Patent Description:
Diseased or otherwise deficient heart valves can be repaired or replaced with an implanted prosthetic heart valve. Conventionally, heart valve replacement surgery is an open-heart procedure conducted under general anesthesia, during which the heart is stopped and blood flow is controlled by a heart-lung bypass machine. Traditional open surgery inflicts significant patient trauma and discomfort, and exposes the patient to a number of potential risks, such as infection, stroke, renal failure, and adverse effects associated with the use of the heart-lung bypass machine, for example.

Due to the drawbacks of open-heart surgical procedures, there has been an increased interest in minimally invasive and percutaneous replacement of cardiac valves. With percutaneous transcatheter (or transluminal) techniques, a valve prosthesis is compacted for delivery in a catheter and then advanced, for example, through an opening in the femoral artery and through the descending aorta to the heart, where the prosthesis is then deployed in the annulus of the valve to be restored (e.g., the aortic valve annulus). Although transcatheter techniques have attained widespread acceptance with respect to the delivery of conventional stents to restore vessel patency, only mixed results have been realized with percutaneous delivery of the more complex prosthetic heart valve.

A delivery catheter must often navigate through tortuous anatomy as it is tracked through the vasculature to the treatment site within the heart. The catheter may be navigated through various anatomical turns as it travels within the vasculature, including the sharp bend of the aortic arch.

<CIT> describes a rotate-to-advance catheterization system.

<CIT> describes a bifurcation stent delivery catheter and method.

<CIT> describes a heart valve prosthesis delivery system and method for delivery of heart valve prosthesis with introducer sheath and loading system.

The present disclosure addresses problems and limitations associated with the related art.

The techniques of this disclosure generally relate to a catheter for use in delivering a prosthesis via percutaneous transcatheter (or transluminal) techniques. It is desirable that the clinician have the ability to accurately steer or deflect the catheter as it is guided and advanced to the treatment site. Embodiments of the disclosure achieve deflection of a delivery catheter as it navigates the anatomy of the vasculature while advancing to a desired treatment site.

In one aspect, the present disclosure provides a catheter including a plurality of a segments, each segment having a stiffener extending along its length. The plurality of segments are interconnected with connectors such that each of the segments can bend in multiple planes via rotation of the connectors.

According to the invention, the disclosure provides a catheter for delivering a prosthesis including a first tubular segment having a distal end and a proximal end; the first tubular segment further having a body and a set of spine wires longitudinally arranged with respect to the body. The catheter further includes a second tubular segment having a distal end and a proximal end; the second tubular segment further having a body and a set of spine wires longitudinally arranged with respect to the body. The catheter also includes a first connector having a first portion connected to the distal end of the first tubular segment and a second portion connected to the proximal end of the second tubular segment; wherein the first portion and the second portion are engaged so that the first and second portions can rotate with respect to each other.

<FIG> collectively illustrate a catheter <NUM> including a plurality of tubular segments <NUM>, <NUM>, <NUM> interconnected by connectors or torque relief nodes <NUM>. The catheter <NUM> can be of the type for delivering a prosthesis (not shown) via percutaneous transcatheter (or transluminal) techniques. In such embodiments, at a proximal end 22a, the catheter <NUM> can include a handle assembly <NUM>. At a distal end 22b, the catheter <NUM> can include a capsule <NUM> for compressively containing the prosthesis positioned therein. During such transcatheter techniques, it is typical for the catheter <NUM> to navigate through a series of bend in different planes and to deploy and recapture a prosthesis often requires a catheter that is sufficiently stiff with respect to tension and compression while maintaining a low bending stiffness, which is uniform around its circumference. Embodiments of the disclosure provide the required stiffness in tension and compression while also providing bending of the catheter in multiple planes. This bending function results in increased ability for the catheter to track through tortuous anatomies with bends in multiple planes and a reduced track force (i.e. reduced trauma to the patient).

