System for connecting a blood pump with a heart

The subject matter of the present application is a system for connecting a blood pump to a heart, which comprises a blood pump and a connector, which can be attached to an organ, such as a heart, and into which the blood pump can be inserted.

Heart assist pumps, such as Ventricular Assist Devices (VAD), are well known in the art. In addition, there are numerous proposals as to how such pumps can be connected to an organ such as, for example, a heart.

A plurality of the VAD connector systems includes a connector which is anchored, for example, to an apex of a left ventricle, for example, by means of a suture or coil spring. An opening is then cut into the ventricle through which the blood pump can be pushed into the ventricle.

In order to ensure secure attachment of the blood pump to the connector, various systems are known in the prior art. For example, the<patcit id="pcit0001" dnum="US6802806B2"><text>US 6,802,806 B2</text></patcit> A VAD connector system, in which the cardiac pump or a cannula of a cardiac pump can be screwed to a connector. Although the screw connection permits a secure fastening, this has the disadvantage that screwing, for example in the human body, is associated with difficulties.

A further solution is, for example, in the <patcit id="pcit0002" dnum="US8403823B2"><text>US 8403 823 B2</text></patcit> , Which proposes connecting an inlet port of a blood pump to a connector by means of pins. Although a secure connection can also be ensured here, the introduction of the screws in the body is difficult.

Another system is in the <patcit id="pcit0003" dnum="US8152845B2"><text>US 8152845 B2</text></patcit> , Which proposes a seam ring with a cuff attached thereto, which can be slipped over a tubular section of a blood pump and which is securely attached to the blood pump either by means of a clamping force or which can be sewn with the blood pump. Although a secure attachment can also be ensured here, the fastening of the blood pump to the cuff in the body is associated with difficulties.

Another system is in the <patcit id="pcit0004" dnum="US7942805B2"><text>US 7,942,805 B2</text></patcit> Respectively. The system comprises a connector comprising an inwardly acting locking ring which can radially engage a groove of an inlet fitting. The locking ring is thereby radially narrowed by means of a screw so that the ring of the connector engages behind the groove of the inlet connection of the blood pump and axially fixes it. Although secure attachment is possible with this, it is difficult to operate the screw in the body. In addition, a groove is required at the inlet port of the pump, which must be accessed behind.

Another system is from the <patcit id="pcit0005" dnum="EP2524709A1"><text>EP 2 5247 09 A1</text></patcit> known. The system comprises a seam ring which, inter alia, has an annular body with a groove. Two front plates are arranged on the blood pump with a spring body arranged between the front plates. The spring body is shaped in such a way that it can be pushed onto the annular body in a first configuration and can be tensioned in a second configuration so that the groove of the annular body is behind. The spring body is configured such that it is held in a guide body and can be spread apart in order to be guided over the annular body, and subsequently the pressure applied for spreading is released so that the spring body engages behind the groove of the annular body. This makes it possible to reliably engage behind,

It is therefore an object of the present invention to propose a VAD connector system which offers an alternative to the already existing systems.

The object is achieved according to a system according to claim 1 as well as the subordinate and subsidiary claims. The pumps treated here can be, for example, left VADs (LVADs), right VADs (RVADs) or two-sided VADs (BiVADs).

According to the invention, the blood pump for conveying blood comprises a first tubular section, for example an inlet port, and a second tubular section, for example an outlet area of ​​a pump, a flange-shaped section being arranged between the first and second tubular sections. A locking ring, which can be expanded in a guide gap, is arranged in the flange-shaped section of the blood pump, the locking ring preferably being radially expandable. The locking ring is guided in the guide gap and configured to have a first diameter in a first unstressed state and a second diameter in a second, expanded state, the second diameter being larger than the first diameter.

The system further comprises a connector having a tubular connector portion extending between a distal end and a proximal end in an axial direction, having a lumen for receiving the first tubular portion of the blood pump, and a flange-shaped connector portion disposed at the distal end for securing the connector to a connector Organ, such as a heart. In the first tubular connector section there is a wall surrounding the lumen, which at least in sections has an expansion, which is designed in the form of a latching lug.

