Steerable guide catheter assemble

The present invention relates to a flexible guide catheter assembly with improved controllability of the distal end portion.

Guiding catheters are used in many fields of medicine. So is for example, a cardiac catheter disclosed in DE 37 18 139 C1 in the form of a hose, the distal end of a probe for locating pathological areas with a Electrode assembly is provided. To certain areas such as the heart be able to control quickly and efficiently in an orthogonal orientation is, special guide catheter necessary. For this purpose, in the literature reference "<i>Suppl. 1 to Journal of Cardiology, Volume 83 (1994)</i>"A guiding catheter discloses two mutually perpendicular planes of curvature. So could the use of different combinations of Radii and angles specifically all Endokardareale be achieved.

The disadvantage of this catheter is that it due to its predetermined Form is only limited usable. Once a different combination is desirable for radii and angles, has a new catheter be used. A further disadvantage is represented by the predetermined Curvature difficult introducing a working instrument.

In DE 93 14 543 U1, a flexible guide catheter is disclosed having a Working channel and a tubular sheath having a helical Outside winding with a defined slope angle of non-stretchable material and an up having a longitudinally extending chamber. Is in this chamber introduced a liquid medium, to move the turns due to this radial pressurization in various fields in different ways relative to each other. This circumferentially uneven shift is an angled portion of the guide catheter caused. If the pressure load then reduced again, affects the elasticity of the shell as a restoring force and the guiding catheter returns to its original shape. This results first the disadvantage that their use of with this design a liquid medium very complicated to be filled chamber is furthermore is disadvantageous in that the catheter has a relatively due to this construction having large outside diameter, resulting in that the distal end for example may be advanced through the coronary ostium hardly addition. After all there is still the drawback that the catheter is defined due to the Outer angle of the slope of the winding very limited use is, that it is far from all the desired bending to achieve to all points of a three-dimensional space at the distal to reach the end of the guide catheter.

The DE 91 00 016 U1 teaches a guiding catheter with a sufficiently small Outside diameter by through the longitudinal passageway of the guiding catheter is not equal to the tools may be advanced, but first a second Guide catheter. This second guide catheter - in the then Tools are advanced - has for its flexibility not braided Layer more on as the first, since it the first spurt. Thus he is as thin, that its outer diameter is lower and it via the coronary Ostium addition can be advanced. Thus, a disadvantage of the previously discussed document avoided. Allen said documents but still have the common disadvantage that only limited deformations the catheter due to the braided layer are possible.

In contrast, it is an object of the present invention to provide a catheter, is the almost perfectly controllable, ie the different at the distal end Radii and angles at one and the same catheter permits without a catheter change is necessary. In addition, it is an object, to provide a means that many different rotational or tilting movements of the catheter to a substantially fixed axis allows to achieve all Points of a three-dimensional space in the region of the distal end of the catheter to achieve, thus z. B. in a hollow organ.

The object of the invention is achieved with the features of claim 1. It a flexible guide catheter having a pre-shaped and with a Working lumen for feeding tools provided inner catheter provided, the inner catheter with at least one outer tube is provided which is thicker and more rigid than the inner catheter and because of its Periphery at the inlet opening can be supported in one body, wherein the preformed inner catheter at its inside the outer tube adapting form and stretched, but outside of the outer tube in the body resumes its pre-formed shape. This enables each feed position the inner catheter realize different curvatures, wherein the outer tube upon further advancing a tilting movement about the performs inlet orifice of the organ, so that there arises a stable axis of rotation and continuously at any point of a three-dimensional space without exchange the working instrument can be achieved.

An advantage of the invention is that one by the use of flexible but with different radii of curvature and levels preformed Inner catheter and at least one additional thicker, stiff and applied on the inner catheter outer tube through which the inner catheter is advanced, depending on the length of the hose from the outside in the Organ protruding inner catheter different curvatures on the inner catheter can be realized. The inner catheter has a working lumen, can be advanced through the then any work tools.

Another advantage of the invention is that by the use of the additional thicker outer tube means is provided, which makes it possible that the outer hose at the inlet opening to the organ can be supported and so that a turning or tilting movement of the catheter can be produced, namely, when the outer tube at the free feeding thereof is not moved further into the institution, but at the inlet opening is stopped and a tilting movement performs.

Other objects and advantages of the present invention will become apparent from the following part of this description and the accompanying drawings which show a presently preferred embodiment and to which the principles of the invention are explained.<dl tsize="10"><dt>Fig. 1</dt><dd>shows a preformed flexible inner catheter.</dd><dt>FIG. 2a / b</dt><dd>show the catheter assembly according to the invention with the partially from the outer tube excellent inner catheter different curvature depending on the relative feed position. </dd><dt>Fig. 3a / b</dt><dd>show the tilting movement of the outer tube at the free feeding thereof against the inlet opening in an organ.</dd></dl>

