176 results about "Cardiac assist" patented technology

A cardiac assist device containing a device for connecting the cardiac assist device to a heart, for furnishing electrical impulses from the cardiac assist device to the heart, for ceasing the furnishing of electrical impulses to the heart, for receiving pulsed radio frequency fields, for transmitting and receiving optical signals, and for protecting the heart and the cardiac assist device from currents induced by the pulsed radio frequency fields. The cardiac assist device contains a control circuit comprised of a parallel resonant frequency circuit.

A method for deploying a cardiac-assist device is disclosed. In accordance with the illustrative embodiment, an introducing tube, such as a catheter, sheath, or the like is inserted into the vascular system and advanced beyond the aortic arch. The cardiac-assist device is then inserted into the tube, advanced through it, and deployed from its distal end. In some embodiments, the diameter of the cardiac-assist device expands when it deploys from the distal end of the tube.

One aspect of an intravascular ventricular assist device is an implantable blood pump where the pump includes a housing defining a bore having an axis, one or more rotors disposed within the bore, each rotor including a plurality of magnetic poles, and one or more stators surrounding the bore for providing a magnetic field within the bore to induce rotation of each of the one or more rotors. Another aspect of the invention includes methods of providing cardiac assistance to a mammalian subject as, for example, a human. Further aspects of the invention include rotor bodies having helical channels formed longitudinally along the length of the body of the rotor where each helical channel is formed between peripheral support surface areas facing radially outwardly and extending generally in circumferential directions around the rotational axis of the rotor.

An extracardiac pumping for supplementing the circulation of blood, including the cardiac output, in a patient without any component thereof being connected to the patient's heart, and methods of using same. One embodiment provides a vascular graft that has a first end that is sized and configured to couple to a non-primary blood vessel and a second end that is fluidly coupled to a pump to conduct blood between the pump and the non-primary blood vessel. An outflow conduit is also provided that has a first end sized and configured to be positioned within the same or different blood vessel, whether primary or non-primary, through the vascular graft. The outflow conduit is fluidly coupled to the pump to conduct blood between the pump and the patient. The vascular graft may be connected to the blood vessel subcutaneously to permit application of the extracardiac pumping system in a minimally-invasive procedure.

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.

A temporary cardiac-assist device is disclosed. The device includes a pump assembly that is deployed in the ascending aorta or the heart. A torque transmission line couples the pump assembly to an external motor for driving impeller blades within the pump assembly. The pump assembly expands in size at its destination site for operation. In operation, neither the torque transmission line nor elements that support the impeller blades are under axial forces.

An intravascular extracardiac pumping system for increasing perfusion through a renal artery to tissues of a patient without any component thereof being connected to the patient's heart is provided. The system includes means for pumping blood and a portion that houses the pumping means. The portion that houses the pumping means is configured to direct blood from a location upstream of the pumping means to a location within a renal artery. The pumping means and the portion that houses the pumping means are configured to be insertable into a non-primary vessel subcutaneously in an minimally-invasive procedure for positioning within the patient's vasculature.

An extracardiac pumping for supplementing the circulation of blood, including the cardiac output, in a patient without any component thereof being connected to the patient's heart, and methods of using same. One embodiment of the intravascular extracardiac system comprises a pump with inflow and outflow conduits that are sized and configured to be implantable intravascularly through a non-primary vessel, whereby it may positioned where desired within the patient's vasculature. The system comprises a subcardiac pump that may be driven directly or electromagnetically from within or without the patient. The pump is configured to be operated continuously or in a pulsatile fashion, synchronous with the patient's heart, thereby potentially reducing the afterload of the heart. In another embodiment, the system is positioned extracorporeally, with the inflow conduit and outflow conduit applied percutaneously to a non-primary vessel for circulating blood to and from the non-primary vessel or between the non-primary vessel and another blood vessel within the patient's vasculature.

