraventricular arrhythmia treatment, including neural stimulation to elicit a sympathetic response, is delivered in response to a detected supraventricular arrhythmia event. Some embodiments detect a precursor for a supraventricular arrhythmia episode, and deliver prophylactic neural stimulation to avoid the supraventricular arrhythmia event. Some embodiments detect a supraventricular arrhythmia episode, and deliver therapeutic neural stimulation for the supraventricular arrhythmia event.

Abstract: Adaptive rate pacing for improving heart rate kinetics in heart failure patients involves determining onset and sustaining of patient activity. The patient's heart rate response to the sustained activity is evaluated during a time window defined between onset of the activity and a steady-state exercise level. If the patient's heart rate response to the sustained activity is determined to be slow, a pacing therapy is delivered at a rate greater than the patient's intrinsic heart rate based on a profile of the patient's heart rate response to varying workloads. If determined not to be slow, the pacing therapy is withheld. Monitoring-only configurations provide for acquisition and organization of physiological data for heart failure patients. These data can be acquired on a per-patient basis and used to assess the HF status of the patient.

Abstract: A cardiac rhythm management device for obtaining transthoracic impedance. The device comprises a sensor for obtaining a signal indicative of an action of a heart, an impedance measurement circuit adapted to measure transthoracic impedance and a processor for utilizing the signal indicative of the action of the heart to sample the transthoracic impedance at sampling intervals commenced by fiducial markers in the signal indicative of the action of the heart, where the sampling of the impedance signal removes the component of a stroke volume of the heart from the signal and thereby provides lung ventilation information.

Abstract: Systems, devices and methods for defining, identifying and utilizing composite parameter indices from health-related parameters are disclosed. One aspect is a programmable device having machine executable instructions for performing a method to assist with managing a patient's health. In various embodiments, a first set of at least two health-related parameters is acquired. A first composite parameter is generated using the first set of at least two health-related parameters. Other aspects and embodiments are provided herein.

Abstract: A computer-based method for reducing or eliminating baseline drift from a biological (bio) signal includes the steps of dividing the bio signal into a plurality of shorter signals having fixed time intervals, fitting a corresponding portion of a baseline function to a baseline of a respective one of each of the shorter signals, and subtracting the baseline function from the bio signal, resulting in a bio signal with a flat baseline.

Abstract: Exemplary techniques and systems for interpolating left ventricular pressures are described. One technique interpolates pressures within the left ventricle from blood pressures gathered without directly sensing blood pressure in the left ventricle.

Abstract: Improving cardiac response in terms of pressure, ejected volume, and filling and ejection times by cardiac reverse remodelling, including temporary, occasionally harmful stimulation sequences. An original pacing configuration (a) is switched to a modified pacing configuration (b) in a direction opposite to that of an optimization of the hemodynamic parameters, to cause an immediate change in the response to controlled stimulation of the myocardium. This response is assessed based on: the maximum value (P (b, a)) achieved by the peak-to-peak (PEA (i)) of the first peak of endocardial acceleration (PEA) after a pacing configuration change, the mean PEA value (A (b, a)) after stabilization, the PEA variability (V (b, a)) around this average value, and the duration (T (b, a)) of stabilization after the pacing configuration change.

Abstract: The present invention generally relates to implantable stimulation devices, such as pacemakers, defibrillators, and cardioverters, and, in particular, to implantable medical devices using atrial based pacing such as an AAI pacing mode and methods for such implantable medical devices for detecting early stages of incipient A-V node malfunction as well as presence of A-V node malfunction. An AV conduction capacity is detected, wherein a sensed ventricular event following an intrinsic or paced atrial event during a predetermined period of time indicates good AV conduction capacity and wherein absence of a ventricular event within the predetermined period of time indicates poor AV conduction capacity. At least one A-V node function parameter indicating a function of the A-V node is determined, wherein the A-V node function parameter includes whether a status of the AV conduction capacity is good or poor.

Abstract: The disclosure includes methods and systems for treating ventricular arrhythmias. Embodiments include an implantable cardiac device or system including a determining module that determines a value of a parameter indicative of a rate of an intrinsic pacemaker of a heart of a patient experiencing fast ventricular arrhythmia (FVA) and a delivery module, programmed to deliver therapy for ventricular arrhythmias to a patient. Some methods include determining a value of a parameter indicative of a rate of an intrinsic pacemaker of a heart of a patient experiencing an FVA; if the value indicates the rate is about equal to or higher than a threshold, delivering a first therapy to the patient for terminating the FVA, and if the value indicates the rate is lower than the threshold, delivering a second therapy, different from the first therapy, to the patient for terminating the FVA.

