68 results about "Bi ventricular" patented technology

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=systolic P-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 (.tau.); (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.sub.ES), 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.

A bi-atrial and/or bi-ventricular patient safety cable includes a multi-conductor insulated external cable having a Y-connector portion, an external lead connector assembly, and two or more lead adaptors. The patient safety cable is used to electrically connect one or more implantable leads "in parallel" to an external medical device.

The present invention provides a technique for verifying pacing capture of a ventricular chamber, particularly to ensure desired delivery of a ventricular pacing regime (e.g., “CRT”). The invention also provides ventricular capture management by delivering a single ventricular pacing stimulus and checking inter-ventricular conduction during a temporal window to determine if the stimulus captured. If a loss-of-capture (LOC) signal results from the capture management testing, then the applied pacing pulses are modified and the conduction test repeated. If LOC, an alert message can issue. Other aspects include: use of a trend of A-RV/LV and LV-RV timing intervals to monitor changes in the patient's heart conduction properties; bi-ventricular verification test and search—while still pacing BiV by detecting latent sense; single-V pacing threshold search, use of timing of sense in other V chamber to establish capture and LOC windows; (iv) use of a premature V pace rather than short AV interval if VV cannot be discriminated from AV; (v) option to run a threshold search only if the Bi-ventricular verification test fails.

An implantable cardiac therapy device and methods of using a device including an implantable stimulation pulse generator, one or more implantable leads defining sensing and stimulation circuits adapted to sense and deliver therapy in at least one right side heart chamber, and an implantable controller in communication with the stimulation pulse generator and the one or more patient leads so as to receive sensed signals indicative of a patient's physiologic activity and deliver indicated therapy. The controller is adapted to monitor at least one indicator of cardiac dysynchrony and to compare the at least one indicator to a determined dysynchrony threshold. The threshold is determined for indications that the patient be further evaluated for cardiac resynchronization therapy. The controller is further adapted to set an alert when the at least one indicator exceeds the threshold to indicate to a clinician that evaluation for bi-ventricular pacing might be indicated.

Techniques are presented for providing adjustable cardiac resynchronization with an implanted medical device such as a pacemaker. For example, cardiac resynchronization may be provided during some time periods but not during other time periods, or cardiac resynchronization may be provided in response to selected sensed events. Adjustable cardiac resynchronization is applicable to therapy such as bi-ventricular pacing, in which both ventricles of the heart are paced in response to sensed atrial events.

An apparatus for determining tissue versus fluid components of an organ include a detector that generates a detector signal based on electrical signals derived from tissue and fluid. The apparatus includes a signal processor in communication with the detector which subtracts in real time a tissue component from the detector signal and produces a fluid volume signal. A method for monitoring a patient's fluid volume of a patient's organ. An apparatus for monitoring a patient's organ. A method for monitoring a patient's organ. A method to piggyback an admittance system onto a AICD/Bi-ventricular Pacemaker for a heart of a patient, in particular a weakened heart having features consistent with congestive heart failure. An apparatus for monitoring an organ, such as a heart, lungs, brain, skeletal muscle, and bladder of a patient which includes a detector which detects the admittance of the organ. The apparatus includes a transmitter in communication with the detector which transmits a wireless signal indicative of the admittance of the organ. A method for monitoring an organ of a patient includes the steps of detecting with a detector the admittance of the organ. There is the step of transmitting with a transmitter in communication with the detector a wireless signal indicative of admittance of the organ.

The present invention enables hemodynamic efficiencies for patients suffering from intraventricular conduction delays or conduction blockage. The invention effectively overcomes such conduction delay or block (e.g., left bundle branch block, “LBBB,” or right bundle branch block, “RBBB”) by delivering a novel form of cardiac resynchronization therapy (CRT). Specifically, a single ventricular pre-excitation pacing stimulus is triggered from an atrial event (e.g., intrinsic or evoked depolarization). The triggering event may emanate from the right atrium (RA) or the left atrium (LA). A single ventricular pre-excitation pacing stimulus is delivered prior to the intrinsic depolarization of the other ventricle and thus promotes intraventricular electromechanical synchrony during CRT delivery.

An apparatus for treating a heart of a patient includes a first lead and at least a second lead for pacing the heart adapted to be in electrical communication with the heart. The apparatus includes a microcontroller in communication with the first and second leads which triggers the first lead at either different times or the same time from when the microcontroller triggers the second lead. Alternatively, the apparatus includes a microcontroller in communication with the first and second leads that determines heart volume, including stroke volume, end-systolic volume, and calculated values including ejection fraction, from admittance from signals from the first and second leads and uses the admittance as feedback to control heart volume ejected, as measured by stroke volume, calculated values such as ejection fraction, and control end-systolic volume, with respect to the first and second leads. A method for treating the heart of a patient.

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.

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.

The present invention provides a pacing device and method that allows for preferential right atrial, at or near the His bundle, and ventricular pacing, either individually or in combination, including tri-ventricular pacing. The pacing device includes a power source and one or more logic circuits allowing for programmable delivery of pacing to any combination of the right atria, the para-Hisian region, and the right and/or the left ventricles. The pacing device allows the user to select which site(s) to pace as well at the appropriate relative timing of pacing impulse delivery to any of these three previously mentioned sites. The device is constructed and arranged to be combined with an atrial sensing/pacing electrode to allow for atrio-ventricular sequential tri-ventricular pacing or variants of such. Also, a defibrillator lead can be incorporated into the device to allow for protection from ventricular arrhythmias and sudden death.

Improved methods and devices perform anti-tachycardia pacing (ATP) to convert a ventricular tachycardia (VT) to normal sinus rhythm. In one embodiment of the invention bi-ventricular (BV) ATP is employed. In this embodiment the right ventricle and left ventricle of a patient's heart are independently paced based on signals sensed in each chamber.

An implantable bi-ventricular heart stimulating device has a control circuit that within a time cycle, delivers pacing pulses with both first and second pacing circuits with a time gap between a pacing pulse delivered by these pacing circuits. The time gap can be such that a pacing pulse delivered by the second pacing circuits falls substantially within a first time interval in which an evoked response can be expected to a pacing pulse delivered by the first pacing circuit. The control circuit performs a temporary modification of the operation of the device such that during at least one time cycle no pacing pulse is delivered by the second pacing circuit during the first time interval.

An apparatus for determining heart transplant rejection of a heart in a patient includes at least two electrodes adapted to be sewn into the heart that span the left ventricle. The apparatus includes a voltage generator adapted to be inserted in the patient which generates a voltage to the two electrodes and senses the resulting voltage from the two electrodes. A method for determining heart transplant rejection of a heart in a patient. A pacemaker for a patient (including bi-ventricular pacing and AICDs). The pacemaker includes an RV lead having four electrodes adapted to be inserted into the RV apex. The pacemaker includes a voltage generator which generates a voltage signal to the electrodes and senses the instantaneous voltage along the length of the RV and determines the real and imaginary components to remove the myocardial components of the septum and RV free wall to determine absolute RV blood volume. The pacemaker includes a battery connected to the voltage generator. The pacemaker includes a defibrillator connected to the battery. The pacemaker can also be a bi-ventricular pacemaker to restore RV and LV synchrony during contraction. A method for assisting a heart of a patient.