Abstract: A method and apparatus for adjusting the electrogram (EGM) sensitivity level of an implantable medical device using intracardiac pressure data. An EGM is monitored to detect electrical events and intracardiac pressure is monitored to detect pressure waves. The electrical waves and pressure waves are analyzed to determine the presence of a one-to-one correlation, with the absence of a one-to-one correlation indicating the need to adjust the sensitivity level.

Abstract: An medical electrical lead in embodiments of the teachings may include one or more of the following features: (a) a lead body having a proximal end and a distal end, (b) a conductor traversing from the proximal end to the distal end, (c) an electrode disposed at the distal end of the lead body and electrically coupled to the conductor adapted to electrically stimulate a heart, (d) occlusion fabric disposed at the distal end of the lead body and supported by the electrode in a shape adapted to cover holes in the heart, and (f) a second electrode adapted to provide bipolar electrical stimulation of the heart.

Abstract: The hemodynamic operation of certain heart disease patient can be improved using pressure regulated atrio-ventricular delay. The pressure regulated atrio-ventricular delay involves recording atrial activation and ventricle activation, identifying a maximum diastolic pressure, identifying a declination pressure, calculating a percent decrease, and adjusting atrio-ventricular delay. The declination pressure occurs at the beginning of an isovolumetric contraction. The percent decrease is calculated between the maximum diastolic pressure and the declination pressure. The atrio-ventricular delay is adjusted according to the percent decrease between the maximum diastolic pressure and the declination pressure.

Abstract: An improved pacemaker has a hysteresis feature that activates accelerated pacing during periods of sinus arrest and/or extreme bradycardia. When the patient's intrinsic heart rate drops below a hysteresis rate, the pacemaker reverts to a programmable accelerated rate or to the average cardiac rate. Accelerated pacing is delivered for a programmable period of time, after which the pacing rate is gradually reduced toward a lower rate. If a desirable intrinsic rate is not attained after the pacing rate is reduced to the lower rate, the intervention cycle repeats.

Abstract: A method for pacing a left ventricle of a heart includes delivering a pacing pulse via a first electrode to activate a first papillary muscle and another pacing pulse via a second electrode to activate a second papillary muscle.

Abstract: A medical electrical trans-septal pacing lead includes a lead body, a tine-like structure terminating a distal end of the lead body and a distal electrode coupled to the lead body at a position proximal to and in close proximity to the structure. A method for delivering left ventricular pacing to a heart includes inserting the trans-septal pacing lead through an inter-ventricular septal wall of the heart, from a right ventricle to a left ventricle, and positioning the distal electrode in a left ventricular endocardial surface of the septal wall.

Abstract: The hemodynamic operation of certain heart disease patient can be improved using pressure regulated atrio-ventricular delay. The pressure regulated atrio-ventricular delay involves recording atrial activation and ventricle activation, identifying a maximum diastolic pressure, identifying a declination pressure, calculating a percent decrease, and adjusting atrio-ventricular delay. The declination pressure occurs at the beginning of an isovolumetric contraction. The percent decrease is calculated between the maximum diastolic pressure and the declination pressure. The atrio-ventricular delay is adjusted according to the percent decrease between the maximum diastolic pressure and the declination pressure.

Abstract: An introducer system for performing lead replacement includes a reclosable, split sheath introducer. The sheath may preferably be a two-part sheath assembled around an implanted lead body and advanced into an existing venous entry point over an implanted lead. The sheath may optionally be provided with a distal dissecting edge to aid in advancing the introducer through fibrous tissue that may adhere or interfere with the lead. The implanted lead may be removed and a replacement lead may be introduced through the same venous entry point via the introducer. The introducer may then be withdrawn and disassembled from the replacement lead. In alternative embodiments, the introducer may preferably include a one-part sheath having curvilinear overlapping flaps that enclose the sheath lumen but may be parted to allow assembly of the introducer over an implanted lead. Another embodiment of the present invention provides a reclosable, split guide catheter.

Abstract: In a system that includes a ventricular pacemaker, the system adjusts an atrioventricular delay to synchronize the onset of isovolumetric contraction with the completion of ventricular filling. The system adjusts the atrioventricular delay as a function of electrical and pressure data from the heart. The system further adjusts the atrioventricular delay as a function of measurements of the time interval between a cardiac occurrence such as a ventricular pace and the completion of ventricular filling. The system may also adjust the atrioventricular delay as a function of the heart rate.

