428 results about "Cardiac functioning" patented technology

The present invention relates to the field of ambulatory and non-invasive monitoring of a plurality of physiological parameters of a monitored individual. The invention includes a physiological monitoring apparatus with an improved monitoring apparel worn by a monitored individual, the apparel having attached sensors for monitoring parameters reflecting pulmonary function, or parameters reflecting cardiac function, or parameters reflecting the function of other organ systems, and the apparel being designed and tailored to be comfortable during the individual's normal daily activities. The apparel is preferably also suitable for athletic activities. The sensors preferably include one or more ECG leads and one of more inductive plethysmographic sensor with conductive loops positioned closely to the individual to preferably monitor at least basic cardiac parameters, basic pulmonary parameters, or both. The monitoring apparatus also includes a unit for receiving data from the sensors, and for storing the data in a computer-readable medium. The invention also includes systems comprising a central data repository for receiving, storing, and processing data generated by a plurality of physiological monitored apparatus, and for making stored data available to the individual and to health care providers.

A method and a device for improving cardiac function are provided. The device is packaged in a collapsed state in an end of a catheter. Portions of a frame construction of the device spring outwardly when the catheter is withdrawn from the device. Anchoring formations on the frame construction secure the frame construction to a myocardium of the heart. A membrane secured to the frame construction then forms a division between volumes of an endocardial cavity of the heart on opposing sides of the membrane.

A system for improving cardiac function is provided. A foldable and expandable frame having at least one anchoring formation is attached to an elongate manipulator and placed in a catheter tube while folded. The tube is inserted into a left ventricle of a heart where the frame is ejected from the tube and expands in the left ventricle. Movements of the elongate manipulator cause the anchor to penetrate the heart muscle and the elongate manipulator to release the frame. The installed frame minimizes the effects of an akinetic portion of the heart forming an aneurysmic bulge.

An implantable device for measuring mechanical heart function of selected heart chambers using a heart contraction detection system that includes a magnetic field sensor. The system may be used for monitoring signs of acute or chronic cardiac heart failure, to enable diagnosis of the condition of the heart, to prescribe appropriate therapies, and to assess delivered pacing therapies. Distance measurements within the heart are made using the magnetic field sensor which is implanted at a sensor site in or on one of the right or left ventricle. A magnet implanted at a site relative to the other of the left or right heart ventricle is sufficiently spaced at a distance that fluctuates with expansion and contraction of the ventricles. The magnetic field sensor provides a sensor output signal having a signal magnitude proportional to the magnetic field strength of the magnet, and which is indicative of changing cardiac dimensions.

This is a support device that prevents, reduces, and delays remodeling of diseased cardiac tissue, and also decreases the impact of such remodeling on collateral tissue is disclosed. The invention further reinforces abnormal tissue regions to prevent over-expansion of the tissue due to increased afterload and excessive wall tension. As a result, the support device prevents phenomenon such as systolic stretch from occurring and propagating. The support structure maintains and restores diastolic compliance, wall motion, and ejection fraction to preserve heart functionality. As such, the support device prevents and treats cardiomyopathy and congestive heart failure.

The patterns of contraction and relaxation of the heart before and during left ventricular or biventricular pacing are analyzed and displayed in real time mode to assist physicians to screen patients for cardiac resynchronization therapy, to set the optimal A-V or right ventricle to left ventricle interval delay, and to select the site(s) of pacing that result in optimal cardiac performance. The system includes an accelerometer sensor; a programmable pace maker, a computer data analysis module, and may also include a 2D and 3D visual graphic display of analytic results, i.e. a Ventricular Contraction Map. A feedback network provides direction for optimal pacing leads placement. The method includes selecting a location to place the leads of a cardiac pacing device, collecting seismocardiographic (SCG) data corresponding to heart motion during paced beats of a patient's heart, determining hemodynamic and electrophysiological parameters based on the SCG data, repeating the preceding steps for another lead placement location, and selecting a lead placement location that provides the best cardiac performance by comparing the calculated hemodynamic and electrophysiological parameters for each different lead placement location.