In one example, the catheter <NUM> includes a first tubular segment <NUM> having a proximal end <NUM> and a distal end <NUM>. The first tubular segment <NUM> further has a body <NUM> and a set of stiffeners <NUM> (e.g., spine wires) longitudinally arranged with respect to the body <NUM>. Only one stiffener <NUM> is visible in <FIG>, however, additional stiffeners can be positioned around the body <NUM>, as desired. The catheter <NUM> also includes a second tubular segment <NUM> having a proximal end <NUM> and a distal end <NUM>. The second tubular segment <NUM> further has a body <NUM> and a set of spine wires <NUM> longitudinally arranged with respect to the body <NUM> (only one spine wire <NUM> is visible as with segment <NUM>). In the illustrated example, the catheter <NUM> optionally further includes a third tubular segment <NUM> having a proximal end <NUM> and a distal end <NUM>. The third tubular segment <NUM> further has a body <NUM> and a set of spine wires <NUM> longitudinally arranged with respect to the body <NUM> (only one spine wire <NUM> is visible as with segment <NUM>). All segments <NUM>, <NUM>, <NUM> can optionally be identically configured or can vary in configuration. In some embodiments, the catheter <NUM> includes additional tubular segments (e.g., between <NUM>-<NUM> segments), as desired, and the present disclosure is not intended to be limited to a particular number of tubular segments.

As previously indicated, one or more of the tubular segments <NUM>, <NUM>, <NUM> includes two spine wires <NUM>, <NUM>, <NUM> extending along a length of the respective tubular segment <NUM>, <NUM>, <NUM>. In one example, each spine wire <NUM>, <NUM>, <NUM> extends and entire length of the respective tubular segment <NUM>, <NUM>, <NUM>. The spine wires <NUM>, <NUM>, <NUM> are coaxial with a center axis of the respective tubular segment <NUM>, <NUM>, <NUM> and can be embedded within the respective body <NUM>, <NUM>, <NUM> of the respective tubular segment <NUM>, <NUM>, <NUM> or otherwise attached to the respective body <NUM>, <NUM>, <NUM>. The spine wires <NUM>, <NUM>, <NUM> have a stiffness greater than a stiffness of the body <NUM>, <NUM>, <NUM> to support the body to resist compression, while allowing the body to bend. In one example, the spine wires <NUM>, <NUM>, <NUM> of a particular tubular segment <NUM>, <NUM>, <NUM> are positioned about <NUM> degrees (+/- <NUM> degrees) about a circumference of the body <NUM>, <NUM>, <NUM>.

To provide bending of the catheter <NUM> in multiple planes, two tubular segments <NUM>, <NUM>, <NUM> are interconnected with one connector <NUM> interconnecting two respective tubular segments. In the example of <FIG>, the first and second tubular segments <NUM>, <NUM> are interconnected with one connector <NUM> and the second and third tubular segments <NUM>, <NUM> are interconnected with a second connector <NUM>. As indicated with like reference numerals, it is to be understood that each connector <NUM> provided in the catheter <NUM> can be identically configured. In some embodiments, the connectors <NUM> provided can vary with respect to each other in ways described herein, for example. Each connector <NUM> includes a first portion <NUM> and a second portion <NUM>. In on example, the first portion <NUM> is connected to the distal end <NUM> of the first tubular segment <NUM> and the second portion <NUM> is connected to the proximal end <NUM> of the second tubular segment <NUM>. The first portion <NUM> and the second portion <NUM> are engaged so that the first and second portions <NUM>, <NUM> can rotate about their joint central axis A with respect to each other. In one example, the first and second portions <NUM>, <NUM> can rotated <NUM> degrees with respect to each other. In this way, the tubular segments <NUM>, <NUM> of the catheter <NUM> can rotate relative to each other to navigate tortuous anatomy. It will be understood that the distal/proximal order of the first and second portions <NUM>, <NUM> can be reversed as shown in <FIG>, for example.

One example of suitable connector <NUM> is shown in greater detail in <FIG>. The first portion <NUM> includes a first end 70a having a plurality of collet segments <NUM> (two of which are referenced for ease of illustration). The first portion <NUM> is shown as having four collet segments <NUM>, however, more or fewer collet segments are envisioned. The collect segments <NUM> are connected to a mid portion <NUM>. A second end 70b of the first portion <NUM> is configured to support and receive one end of one tubular segment and can optionally have a beveled surface. The mid portion <NUM> can have a larger outer diameter as compared to an outer diameter of the second end 70b for the end of the respective tubular segment to abut against. In one example, the first portion <NUM> further includes a central aperture <NUM> extending from the first end 70a to the second end 70b.