The ridge-nose-shaped widening widens from the proximal to the distal end and comprises at its distal end a surface to be gripped behind. When the blood pump with the first tubular section is inserted into the lumen in the axial direction, the locking ring strikes the proximal end of the ridge-nose-shaped widening and is widened further as the blood pump plunges further towards the distal end of the connector Has reached its maximum radial extent, and then snaps onto the surface to be gripped behind and behind it. Since the locking ring is initially slowly expanded and then "snapped", there is a clicking sound which gives the person introducing the blood pump an audible feedback, That the blood pump is securely arranged on the connector. In addition, vibrations in the pump housing can be induced by snapping, which give tactile feedback.

Since the locking ring is widened by the latching lug, without the need for additional pressure to expand the locking ring, the physician who instigates the blood pump is free to handle the pump, since he has only to deal with the pushing on. Additional fixing by means of screwing, pressing or suturing, as in some prior art devices, is not necessary. This ensures a high degree of safety during the operation since the person starting the pump does not engage the pump at certain points, but merely has to push the pump axially into the lumen.

Since the tubular sections are mostly cylindrical sections, it is also possible to choose a free radial orientation of the pump when the first tubular section is pushed into the lumen, which adapts to the anatomy of the body. A previous alignment of the connector to the blood pump is not necessary. Since the locking ring engages behind the latching lug and the first diameter of the locking ring can be selected such that the pump is still freely rotatable, the blood pump can be freely rotated by the locking ring after the ratchet-shaped expansion of the connector has been completed. Due to the fact that the locking ring does not engage behind the wall or the ridge-nose-shaped expansion in a second, widened state,

The locking ring therefore engages in the latching lug on the outer side of the connector wall. In this way, it is possible that the first tubular portion pushed into the lumen of the connector can be formed without a groove. A sealing ring can be arranged between the inner wall of the connector and the first tubular section of the blood pump, which creates a fluid-tight seal between the blood pump and the connector. For this purpose, for example, the inner wall of the connector or the tubular section of the blood pump can have a groove with a sealing ring.

Further exemplary embodiments are explained below within the scope of the respective teachings of the subordinate claims.

In one embodiment, the ridge-nose-shaped widening of the wall is designed such that it completely rotates the wall. In this embodiment, the ridge-nose-shaped widening is preferably a closed latching lug, which extends in the axial direction from the proximal to the distal end. In this exemplary embodiment, it is also advantageous if the wall also completely surrounds the lumen. In other embodiments, however, it is possible for the widening to be arranged in axially extending fingers which are spaced apart from each other. Although less material is used in this embodiment, the stability of the fingers is not as high as a fully circumferential wall.

In a further embodiment, the latching lug is configured such that it comprises, at a proximal end, a planar section which corresponds to a flat area of ​​the flange-shaped section of the blood pump so that these planar areas abut one another against the other. As a result, an abutment in the axial direction is formed, so that it is avoided that the pump is pushed too far into the connector. At the same time, the planar sections can be selected in such a way that the position of the pump on the connector is stabilized by the two-sided abutment and an excessive wobbling of the pump is prevented.

In a further embodiment, the guide gap is configured such that it has a width which corresponds to a height of the locking ring, preferably an axial height of the locking ring, so that the locking ring is fixed to the blood pump in the axial direction. In this way, it can be ensured that the blocking ring merely performs a radial movement but not a substantial axial movement. However, the gap width of the guide gap is selected in such a way that the locking ring can be moved radially in the guide gap in a low friction.

In a further exemplary embodiment, the widening and the blocking ring are selected in such a way that the blood pump is held rotatable about the axial direction in the first state engaging behind the catch lug. In this way, the blood pump can be rotated to the desired position after being securely connected to the connector.

As an alternative to the rotatable mounting, the blood pump and connector can be configured in such a way that they are arranged so as to be non-rotatable relative to one another in the first, ie, in a non-rotatable state. In one embodiment, the blood pump comprises a first toothed section. The connector has a second toothed portion, the two toothed portions corresponding to each other, ie the teeth of the respective portions being engageable with one another. While the teeth intermesh, the connector and the blood pump are no longer rotatable, ie they are non-rotatable relative to each other. In order to twist the blood pump against the connector, the locking ring must be released and the blood pump pulled out of the connector in the axial direction. As soon as the toothed portion of the blood pump no longer engages in the toothed portion of the connector, the blood pump can again be twisted against the connector. Once the desired orientation of the blood pump is adjusted, the blood pump is pushed back into the connector and the toothed sections engage one another.