Systems according to the invention employ an acceleration sensor to characterize displacement and vibrational LV motion, and uses this motion data to characterize the different phases of the LV cycle for analyzing LV function. Systems may identify a target pacing region or regions in the LV or RV using the acceleration sensor by localizing regions of late onset of motion relative to the QRS, or isovolumic contraction, or mitral valve closure, or by pacing of target regions and measuring LV function in response to pacing. Systems further provide an implantable or non-implantable acceleration sensor device for measuring LV motion and characterizing LV function. An implantable myocardial acceleration sensing system (“IAD”) includes at least one acceleration sensor, a data acquisition and processing device, and an electromagnetic, e.g., RF, communication device. The IAD may be integrated into the pacing lead of a CRT device and can operate independently of the CRT IPG.

A pacing system for providing optimal hemodynamic cardiac function for parameters such as contractility (peak left ventricle pressure change during systole or LV+dp / dt), or stroke volume (aortic pulse pressure) using system for calculating atrio-ventricular delays for optimal timing of a ventricular pacing pulse. The system providing an option for near optimal pacing of multiple hemodynamic parameters. The system deriving the proper timing using electrical or mechanical events having a predictable relationship with an optimal ventricular pacing timing signal.

The surgical implantation of a link, which may be in the form of a tether or a looped band, is proposed to connect and reduce the spacing between papillary muscles, to reduce dilation of the left ventricle. The implanted link thus improves heart function by reducing left ventricular failure.

A method and apparatus for monitoring changes in the intra-thoracic pressure of a patient due to the patient's respiratory activity or volumetric changes in the extra-thoracic arterial circulatory system due to cardiac function based on the changes in pressure in the patient's extra-thoracic arterial circulatory system as measured by a plethysmography sensor, such as an photoplethysmograph. A frequency spectrum is generated for the plethysmograph signal and the frequencies of interest is isolated from the frequency spectrum by setting appropriate cutoff frequencies for the frequency spectrum. This isolated frequency is used to filter the plethysmograph signal to provide a signal indicative of the patient's respiratory activity or cardiac function.

The present invention relies on a controller-transmitter device to deliver ultrasound energy into cardiac tissue in order to directly improve cardiac function and / or to energize one or more implanted receiver-stimulator devices that transduce the ultrasound energy to electrical energy to perform excitatory and / or non-excitatory treatments for heart failure. The acoustic energy can be applied as a single burst or as multiple bursts.

A method and apparatus for monitoring changes in the intra-thoracic pressure of a patient due to the patient's respiratory activity or volumetric changes in the extra-thoracic arterial circulatory system due to cardiac function based on the changes in pressure in the patient's extra-thoracic arterial circulatory system as measured by a plethysmography sensor, such as an photoplethysmograph. A frequency spectrum is generated for the plethysmograph signal and the frequencies of interest is isolated from the frequency spectrum by setting appropriate cutoff frequencies for the frequency spectrum. This isolated frequency is used to filter the plethysmograph signal to provide a signal indicative of the patient's respiratory activity or cardiac function. For corrections for breathing frequency roll-off and deviations of the I:E ratio from 1:1.

What is disclosed is a system and method for processing a time-series signal generated by video images captured of a subject of interest in a non-contact, remote sensing environment such that the existence of a cardiac arrhythmia can be determined for that subject. In one embodiment, a time-series signal generated is received. The time-series signal was generated from video images captured of a region of exposed skin where photoplethysmographic (PPG) signals of a subject of interest can be registered. Signal separation is performed on the time-series signal to extract a photoplethysmographic signal for the subject. Peak-to-peak pulse points are detected in the PPG signal using an adaptive threshold technique with successive thresholds being based on variations detected in previous magnitudes of the pulse peaks. The pulse points are then analyzed to obtain peak-to-peak pulse dynamics. The existence of cardiac arrhythmias is determined for the subject based on the pulse dynamics.