Abstract: Methods, apparatus, and systems are provided to stimulate multiple sites in a heart. A controller senses electrical activity associated with sinus rhythm of the heart. A signal generator is configured to generate an electrical signal for stimulating the heart. Based on the electrical signal, a distributor circuit then distributes the stimulating signals, such as pacing pulses, to a heart. The distributor circuit may vary the delay time between stimulating signals, inhibit a stimulating signal, trigger application of a stimulating signal, or vary the characteristics, such as the pulse width and amplitude, of a stimulating signal.

Abstract: An implantable device and method for monitoring S1 heart sounds with a remotely located accelerometer. The device includes a transducer that converts heart sounds into an electrical signal. A control circuit is coupled to the transducer. The control circuit is configured to receive the electrical signal, identify an S1 heart sound, and to convert the S1 heart sound into electrical information. The control circuit also generates morphological data from the electrical information. The morphological data relates to a hemodynamic metric, such as left ventricular contractility. A housing may enclose the control circuit. The housing defines a volume coextensive with an outer surface of the housing. The transducer is in or on the volume defined by the housing.

Abstract: Techniques are provided for detecting heart failure or other medical conditions within a patient using an implantable medical device, such as pacemaker or implantable cardioverter/defibrillator, or external system. In one example, physiological signals, such as immittance-based signals, are sensed within the patient along a plurality of different vectors, and the amount of independent informational content among the physiological signals of the different vectors is determined. Heart failure is then detected by the implantable device based on a significant increase in the amount of independent informational content among the physiological signals. In response, therapy may be controlled, diagnostic information stored, and/or warning signals generated. In other examples, at least some of these functions are performed by an external system.

Abstract: A maternal-fetal monitoring system for use during all stages of pregnancy, including antepartum and intrapartum stages. The maternal-fetal monitoring system of the subject invention comprises (1) a set of sensors; (2) an amplifying/filtering means; (3) a computing means; and (4) a graphical user interface. Accurate clinical data, which can be extracted and provided to the user in real-time using the system of the invention, include without limitation, maternal electrocardiogram (ECG) signals, maternal uterine activity signals (EHG), maternal heart rate, fetal ECG signals, and fetal heart rate. In a preferred embodiment, the maternal-fetal monitoring system of the invention includes an intelligence means, such as a neural network system, to analyze and interpret clinical data for use in clinical diagnosis antepartum, intrapartum and postpartum, as well as delivery strategy.

Abstract: A method of determining pacing therapy for an individual patient including determining representative electromechanical physiologic characteristics for a plurality of normal patients having a range of anatomical dimensions and developing a plurality of normal templates. Each template indicates the representative electromechanical physiologic characteristics of a group of normal patients having similar anatomical dimensions.

Abstract: An implantable medical device has an impedance or admittance determination unit, an alternating current or voltage source, a measuring unit, and an analysis unit which is connected to the alternating current or AC voltage source and the measuring unit to calculate an impedance value or an admittance value at different times. The impedance or admittance determination unit may generate measuring current having two different frequencies (preferably below 100 kHz), and the analysis unit may calculate pairs of impedance or admittance values which are chronologically assigned to one another for different frequencies of the measuring current, and calculate a value for a blood impedance or blood admittance component which is independent of the impedance of the body tissue surrounding a particular blood vessel, The analysis unit may also determine trends in this value over time as an indicator for a change of blood hematocrit value.

Abstract: Systolic timing intervals are measured in response to delivering pacing energy to a pacing site of a patient's heart. An estimate of a patient's acute response to cardiac resynchronization therapy (CRT) for the pacing site is determined using the measured systolic timing intervals. The estimate is compared to a threshold. The threshold preferably distinguishes between acute responsiveness and non-responsiveness to CRT for a patient population. An indication of acute responsiveness to CRT for the pacing site may be produced in response to the comparison.

