Abstract: A medical device system and associated method classify candidate pacing electrode sites for delivering pacing pulses to a patient's heart. A control unit is operatively coupled with a plurality of electrodes for controlling the delivery of the pacing pulses, and a sensing module senses a cardiac signal generated in response to the delivered pacing pulses. A processor is configured to deliver a first pacing pulse at a first timing interval to a first pacing site, determine the cardiac signal sensed in response to the delivered first pacing pulse and determine a first morphology corresponding to the determined sensed cardiac signal, compare the first morphology to a threshold morphology and adjust the first timing interval to a second timing interval different from the first timing interval in response to the comparing, and determine the optimal pacing site in response to the adjusting.

Abstract: Methods and apparatus of left ventricular pacing including automated adjustment of a atrio-ventricular (AV) pacing delay interval and intrinsic AV nodal conduction testing. Thus, in the event that the AV conduction test reveals a physiologically acceptable intrinsic PR interval then storing the physiologically acceptable PR interval in a memory structure (e.g., a median P-R from one or more cardiac cycles) and delivering fusion pacing using a decremented value of the intrinsic PR interval.

Abstract: An implantable medical device receives both heart sound and electrogram signals. A processor within the implantable medical device extracts physiologically relevant information from both the heart sound signal and the electrogram signal. Based on the extracted physiologically relevant information a set of pacing parameters is evaluated. In certain examples, the values of the pacing parameters may be changed by the implantable medical device in response to the physiologically relevant information extracted from the heart sound signal and the electrogram signal.

Abstract: Delivery of fusion pacing therapy to a later depolarizing ventricle (V2) of a heart of a patient may be timed based on the depolarization of the V2 during at least one prior cardiac cycle. In some examples, a V2 pacing pulse is delivered upon the expiration of a pacing interval that begins at detection of an atrial sense or pace event (AP/S). The pacing interval may be substantially equal to the duration of time between an AP/S and a V2 sensing event of at least one prior cardiac cycle decremented by an adjusted pre-excitation interval (PEI). In another example, the V2 pacing pulse is delivered at the expiration of a pacing interval that begins upon detection of a V2 sensing event of a prior cardiac cycle. The pacing interval may be substantially equal to a duration of time at least two subsequent V2 sensing events decremented by the adjusted PEI.

Abstract: A medical device and method for determining a parameter for delivery of a predetermined pacing therapy that includes a plurality of electrodes to deliver a pacing therapy, including the predetermined pacing therapy, and a control unit to control the timing of the delivery of the pacing therapy, including the predetermined pacing therapy, by the electrodes. A processor generates a first template in response to the pacing therapy being delivered to only one of a right ventricle and a left ventricle, and a second template in response to the pacing therapy being delivered to only the other of the right ventricle and the left ventricle, and determines the parameter in response to a comparing of subsequently delivered pacing therapy to the first template and the second template.

Abstract: A medical device system and method for delivering mechanically fused left ventricular cardiac stimulation. A sensor monitors left ventricular acceleration while left ventricular cardiac stimulation is provided at an AV interval. The left ventricular acceleration is used to calculate a mechanical response interval and the mechanical response interval is compared to a desired mechanical response interval. The AV interval is adjusted until the mechanical response interval is equal to the desired mechanical response interval.

Abstract: Provided herewith are methods and apparatus for optimizing an atrioventricular (AV) pacing delay interval based upon ECG-based optimization is calculated as a linear function of P-wave duration, sensed PR (intrinsic) interval, sensed or paced QRS duration and heart rate. Since the relationship among these parameters is linear, once the coefficients are solved (which can be any value, including null) with reference to a known optimized AV interval (AVopt) such as from an echocardiographic study, an AVopt value can be dynamically adjusted in an ambulatory subject. The various combinations of values can be loaded into a look up table or calculated automatically. And, since some of the parameters do not typically change much over time they can be determined acutely and fed into the equation while the other values can be measured frequently. The parameter values can be measured by an implantable medical device such as a dual- or triple-chamber pacemaker.

