331 results about "Right ventricles" patented technology

A leadless intra-cardiac medical device senses cardiac activity from multiple chambers and applies cardiac stimulation to at least one cardiac chamber and / or generates a cardiac diagnostic indication. The leadless device may be implanted in a local cardiac chamber (e.g., the right ventricle) and detect near-field signals from that chamber as well as far-field signals from an adjacent chamber (e.g., the right atrium).

Apparatus is provided including an implantable sensor, adapted to sense an electrical parameter of a heart of a subject, and a first control unit, adapted to apply pulses to the heart responsively to the sensed parameter, the pulses selected from the list consisting of: pacing pulses and anti-arrhythmic energy. The apparatus further includes an electrode device, adapted to be coupled to a site of the subject selected from the list consisting of: a vagus nerve of the subject, an epicardial fat pad of the subject, a pulmonary vein of the subject, a carotid artery of the subject, a carotid sinus of the subject, a coronary sinus of the subject, a vena cava vein of the subject, a right ventricle of the subject, and a jugular vein of the subject; and a second control unit, adapted to drive the electrode device to apply to the site a current that increases parasympathetic tone of the subject and affects a heart rate of the subject. The first and second control units are not under common control. At least one of the control units is adapted to coordinate an aspect of its operation with an aspect of operation of the other control unit. Other embodiments are also described.

A heart pacemaker which is arranged to stimulate the apical area of the heart. Stimulation of this area provides synchronous mechanical contraction of the left and right ventricles and overcomes the problem of pacemaker induced left bundle branch block type conduction disturbance. The pacemaker has a base surface which conforms to the apical area of the heart and mounts a plurality of epicardial stimulating electrodes. Selection of electrodes can be made to provide the most clinically appropriate stimulation. An opposite side of the pacemaker is arranged to contact the diaphragm and is provided with sensing electrodes to sense activity of the diaphragm and adjust pacing of the heart in accordance with changes in physical activity of the patient. The electrodes used are preferably of capacitive construction, having first and second capacitive plates either side of a dielectric formed by the body of the pacemaker.

A treatment method is provided, including identifying a subject as one who is selected to undergo an interventional medical procedure, and, in response to the identifying, reducing a likelihood of a potential adverse effect of the procedure by applying an electrical current to a parasympathetic site of the subject selected from the group consisting of: a vagus nerve of the subject, an epicardial fat pad of the subject, a pulmonary vein of the subject, a carotid artery of the subject, a carotid sinus of the subject, a coronary sinus of the subject, a vena cava vein of the subject, a jugular vein of the subject, a right ventricle of the subject, a parasympathetic ganglion of the subject, and a parasympathetic nerve of the subject.

Apparatus is provided including an electrode device and a control unit. The electrode device is configured to be coupled to a site of a subject selected from the group consisting of: a vagus nerve, an epicardial fat pad, a pulmonary vein, a carotid artery, a carotid sinus, a coronary sinus, a vena cava vein, a right ventricle, a right atrium, and a jugular vein. The control unit is configured to drive the electrode device to apply to the site a current in at least first and second bursts, the first burst including a plurality of pulses, and the second burst including at least one pulse, and set (a) a pulse repetition interval (PRI) of the first burst to be on average at least 20 ms, (b) an interburst interval between initiation of the first burst and initiation of the second burst to be less than 10 seconds, (c) an interburst gap between a conclusion of the first burst and the initiation of the second burst to have a duration greater than the average PRI, and (d) a burst duration of the first burst to be less than a percentage of the interburst interval between, the percentage being less than 67%. Other embodiments are also described.

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.

A method of treating hemodynamic disfunction by simultaneously pacing both ventricles of a heart. At least one ECG amplifier is arranged to separately detect contraction of each ventricle and a stimulator is then activated for issuing stimulating pulses to both ventricles in a manner to assure simultaneous contraction of both ventricles, thereby to assure hemodynamic efficiency. A first ventricle is stimulated simultaneously with contraction of a second ventricle when the first fails to properly contract. Further, both ventricles are stimulated after lapse of a predetermined A-V escape interval. One of a pair of electrodes, connected in series, is placed through the superior vena cava into the right ventricle and a second is placed in the coronary sinus about the left ventricle. Each electrode performs both pacing and sensing functions. The pacer is particularly suitable for treating bundle branch blocks or slow conduction in a portion of the ventricles.