In a further development of the toothed sections of the blood pump and / or of the connector, these are arranged rotationally symmetrical in the axial direction. This ensures that a rotationally fixed fixation is possible in any orientation of the blood pump to the connector. In a continuation, both toothed sections are rotationally symmetrical and corresponding to one another.

In a further exemplary embodiment, the guide gap is open in a radial direction. In this way, the locking ring can not be inserted into the guide gap until a comparatively late point in time during the assembly of the blood pump. This insertion of the locking ring can, however, be effected outside the body or already taken place during the production of the pump. In addition, an open guide slot serves for the fact that during the widening of the locking ring, tissue which has accumulated between the locking ring and the pump is displaced from the open guide gap, and thus the locking ring can also be radially expanded after a prolonged stay in the body. This is necessary, for example, with a pump change or with an explant.

In a further exemplary embodiment, the flange-shaped section of the blood pump has a radial stop which prevents the locking ring from being narrowed to a smaller diameter than the first diameter. This is particularly helpful prior to implantation since damage to the barrier ring can be prevented prior to implantation. The stop can either be provided by the flange-shaped section itself or by means of a further component, a stop ring.

In a further exemplary embodiment, the locking ring has an angled profile, for example an L-shaped profile, a first section of the locking ring being configured to engage behind the ridge-nose-shaped expansion, and a further section which is angled towards the rear-reaching section in such a way that it is arranged on the stop Of the blood pump is radially supported and supported. Due to the support, a constriction of the locking ring to a diameter below the first diameter can be prevented.

In a further exemplary embodiment, the blocking ring is an open blocking ring and comprises an angle segment of, for example, more than 270 °, preferably more than 300 °, preferably more than 330 °, in some exemplary embodiments an open overlapping locking ring with an angle segment of more than 390 °. At one end, the locking ring is fixed to the flange-shaped section of the blood pump, preferably fixedly or positively fixed. For example, the locking ring can be welded to the blood pump, held rotatably in a pin, or fixed in a similar or equivalent manner.

In a further embodiment, the locking ring has a gripping element for transferring the locking ring from the first to the second state. By means of a gripping element of the locking ring protruding radially from the flange-shaped section of the blood pump, the latter can be expanded from the first to the second state.

In a further embodiment, a further gripping element is arranged correspondingly to the gripping element on the blood pump so that the gripping ring is expanded when gripping the gripping element of the locking ring and the gripping element provided on the pump and subsequently joining the two elements. This greatly simplifies explantation of the blood pump. However, it is to be noted that the gripping elements are only necessary for explanting or pumping off the pump. When the pump is pushed onto the connector element, the locking ring is expanded by the latching lug. The gripping element or the corresponding gripping element of the blood pump is merely necessary to effect a widening of the locking ring from the rear-engaging surface of the latching lug.

As already mentioned, the guide gap can be open in a radial direction. Alternatively or additionally, the blood pump in the flange-shaped section or in the second tubular section can have further openings for the displacement of tissue between the barrier ring and the blood pump. This simplifies the explantation of the pump. In some embodiments, only one opening may be provided, in other embodiments more than one opening.

In a further embodiment, the system comprises a jacket which can be placed on the blood pump. In this context, "invertible" is to be understood as meaning that the sheath is, for example, flexible and is later applied to the blood pump. The jacket comprises at least one, preferably inwardly projecting tongue, which engages into the at least one opening of the flange-shaped section of the blood pump. The jacket can be made, for example, from silicone or another soft, biocompatible material. Due to the fact that the tongue projects into the at least one opening, the opening can be prevented from being blocked by a waxing tissue. In the explantation of the blood pump, the sheath can be removed and the few remaining tissue easily displaced from the openings. It is pointed out, That the Applicant will independently pursue the cover within the framework of a partial application for use with a VAD system. The same applies to the toothed sections of the connector and the blood pump.

In a further embodiment, the first tubular section of the blood pump comprises a groove in which a sealing element, for example in the form of a sealing ring, is arranged. Alternatively, the connector may comprise a groove or a sealing ring on the inner side of the wall which circumscribes the lumen.

In the following, some embodiments of a VAD connector system are explained. At this point, it should also be pointed out that both the blood pump itself and the connector per se constitute an independent part of the application and can be followed in the course of further applications.