Abstract: Methods and apparatus for optimizing an atrioventricular (AV) pacing delay interval based upon ECG-based optimization is calculated as a linear function of P-wave duration, sensed PR (intrinsic) interval, sensed or paced QRS duration and heart rate. Since the relationship among these parameters is linear, once the coefficients are solved (which can be any value, including null) with reference to a known optimized AV interval (AVopt) such as from an echocardiographic study, an AVopt value can be dynamically adjusted in an ambulatory subject. The various combinations of values can be loaded into a look up table or calculated automatically. And, since some of the parameters do not typically change much over time they can be determined acutely and fed into the equation while the other values can be measured frequently. The parameter values can be measured by an implantable medical device such as a dual- or triple-chamber pacemaker.

Abstract: A medical device system and method for delivering mechanically fused left ventricular cardiac stimulation. A sensor monitors left ventricular acceleration while left ventricular cardiac stimulation is provided at an AV interval. The left ventricular acceleration is used to calculate a mechanical response interval and the mechanical response interval is compared to a desired mechanical response interval. The AV interval is adjusted until the mechanical response interval is equal to the desired mechanical response interval.

Abstract: Provided herewith are methods and apparatus for optimizing ventricle-to-ventricle (V-V) pacing delay intervals based upon ECG-based optimization calculated as a linear function of P-wave duration sensed PR (intrinsic) interval sensed (or paced) QRS duration and heart rate. Since the relationship among these parameters is linear, once the coefficients are solved (which can be any value, including null) with reference to a known optimized V-V interval such as from an echocardiographic study, an operating V-V interval value can be dynamically adjusted in an ambulatory subject. The various combinations of values can be loaded into a look up table or calculated automatically. And, since some of the parameters do not typically change much over time they can be determined acutely and fed into the equation while the other values can be measured more frequently. The parameter values can be measured by an implantable medical device such as a dual- or triple-chamber pacemaker.

Abstract: Techniques are described for detecting conduction abnormalities in a heart of a patient. In particular, an IMD may be configured to obtain electrical signals corresponding to cardiac activity of the heart of the patient and periodically analyze a most recent electrical signal of the obtained electrical signals to detect an electrical conduction abnormality of the heart. The IMD adjusts a frequency at which the most recent electrical signal is analyzed based on at least one physiological parameter of the patient. For example, the IMD may increase the frequency at which the most recent electrical signal is analyzed when a heart rate parameter has significantly changed and the number of detected premature ventricular contractions (PVCs) is greater than or equal to a threshold number. In this manner, the most recent electrical signal is analyzed at a higher frequency in situations in which conduction abnormalities are more likely.

Abstract: Delivery of fusion pacing therapy to a later depolarizing ventricle (V2) of a heart of a patient may be timed based on the depolarization of the V2 during at least one prior cardiac cycle. In some examples, a V2 pacing pulse is delivered upon the expiration of a pacing interval that begins at detection of an atrial sense or pace event (AP/S). The pacing interval may be substantially equal to the duration of time between an AP/S and a V2 sensing event of at least one prior cardiac cycle decremented by an adjusted pre-excitation interval (PEI). In another example, the V2 pacing pulse is delivered at the expiration of a pacing interval that begins upon detection of a V2 sensing event of a prior cardiac cycle. The pacing interval may be substantially equal to a duration of time at least two subsequent V2 sensing events decremented by the adjusted PEI.

Abstract: The disclosure provides methods and apparatus of left ventricular pacing including automated adjustment of a atrio-ventricular (AV) pacing delay interval and intrinsic AV nodal conduction testing. It includes—upon expiration or reset of a programmable AV Evaluation Interval (AVEI)—performing the following: temporarily increasing a paced AV interval and a sensed AV interval and testing for adequate AV conduction and measuring an intrinsic atrio-ventricular (PR) interval for a right ventricular (RV) chamber. Thus, in the event that the AV conduction test reveals a physiologically acceptable intrinsic PR interval then storing the physiologically acceptable PR interval in a memory structure (e.g., a median P-R from one or more cardiac cycles). In the event that the AV conduction test reveals an AV conduction block condition or if unacceptably long PR intervals are revealed then a pacing mode-switch to a bi-ventricular (Bi-V) pacing mode occurs and the magnitude of the AVEI is increased.

