A cryocatheter system includes a first handle portion having a proximal end, a distal end, a first fluid flow path, and a second fluid flow path; a second handle portion having a proximal end, a distal end, a first fluid flow path, and a second fluid flow path; and a catheter having a proximal end, a distal end, a first fluid flow path, and a second fluid flow path. The distal end of the first handle portion is matable with the proximal end of the second handle portion to place the respective first and second fluid flow paths of each handle portion in fluid communication; and the distal end of the second handle portion is matable with the proximal end of the catheter to place the respective first and second fluid flow paths of the second handle portion and the catheter in fluid communication.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not applicable.

FIELD OF THE INVENTION

This invention relates to catheters, and more particularly to handles and connectors for cryogenic catheters.

BACKGROUND OF THE INVENTION

A cryocatheter can generally be described as an elongate, slender, flexible body that is capable of delivering extreme cold to provide a medically therapeutic effect. Such a catheter can be a part of a system that includes several components, such as a console, an umbilical, a cryoblation catheter and a handle.

The console houses the electronics and software for controlling an ablation procedure. Additionally, the console controls delivery of a refrigerant through the umbilical to the catheter and recovery of the refrigerant from the catheter.

The umbilical connecting the catheter and handle to the console provides mechanical connections for refrigerant transport and electrical connection for electrical devices and sensors. The handle, in addition to providing an appropriate graspable structure, can include controls for catheter steering, as well as other catheter functions.

Known cryocatheter systems provide a unitary handle and catheter which is intended for a single use. As with other devices, attention to the percentage and content of a system that is disposable (or that which must be disposed of for sanitary reasons), as well as attention to the cost of replacement items, can have a substantial effect on the cost of acquisition and operation of the system. Thus, if possible, it would help to reduce cost of the system if only the catheter (or a portion thereof) were disposable and, under most circumstances, the handle were available for reuse.

Ideally, the inclusion of disposable system elements does not compromise system performance or patient safety. However, known attempts to provide disposable catheter elements have been less than ideal. For example, providing a catheter that is removable from the handle requires not only connection to refrigerant, steering elements and electrical elements, but also a creation of a fluid-tight seal at the catheter/handle interface. Not only can it be tedious to make such connections, known devices with this type of feature have not proved to be acceptable with respect to either performance or safety. It would therefore be desirable to provide a cryocatheter and handle that provides the benefits of a disposable component and which is easy to use, without safety or performance limitations.

SUMMARY OF THE INVENTION

The present invention provides a cyrocatheter system having a two-part handle that is easy to connect and use; but the system does not compromise safety and performance requirements.

In an exemplary embodiment, a cryocatheter system includes a first handle portion having a proximal end, a distal end, a first fluid flow path, and a second fluid flow path; a second handle portion having a proximal end, a distal end, a first fluid flow path, and a second fluid flow path; and a catheter having a proximal end, a distal end, a first fluid flow path, and a second fluid flow path. The distal end of the first handle portion is matable with the proximal end of the second handle portion to place the respective first and second fluid flow paths of each handle portion in fluid communication; and the distal end of the second handle portion is matable with the proximal end of the catheter to place the respective first and second fluid flow paths of the second handle portion and the catheter in fluid communication.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1depicts a cryocatheter system in accordance with the invention. The system includes a catheter10, such as those disclosed in U.S. Pat. Nos. 5,899,898 and 5,899,899 to Arless, which are incorporated herein by reference. The system also includes a handle12having a first portion14and a second portion16. First and second umbilicals18and20, respectively, connect the second portion16of the handle12to a console22. The first umbilical18provides a path for a liquid or gas refrigerant to be transferred between the console22and the handle12; and the second umbilical20provides a signal path, such as for electrical signals, between the console22and the handle. Additional umbilicals can be provided as required, and the functions of more than one umbilical can be provided in a single, multifunction umbilical. Further, additional devices, such as a connector box24can be placed in electrical communication with an umbilical. As shown inFIG. 1, the connector box24provides for connection to ECG apparatus (not shown). Also, one or more of the umbilicals can be divisible into two or more portions as shown inFIG. 1, wherein the first umbilical includes portion18and18′, and the second umbilical includes portions20and20′.

Referring now toFIG. 2, additional details of an exemplary two-part handle12are discussed in greater detail. A first handle portion14is shown mated to a cryocatheter10and a second handle portion16is shown mated to a single, multipurpose umbilical26. The first handle portion14defines or includes a portion of a first fluid pathway28and a portion of a second fluid pathway30. The second handle portion16defines or contains a second portion of the first fluid pathway28′ and a second portion of the second fluid pathway30′. When the first and second portions of the first and second fluid pathways are mated, as shown inFIG. 2A, continuous fluid paths are provided. Similarly, the first handle portion14includes a portion of one or more electrical or fiber-optic lines31and the second handle portion16includes a second portion of the one or more electrical or fiber-optic lines31′. Further, the first handle portion14includes a portion of one or more steering elements, such a pull wire33and the second handle portion16includes a second portion of the steering elements33′.