It shows<dl id="dl0001"><dt>FIG</dt><dd>4 is a schematic view of a pump;</dd><dt>FIG</dt><dd>A schematic view of a connector;</dd><dt>FIG. 3A-C</dt><dd>A cross-section of a pump with a locking ring;</dd><dt>FIG. 3D</dt><dd>A further embodiment of a locking ring;</dd><dt>FIG. 4A, B</dt><dd>A cross-section of a schematic connector;</dd><dt>FIG. 5A-C</dt><dd>Various longitudinal sections through a pump connector system;</dd><dt>FIG. 6A, B</dt><dd>A further embodiment of a pump connector system;</dd><dt>FIG. 7A-C</dt><dd>A further embodiment of a pump connector system; and</dd><dt>FIG</dt><dd>An embodiment of a silicone sheath for the system.</dd></dl>

<figref idrefs="f0001">FIG</figref> Shows schematically a blood pump 10 which comprises a first tubular section 12 and a second tubular section 14 which are coupled to one another via a flange-shaped section 16. The three sections 12, 14 and 16 are aligned coaxially along the axis 18. The first tubular section 12 can serve, for example, as an inlet connection and can be inserted, for example, into the ventricle through the heart wall, depending on the connector system used. The second tubular section 14 includes, for example, a spiral chamber and, in addition, an outlet, not shown here, through which the fluid sucked through the inlet is expelled. In the present embodiment, the tubular portion 12 has an outer diameter D_P1, Which is smaller than the outer diameter of the second tubular portion D_P2.

In <figref idrefs="f0001">FIG</figref> An illustrative connector 30 is shown schematically. The connector 30 includes a flange-shaped connector portion 32 and a tubular connector portion 34 extending along the axis 31 from a distal end disposed at the flange-shaped portion 32 to a proximal end. The tubular connector section comprises a wall with an inner side, into which, for example, the first tubular section of the blood pump of the<figref idrefs="f0001">FIG</figref> Can be inserted. Furthermore, the wall has an outer side 38, an expansion 42 with a snap-in profile being arranged at the proximal end of the outer side 38. The snap-in profile is designed in such a way that the radial width or the diameter widens from a proximal end to a distal end until a rear-engaging surface (not shown) closes off the snap-in profile.

The inner side 38 of the connector 30 has a diameter D_K1, Which is connected to the inlet diameter D_P1 Respectively. The flange-shaped connector portion 32 has an outer diameter D_K2 And can be designed in such a way that, for example, it can have holes on its outer edge for sewing the connector with an element. The connector 30 can, for example, be uniformly formed from a single metal or a metal composition or a plastic. Further, for example, the flange-shaped portion 32 in the region of the tubular connector portion may be made of a metal, while the outer edge of the flange-shaped portion 32 is made of a flexible material which can be easily sewn with an organ. The diameter D_K2 Can be chosen such that this is larger than the diameter D_P2 Of the second tubular section 14 of the blood pump 10 of the <figref idrefs="f0001">FIG</figref>. As a result, improved stability of the blood pump in the state connected to the connector can be achieved.

In the <figref idrefs="f0002">FIGS</figref> A representation of the blood pump 10 is shown in a plane perpendicular to the axis 18. The first tubular section 12, the second tubular section 14 and the flange-shaped section 16 located therebetween are visible with solid lines. Illustrated in dashed lines is an open locking ring 50 whose gripping element 52 extends radially outward of the second tubular section 14. The gripping element 52 is arranged on a gripping end 54 of the locking ring. The locking ring extends over an angle segment of more than 330 ° from its gripping end 54 to the open end 56, where it rests against a stop 58 formed as part of the pump. The stop 58 prevents the blocking ring 50 from being rotated further in the direction 60 when a force is applied to the gripping element in the direction 59. In addition, the L-shaped stop 58 prevents the locking ring from breaking out in the radial direction 62. In this case, the blocking ring 50 can be loosely connected to the pump in a guiding slot, without material, force or positive engagement.