A method of analyzing cardiac functions in a subject using a processing system is described. The method may include applying one or more electrical signals having a plurality of frequencies to the subject and detecting a response to the applied one or more signals from the subject. A characteristic frequency can then be determined from the applied and received signals, and at least one component of the impedance (e.g., reactance, phase shift) can be measured at the characteristic frequency. Thus, the impedance or a component of impedance at a characteristic frequency can be determined for a number of sequential time instances. A new characteristic frequency may be determined within a cardiac cycle (e.g., with each sequential time instant) or the same characteristic frequency may be used throughout the cardiac cycle during which instantaneous values of impedance (or a component of impedance) are determined. These instantaneous values may be used to determine one or more indicia of cardiac function.

The effects of acute left ventricular heart failure are mitigated by temporary support of the cardiac function through use of either one or both of an expendable temporary one-way valve positioned in the aorta, having a collapsible frame that is expanded upon deployment, and / or a temporary dilation device positioned in the descending aorta for expanding upon deployment to increase the diameter of the associated portion of the aorta. When used together, the dilation device is positioned distal to the temporary one-way valve.

A pacing system for providing optimal hemodynamic cardiac function for parameters such as ventricular synchorny or contractility (peak left ventricle pressure change during systole or LV+dp / dt), or stroke volume (aortic pulse pressure) using system for calculating atrio-ventricular delays for optimal timing of a ventricular pacing pulse. The system providing an option for near optimal pacing of multiple hemodynamic parameters. The system deriving the proper timing using electrical or mechanical events having a predictable relationship with an optimal ventricular pacing timing signal.

The current invention is an intracardiac pressure guided pacemaker. It has a sensor in pacemaker lead to sense intracardiac pressure, which is used to find the best pacing location in the cardiac chamber and to adjust the timing of pacing signal. It will optimize pacing location and pacing timing and, therefore, optimize resychronization of the contraction of myocardium and interaction between different cardiac chambers. This will improve cardiac function at the same working condition without increase in oxygen demand from myocardium. The pacemaker has a computer program, which, based on intracardiac pressure, can adjust pacing parameters of the pacemaker to optimize resynchronization of the myocardium and interaction between different cardiac chambers automatically at different heart rate and in certain time interval specified by care provider. This also can be achieved by using an interrogator manually. The pacemaker can also store profiles of pacing parameter and intracardiac pressure, which can be retrieved for review to help optimize cardiac performance.

A three-dimensional map of the probability of brain or heart functional states is obtained based on electric or magnetic signals, or a combination of both measured in the surface of body. From signals, the statistical descriptive parameters are obtained and a map of its distribution is calculated. The map is the inverse solution of the problem based upon: a) the restriction of the solution to structures with high probability of generating electric activity using for this restriction an Anatomical Atlas and b) imposing that the solution belong to a pre-specified functional space. The probability is determined that this map belongs to a test group. The spatial and temporal correlations of the map are modeled as well as their dependence on experimental covariables. The resulting probabilities are coded in a pseudocolor scale and they are superimposed on a Anatomical Atlas for their interactive three-dimensional visualization.

An apparatus for determining cardiac performance in the patient involving a conductance catheter (12) for measuring conductance and blood volume in a heart chamber of the patient. The apparatus includes a processor (14) for determining instantaneous volume of the ventricle by applying a non-linear relationship between the measured conductance and the volume of blood in the heart chamber to identify mechanical strength of the chamber. The processor (14) is in communication with the conductance catheter (12).

A noninvasive or minimally invasive treatment of infarct areas of the heart with High Intensity Focused Ultrasound (HIFU) emitted without respect to the timing or phase of the cardiac cycle, intended to remodel cardiac tissue by inducing angiogenesis and / or the formation of myocytes to improve cardiac function.

What is disclosed is a system and method for processing a time-series signal generated by video images captured of a subject of interest in a non-contact, remote sensing environment such that the existence of a cardiac arrhythmia can be determined for that subject. In one embodiment, a time-series signal generated is received. The time-series signal was generated from video images captured of a region of exposed skin where photoplethysmographic (PPG) signals of a subject of interest can be registered. Signal separation is performed on the time-series signal to extract a photoplethysmographic signal for the subject. Peak-to-peak pulse points are detected in the PPG signal using an adaptive threshold technique with successive thresholds being based on variations detected in previous magnitudes of the pulse peaks. The pulse points are then analyzed to obtain peak-to-peak pulse dynamics. The existence of cardiac arrhythmias is determined for the subject based on the pulse dynamics.

