718 results about "Heart tissues" patented technology

A surgical stapler for securing a prosthetic heart valve within a patient generally includes a first cylindrical portion for carrying at least one staple assembly on a distal end thereof; a second cylindrical portion positioned concentrically about the first cylindrical portion and having a camming arm on a distal end thereof, the camming arm configured to cam the at least one staple assembly radially outward and drive the at least one staple assembly distally such that a first leg of the at least one staple assembly penetrates a cuff of the prosthetic heart valve and a second leg of the at least one staple assembly pierces a portion of heart tissue surrounding the prosthetic heart valve, as the second cylindrical portion is moved distally relative to the first cylindrical portion; and a third cylindrical portion positioned concentrically about the second cylindrical portion and having an anvil flange on a distal end thereof, the anvil flange configured to crimp the second leg of the at least one staple assembly toward the first leg of the at least one staple assembly to secure the prosthetic heart valve to the surrounding heart tissue as the third cylindrical portion is moved relative to the second cylindrical portion. A method of installing a heart valve within a patient which includes the steps of accessing a site within a heart from which a natural heart valve has been removed; lowering a prosthetic heart valve into position within the site in the heart; positioning a surgical stapler having at least one staple assembly removably held on a distal end thereof adjacent the prosthetic heart valve within the site in the heart; driving a first leg of the at least one staple assembly through a peripheral cuff of the prosthetic heart valve; and crimping a second leg of the at least one staple assembly in a direction toward the first leg such that the second leg pierces a portion of heart tissue surrounding the prosthetic heart valve, thereby securing the prosthetic heart valve to the surrounding heart tissue.

Methods and apparatus are provided for selective denervation of conduction pathways in the heart for the treatment of dysrhythmias, including one or more ablation or electroporation catheters having electrodes for stimulating, targeting, and ablating fat pad tissue and other cardiac tissue to selectively denervate heart tissue.

A catheter has a stylet formed of a shape-retentive and resilient material having a preformed curved shape at its distal end resulting in the catheter sheath having the preformed curved shape. The catheter sheath has a plurality of electrodes at its distal end for contacting selected biological tissue for imparting ablation energy thereto. The catheter sheath also has an axially mounted tendon for causing deflection of the distal end. The stylet material permits straightening the catheter sheath during insertion into the patient and advancing the electrodes to the target tissue. Upon removal of the straightening forces, such as by entry into a chamber of the heart, the stylet material resumes its preformed curved distal shape thereby forcing the catheter distal end with the electrodes into the same preformed curved shape. The operator may place the curved distal end into contact with the target tissue and axially move the tendon as desired to gain greater control over the bend in the distal end of the catheter sheath to adjust the radius of curvature of the distal end to obtain greater contact of the electrodes with the heart tissue. Preferably, the stylet is formed of nitinol.

Devices and methods used in termination of a tissue tightening procedure are described. Termination includes the cinching of a tether to tighten the tissue, locking the tether to maintain tension, and cutting excess tether. In procedures involving anchors secured to the tissue, the tether is coupled to the anchors and the tissue is tightened via tension applied to the anchors by cinching the tether. In general, the devices and methods can be used in minimally invasive surgical procedures, and can be applied through small incisions or intravascularly. A method for tightening tissue by fixedly coupling a first anchor to a tether and slidably coupling a second anchor to the tether, securing both anchors to the tissue, applying tension to the tether intravascularly, fixedly coupling the tether to the second anchor, and cutting the tether is described. The tissue to be tightened can comprise heart tissue, in particular heart valve annulus tissue. Various devices and methods for locking the tether in place and cutting excess tether are described.

Tissue shaping methods and devices are provided for reinforcing and/or remodeling heart valves. In certain embodiments, magnetic tissue shaping devices are implanted in tissue adjacent heart valve leaflets. The devices are mutually attractive or repulsive so as to remodel the heart tissue and improve heart valve function. In certain other embodiments, one or more tissue shaping devices including shape memory material are implanted in a patient's body within or on tissue adjacent a heart valve leaflet. The shape memory material can be activated within the patient in a less invasive or non-invasive manner, such as by applying energy percutaneously or external to the patient's body. The shape memory tissue shaping devices are implanted in a first configuration and then activated to remember a second configuration that displaces tissue so as to remodel the heart valve geometry and improve heart valve function. In certain other embodiments, a brace is crimped to the base of a heart valve leaflet to support the leaflet and improve valve closure.

Devices and methods for treating or repairing a heart are disclosed. The device includes at least one anchor configured to engage tissue of a heart and a thread or other elongate member adapted to be coupled to the anchor and secured to heart tissue. The anchor may be attached to papillary muscle tissue and an elongate member may be attached to a valve leaflet for creating artificial chordae tendinae, thereby treating mitral valve prolapse. In another application, multiple anchors may be deployed within a ventricle and the threads pulled together for reducing dilation of a ventricle. A locking mechanism is provided for capturing and locking the threads together, thereby maintaining the ventricle in the reshaped condition.

