35 results about "Ventricular conduction" patented technology

A system and method are provided for controlling atrial anti-tachycardia pacing (ATP) delivery based on detection of ventricular pro-arrhythmia during or immediately after atrial ATP. Ventricular pro-arrhythmia is detected based on one or more criteria relating to pro-arrhythmic changes including, but not limited to, ventricular rate changes, R-wave morphology changes, and/or 1:1 or nearly 1:1 atrial-ventricular conduction patterns persisting at high ventricular rates. Upon detecting ventricular pro-arrhythmia, a current atrial ATP sequence is aborted. Atrial ATP therapies may subsequently be temporarily or permanently disabled.

An exemplary method includes delivering a cardiac resynchronization therapy using an atrio-ventricular delay parameter and an interventricular delay parameter, measuring an atrio-ventricular conduction delay, measuring an interventricular conduction delay, assessing heart failure and/or cardiac resynchronization therapy performance based at least in part on the measured atrio-ventricular conduction delay and the measured interventricular conduction delay and determining at least one of an atrio-ventricular delay parameter value and an interventricular delay parameter value based at least in part on the measured atrio-ventricular conduction delay and the measured interventricular conduction delay. Other exemplary technologies are also disclosed.

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.

The present invention is applicable to the field of medical technology and provides a method and a device for identifying atrial fibrillation with ventricular premature contraction and atrial fibrillation with aberrant ventricular conduction. The method comprises the following steps: acquiring electrocardiosignals; determining atrial fibrillation with wide QRS waves in the electrocardiosignals; extracting feature values of the atrial fibrillation with the wide QRS in the electrocardiosignals; obtaining a recognition result by an identification algorithm model based on the feature values; identifying the atrial fibrillation with the ventricular premature contraction and the atrial fibrillation with the aberrant ventricular conduction by using the identification algorithm model; and improving recognition accuracy and recognition efficiency of the atrial fibrillation with the ventricular premature contraction and the atrial fibrillation with the aberrant ventricular conduction. The methodsolves a problem that the electrocardiosignals of the atrial fibrillation with the ventricular premature contraction and the electrocardiosignals of the atrial fibrillation with the aberrant ventricular conduction cannot be accurately identified and distinguished in the prior art.

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., cardiac resynchronization therapy or “CRT”). The invention also provides for ventricular capture management by delivering a single ventricular pacing stimulus and checking inter-ventricular conduction during a temporal window to determine if the ventricular pacing stimulus captured the chamber. If a loss-of-capture (LOC) signal results from the capture management testing, then the characteristics of the applied pacing pulses are modified and the conduction test repeated. In the event that the LOC signal persists, a pacing mode-switch to an atrial-based pacing therapy and/or non-bi-ventricular pacing regimen can be implemented.

In bi-ventricular pacing devices (including CRT devices) analysis of myocardial electrogram signals in one ventricle (e.g., a left ventricle, or “LV”) can be used to infer capture or loss-of-capture (LOC) of an earlier stimulus pulse in the same ventricle, on a continuous (every pacing cycle), triggered, aperiodic and/or periodic basis. Rather than using an evoked-response principle as has been the basis of capture detection in prior art and other systems, a principle employed via the present invention uses evidence of inter-ventricular conduction (i.e., from the opposite chamber) and/or atrio-ventricular conduction as evidence of LOC, since a non-capturing pacing stimulus provided to a first chamber will allow the myocardial tissue of the first chamber to remain non-refractory and thus inter-ventricular and atrio-ventricular wavefront propagation and conduction can commence and be detected thereby revealing whether LOC has occurred.

An implantable pacing system with single, double and triple chamber pacing capabilities, provided individually or in concert on a conditional or continuous basis depending upon ongoing analyses of atrial rhythm status, atrioventricular conduction status and ventricular rate. A mode is selected to reduce the occurrence of any ventricular pacing in favor of intrinsic atrioventricular and ventricular conduction. If excessively long PR intervals are occurring too frequently or atrioventricular conduction is unreliable or absent, the implantable pulse generator is operated in a conditional triple chamber pacing mode that provides atrial-synchronous biventricular pacing in every cardiac cycle for a period of time as necessary to restore and maintain AV synchrony, while minimizing ventricular asynchrony otherwise associated with monochamber RV pacing as in conventional dual chamber pacing systems. Similarly, biventricular pacing is provided in every cardiac cycle when ventricular rates are undesirably slow during atrial fibrillation, where AV synchronization is excluded.

Methods and systems are provided for a rate adaptive bi-ventricular fusion pacing. The methods and systems deliver a first pulse at a left ventricular (LV) lead and a second pulse at a right ventricular (RV) lead based on a paced atrio-ventricular (AV) delay. The first pulse timed to be delivered concurrently with an intrinsic ventricular conduction. The methods and systems further repeat the delivery of the first pulse and the second pulse for a predetermined number of cycles. Additionally, the methods and systems measure an intrinsic AV conduction interval, and adjust the paced AV delay based on the intrinsic AV conduction interval and a negative hysteresis delta.

Systems and methods for detecting cardiac arrhythmias such as an atrial fibrillation (AF) are described herein. The AF detection system includes a sensor circuit to sense a physiological signal, a heartbeat processor to recognize a plurality of beat patterns using cycle length of two more consecutive cardiac cycles. The beat patterns can be indicative of temporal relationship between the consecutive cardiac cycles. The heartbeat processor may generate a repetitiveness indictor based on a statistical measurement of various beat patterns. The AF detection system includes an arrhythmia detector to detect an episode of AF based on the repetitiveness indictor, and to discriminate the AF from other arrhythmias of atrio-ventricular conduction abnormalities.

The disclosure describes techniques for delivering electrical stimulation to decrease the ventricular rate response during an atrial tachyarrhythmia, such as atrial fibrillation. AV nodal stimulation is employed during an atrial tachyarrhythmia episode with rapid ventricular conduction to distinguish ventricular tachyarrhythmia from supraventricular tachycardia and thereby prevent delivering inappropriate therapy to a patient.

An improvement to the GiWi protocol for differentiating human pluripotent cells to developmentally mature cardiomyocytes includes a step of activating innate immunity in mesoderm stage cells in the in vitro differentiation culture. When the mesoderm cells, which are precursors to cardiac progenitor cells, are primed by exposure to an activator of innate immunity, a population of cardiomyocytes is generated that is more developmentally mature than is generated in the GiWi protocol without the primed step. Also provided herein are in vitro ventricular conductive microtissues and isolated, in vitro populations of ventricular conduction system-like cells and methods for making the same.

The invention provides a cardiac pacemaker which comprises a control module and a perception module. The cardiac pacemaker can be switched into second modes to work during atria ventricular block, atria ventricular conduction recovery can be simultaneously detected by the perception module under the control of the control module by means of AV (atria ventricular) conduction section search according to preset periods, the cardiac pacemaker can be switched into first modes to work when atria ventricular conduction recovery is detected by the perception module, the preset periods include C waiting intervals which are sequentially arranged, a waiting interval is available after each section of AV conduction section search, each later waiting interval is not shorter than the corresponding previous waiting interval, and the last waiting interval in the preset periods is longer than the first waiting interval. Compared with existing cardiac pacemakers, the cardiac pacemaker in the configuration has the advantages that the cardiac pacemaker is reasonable in atria ventricular conduction recovery detection frequency, and right ventricular pacing can be reduced as far as possible on the basisthat the atria ventricular stability is guaranteed.