Between the tubular section 12 and the tubular section 14, a recess 70 is formed in the region of the flange-shaped section 16, which recess is also annular and whose width viewed in the radial direction 62 substantially corresponds to the width of the expansion 42 with the latching lug profile. It can be seen that the locking ring shown in its first unstressed state radially engages into the recess 70. The interplay between the ridge-nose-shaped widening 42 and the locking ring 50 is described with reference to FIGS<figref idrefs="f0004">FIGS</figref> In more detail. In the<figref idrefs="f0002">FIG. 3A</figref> Additional stop elements 72 are arranged which are arranged on the blood pump, radially outside the blocking ring. The stop elements prevent the locking ring from being expanded too much radially, and can be made, for example, from silicone, steel or foam material. These stop elements also serve for additional, external centering and can also be used in the other exemplary embodiments of the blood pump or the system. Furthermore, the locking ring has a reduced radial width B1 in the vicinity (for example, a 60 ° segment, viewed counterclockwise) of the stop 58, against a width B2 of the locking ring in other segments. This causes the locking ring to release the ridge-nose-shaped expansion also in the region of the stop. The transition of the width of the locking ring from the width B1 to the width B2 can take place, as shown, gradually, ie over a certain angular segment (for example 10 °), or as a jump. The transition may have a linearly or nonlinearly increasing width from the width B1 to the width B2.

In <figref idrefs="f0002">FIG. 3B</figref> An alternative locking ring 80 is shown. This is essentially identical to the blocking ring 50 of the<figref idrefs="f0002">FIG. 3A</figref>, But is positively held in the guide gap by means of a pin 84 connected to the pump and a corresponding recess of the blocking ring 86. When a force is applied in the direction 89, on the one hand, the locking ring is expanded and the locking ring rotates around the pin 84. In an advantageous embodiment, the locking ring can be positioned within an angular segment counterclockwise by the pin 84, for example 30 ° to 100 °, Preferably from 50 ° to 80 °, so that the locking ring does not project into the recess 70 in the region of the angle segment. Thus, it is avoided that a merely strong stretching of the locking ring releases the latching lug of the connector. In order for the locking ring 86 to be sufficiently expanded even at the height of the pin 84, The ring on the pin 84 is guided in a slotted track 85 which extends along the radial direction of the locking ring. If a force is exerted in the direction of the locking ring in the direction of expansion, the slotted end of the locking ring moves on the slotted track 85 from the position shown in FIG<figref idrefs="f0002">3B</figref> , Until it comes into abutment with the opposite end of the slotted path on the pin 84.

Although in the <figref idrefs="f0002">Figures 3A and 3B</figref> The locking ring is an open locking ring, ie, it can comprise an angle segment of less than 360 °, as shown in FIG <figref idrefs="f0002">FIG. 3C</figref> , The locking ring also enclose an angular range of more than 360 °. The<figref idrefs="f0002">FIG. 3C</figref> Is provided with a first gripping element 92 and a second gripping element 94. The region 96 lying between the two gripping elements is formed by a part of the locking ring located to the left of the gripping element 94 and a partial segment of the locking ring, which is connected to the gripping element 92 on the right, so that the locking ring is provided with two layers in the region 96. By applying pressure to the gripping elements 92 and 94 such that they are pressed towards each other, the locking ring can be widened.

A further exemplary embodiment of a locking ring is shown in FIG <figref idrefs="f0002">FIG. 3D</figref> Respectively. The locking ring 97 is similar to the embodiment of FIG<figref idrefs="f0002">3C</figref> educated. The locking ring 97 has an overlapping region 97 'and two grip elements 98. By pressing the grip elements 98 against one another, the locking ring is expanded.

The connector 30 includes the flange-shaped portion 32 and, as described in the description of FIG <figref idrefs="f0001">FIG</figref> A tubular connector portion 34. A lumen 37 defined by the wall 36 of the tubular portion 34 is shown in FIG <figref idrefs="f0003">FIG. 4A</figref> Recognizable. The lumen 37 has a diameter D_K1. At the proximal end of the tubular connector section 34 there is the ridge-nose-shaped widening 42. The radial diameter of this widened from the diameter D_K1 Up to a larger diameter_R on.

The snap-in profile of the widening is shown in FIG <figref idrefs="f0003">FIG. 4B</figref> In more detail. The connector 30 has the flange-shaped connector section 32 as well as the tubular connector section 34, which has a wall 36 with an outer side 38 and an inner side 40. The inner side 40 of the tubular section 34 has no profiling in the present example. The widening is completely arranged in the region of the outer side of the wall 36. The widening 42 comprises a latching lug 100, the thickness of which in the direction 102 to the rear-engaging surface 104 depends on a first width B_R1 To a second wall width B_R2 Increases.