Abstract: An implantable medical device, IMD, comprises atrial and ventricular sensing units for sensing atrial or ventricular electric events. The IMD also comprises atrial and ventricular pulse generators for generating atrial or ventricular pacing pulses. A controller controls the operation of the IMD (100) according to a first mode, in which the ventricular pulse generator is prevented from generating a back-up pulse if an evoked response detector fails to detect evoked response to a delivered ventricular pacing pulse, and a second mode, in which the ventricular pulse generator is controlled to generate a back-up pulse if no evoked response is detected following delivery of a ventricular stimulating pulse. The controller switches operation from the first mode to the second mode based on the evoked response detector failing to detect an evoked response to a delivered ventricular pacing pulse.

Abstract: Systems and methods involve determination of CRT parameters using a number of CRT optimization processes. Each CRT optimization process attempts to return recommended parameters. The CRT parameters are determined based on the recommended parameters returned by one or more of the CRT optimization processes. The CRT optimization processes may be sequentially implemented and the CRT parameters may be determined based on the recommended parameters returned by a first CRT optimization process to return recommended parameters. The CRT parameters may be determined based on a combination of the recommended parameters returned. The CRT optimization processes implemented may be selected from available CRT optimization processes based on patient conditions.

Abstract: Safety pacing in multi-site cardiac rhythm management (CRM) devices is provided. According to various method embodiments, a first cardiac signal from a first cardiac region and a second cardiac signal from a second cardiac region are sensed. The first cardiac region is paced to maintain at least a minimum cardiac rate, and the second cardiac region is paced to maintain at least the minimum cardiac rate when a pace in the first cardiac region is inhibited. Other aspects and embodiments are provided herein.

Abstract: In an implantable medical device, such as a cardiac stimulator such as a pacemaker, and method for predicting patient responses to physical exertion, the patient response is monitored over time to evaluate disease progression and pacing therapies of cardiac stimulators are adapted based on the predicted patient response. A current cardiac status indicator for the patient is created indicating a response of the patient to an increased physical activity as a primarily heart rate response or as a primarily a stroke volume response. The pacing parameters of the cardiac stimulator can thereafter be adapted depending on the current cardiac status indicator, wherein the adapted pacing parameters include a first pacing setting if the current cardiac status indicator indicates a primarily heart rate response or a second pacing setting if the current cardiac status indicator indicates a primarily stroke volume response.

Abstract: Treatment of heart failure in a patient by electrically modulating both the sympathetic and parasympathetic autonomic cardiac nerve fibers that innervate the patient's heart at an extravascular site in the pericardial space of the heart. The extravascular site is any suitable single location inside the chest cavity that carries both sympathetic and parasympathetic cardiac nerves such as the cardiac plexus or the pericardial transverse sinus or any two separate extravascular sites with one site carrying predominantly sympathetic cardiac nerves and the other site carrying predominantly parasympathetic cardiac nerves for electrically modulating the balance of autonomic cardiac nerve control.

Abstract: Techniques are provided for use with implantable medical devices for addressing encapsulation effects, particularly in the detection of cardiac decompensation events such as heart failure (HF) or cardiogenic pulmonary edema (PE.) In one example, during an acute interval following device implant, cardiac decompensation is detected using heart rate variability (HRV), ventricular evoked response (ER) or various other non-impedance-based parameters that are insensitive to component encapsulation effects. During the subsequent chronic interval, decompensation is detected using intracardiac or transthoracic impedance signals. In another example, the degree of maturation of encapsulation of implanted components is assessed using impedance frequency-response measurements or based on the frequency bandwidth of heart sounds or other physiological signals.

Abstract: An implantable cardiac pacing device delivering minimum ventricular pacing and an associated method control intervals timed by the device during sensing and pacing. An atrial-only pacing mode is set in response to sensing intrinsic ventricular events in the ventricular chamber. A first post-ventricular atrial refractory period is set following each of a plurality of ventricular events sensed in the ventricular chamber, and atrial events each being sensed during first post-ventricular atrial refractory periods are detected. A second post-ventricular atrial refractory period is set in response to detecting the atrial events each being sensed during the first post-ventricular atrial refractory period.

Abstract: An exemplary method includes emitting radiation subcutaneously; sensing at least some of the emitted radiation as reflected cutaneously; detecting an abnormal physiologic condition; and, based at least in part on the sensing, adjusting a stimulation therapy to treat the detected abnormal condition. In such a method, the abnormal condition may be an abnormal cardiac condition, an abnormal neural condition or other condition. Various other methods, devices, systems, etc., are also disclosed.