The second portion <NUM> includes a first end 80a having a receiving aperture <NUM> in which the collect segments <NUM> can be inserted and rotatingly retained therein via a ridge <NUM>. In one example, the collet segments each include a ramped surface <NUM>. Each of the collect segments <NUM> can be compressed toward axis A to slide past ridge <NUM>. Once in receiving aperture <NUM>, the collect segments <NUM> snap back away from axis A (see, in particular, <FIG>). In one example, the first end 80a of the second portion <NUM> abuts against the mid portion <NUM> when the first and second portions <NUM>, <NUM> are engaged. A second end 80b of the second portion <NUM> is configured to support and receive one end of one tubular segment and can optionally have a beveled surface. In one example, the second portion <NUM> includes a central aperture <NUM> extending from the first end 80a to the second end 80b and in communication with the receiving aperture <NUM>. In one example, the central aperture <NUM> has a diameter equal that the central aperture <NUM>. The connector <NUM> is provided merely as one example and other connectors suitable for connecting two tubular segments and allowing rotation of the tubular segments about each other are also considered within the scope of the present disclosure.

Referring now in addition to <FIG>, which illustrates a portion of an alternative catheter <NUM> that includes a first multi-filar coil <NUM> secured to the first tubular segment <NUM> adjacent to and connected to the second portion <NUM> of the connector <NUM> and a second multi-filar coil <NUM> secured to the second tubular segment <NUM> adjacent to and connected to the first portion <NUM> of the connector <NUM>. The multi-filar coils <NUM> create a section of increased flexibility to minimize the stress concentrated at these locations of the catheter <NUM>. As at least partially indicated with like reference numerals, the catheter <NUM> of <FIG> is otherwise identical to and operates similar to catheter <NUM> disclosed above unless explicitly stated.

Similarly, <FIG> illustrates a portion of an alternative catheter <NUM> that includes a first jacket 290a secured to the first tubular segment <NUM> adjacent to the first portion of the connector <NUM> and a second jacket 290b secured to the second tubular segment <NUM> adjacent to the first portion <NUM> of the connector <NUM>. Each jacket 290a, 290b creates a section of increased stiffness/durometer to minimize the stress concentrated at the location of the respective jacket. In one example, one or more the jackets 290a, 290b has a variable stiffness/durometer. For example, the stiffness of each jacket 290a, 290b may increase in the direction of the connector <NUM>. As at least partially indicated with like reference numerals, the catheter <NUM> of <FIG> is otherwise identical to and operates similar to catheter <NUM> unless explicitly stated.

In one example, a catheter was tested using a compound bend box having three <NUM> degree bends in different planes. A catheter having two spine wires but not including any connectors disclosed herein got stuck after the first bend due to the spine wires limiting the catheter to one plane of bending. In a second test, a catheter including a connector herein allowed the tubular segments of the catheter rotate in different planes, which enabled the catheter to go through the second bend before getting stuck in the compound bend box. The tested catheter of the disclosure traveled approximately <NUM> further through the compound bend box.

Claim 1:
A catheter (<NUM>) for delivering a prosthesis, comprising:
a first tubular segment (<NUM>) having a distal end (<NUM>) and a proximal end (<NUM>); the first tubular segment further having a body (<NUM>) and a set of spine wires (<NUM>) longitudinally arranged with respect to the body;
a second tubular segment (<NUM>) having a distal end (<NUM>) and a proximal end (<NUM>); the second tubular segment further having a body (<NUM>) and a set of spine wires (<NUM>) longitudinally arranged with respect to the body; and
a first connector (<NUM>) having a first portion (<NUM>) connected to the distal end of the first tubular segment and a second portion (<NUM>) connected to the proximal end of the second tubular segment; wherein the first portion and the second portion are engaged so that the first and second portions can rotate with respect to each other.