A method and system measure the instantaneous volume of blood contained within a chamber of a heart, irrespective of its shape, whereby stroke volume and cardiac output volume can be continuously monitored and feedback to a non-blood contacting cardiac assist device. In a preferred form the device uses the distances between the sensors which are implanted in a biomaterial that integrates with a heart surface to determine changes in heart volume. Sonomicrometry crystal measurements are disclosed as a preferred mode of obtaining distance readings. A computer readable medium carries instructions to convert data from dimension sensors into sensor positions within a predetermined coordinate system. Ventricular volume is based on the sensor positions.

The present invention provides a device and method of treating a vessel in a human or animal body.

An apparatus for a heart assist device, comprising a processing unit for computing the blood flow rate from the arterial pressure curve and for predicting at every heartbeat the closing time of the heart valve from the curve of the blood flow rate. The processing unit is adapted to deliver a signal for controlling a heart assist device at a point in time, a period ahead in time of the closing time of the heart valve, wherein the mechanical properties of the said heart assist device are taken into account in determining the period. The apparatus adapts itself to changes in a patient's heart frequency and aortic pressure.

A cardiac assist device synchronization system includes a cardiac assist device and an acoustic or accelerometer sensor that provides a signal input to the cardiac assist device indicative of aortic valve closure. The cardiac assist device is coupled to a mammalian aorta and includes an inflatable chamber and a fluid pump. A fluid conduit is in communication between the chamber and the pump to provide for selective inflation of the chamber. A pump controller triggers the pump in counter-pulsation to a mammalian heart upstream from the aorta. A process for synchronizing a cardiac assist device in counter-pulsation with a left ventricle includes locating an acoustic or accelerometer sensor within a thoracic cavity of a mammal having the assist device coupled to the aorta of the mammal. Through the measurement of an acoustic or acceleration property of an aortic valve of the mammal, and the transmission of aortic valve closure measurement through a controller for the cardiac assist device, counter-pulsatile synchronization for the cardiac assist device is achieved.

A cardiac assist device (100) comprises a stent 103, 403) which is implantable into a blood vessel of a patient. The stent (103, 403) encloses an inner volume (119, 419). At least one inflatable element (104, 409-413) is attached to the stent (103). The at least one inflatable element (104, 409-413) is provided in the inner volume (119, 419) of the stent (103, 403), wherein the ai least one inflatable element (104, 409-413) annularly encloses a central opening (118, 418) being parallel to a longitudinal axis of said stent (103, 403). The cardiac assist device (100) further comprises a fluid supply adapted for periodically inflating and deflating the at least one inflatable element (104, 409-413), wherein said fluid supply comprises at least one fluid supply line (105, 405) connectable to the at least one inflatable element (104, 409-413) and implantable into a blood vessel of the patient.

The present invention is a cardiac-assist device and technique used to maintain a patient's cardiac output when normal cardiac output is insufficient. Blood is removed from a selected ventricle using an arterial or venous side approach. The use of a right side approach reduces the amount of work required and reduces the number of foreign objects present within the left side of the heart and associated blood transferring conduits. The device of the invention includes a flexible catheter positionable within the patient's body. An external assist mechanism connected to one end of the flexible catheter receives blood from the arterial circulation and includes a pumping membrane. A flexible cannula is connected for reinfusing blood. A control console is provided for alternately supplying vacuum and pressure to the pumping membrane. A synchronizing means varies inflation and deflation in synchrony with the cardiac cycle of a patient.

A non-invasive method and apparatus for monitoring of the function of the heart and lungs in vulnerable patients. An analysis of the activity of the heart is made in correspondence to the respiratory system. Using the method of the invention, precise tracking of the changes of the mutual heart-lung interactions cycle are made, enabling better definitions of heart conditions. Within breath variability factor is introduced for tracking heart condition. Failing heart assisting methods and improved diagnostic methods are facilitated using the monitoring system of the invention.