Abstract: Method and apparatus for preventing heart rhythm disturbances by recording cardiac electrical activity, measuring beat-to-beat variability in the morphology of electrocardiographic waveforms, and using the measured beat-to-beat variability to control the delivery of electrical impulses to the heart during the absolute refractory period.

Abstract: Selection of an appropriate rate programming control (RPC) setting in an implantable medical device (IMD), uses analysis of VA coupling surrogate conditions. The VA coupling surrogate conditions are derived from signals such as cardiogenic impedance, blood pressure, and the pulsatile components of PPG. By analyzing a waveform of the measured surrogate condition, the IMD estimates wall stiffness, through the slope of the waveform, and peripheral arterial pressure, through the reflection time between the main wave and reflection wave of the waveform. These values are plotted against each other on a VA coupling coordinate plane. Based on the location and orientation of the resulting VA coupling plot, the IMD selects an appropriate RPC setting.

Abstract: A system and method are provided for determining an index of autonomic nervous system (ANS) or sympathetic nervous system (SNS) activity for use in patient monitoring or therapy delivery control. An ANS or SNS index is calculated as a function of multiple monitored physiological variables that strongly correlate to changes in autonomic or sympathetic tone. These ANS-influenced variables are derived from selected hemodynamic and/or electrical signals and may include variables relating to any of: the maximum rate of pressure rise (dP/dtmax), the maximum rate of pressure decline (dP/dtmin), pulse pressure (PP), pre-ejection time interval (PEI) and/or systolic time interval (STI), heart rate (HR), heart rate variability (HRV), and baro-reflex gain. Changes in the ANS or SNS index may be used to automatically adjust a device delivered therapy.

Abstract: A blood flow rate sensor has at least one transmitter for emitting waves into a blood vessel, the propagation of which is deflected by cellular blood components, and at least two receiver units for receiving waves emitted by the transmitter. The receiver units are spaced from each other in the direction of blood flow, and are situated such that each receives waves from a different path through the blood. The output signal of each receiver unit is filtered or otherwise processed to obtain a noise component, and the noise components from the receiver units are cross-correlated to determine a time offset between the output signals. The time offset is inversely proportional to the blood flow rate.

Abstract: A system and method for managing preload reserve and tracking the inotropic state of a patient's heart. The S1 heart sound is measured as a proxy for direct measurement of stroke volume. The S3 heart sound may be measured as a proxy for direct measurement of preload level. The S1-S3 pair yield a point on a Frank Starling type of curve, and reveal information regarding the patient's ventricular operating point and inotropic state. As an alternative, or in addition to, measurement of the S3 heart sound, the S4 heart sound may be measured or a direct pressure measurement may be made for the sake of determining the patient's preload level. The aforementioned measurements may be made by a cardiac rhythm management device, such as a pacemaker or implantable defibrillator.

Abstract: A cardiac rhythm management (CRM) system includes an implantable medical device that senses a wireless electrocardiogram (ECG), which is a signal sensed with implantable electrodes and approximating a surface ECG. In one embodiment, the wireless ECG is sensed as a substitute signal for the intracardiac electrogram when the sensing of the intracardiac electrogram becomes unreliable.

Abstract: The presence of a cardiac pulse in a patient is determined by evaluating physiological signals in the patient. In one embodiment, a medical device evaluates two or more different physiological signals, such as phonocardiogram (PCG) signals, electrocardiogram (ECG) signals, patient impedance signals, piezoelectric signals, and accelerometer signals for features indicative of the presence of a cardiac pulse. Using these features, the medical device determines whether a cardiac pulse is present in the patient. The medical device may also be configured to report whether the patient is in a VF, VT, asystole, or PEA condition, in addition to being in a pulseless condition, and prompt different therapies, such as chest compressions, rescue breathing, defibrillation, and PEA-specific electrotherapy, depending on the analysis of the physiological signals. Auto-capture of a cardiac pulse using pacing stimuli is further provided.

Abstract: Systems and methods using a heart valve and an implantable medical device, such as for event detection and optimization of cardiac output. The cardiac management system includes a heart valve, having a physiological sensor. The physiological sensor is adapted to measure at least one of an intrinsic electrical cardiac parameter, a hemodynamic parameter or the like. The system further includes an implantable electronics unit, such as a cardiac rhythm management unit, coupled to the physiological sensor of the heart valve to receive physiological information. The electronics unit is adapted to use the received physiological information to control delivery of an electrical output to the subject.