Abstract: A pacemaker provides multi-chamber pacing with a pacing interval that can be programmed and adapted in response to cardiac output measurements for a given patient. In a typical embodiment, the pacemaker may provide pacing stimuli to both ventricles of a heart. In addition, the invention may include a measurement device that incorporates first and second blood oxygen saturation sensors for deployment in the left and right ventricle. The oxygen saturation sensors provide a differential measurement that can be used to calculate cardiac output in accordance with the Fick method. The oxygen saturation sensors may be carried by a common trans-septal lead that positions one of the sensors proximate the right ventricle and the other sensor proximate the left ventricle. Alternatively, the oxygen saturation sensors may be deployed via separate leads. Whether single or dual leads are used to carry the oxygen saturation sensors, a respective lead may optionally carry electrodes for sensing, pacing, or both.

Abstract: In one embodiment, a method includes sensing depolarizations of a heart at a plurality of different locations, and determining a sequence of the sensed depolarizations. The method may further include identifying a tachycardia condition and stimulating the heart at the plurality of locations based on the determined sequence. For example, the method may be implemented by an implantable medical device in order to improve anti-tachycardia pacing (ATP).

Abstract: Techniques for pacing the heart of a patient as a function of a pressure value make use of a pressure monitor that receives a signal from a pressure sensor in the heart. The pressure monitor measures a pressure value. The pressure monitor may, for example, estimate the pulmonary artery diastolic pressure if the pressure sensor is located in the right ventricle, or calculate the mean central venous pressure if pressure sensor is located in the right atrium. The energy level of the pacing pulses delivered to the patient's heart by a pacemaker is modulated as a function of the pressure value. Modulating the energy level of the pacing pulses modulates the cardiac output of the patient's heart.

Abstract: The invention is directed to techniques for monitoring the condition of a patient, such as a patient having congestive heart failure, and appropriately modifying the patient's drug therapy as a function of a pressure in the patient's heart, such as the estimated pulmonary artery diastolic pressure. The drugs may be administered by an implanted drug delivery device. The drug selection, the drug dosage or both may be controlled as a function of the pressure and/or the activity level of the patient.

Abstract: An implantable medical device and method of pacing provide for switching from a first pacing mode to second pacing mode upon detection of a period of accelerated atrial arrhythmia. Generally, the second pacing mode has an associated predetermined lower pacing rate. At least initially, upon switching from the first pacing mode to the second pacing mode, the predetermined lower pacing rate is adjusted to an elevated adjusted lower rate. Further, this elevated adjusted lower rate may then be decelerated towards a programmed basic pacing rate during a deceleration period. Generally, the programmed basic pacing rate is elevated relative to the predetermined lower pacing rate.

Abstract: An improved pacemaker has a hysteresis feature that activates accelerated pacing during periods of sinus arrest and/or extreme bradycardia. When the patient's intrinsic heart rate drops below a hysteresis rate, the pacemaker reverts to a programmable accelerated rate or to the average cardiac rate. Accelerated pacing is delivered for a programmable period of time, after which the pacing rate is gradually reduced toward a lower rate. If a desirable intrinsic rate is not attained after the pacing rate is reduced to the lower rate, the intervention cycle repeats.

Abstract: 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.

Abstract: An implantable medical device and method of pacing provide for switching from a first pacing mode to second pacing mode upon detection of a period of accelerated atrial arrhythmia. Generally, the second pacing mode has an associated predetermined lower pacing rate. At least initially, upon switching from the first pacing mode to the second pacing mode, the predetermined lower pacing rate is adjusted to an elevated adjusted lower rate. Further, this elevated adjusted lower rate may then be decelerated towards a programmed basic pacing rate during a deceleration period. Generally, the programmed basic pacing rate is elevated relative to the predetermined lower pacing rate.

Abstract: 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.

Abstract: Multi-chamber cardiac pacing systems for providing synchronous pacing to at least the two upper heart chambers or the two lower heart chambers or to three heart chambers or to all four heart chambers employing programmable conduction delay window (CDW) times timed out from paced and sensed events occurring in each heart chamber are disclosed. The synchronous pacing of one of the right and left heart chambers is provided on demand following expiration of programmable pace and sense CDWs that are started by both a paced event and a sensed event first occurring in the other of the right and left heart chambers. The delivery of the pacing pulse is inhibited by a sensed event detected in the other of the right and left heart chambers before the expiration of the corresponding CDW.

Abstract: Multi-chamber cardiac pacing systems for providing synchronous pacing to at least the two upper heart chambers or the two lower heart chambers or to three heart chambers or to all four heart chambers employing programmable conduction delay window (CDW) times timed out from paced and sensed events occurring in each heart chamber are disclosed. The synchronous pacing of one of the right and left heart chambers is provided on demand following expiration of programmable pace and sense CDWs that are started by both a paced event and a sensed event first occurring in the other of the right and left heart chambers. The delivery of the pacing pulse is inhibited by a sensed event detected in the other of the right and left heart chambers before the expiration of the corresponding CDW.