A system for manipulating and supporting a beating heart during cardiac surgery, including a gross support element for engaging and supporting the heart (the gross support element preferably including a head which is sized and shaped to cradle the myocardium of the left ventricle), a suspension head configured to exert lifting force on the heart when positioned near the apical region of the heart at a position at least partially overlying the right ventricle, and a releasable attachment element for releasably attaching at least one of the gross support element and the suspension head to the heart. The releasable attachment element can be a mechanical element (such as one or more staples or sutures) or an adhesive such as glue. Alternatively, the system includes a suspension head and a releasable attachment element for releasably attaching it to the heart, but does not include a gross support element.

The present invention provides a method and apparatus for assessing ventricular function on a chronic basis using a plurality of electrodes disposed on or about a left ventricle and / or a right ventricle—and optionally, at least one mechanical or metabolic sensor—all operatively electrically coupled to an implantable medical device. The plurality of electrodes are preferably spaced-apart so that at least one electrode is disposed electrical communication with a discrete volume of ventricular tissue. In one embodiment, the discrete volume of tissue is defined by multiple longitudinal and axial planes as known and used in the medical arts. Thus, according to the present invention, at least one electrode couples to appropriate sensing circuitry and essentially provides a localized electrogram (EGM) that, when compared to other EGMs, provides for configurable, localized delivery of therapeutic pacing stimulus, diverse impedance-sensing vectors, various diagnostic information regarding myocardial function and / or anti-tachycardia pacing.

Apparatus and methods are provided for delivering a lead over a rail into a target body lumen, cavity, or other vessel, e.g., a coronary vein or a right ventricle within a patient's heart. For example, a distal end of an elongate guidewire or other rail may be introduced into the coronary venous system via the coronary sinus, advanced through the coronary venous system to a location beyond a target vessel, and secured at the location beyond the target vessel. A catheter or other elongate tubular member is advanced over the rail and manipulated to position an outlet of the tubular member adjacent to or otherwise aligned relative to the target vessel. A distal end of a lead is delivered through the tubular member and out the outlet into the target vessel. The catheter and rail are then removed, leaving the lead within the target vessel.

The invention includes a method of locating a tip of a central venous catheter (“CVC”) having a distal and proximal pair of electrodes disposed within the superior vena cava, right atrium, and / or right ventricle. The method includes obtaining a distal and proximal electrical signal from the distal and proximal pair and using those signals to generate a distal and proximal P wave, respectively. A deflection value is determined for each of the P waves. A ratio of the deflection values is then used to determine a location of the tip of the CVC. Optionally, the CVC may include a reference pair of electrodes disposed within the superior vena cava from which a reference deflection value may be obtained. A ratio of one of the other deflection values to the reference deflection value may be used to determine the location of the tip of the CVC.

An endocardial apparatus for pacing four chambers of a heart, comprising: a power source housed in an implantable can, first, second and third leads having proximal and distal ends, each lead being electrically connected to the power source at its proximal end and extending into a vein proximal the heart, the first lead connecting at its distal end to an electrode that is in electrical contact with the right atrium of the heart, the second lead connecting at its distal end to an electrode that is in electrical contact with the right ventricle of the heart, the third lead connecting at a point proximal its distal end to a first electrode that is in electrical contact with the inside of the coronary sinus and oriented so as to stimulate the left atrium of the heart and connecting at its distal end to a second electrode that is in electrical contact with the inside of the great cardiac vein and oriented so as to stimulate the left ventricle of the heart. Devices are also disclosed for orienting and maintaining the position of the electrodes on the third lead.

Methods and systems for closing an opening or defect in tissue, closing a lumen or tubular structure, cinching or remodeling a cavity or repairing a valve preferably utilizing a purse string or elastic device. The preferred devices and methods are directed toward catheter-based percutaneous, transvascular techniques used to facilitate placement of the devices within lumens, such as blood vessels, or on or within the heart to perform structural defect repair, such as valvular or ventricular remodeling. In some methods, the catheter is positioned within the right ventricle, wherein the myocardial wall or left ventricle may be accessed through the septal wall to position a device configured to permit reshaping of the ventricle. The device may include a line or a plurality of anchors interconnected by a line. In one arrangement, the line is a coiled member.