Abstract: In an embodiment, the invention includes an implantable medical device with a pulse generator and a chemical sensor in communication with the pulse generator, the chemical sensor configured to detect an ion concentration in a bodily fluid. In an embodiment, the invention includes a method for providing cardiac arrhythmia therapy to a patient including sensing a physiological concentration of an analyte, communicating data regarding the physiological concentration of the analyte to an implanted pulse generator, and delivering therapy to the patient based in part on the physiological concentration of the ion. In an embodiment, the invention includes a method for monitoring diuretic therapy. In an embodiment, the invention includes a method for controlling delivery of an active agent into a human body. Other aspects and embodiments are provided herein.

Abstract: The disclosure relates to a method and system for obtaining baseline patient information. In some examples, a method may include acquiring first patient data, wherein the first patient data comprises at least one of first posture state data indicative of a plurality of posture states of a patient during a first time period or first therapy adjustment data indicative of a plurality of patient therapy adjustments made during the first time period; generating baseline patient information based at least in part on the first patient data; and comparing the baseline patient information to patient information generated based on second patient data. Therapy is not delivered to the patient according to a detected posture state of the patient during the first time period, and therapy is delivered to the patient according to the detected posture state of the patient during the second time period.

Abstract: The disclosure herein relates generally to methods for treating heart conditions using vagal stimulation, and further to systems and devices for performing such treatment. Such methods may include monitoring physiological parameters of a patient, detecting cardiac conditions, and delivering vagal stimulation (e.g., electrical stimulation to the vagus nerve or neurons having parasympathetic function) to the patient to treat the detected cardiac conditions.

Abstract: The disclosure herein relates generally to methods for treating heart conditions using vagal stimulation, and further to systems and devices for performing such treatment. Such methods may include monitoring physiological parameters of a patient, detecting cardiac conditions, and delivering vagal stimulation (e.g., electrical stimulation to the vagus nerve or neurons having parasympathetic function) to the patient to treat the detected cardiac conditions.

Abstract: An assembly includes an implantable medical device (IMD) including a conductive housing, and a fixation element assembly attached to the IMD. The fixation element assembly includes a set of active fixation tines and an insulator to electrically isolate the set of active fixation tines from the conductive housing of the implantable medical device. The active fixation tines in the set are deployable from a spring-loaded position in which distal ends of the active fixation tines point away from the implantable medical device to a hooked position in which the active fixation tines bend back towards the implantable medical device. The active fixation tines are configured to secure the implantable medical device to a patient tissue when deployed while the distal ends of the active fixation tines are positioned adjacent to the patient tissue.

Abstract: Apparatus for diastole trimming including a controller for producing a diastole ending signal, and one or more leads connected to the controller, for carrying the signal to lead connections to a heart, characterized by the controller detecting when a left ventricle (LV) of the heart is mostly full, and producing the diastole ending signal such that the diastole duration is trimmed. Apparatus for diastole trimming including a controller for producing a diastole ending signal, and a connection to a pacemaker, characterized by the controller having decision rules for indicating to the pacemaker when to fire and end the diastole. A method of programming a pacemaker characterized by increasing cardiac output by trimming duration of diastole. A method for increasing cardiac output including producing a signal to trim diastole duration, thereby increasing heart rate (HR) and increasing a product of stroke volume (SV) times HR. Related apparatus and methods are also described.

Abstract: An active implantable medical device with atrial pacing for the treatment of diastolic heart failure. This device comprises circuits and leads for collecting right and left atrial events (16,18) and pacing the left atrium (18) and a sensor detecting myocardium contractions, preferably an endocardial acceleration sensor (20), delivering a signal representative of the myocardium contractions. Analysis of the signal allows a determination of the presence or absence of a detectable left atrial contraction distinguishable from the ventricular contraction. An interatrial delay is applied between the collection of a right atrial depolarization and the delivery of a left atrial pacing pulse. In the absence of left atrial contraction, the interatrial delay is iteratively reduced in successive cardiac cycles from an initial value to an adjustment value ensuring that a left atrial contraction appears, and then so maintained while the presence of a left atrial contraction continues.