The first and second handle portions, as well as the first and second fluid pathways, one or more electrical or fiber-optic lines, and one or more steering elements are held together by complimentary locking elements32and34as is known in the art, such as locking clips, bayonet, or twist-lock. Similarly, the fluid paths are mated with couplings, the wires with electrical connectors, and the steering elements with mechanical connectors. Thus, in the exemplary embodiment, the catheter10can be disconnected from the umbilical14and discarded, while allowing the first handle portion18, which can include steering mechanisms and other controls, to be retained for further use.

WhereasFIG. 2shows a steering actuator, such as a thumb wheel, for selectively positioning a steering element in the second portion16of the handle12,FIG. 3shows an arrangement where the steering actuator36is located in the first portion14. Additional features visible inFIG. 3include a blood sensor38located and configured in such a manner so as to detect blood being withdrawn from the catheter10through a low pressure or vacuum exhaust line40along with refrigerant injected through a supply tube42. Also shown are electrical controls44in communication with electrical wires46.

In addition to the above features, the refrigerant injection and low pressure or vacuum return lines can be configured coaxially either in an umbilical or in the handle as shown inFIG. 4. In this illustration an umbilical48, a first connector50or handle portion, a second connector52or handle portion, and second umbilical54or catheter are shown. The umbilical48includes an outer tube56and an inner tube58. In the exemplary embodiment, the inner tube58provides a path for fluid (e.g., refrigerant) under positive pressure, whereas the outer tube56provides a path for fluid under reduced or low pressure (e.g., in connection to a vacuum pump55). Thus, if a leak should occur at some point along the inner tube58or its connections to other components, the low pressure environment allows the leak to be contained, thereby preventing refrigerant from escaping the umbilical48. Additional safety is provided by a sensor59in communication with the low-pressure fluid path defined by the outer tube56. The sensor59is tuned to detect a change in pressure within the outer tube56, and when a change is detected, fluid flow into the system is turned off, as a change in pressure can be an indicator that a leak is present in the system.

Continuing to refer toFIG. 4, the umbilical48is mated to the first connector50and the umbilical54is mated to the second connector52. The first connector50includes O-rings60and62and is matable with the second connecter52, as shown in greater detail in the figures that follow, to provide a fluid-tight connection. The first connector50can be locked to the second connector52with the assistance of a bayonet-type connection having complimentary protuberances64and engagement slots66.

FIG. 5is a cross-sectional view of the coaxial connector ofFIG. 4along line5—5. In this view, the first connector50is shown almost fully mated to the second connector52. In this view the inner tube58is shown mated to an inner portion68of the first connector50. The inner portion68defines a fluid path69leading to an outlet70that, when the first and second connectors50and52are mated, aligns with a fluid inlet72to an injection tube74. The O-ring62ensures good sealing of the connection.

Similarly, the outer tube56is shown mated to an outer portion76of the first connector50. The outer portion defines a fluid path78that is in fluid communication with a fluid path80defined by the second connector52. The fluid path80leads to, and is in communication with a fluid path82in the umbilical54. The O-ring60ensures a good seal between the first and second connectors50and52, respectively.

FIG. 6is a cut-away view of the assembly shown inFIG. 6. In this view, the fluid path69, outlet70, fluid inlet72, fluid path78, fluid path80are all clearly visible.

FIG. 7shows an alternative embodiment of a coaxial arrangement. Shown is a first connector84and a second connector86. In this embodiment, a male Leur taper fitting88is receivable within a female Leur taper receptacle90as complimentary locking threads92and94on the first and second connectors are engaged. When the connectors are fully engaged an O-ring seal96prevents leakage for connecting fluid flow paths98and100. Similarly, an O-ring seal102prevents leakage for connecting fluid flow paths104and106. Exemplary fluid flow through flow paths104and106is shown by arrows.

Yet another connector embodiment is shown inFIG. 8. This embodiment provides connections that are not coaxial. As shown, a first connector108is mated to an outer tube or catheter shaft110with a rigid sleeve112and a flexible strain relief element. An fluid injection tube114is connected to a high-pressure female connector fitting116with a flexible connector tube118. Electrical wires120that pass through the outer tube110terminate at a female pin wire connector122. A pull-wire124passes through the outer tube110and a pull-wire seal fitting126to a female pull-wire connector128. A pull-wire tension adjuster130can also be provided.

A second connector132includes a male, high-pressure connector134that is matable with the fitting116to provide a continuous fluid path. A male pull-wire connector136, matable with the connector128, is axially movable within a portion of the second connector132as shown by the double-headed arrow. The connector136is secured to a pull-wire137that is in turn secured to an actuator (such as element36shown inFIGS. 2 and 3). Thus, when the pull-wire137is moved axially, the connector136moves axially. A bias force can be applied by a bias element138, such as a spring, to push the connector136to a selected point when axial tension is reduced on the pull-wire. Also shown is a male wire pin connector140.

A variety of modifications and variations of the present invention are possible in light of the above disclosure. It is therefore understood that, within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described hereinabove.