Alternative profiles of the ratchet profile are also possible. For example, the width B_R1 Substantially equal to zero, so that the latching lug profile has a tip at its proximal end.

The interaction of the blood pump with the locking ring and the connector is to be determined using the <figref idrefs="f0004">Figures 5A-C</figref> To be illustrated in more detail.

In <figref idrefs="f0004">FIG. 5A</figref> A heart wall 1000 is shown, into which, for example, an opening 102 has been introduced by punching. A blood pump 110 is inserted into the opening 102 by means of a connector 130. The pump 110 essentially corresponds to a pump as described in detail in the FIGS<figref idrefs="f0001">FIGS</figref> and <figref idrefs="f0002">3</figref> Has been explained. The connector 130 essentially corresponds to a connector 30 as shown in FIG<figref idrefs="f0001">FIG</figref> Is shown. Thus, the connector 130 also comprises a flange-shaped section 132 as well as a tubular connector section 134 with a widening 142. On the radial edge of the flange-shaped section 132 there is additionally a flexible ring, which is materially connected to the flange-shaped section 132. The ring 136 is sewn with the heart wall 100 by means of seams 138. The blood pump 110 includes inter alia a locking ring 150, which is guided in a guide gap 160. In the embodiment shown in FIG<figref idrefs="f0004">FIG. 5A</figref> The blood pump 110 is pushed into the tubular connector section in the axial direction 170. It can be seen that the inner diameter 152 of the locking ring in the unstressed state is smaller than the largest outer diameter of the expansion 142. When the blood pump 110 is pushed onto the connector 130 in the direction 170, the locking ring also strikes the expansion and gradually passes through the diameter Increasing widening until the distal end of the latching lug is reached and the locking ring as shown in FIG<figref idrefs="f0004">FIG. 5B</figref> Is shown, behind the catch lug. In this state, which catches the detent, the locking ring is preferably unloaded, that is to say it assumes its form without the applied voltage.

It is clearly apparent to the person skilled in the art that the blood pump 110 in the embodiment shown in FIG <figref idrefs="f0004">FIG. 5B</figref> The first, preferably unstressed, state of the locking ring is rotatably mounted about the axis 118. In order to, for example, expose the blood pump 110, a force can be applied by the gripping element 154 of the locking ring 150 projecting radially from the second tubular section 114 so that the locking ring 150 is expanded in such a way that the section of the tubular connector section 134, Is released or the expansion is no longer traced behind, and the pump 110 can be explanted in the axial direction 190. This is done in<figref idrefs="f0004">FIG. 5C</figref> illustrated.

In <figref idrefs="f0005">FIG. 6A</figref> A further exemplary embodiment of a VAD connector system is shown. Only a profile section of the axes 218 of the blood pump or 331 of the connector is shown radially outwards. The system comprises a blood pump 210 and a connector 300. The connector 300 essentially corresponds to the already discussed connectors 30 and 130, respectively. The connector comprises a flange-shaped section 332, which comprises openings 333, through which a seam 400 can be guided Shaped connector section 332 to a heart wall 410. The tubular section 334 of the connector 300 has, at its proximal end, a widening 342 in the form of a latching lug, which at its most proximal end comprises a flat section 344 having a width B_R1 And which extends in the distal direction over a height 348 up to a width B_R2 Expands At the distal end of the latching lug there is a surface to be gripped which has a width of B_R3 Which corresponds to the difference B_R2 - B_R1 Respectively. There is no profiling on the inner wall of the tubular section 334.

The blood pump 210 includes a first tubular portion 212 which includes a groove 280 in which a sealing ring 290 is disposed to form a seal between the inner wall of the tubular connector portion 334 and the first tubular portion 214. From the flange-shaped section 216 to the second tubular section 214 of the blood pump 210, a locking ring 250 extends, inter alia, which is guided in a guide gap 260 and is configured such that, in the unloaded state, it engages behind the surface 346 to be gripped, For example in the description of the<figref idrefs="f0004">FIGS</figref> Can be expanded so that the blood pump 210 can be withdrawn from the connector 300. The guide gap 260 receives a first section 252 of the locking ring 250, the width of the guide gap in the axial direction of the guide gap 260 being selected such that the width substantially corresponds to the height of the section 252 in the axial direction so that the locking ring 250 is not an axial, Game.