A tiny electrically powered hydrodynamic blood pump is disclosed which occupies one third of the aortic or pulmonary valve position, and pumps directly from the left ventricle to the aorta or from the right ventricle to the pulmonary artery. The device is configured to exactly match or approximate the space of one leaflet and sinus of valsalva, with part of the device supported in the outflow tract of the ventricular cavity adjacent to the valve. In the configuration used, two leaflets of the natural tri-leaflet valve remain functional and the pump resides where the third leaflet had been. When implanted, the outer surface of the device includes two faces against which the two valve leaflets seal when closed. To obtain the best valve function, the shape of these faces may be custom fabricated to match the individual patient's valve geometry based on high resolution three dimensional CT or MRI images. Another embodiment of the invention discloses a combined two leaflet tissue valve with the miniature blood pump supported in the position usually occupied by the third leaflet. Either stented or un-stented tissue valves may be used. This structure preserves two thirds of the valve annulus area for ejection of blood by the natural ventricle, with excellent washing of the aortic root and interface of the blood pump to the heart. In the aortic position, the blood pump is positioned in the non-coronary cusp. A major advantage of the transvalvular VAD is the elimination of both the inflow and outflow cannulae usually required with heart assist devices.

The present invention relates to devices and methods for improving the function of a defective heart valve, and particularly for reducing regurgitation through an atrioventricular heart valve—i.e., the mitral valve and the tricuspid valve. For a tricuspid repair, the device includes an anchor deployed in the tissue of the right ventricle, in an orifice opening to the right atrium, or anchored to the tricuspid valve. A flexible anchor rail connects to the anchor and a coaptation element on a catheter rides over the anchor rail. The catheter attaches to the proximal end of the coaptation element, and a locking mechanism fixes the position of the coaptation element relative to the anchor rail. Finally, there is a proximal anchoring feature to fix the proximal end of the coaptation catheter subcutaneously adjacent the subclavian vein. The coaptation element includes an inert covering and helps reduce regurgitation through contact with the valve leaflets.

Methods of locating a tip of a central venous catheter (“CVC”) relative to the superior vena cava, sino-atrial node, right atrium, and / or right ventricle using electrocardiogram data. The CVC includes at least one electrode. In particular embodiments, the CVC includes two or three pairs of electrodes. Further, depending upon the embodiment implemented, one or more electrodes may be attached to the patient's skin. The voltage across the electrodes is used to generate a P wave. A reference deflection value is determined for the P wave detected when the tip is within the proximal superior vena cava. Then, the tip is advanced and a new deflection value determined. A ratio of the new and reference deflection values is used to determine a tip location. The ratio may be used to instruct a user to advance or withdraw the tip.

A method and apparatus are disclosed for treating a condition of a patient's heart includes placing a first electrode and a second electrode in a right ventricle of the heart. A reference electrode is placed within the patient and internal or external to the heart. A pacing signal is generated including a first signal component, a second signal component and a reference component with the first and second signal components having opposite polarity and with both of the first and second components having a potential relative to the reference component. The first component is transmitted to the first electrode. The second component is transmitted to the second electrode. The reference electrode is connected to the reference component which may be an electrical ground. The pacing signal and the placement of the electrodes are selected to alter a contraction of a left ventricle of the heart.

A method and system for generating a patient specific anatomical heart model is disclosed. Volumetric image data, such as computed tomography (CT) or echocardiography image data, of a patient's cardiac region is received. Individual models for multiple heart components, such as the left ventricle (LV) endocardium, LV epicardium, right ventricle (RV), left atrium (LA), right atrium (RA), mitral valve, aortic valve, aorta, and pulmonary trunk, are estimated in said volumetric cardiac image data. A patient specific anatomical heart model is generated by integrating the individual models for each of the heart components.

A method and system for building a statistical four-chamber heart model from 3D volumes is disclosed. In order to generate the four-chamber heart model, each chamber is modeled using an open mesh, with holes at the valves. Based on the image data in one or more 3D volumes, meshes are generated and edited for the left ventricle (LV), left atrium (LA), right ventricle (RV), and right atrium (RA). Resampling to enforce point correspondence is performed during mesh editing. Important anatomic landmarks in the heart are explicitly represented in the four-chamber heart model of the present invention.

A heart pacemaker which is arranged to stimulate the apical area of the heart. Stimulation of this area provides synchronous mechanical contraction of the left and right ventricles and overcomes the problem of pacemaker induced left bundle branch block type conduction disturbance. The pacemaker has a base surface which conforms to the apical area of the heart and mounts a plurality of epicardial stimulating electrodes. Selection of electrodes can be made to provide the most clinically appropriate stimulation. An opposite side of the pacemaker is arranged to contact the diaphragm and is proved with sensing electrodes to sense activity of the diaphragm and adjust pacing of the heart in accordance with changes in physical activity of the patient. The electrodes used are preferably of capacitive construction, having first and second capacitive plates either side of a dielectric formed by he body of the pacemaker.