Fig. 1 illustrates the pre-formed inner catheter 1. It consists of medically acceptable elastic plastic material, which in a certain way is permanently preformed, which also stretched because of its elasticity or can be bent into different shapes when external forces are applied. Of the Inner catheter of FIG. 1 is in particular characterized in that the end portion the catheter axially inwardly from the distal end having longitudinally variable radii of curvature and / or each other in different, eg. vertical or inclined planes of curvature preformed so and something is stiffer, that he no external force by itself about the in Fig. 1 indicated three-dimensional shape, or a similar three-dimensional Shape in space occupies. As also shown in FIG. 1 can be seen, can other hand, the closer to the proximal end of the inner catheter at the illustrated end portion subsequent (main) part of the catheter quite "Straight" but its more of a flexible nature, as with conventional catheters usually is the case. The thus "preformed" and formed inner catheter 1 extending in the longitudinal direction with a fact "Working lumen" (not shown in the drawings) is in the in diameter slightly thicker outer tube 2 or outer catheter is inserted, the more resistant to bending than the above-described front end portion of the inner catheter 1, which has the consequence that the entire end portion at the by external Influences forced bends the outer tube 2 matches, while Inner catheter is still inside the outer tube. Without these but external guidance he takes his permanently preformed shape (Fig. 1).

This is evident in the figures 2 a / b, which at the same time the basic principle the invention illustrate. The preformed with different radii of curvature Inner catheter 1 is thicker and more rigid outer tube 2 out and during insertion of the catheter assembly together first pushed forward with this forward. Within the outer tube adapts the curvature of the inner catheter of the given external circumstances Shape of the outer tube, and in particular also the specially preshaped distal end portion of the inner catheter. However, depending on the length, protrudes to the front end portion of the outer tube, takes the inner catheter axially more back outside thereof or less its preformed Shape. So can be, depending on the feed position of the inner catheter in relation to the distal end of the outer tube due to the pre-formed shape of the inner catheter different curvatures or locations realize the distal end of the inner catheter, that is it can almost arbitrary points inside z. B. a hollow organ can be achieved. In order to you are in possession of a flexible and well controllable catheter assembly, Change without this depending on the desired shape of the end portion to have to. Furthermore, there is the advantage that a catheter change, if nevertheless necessary, can be limited to the exchange of the inner catheter, without a new outer tube must be inserted. At the same time guarantees the thicker and more rigid outer tube a firm grip, a more stable Positioning and an increased rotational stability of the catheter system.

This property of the outer tube can now continue to be used, As can be seen in Fig. 3 A / B, showing another principle of the invention. There the outer tube due to its larger circumference or diameter supported at the inlet opening in a further body and thus not further can penetrate into the hollow organ 3, it performs when he still further is advanced, with the inserted beyond the inlet opening catheter segment a tilting movement of the inlet opening in the organ. These Tilting movement acts as a rotational axis about which the outer tube - and also the inner catheter - can be pivoted. This leads to a further Degree of freedom in motion with a fixed stop on the axis of rotation, so that continuously virtually all points of a three-dimensional space -. eg a Hollow organ - can be achieved.

The manner of use of the catheter assembly is briefly explained below:<sl><li>1. After puncture of a blood vessel, a vein or artery, is a guidewire set (Seldinger Technique).</li><li>2. First, the thinner, introduced by a in its lumen dilator stretched, and because a long, protruding from the outer tube inner catheter introduced over the guide wire into the blood vessel.</li><li>3. Following the introduction of the protruding segment of the inner catheter is Duch stretching the elastic layers of the skin and the vessel wall and the thicker, introduced horse over the inner catheter outer tube into the blood vessel and simultaneously advanced to the inner catheter until the catheter tip the controlled heart or vascular segment has reached.</li><li>4. Then, the dilator and guidewire are removed and the inner catheter can now accept his predetermined curvatures.</li><li>5. Through the working lumen of the inner catheter can now desired advanced tools like laser catheter, electrode catheters, Biopsziezange or the like. will.</li><li>6. By the retraction of the inner catheter in the outer tube or by advancing it over the inner catheter, the curvatures of the end portion can be varied as required.</li><li>7. In addition, the inner tube can be with or without the outer tube to its own axis to rotate.</li><li>8. If the inner tube into an organ, such as another heart cavity, introduced (Eg transseptal puncture), the distal end of the outer tube can be up to out the organ and there because of its larger scale at the entry point are supported.</li><li>9. Now, the movements described above with the inner catheter with tilting motions of the inner catheter around the axis at the entry opening be combined with the institution, whereby this tilt / swing movement the feed of the outer tube results.</li></sl>

Through the catheter assembly according to the invention, the catheter is not as in the prior art along the predetermined path of a blood vessel maneuvered over a guide wire, but by advancing or Retraction of the outer catheter or the outer tube over the preformed inner catheter is the orientation of the distal segment or End portion of the inner catheter changed in the cavity (heart). Thereby can run in the inner lumen of the inner catheter working tool (Optical fiber, etc. Biopsziezange) continuously variable and controlled moves and are used, ie, the pre-formed but flexible plastic inner catheter performs its continuously variable curvatures which in its central lumen located instrument thus to any position of the Hollow organ (heart) can be performed.