摘要:
Systems and methods are provided for detecting the orientation and/or movement of a patient having an implantable cardiac stimulation device and evaluating whether a change in the patient's cardiac activity can be at least in part due to a change in the patient's orientation. In one particular embodiment, signals from an orientation sensor and/or a pressure sensor are evaluated to determine static positional orientation of the patient and determine based on the static orientation whether the patient's cardiac activity is abnormal.
摘要:
A leadless intra-cardiac medical device (LIMD) configured to be implanted entirely within a heart of a patient includes a housing configured to be securely attached to an interior wall portion of a chamber of the heart, and a stabilizing intra-cardiac (IC) device extension connected to the housing. The stabilizing IC device extension may include a stabilizer arm, and/or an appendage arm, or an elongated body or a loop member configured to be passively secured within the heart.
摘要:
A leadless intra-cardiac medical device includes a housing that is configured to be implanted entirely within a single local chamber of the heart. A first electrode is provided on the housing at a first position such that when the housing is implanted in the local chamber, the first electrode engages the local wall tissue at a local activation site within the conduction network of the local chamber. An intra-cardiac extension is coupled to the housing and configured to extend from the local chamber into an adjacent chamber of the heart. A stabilization arm of the intra-cardiac extension engages the adjacent chamber. A second electrode on the intra-cardiac extension engages distal wall tissue at a distal activation site within the conduction network of the adjacent chamber.
摘要:
An implantable physiologic sensor assembly is configured to be implanted within a patient. The assembly includes a module that houses an internal operative chamber, and a flexible pressure-detecting member connected to the module. The module and the pressure-detecting member are separated before implantation into the patient. At least a first end of the pressure-detecting member is configured to be inserted into an artery of the patient and a second end of the pressure-detecting member is connected to the module. The module is configured to be subcutaneously positioned within the patient.
摘要:
A communication circuit of an implantable device is coupled to a power source (e.g., including a battery) upon receipt of a radiofrequency (RF) signal at the implantable device. A circuit that controls whether the communication circuit is to be coupled to the power source obtains its power from the received RF signal. Thus, the implantable device is able to perform RF signal monitoring (e.g., RF “sniffing”) without using battery power. Battery power is then used for subsequent communication operations after it has been determined that the implantable device is receiving RF signals (e.g., from a verified external device).
摘要:
Techniques are provided for use by an implantable medical device for optimizing the amount of ventricular dyssynchrony induced within a patient during protective pacing. In one example, the device analyzes intracardiac electrogram signals to detect an ischemic event within the heart. The device then delivers pacing stimulus in accordance with adjustable pacing parameters to induce ventricular dyssynchrony within the heart and adjusts the pacing parameters within a range of permissible values to achieve a preferred degree of ventricular dyssynchrony within the patient, so long as there is no significant reduction in left ventricular pumping functionality. Preferably, the pacing parameters are adjusted to maximize or otherwise optimize the degree of dyssynchrony induced within the patient. If a significant reduction in LV pumping functionality is detected, the dyssynchrony-inducing pacing is preferably suspended to avoid any deterioration in the condition of the heart. Techniques for detecting early onset of ischemia are also disclosed.
摘要:
A leadless intra-cardiac medical device (LIMD) includes multiple electrodes that allow for stimulation and sensing of the right ventricle (RV) and sensing of the right atrium (RA), even though it is entirely located in the RV. The LIMD includes a housing having a proximal end configured to engage local tissue in the local chamber and electrodes located at multiple locations along the housing. Sensing circuitry is configured to define a far field (FF) channel between a first combination of the electrodes to sense FF signals occurring in the adjacent chamber. The sensing circuitry is configured to define a near field (NF) channel between a second combination of the electrodes to sense NF signals occurring in the local chamber. A controller is configured to analyze the NF and FF signals to determine whether the NF and FF signals collectively indicate that a validated event of interest occurred in the adjacent chamber.
摘要:
An assembly for introducing a leadless intra-cardiac medical device includes a sheath having an internal passage, wherein the sheath is configured to be maneuvered into the heart of the patient. A housing may be retained within the internal passage, wherein the housing is configured to be pushed out of the sheath, the housing having a first anchoring member configured to anchor the housing to a first implant location within the heart. The assembly may also include an electrode trailing the housing within the internal passage, wherein the electrode is also configured to be pushed out of the sheath. The electrode has a second anchoring member configured to anchor the electrode to a second implant location within the heart. A conductive wire connects the housing to the electrode, wherein movement of the housing out of the sheath causes the electrode to follow the movement to a distal end of the sheath.
摘要:
Techniques are provided for use with an implantable medical device for detecting and assessing heart failure and for controlling cardiac resynchronization therapy (CRT) based on impedance signals obtained using hybrid impedance configurations. The hybrid configurations exploit right atrial (RA)-based impedance measurement vectors and/or left ventricular (LV)-based impedance measurement vectors. In one example, current is injected between the device case and a ring electrode in the right ventricle (RV) or RA. RA-based impedance values are measured along vectors between the device case and an RA electrode. LV-based impedance values are measured along vectors between the device case and one or more electrodes of the LV. Heart failure and other cardiac conditions are detected and tracked using the measured impedance values. CRT delay parameters are also optimized based impedance. In this manner, multiple hybrid impedance measurement configurations are exploited whereby different vectors are used to inject current and measure impedance.
摘要:
Disclose herein is a method of measuring pressures in a coronary sinus. In one embodiment, the method includes: introducing a distal portion of a lead or tool into the coronary sinus, wherein the distal portion includes first and second pressure sensors and at least one selectably expandable member; expanding the at least one expandable member such that the first and second sensors are isolated from each other within the coronary sinus; and taking pressure measurements with the first and second sensors when isolated from each other.