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.

Apparatus is provided including an electrode device and a control unit. The electrode device is configured to be coupled to a site of a subject selected from the group consisting of: a vagus nerve, an epicardial fat pad, a pulmonary vein, a carotid artery, a carotid sinus, a coronary sinus, a vena cava vein, a right ventricle, a right atrium, and a jugular vein. The control unit is configured to drive the electrode device to apply to the site a current in at least first and second bursts, the first burst including a plurality of pulses, and the second burst including at least one pulse, and set (a) a pulse repetition interval (PRI) of the first burst to be on average at least 20 ms, (b) an interburst interval between initiation of the first burst and initiation of the second burst to be less than 10 seconds, (c) an interburst gap between a conclusion of the first burst and the initiation of the second burst to have a duration greater than the average PRI, and (d) a burst duration of the first burst to be less than a percentage of the interburst interval between, the percentage being less than 67%. Other embodiments are also described.

Method and system for computation of advanced heart measurements from medical images and data; and therapy planning using a patient-specific multi-physics fluid-solid heart model is disclosed. A patient-specific anatomical model of the left and right ventricles is generated from medical image patient data. A patient-specific computational heart model is generated based on the patient-specific anatomical model of the left and right ventricles and patient-specific clinical data. The computational model includes biomechanics, electrophysiology and hemodynamics. To generate the patient-specific computational heart model, initial patient-specific parameters of an electrophysiology model, initial patient-specific parameters of a biomechanics model, and initial patient-specific computational fluid dynamics (CFD) boundary conditions are marginally estimated. A coupled fluid-structure interaction (FSI) simulation is performed using the initial patient-specific parameters, and the initial patient-specific parameters are refined based on the coupled FSI simulation. The estimated model parameters then constitute new advanced measurements that can be used for decision making.

The present invention relates to devices and methods for improving the function of a defective heart valve, and particularly for reducing regurgitation through an atrioventricular heart valve—i.e., the mitral valve and the tricuspid valve. For a tricuspid repair, the device includes an anchor deployed in the tissue of the right ventricle, in an orifice opening to the right atrium, or anchored to the tricuspid valve. A flexible anchor rail connects to the anchor and a coaptation element on a catheter rides over the anchor rail. The catheter attaches to the proximal end of the coaptation element, and a locking mechanism fixes the position of the coaptation element relative to the anchor rail. Finally, there is a proximal anchoring feature to fix the proximal end of the coaptation catheter subcutaneously adjacent the subclavian vein. The coaptation element includes an inert covering and helps reduce regurgitation through contact with the valve leaflets.

A method and system for patient-specific planning of cardiac therapy, such as cardiac resynchronization therapy (CRT), based on preoperative clinical data and medical images, such as ECG data, magnetic resonance imaging (MRI) data, and ultrasound data, is disclosed. A patient-specific anatomical model of the left and right ventricles is generated from medical image data of a patient. A patient-specific computational heart model, which comprises cardiac electrophysiology, biomechanics and hemodynamics, is generated based on the patient-specific anatomical model of the left and right ventricles and clinical data. Simulations of cardiac therapies, such as CRT at one or more anatomical locations are performed using the patient-specific computational heart model. Changes in clinical cardiac parameters are then computed from the patient-specific model, constituting predictors of therapy outcome useful for therapy planning and optimization.

Methods and devices for determining optimal Atrial to Ventricular (AV) pacing intervals and Ventricular to Ventricular (VV) delay intervals in order to optimize cardiac output. Impedance, preferably sub-threshold impedance, is measured across the heart at selected cardiac cycle times as a measure of chamber expansion or contraction. One embodiment measures impedance over a long AV interval to obtain the minimum impedance, indicative of maximum ventricular expansion, in order to set the AV interval. Another embodiment measures impedance change over a cycle and varies the AV pace interval in a binary search to converge on the AV interval causing maximum impedance change indicative of maximum ventricular output. Another method varies the right ventricle to left ventricle (VV) interval to converge on an impedance maximum indicative of minimum cardiac volume at end systole. Another embodiment varies the VV interval to maximize impedance change.