Furthermore, the locking ring 250 comprises an angled region 254, which can be held radially on a stop surface 272 of a stop ring 270. An external radial stop 274 of the flange-shaped section 116 of the blood pump is located radially outward of the stop 272. A recess 278, which has a width B, is provided between a radially inner region of the abutment 276 and the first tubular section 214_R2 Which substantially corresponds to the width of the largest diameter of the flare 342. At the proximal end, the widened portion 342 has a flat portion 344 corresponding to a planar portion 216 'of the flange-shaped portion 216. Between the blocking ring 250 and a wall 214 'of the blood pump there is a cavity 282, which can fill with tissue in the case of a prolonged stay of the blood pump in the organic tissue. In order that this tissue does not restrict the mobility of the locking ring during explantation, provision is made for introducing, in the abutment ring 270, channels 284 which open into openings 286 of the second tubular section 214.

This is in <figref idrefs="f0006">FIG. 6B</figref> Again in a view. The tubular section 214 has an opening 286, the stop ring 270 having channels 284 through which material located in the chamber 282 can be ejected in the radial direction during expansion of the locking ring. In this way, the blocking ring is prevented from being blocked in the indented state.

In the <figref idrefs="f0006 f0007">Figures 7A-C</figref> A further alternative of a VAD connector system is shown.

The blood pump 500 is connected to a connector 600. The blood pump comprises a blocking ring 510, which has a gripping surface 520. The abutment ring 530 was inserted into a guide gap and defines a guide gap which substantially corresponds to the height of the locking ring. The connection ring was subsequently welded to the pump.

A section of the <figref idrefs="f0006">FIG. 7A</figref> Is shown in FIG <figref idrefs="f0007">FIG. 7B</figref> Respectively. In addition to the blood pump 500 and the connector 600, a silicone jacket 700, which can be turned over by means of the blood pump, is also shown whose functionality is still described.

The blood pump 500 comprises a flange-shaped section 540 which has a radius comparable to the second tubular section 550 and which, inter alia, comprises the abovementioned locking ring and abutment ring. Alternatively, the radius of the flange-shaped portion 540 may be selected to be smaller than the radius of the second tubular portion. The flange-shaped portion 540 is selected only larger than the first tubular portion 560. The Silicone Jacket 700 is detailed in<figref idrefs="f0007">FIG</figref> Respectively.

In <figref idrefs="f0007">7C</figref> A toothed section 570 arranged on the blood pump and a toothed section 610 arranged at the connector and corresponding to the section 570 are shown. In the illustrated first state (ie, the blood pump is inserted into the connector), the teeth of the section 570 are engaged with the teeth of the section 610 and prevent the blood pump from twisting against the connector, ie, the blood pump and connector are non-rotatable connected. When the blood pump is pulled out of the connector by the height of the teeth, the blood pump is again rotatable, and a different orientation of the blood pump can be adjusted relative to the connector.

In the present example, both the toothed portion 570 and the toothed portion 610 are circular in shape. In this way, any orientation of the blood pump opposite the connector can be adjusted and the orientation can be maintained non-rotatably.

The toothed sections can, for example, be formed from a biocompatible material with a metal or a plastic. The teeth are preferably inflexible or have a sufficient hardness so that twisting of the sections with respect to one another is not possible.

In <figref idrefs="f0007">FIG</figref> The silicone jacket 700 is shown. This comprises a first jacket surface 710, which rests on the second tubular section 550. Furthermore, the silicone sheath comprises a plurality of tongues 720 and 730, respectively, which engage in openings of the flange-shaped section 540 (see FIG<figref idrefs="f0007">FIG. 7B</figref>). Due to the engagement of the tongues, tissue can not penetrate completely into the openings and fill the openings, but only to a very small extent grow into the gaps between the tongues and the edges of the openings, so that the blocking ring is inserted during explantation of the pump despite a waxed tissue Disconnect the blood pump from the connector.

Irrespective of the tongues, the silicone jacket 700 can comprise an opening 740, through which a handle of the locking ring can extend.