摘要:
A system and method for identifying patients with asynchronous ventricular contractions due to abnormal electro-mechanical coupling and computing optimal pacing parameters for restoring synchronous contractions is disclosed. Such patients may have normal intra-ventricular and inter-ventricular conduction and cannot be identified from intrinsic conduction data alone such as QRS width. Techniques for computing optimal resynchronization pacing in order to compensate for abnormal electro-mechanical coupling are also described.
摘要:
A pacing system computes optimal cardiac resynchronization pacing parameters using intrinsic conduction intervals. In various embodiments, values for atrio-ventricular delay intervals are each computed as a function of an intrinsic atrio-ventricular interval and a parameter reflective of an interventricular conduction delay. Examples of the parameter reflective of the interventricular conduction delay include QRS width and interval between right and left ventricular senses.
摘要:
A method is presented by which an implantable cardiac rhythm management device may vary the atrio-ventricular delay or AVD interval used for delivering cardiac resynchronization therapy in an atrial tracking or AV sequential pacing mode in accordance with the sensed or paced atrial rate. Optimal values for the AVD parameter associated with a particular atrial rate are computed as linear functions of an intrinsic conduction measurement taken when the particular rate is present.
摘要:
A method and system for identifying and assessing inter-atrial conduction delays in patients is disclosed. Patients who are so identified and are also in need of ventricular resynchronization therapy may then be treated with left atrial pacing and ventricular resynchronization pacing. Certain patients may alternatively be treated with ventricular resynchronization therapy delivered with a conservatively selected atrio-ventricular delay interval and without left atrial pacing.
摘要:
A system and method provides for inhibiting delivery of atrial therapy under certain conditions. Inhibiting delivery of atrial therapy involves developing atrial intervals and ventricular intervals from sensed atrial and ventricular events, respectively. An average atrial rate and an average ventricular rate is developed from a predetermined number of the atrial and ventricular intervals, respectively. Delivery of atrial therapy is inhibited if the average atrial rate fails to exceed the average ventricular rate by at least a predetermined factor.
摘要:
A system and method which employs atrial discrimination algorithms to distinguish between different atrial arrhythmias occurring in a patient for selecting an optimal pacing therapy corresponding to the type of arrhythmia identified. In response to the detection of an atrial rate above the atrial tracking rate, discrimination criteria are applied to a detected atrial activity signal to distinguish between different types of supraventricular tachycardia, such as fast atrial flutter and other atrial flutter at a relatively slower rate, which may be occurring in the patient. The pacer is controlled to provide pacing therapy to a heart in a manner corresponding to the type of supraventricular tachycardia identified. The output of an atrial discrimination algorithm may be tracked and the trend thereof used to improve therapy timing. Various embodiments are disclosed herein.
摘要:
A track assembly for supporting fabric on a surface includes a base track defining a first half of a hinge and a first half of a snapping clamp. The base track preferably includes a tension force dissipater extending from the first half of the hinge. An upper track defines a second half of the hinge and is pivotally connectable to the base track. The upper track defines a second half of the snapping clamp for releasably engaging the fabric. The upper track includes a strut extended downwardly towards the base track such that when high tension forces are applied to the upper track, due to fabric tensioning, the strut contacts the base track and at least partially transmits the tension forces to the surface.
摘要:
A system and method for providing pacing pulses after a cardioversion/defibrillation shock, where the pacing pulses have a pacing rate at an initial value. The pacing rate is decreased from the initial value until at least one intrinsic cardiac contraction is detected. In one embodiment, the pacing rate is decreased by a set amount after pacing a set number of cardiac cycles. Providing the set number of pacing pulses and decreasing the pacing rate by the set amount is then repeated until at least one intrinsic cardiac contraction is detected. An intrinsic cardiac rate is then determined from the at least one intrinsic cardiac contraction. The pacing rate is then increased and maintained to be above (i.e., greater than) the intrinsic cardiac rate.