Abstract: Provided herewith are methods and apparatus for optimizing ventricle-to-ventricle (V-V) pacing delay intervals based upon ECG-based optimization calculated as a linear function of P-wave duration sensed PR (intrinsic) interval sensed (or paced) QRS duration and heart rate. Since the relationship among these parameters is linear once the coefficients are solved (which can be any value, including null) with reference to a known optimized V-V interval such as from an echocardiographic study, an operating V-V interval value can be dynamically adjusted in an ambulatory subject. The various combinations of values can be loaded into a look up table or calculated automatically. And, since some of the parameters do not typically change much over time they can be determined acutely and fed into the equation while the other values can be measured more frequently. The parameter values can be measured by an implantable medical device such as a dual- or triple-chamber pacemaker.

Abstract: Novel methods and apparatus for dynamically monitoring paced and sensed P-wave duration, P-wave end and/or QRS duration and/or S-T segment duration, or length, in a patient having an implantable medical device (IMD) provides diagnostic and clinical benefit allowing for predictions about future arrhythmia, advanced notification, alert and intervention as well as providing acute and chronic information regarding cardiac status, including both possibly declining and/or improving cardiac function. The methods can be performed using a wide variety of IMDs, such as pacemakers, cardiac resynchronization therapy (CRT) device, implantable cardioverter defibrillators (ICDs), and implantable loop recorders (e.g., such as the REVEALS device manufactured by Medtronic, Inc.).

Abstract: A medical device and method for determining a parameter for delivery of a predetermined pacing therapy that includes a plurality of electrodes to deliver a pacing therapy, including the predetermined pacing therapy, and a control unit to control the timing of the delivery of the pacing therapy, including the predetermined pacing therapy, by the electrodes. A processor generates a first template in response to the pacing therapy being delivered to only one of a right ventricle and a left ventricle, and a second template in response to the pacing therapy being delivered to only the other of the right ventricle and the left ventricle, and determines the parameter in response to a comparing of subsequently delivered pacing therapy to the first template and the second template.

Abstract: Provided herewith are methods and apparatus for optimizing an atrioventricular (AV) pacing delay interval. One manner described involves programming an AV interval in such a way that the time interval between the end of the P-wave (PWend) and the beginning of the QRS complex (QRSbeg) or ventricular pace stimulus (Vp) is close to or no less than a certain fixed value (e.g. 40 ms). This is defined as an optimized AV interval (AVopt) herein. The foregoing can be dynamically and chronically implemented in an implantable medical device such as a dual- or triple-chamber pacemaker. The PWend value is detected using a novel technique and sensing QRSbeg and/or Vp is achieved with traditional circuitry and components. Then automatic adjustment of an operating AV interval occurs until AVopt is identified. Thereafter, periodic, continuous, or manually-triggered performance of the foregoing can be implemented.

Abstract: Provided herewith are methods and apparatus for optimizing an atrioventricular (AV) pacing delay interval. One manner described involves dynamically programming an AV interval in cardiac resynchronization therapy (CRT) device having a rate-adaptive AV (RAAV) feature in such a way that not less than a minimum AV interval is maintained. That is, the AV interval is not allowed to be reduced so much that the P-wave is truncated by the QRS complex. In this form of the invention, the AV interval is reduced by one millisecond per one bpm increase in heart rate (and vice versa for reducing heart rate) but maintained at a value calculated from the end of the P-wave (PWend) and the beginning of the QRS complex (QRSbeg) or delivery of a ventricular pacing stimulus or to the end of the end of the QRS complex (QRSend).

Abstract: Provided herewith are methods and apparatus for optimizing an atrioventricular (AV) pacing delay interval based upon ECG-based optimization is calculated as a linear function of P-wave duration, sensed PR (intrinsic) interval, sensed or paced QRS duration and heart rate. Since the relationship among these parameters is linear, once the coefficients are solved (which can be any value, including null) with reference to a known optimized AV interval (AVopt) such as from an echocardiographic study, an AVopt value can be dynamically adjusted in an ambulatory subject. The various combinations of values can be loaded into a look up table or calculated automatically. And, since some of the parameters do not typically change much over time they can be determined acutely and fed into the equation while the other values can be measured frequently. The parameter values can be measured by an implantable medical device such as a dual- or triple-chamber pacemaker.

Abstract: A medical device system and method for delivering mechanically fused left ventricular cardiac stimulation. A sensor monitors left ventricular acceleration while left ventricular cardiac stimulation is provided at an AV interval. The left ventricular acceleration is used to calculate a mechanical response interval and the mechanical response interval is compared to a desired mechanical response interval. The AV interval is adjusted until the mechanical response interval is equal to the desired mechanical response interval.