An assembly for providing localized pressure to a region of a patient's heart to improve heart functioning, including: (a) a jacket made of a flexible biocompatible material, the jacket having an open top end that is received around the heart and a bottom portion that is received around the apex of the heart; and (b) at least one inflatable bladder disposed on an interior surface of the jacket, the inflatable bladder having an inelastic outer surface positioned adjacent to the jacket and an elastic inner surface such that inflation of the bladder causes the bladder to deform substantially inwardly to exert localized pressure against a region of the heart.

The present invention generally relates to the field of cell growth and tissue engineering, in particular, tissue engineered compositions comprising a nanotextured substrate which is structurally configured for growth of cells in an anatomically correct adult phenotype in vitro. In particular, described herein are nanotextured substrates which are structurally configured for the anisotropic organization, maturation, and growth of in vitro-differentiated muscle cells, such as cardiomyocytes, and methods for the production and use thereof in varying sizes, nanotextures and substrate rigidities. In vitro-differentiated cardiomyocytes grown on the nanotextured substrates described herein are better-differentiated and more closely mimic adult cardiac tissue than the same cells grown on a non-textured substrate of the same composition. The nanotextured substrate / cell constructs provide a platform for screening to predict the effect of test agents or drugs on, for example, human cardiac tissue, including patient-derived tissue, or for the identification of agents that effect various cardiac functional parameters.

Methods and devices for passively assisting the cardiac function of the heart are disclosed. A method of increasing the cardiac output of a heart includes providing a site of surgical access to the portion of the heart to be restrained, reducing the cardiac expansion of the portion of the heart to be restrained, and maintaining the reduction of cardiac expansion of the portion of the heart to be restrained for a substantial amount of time. Cardiac assist devices for increasing the cardiac output of the heart are disclosed comprising a reinforcing portion configured to contact a portion of the heart tissue wherein the reinforcing portion restricts the expansion of the portion of the heart tissue. The reinforcing portion can be a number of structures, including pads, frames, straps, and other retaining means for limiting cardiac expansion of the portion of the heart tissue to be restrained.

A method of real time ultrasound imaging of an object in at least three two-dimensional scan planes that are rotated around a common axis, is given, together with designs of ultrasound transducer arrays that allows for such imaging. The method is also introduced into a monitoring situation of cardiac function where, combined with other measurements as for example the LV pressure, physiological parameters like ejection fraction and muscular fiber stress is calculated.

The present invention describes a device and system for simulating normal and disease state cardiovascular functioning, including an anatomically accurate left cardiac simulator for training and medical device testing. The system and device uses pneumatically pressurized chambers to generate ventricle and atrium contractions. In conjunction with the interaction of synthetic valves which simulate mitral and aortic valves, the system is designed to generate pumping action that produces accurate volume fractions and pressure gradients of pulsatile flow, duplicating that of a human heart. Through the use of a control unit and sensors, one or more parameters such as flow rates, fluidic pressure, and heart rate may be automatically controlled, using feedback loop mechanisms to adjust parameters of the hydraulic system simulate a wide variety of cardiovascular conditions including normal heart function, severely diseased or injured heart conditions, and compressed vasculature, such as hardening of the arteries.

The present invention provides in vitro methods of expansion and propagation of undifferentiated progenitor cells and more specifically undifferentiated progenitor cells containing Islet1, a marker apparently unique to proliferating cardiac stem cells. Methods are described for isolation of stem cell populations as well as for provoking expansion and propagation of undifferentiated progenitor cells without differentiation, to provide cardiac repair or improve cardiac function, for example.

Heart pacing systems include at least one electronic or biological pacemaker as a primary pacemaker, and at least one electronic or biological pacemaker as a backup pacemaker. When implanted, the primary pacemaker(s) produce primary pacing stimuli that modulate cardiac function. The backup pacemaker(s) provide backup pacing stimuli when the electronic pacemaker is unable to modulate cardiac function at the predetermined pacing rate. The heart pacing systems are implemented by implantation in regions where they can provide pacing stimuli to cardiac tissue.