An extracardiac pumping for supplementing the circulation of blood, including the cardiac output, in a patient without any component thereof being connected to the patient's heart, and methods of using same. One embodiment of the intravascular extracardiac system comprises a pump with inflow and outflow conduits that are sized and configured to be implantable intravascularly through a non-primary vessel, whereby it may positioned where desired within the patient's vasculature. The system comprises a subcardiac pump that may be driven directly or electromagnetically from within or without the patient. The pump is configured to be operated continuously or in a pulsatile fashion, synchronous with the patient's heart, thereby potentially reducing the afterload of the heart. In another embodiment, the system is positioned extracorporeally, with the inflow conduit and outflow conduit applied percutaneously to a non-primary vessel for circulating blood to and from the non-primary vessel or between the non-primary vessel and another blood vessel within the patient's vasculature.

A ventricular assist device to provide cardiac assistance to a damaged ventricle chamber. The ventricular assist device is formed of an ventricle body which is anchorable to spaced ventricle wall portions to provide cardiac assistance. Operation of the ventricular assist device is timed or synchronized with the operating phases of the ventricle chamber. The ventricular assist device can be intravascularly deployed to provide a less invasive treatment procedure and can be adapted to provide static support if active assistance is no longer required.

This invention is an improved medical device for non-invasive pulsation, including counterpulsation or simultaneous pulsation, treatment of heart disease and circulatory disorder through external cardiac assistance. The device is a cuff which is affixed on a patient's lower body and extremities, and which constricts or expands by electromechanical activation, thereby augmenting blood pressure for treatment purposes. The cuff contains preferably fixed volume fluids such as gel, air, or water. The cuff envelops and is affixed to the patient's lower body and limbs. In an alternative embodiment, the cuff creates a fixed volume of air between the cuff and the patient such that the cuff creates a vacuum when expanding, thereby stimulating return of blood to the constricted region, permitting better and / or faster responses.

Artificial implantable active and passive girdles include a heart assist system with an artificial myocardium employing a number of flexible, non-distensible tubes with the walls along their long axes connected in series to form a cuff and a passive girdle is wrapped around a heart muscle which has dilatation of a ventricle to conform to the size and shape of the heart and to constrain the dilatation during diastole. The passive girdle is formed of a material and structure that does not expand away from the heart but may, over an extended period of time be decreased in size as dilatation decreases.

Apparatus (20) is provided for compressing at least one ventricle of a heart (40). The apparatus includes a plurality of inflatable elements (64) and a pump (24) in fluid communication with the inflatable elements. At least one band (68) is in mechanical communication with the inflatable elements. A portion of the band is adapted to be placed around at least a portion of the heart in mechanical communication with the portion of the heart. The inflatable elements are arranged such that when the inflatable elements are inflated by the pump, the inflatable elements apply more force to the heart via shortening of the portion of the band than via expansion of the inflatable elements against the heart.

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 heart assist device comprising a rotary pump housing having a cylindrical bore, a pumping chamber and a motor stator including an electrically conductive coil located within the housing and surrounding a portion of the cylindrical bore. A rotor has a cylindrical shaft, at least one impeller appended to one end of the shaft, and a plurality of magnets located within the shaft. The rotor shaft is positioned within the housing bore with the magnets opposite the motor stator, and the impeller is positioned within the pumping chamber. The housing bore is closely fitted to the outer surface of the shaft forming a hydrodynamic journal bearing, with the pumping chamber and journal bearing connected by a leak path of blood flow between the pumping chamber and the journal bearing. A backiron of the motor stator attracts the rotor magnets to resist longitudinal displacement of the rotor within the housing during operation. The relative orientation of positions of the inflow, outflow, and leakage flow paths may be varied within the pump, such as to accommodate different intended methods for implantation and / or use.

The present invention relates to providing counter-pulsation heart assist by deforming the aorta. In a preferred embodiment, the deformation pressure is applied by cyclically, preferably in synchrony with the diastolic period of the heart. The deformation pressure may be applied to the outer wall of the aorta or to a patch covering a resected opening in the wall of the aorta.

A ventricular assist device comprising a housing defining an interior space, at least two ports opening into said interior space, and at least one pump for pumping blood between the ports through said interior space, the ports and interior space providing a continuous blood flow path that is not interrupted by valves.