Abstract: In a system for retrieving an implanted device, a flared inner surface of a catheter tubular sidewall may define a distal-most opening of a device receptacle; the opening has a first diameter equal to that of the receptacle, and a second diameter, coincident with a distal-most edge of the tubular sidewall, and at least 5% greater than the receptacle diameter. Alternately, a retrieval tool in sliding engagement within a lumen of a catheter includes a shaft assembly, through which a snare member passes, and which includes a collapsible spring-biased perimeter sidewall; the sidewall defines a capture member passageway approximately coaxial, and in fluid communication with a lumen of the shaft assembly. A distal-most opening of the passageway has a spring-biased diameter that is greater than that of a distal-most opening of a device receptacle of the catheter, and a collapsed diameter that is less than the receptacle distal-most opening diameter.

Abstract: A shaft of an interventional medical system catheter has a distal end formed by opposing elastically deformable retention features that protrude into a lumen of the shaft, and that define an expandable distal opening of the lumen. The retention features secure an implantable medical device to the catheter by an interlocking engagement within a gap defined by a necked-in portion of a device holding member. Each retention feature includes a distal-facing surface defining the distal opening, and, when an elongate release member of the catheter, which extends within the shaft lumen, applies a push force against proximal-facing surfaces of the features, the distal opening expands from a constricted to an open configuration, wherein the open configuration allows passage of the device holding member through the distal opening, and the constricted configuration allows for the interlocking engagement with the device.

Abstract: An engagement subassembly of a catheter, for retrieving an implanted medical device, may include at least three segments or, alternately, capture members being spring biased outward from a longitudinal axis of the subassembly, wherein a device receptacle of the catheter forces the capture members/segments, against the spring bias thereof, toward the axis. Each capture member includes a spring-biased wire and a grip, which is located between proximal and distal portions of the corresponding wire, and which is configured to interlock within a gap between a device attachment feature and housing; a length of each wire distal portion may be approximately equal to that of the device housing. An interlocking edge of each segment interlocks within the gap between the attachment feature and housing, when a distal-facing surface of each segment, which tapers outward from the axis in a distal direction, comes into confronting engagement with the device housing.

Abstract: A shaft of an interventional medical system catheter has a distal end formed by opposing elastically deformable retention features that protrude into a lumen of the shaft, and that define an expandable distal opening of the lumen. The retention features secure an implantable medical device to the catheter by an interlocking engagement within a gap defined by a necked-in portion of a device holding member. Each retention feature includes a distal-facing surface defining the distal opening, and, when an elongate release member of the catheter, which extends within the shaft lumen, applies a push force against proximal-facing surfaces of the features, the distal opening expands from a constricted to an open configuration, wherein the open configuration allows passage of the device holding member through the distal opening, and the constricted configuration allows for the interlocking engagement with the device.

Abstract: An engagement subassembly of a catheter, for retrieving an implanted medical device, may include at least three segments or, alternately, capture members being spring biased outward from a longitudinal axis of the subassembly, wherein a device receptacle of the catheter forces the capture members/segments, against the spring bias thereof, toward the axis. Each capture member includes a spring-biased wire and a grip, which is located between proximal and distal portions of the corresponding wire, and which is configured to interlock within a gap between a device attachment feature and housing; a length of each wire distal portion may be approximately equal to that of the device housing. An interlocking edge of each segment interlocks within the gap between the attachment feature and housing, when a distal-facing surface of each segment, which tapers outward from the axis in a distal direction, comes into confronting engagement with the device housing.

Abstract: In a system for retrieving an implanted device, a flared inner surface of a catheter tubular sidewall may define a distal-most opening of a device receptacle; the opening has a first diameter equal to that of the receptacle, and a second diameter, coincident with a distal-most edge of the tubular sidewall, and at least 5% greater than the receptacle diameter. Alternately, a retrieval tool in sliding engagement within a lumen of a catheter includes a shaft assembly, through which a snare member passes, and which includes a collapsible spring-biased perimeter sidewall; the sidewall defines a capture member passageway approximately coaxial, and in fluid communication with a lumen of the shaft assembly. A distal-most opening of the passageway has a spring-biased diameter that is greater than that of a distal-most opening of a device receptacle of the catheter, and a collapsed diameter that is less than the receptacle distal-most opening diameter.

Abstract: An interventional medical system includes an elongate shaft, a steering assembly coupled to the shaft, a snare member, and a passageway configured to allow passage of the snare member therethrough and into a first longitudinally extending lumen of the shaft; wherein the passageway is spaced distally from the steering assembly actuator by no more than 3 cm to 3.5 cm, and the passageway includes an elastic sealing perimeter. The passageway may, in some cases, be formed in a tapered member of the steering assembly that couples a proximal end of the shaft to a core of the steering assembly.