Implantable medical devices (IMDs) for monitoring signs of acute or chronic cardiac heart failure by measuring cardiac blood pressure and mechanical dimensions of the heart and providing multi-chamber pacing optimized as a function of measured blood pressure and dimensions are disclosed. The dimension sensor or sensors comprise at least a first sonomicrometer piezoelectric crystal mounted to a first lead body implanted into or in relation to one heart chamber that operates as an ultrasound transmitter when a drive signal is applied to it and at least one second sonomicrometer crystal mounted to a second lead body implanted into or in relation to a second heart chamber that operates as an ultrasound receiver. The ultrasound receiver converts impinging ultrasound energy transmitted from the ultrasound transmitter through blood and heart tissue into an electrical signal. The time delay between the generation of the transmitted ultrasound signal and the reception of the ultrasound wave varies as a function of distance between the ultrasound transmitter and receiver which in turn varies with contraction and expansion of a heart chamber between the first and second sonomicrometer crystals. One or more additional sonomicrometer piezoelectric crystal can be mounted to additional lead bodies such that the distances between the three or more sonomicrometer crystals can be determined. In each case, the sonomicrometer crystals are distributed about a heart chamber such that the distance between the separated ultrasound transmitter and receiver crystal pairs changes with contraction and relaxation of the heart chamber walls.

Medical devices, systems, and methods reduce the distance between two points in tissue, often for treatment of congestive heart failure and often in a minimally invasive manner. An anchor is inserted along an insertion path through a first wall of the heart. An arm of the anchor is deployed and rotationally positioned according to a desired alignment. Application of tension to the anchor may draw the first and second walls of the heart into contact along a desired contour so as to effect a desired change in the geometry of the heart. Additional anchors may be inserted and aligned with the first anchor to close off a portion of a ventricle such that the ventricle is geometrically remodeled and disease progression is reversed, halted, and/or slowed.

A cardiac ablation system including an ablation catheter having an anchor adapted to support the ablation catheter within an atrium of a heart and an ultrasound emitter disposed radially outward from a rotation axis and from the anchor, and a control mechanism adapted to rotate the ultrasound emitter about the rotation axis and to provide ablation energy to the ultrasound emitter to ablate heart tissue.

Systems and methods for noninvasive assessment of cardiac tissue properties and cardiac parameters using ultrasound techniques are disclosed. Determinations of myocardial tissue stiffness, tension, strain, strain rate, and the like, may be used to assess myocardial contractility, myocardial ischemia and infarction, ventricular filling and atrial pressures, and diastolic functions. Non-invasive systems in which acoustic techniques, such as ultrasound, are employed to acquire data relating to intrinsic tissue displacements are disclosed. Non-invasive systems in which ultrasound techniques are used to acoustically stimulate or palpate target cardiac tissue, or induce a response at a cardiac tissue site that relates to cardiac tissue properties and/or cardiac parameters are also disclosed.

Devices and methods used in termination of a tissue tightening procedure are described. Termination includes the cinching of a tether to tighten the tissue, locking the tether to maintain tension, and cutting excess tether. In procedures involving anchors secured to the tissue, the tether is coupled to the anchors and the tissue is tightened via tension applied to the anchors by cinching the tether. In general, the devices and methods can be used in minimally invasive surgical procedures, and can be applied through small incisions or intravascularly. A method for tightening tissue by fixedly coupling a first anchor to a tether and slidably coupling a second anchor to the tether, securing both anchors to the tissue, applying tension to the tether intravascularly, fixedly coupling the tether to the second anchor, and cutting the tether is described. The tissue to be tightened can comprise heart tissue, in particular heart valve annulus tissue. Various devices and methods for locking the tether in place and cutting excess tether are described.

A method is provided for ablation in treatment of heart arrhythmias such as atrial fibrillation that includes positioning a catheter apparatus with multiple electrodes within a cardiac chamber, visualizing the catheter apparatus with an interventional system, navigating the catheter apparatus within the cardiac chamber, and delivering energy to selected electrodes of the catheter apparatus from an external source to ablate heart tissue at select locations. Preferably, the external source is an external patch placed on the patient for the delivery of radio-frequency energy. The electrodes of the catheter apparatus are connected to the patch through a patient interface unit where the interface unit selects the electrodes to which radio-frequency energy is to be delivered. In another aspect of the invention, a system for ablation of heart arrhythmias is provided that has a catheter apparatus with multiple electrodes, an interventional system for visualizing the catheter apparatus within a cardiac chamber, and an external source for delivering energy to selected electrodes of the catheter apparatus within the cardiac chamber to ablate heart tissue. Preferably, the system further includes a digital imaging system for obtaining cardiac image data, an image generation system for generating a 3D model of the cardiac chamber from the cardiac image data, and a workstation for registering the 3D model with the interventional system and for visualizing the catheter apparatus over this registered 3D model upon the interventional system.