Catheter Device for Implanting a Medical Device
20220152382 · 2022-05-19
Assignee
Inventors
- Nicholas Devich (Tualatin, OR, US)
- Eric Austin (Portland, OR, US)
- Hannes Kraetschmer (West Linn, OR, US)
Cpc classification
A61B17/3468
HUMAN NECESSITIES
A61M25/0147
HUMAN NECESSITIES
A61N1/3756
HUMAN NECESSITIES
A61M2025/0161
HUMAN NECESSITIES
International classification
Abstract
A catheter device for implanting a medical device comprises a steerable catheter, and a delivery catheter extending through the steerable catheter and being configured to interact with the medical device for implanting the medical device at an implantation site within a patient, wherein the delivery catheter is axially movable with respect to the steerable catheter. The steerable catheter comprises a first steering articulation zone and a second steering articulation zone arranged distally with respect to the first steering articulation zone, wherein the steerable catheter is steerable by a deflection in the first steering articulation zone and the second steering articulation zone.
Claims
1. A catheter device for implanting a medical devices, comprising: a steerable catheter, and a delivery catheter extending through the steerable catheter and being configured to interact with the medical device for implanting the medical device at an implantation site within a patient, wherein the delivery catheter is axially movable with respect to the steerable catheter, wherein the steerable catheter comprises a first steering articulation zone and a second steering articulation zone arranged distally with respect to the first steering articulation zone, wherein the steerable catheter is steerable by a deflection in the first steering articulation zone and the second steering articulation zone.
2. The catheter device of claim 1, wherein the delivery catheter non-steerable.
3. The catheter device of claim 1, further comprising a steering device which is actuatable for actively causing a deflection in at least one of the first steering articulation zone and the second steering articulation zone.
4. The catheter device of claim 3, the steering device comprises a pull wire.
5. The catheter device of claim 3, further comprising a handle device arranged at a proximal end of the steerable catheter and comprising at least one actuation member configured to control said steering device for causing a deflection in the at least one of the first steering articulation zone and the second steering articulation zone.
6. The catheter device of claim 1. wherein at least one of the first steering articulation zone and the second steering articulation zone is not actively steerable.
7. The catheter device of claim 1, wherein at least one of the first steering articulation zone and the second steering articulation zone is formed by a shape-set curve.
8. The catheter device of claim 1, wherein the first steering articulation zone comprises a first length and/or a first bending radius and the second steering articulation zone comprises a second length and/or a second bending radius, wherein the first length is different than the second length and/or the first bending radius is different than the second bending radius.
9. The catheter device of claim 1, wherein the steerable catheter comprises a straight shaft section arranged proximally of the first steering articulation zone.
10. The catheter device of claim 1, wherein a protective cup arranged on the steerable catheter for sheathing the medical device.
11. The catheter device of claim 1, further comprising: a mandrel received in an inner lumen of the delivery catheter and movable with respect to the delivery catheter, an adapter piece connected to the mandrel, wherein the adapter piece, by moving the mandrel with respect to the delivery catheter, is displaceable between a first position in which the adapter piece is received within the inner lumen of the delivery catheter and a second position in which the adapter piece is arranged outside of the inner lumen of the delivery catheter, and a tethering member comprising a tether portion having a first end at which the tethering member is connected to the adapter piece, wherein the tethering member further comprises a positive-locking member adjoining the tether portion at a distance from the first end, wherein the positive-locking member in a connection state is received on the adapter piece and is locked with respect to the adapter piece while the adapter piece is in the first position, and wherein the positive-locking member is releasable from the adapter piece by displacing the adapter piece from the first position towards the second position.
12. The catheter device of claim 11, wherein the positive-locking member comprises a first diameter, measured along a plane perpendicular to a longitudinal axis of extension of the tethering member, larger than a second diameter of the tether portion.
13. The catheter device of claim 11 of 42, wherein the adapter piece comprises a body and a retainer groove formed on the body, wherein the tether portion in the connection state is received in the retainer groove
14. The catheter device of claim 13, wherein the adapter piece comprises a recess formed on the body and adjoining the retainer groove, wherein the positive-locking member in the connection state is received in the recess.
15. An assembly comprising a catheter device of claim 11 and a medical device having a housing and a connection member arranged on the housing, wherein the tether portion of the tethering member in the connection state is connected to the connection member in that the connection member comprises an opening through which the tether portion extends in the connection state.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0057] The various features and advantages of the present invention may be more readily understood with reference to the following detailed description and the embodiments shown in the drawings. Herein,
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DETAILED DESCRIPTION
[0082] Subsequently, embodiments of the present invention shall be described in detail with reference to the drawings. In the drawings, like reference numerals designate like structural elements.
[0083] It is to be noted that the embodiments are not limiting for the present invention, but merely represent illustrative examples.
[0084]
[0085] For implantation the implantable medical device 1 by means of a catheter device 2 is placed at an implant location, for example in the right ventricle RV—as illustrated in
[0086]
[0087] During implantation the implantable medical device 1 is to be placed at an implant location, for example on myocardial tissue M, and is to be fastened to tissue at the implant location. For this, the implantable medical device 1 comprises an anchoring device 12 having a multiplicity of anchoring members 120 in the shape of tines, wires or tubes or the like, the anchoring members 120 extending from the housing 10 of the implantable medical device 1 at the distal end 100 in order to engage with tissue for fastening the implantable medical device 1 to the tissue.
[0088] For implantation the implantable medical device 1 is to be delivered towards the implant location by means of a catheter device 2, the catheter device 2 comprising a delivery catheter 20 guided within a steerable catheter 24. The catheter device 2 for implantation is guided for example through the inferior vena cava into the patient's heart to access, via the right atrium RA and across the tricuspid valve TV, the right ventricle RV. During delivery the implantable medical device 1 is fixed to the delivery catheter 20, but is to be released once the implantable medical device 1 has reached the implant location and is fixed to tissue in the region of the implant location.
[0089] When the implantable medical device 1, by means of its distal end 100, is placed on tissue at the implant location, the anchoring members 120 of the anchoring device 12 come into engagement with the tissue such that the medical device 1 is mechanically fixed to the tissue. Herein, once the medical device 1 is placed on the tissue at the implant location, a testing is to be performed in order to ensure the mechanical fixation of the medical device 1 to the tissue and in addition to test the proper functionality of the medical device 1, in particular for performing a pacing operation for example in the right ventricle RV of the patient's heart.
[0090] Referring now to
[0091] The delivery catheter 20 comprises an inner lumen 201 in which, in the illustrated embodiment, a mandrel 23 is received, the mandrel 23 extending through the entire length of the delivery catheter 20 towards a proximal end of the catheter device 2. The mandrel 23 is sufficiently flexible such that it may be deformed together with the delivery catheter 20 when guiding the catheter device 2 through body portions of the patient, but at the same time is flexurally rigid and kink-proof such that it may be axially moved with respect to the delivery catheter 20.
[0092] The catheter device 2 furthermore comprises an adapter piece 22 fixedly connected to the mandrel 23, for example by welding. The adapter piece 22 has a generally longitudinal shape with rounded tips and is designed such that it may be received within the inner lumen 201 of the delivery catheter 20 when it is retracted into the delivery catheter 20 by means of the mandrel 23.
[0093] The adapter piece 22 is part of a tethering mechanism comprising a tethering member 21, which at an end 210 is fixedly connected to the adapter piece 22, for example by welding. The tethering member 21 has a tether portion 212 extending from the adapter piece 22 and, at an end opposite to the end 210, is adjoined by a positive-locking member 211 in the shape of a spherical ball, as visible from
[0094] In a connection state, the positive-locking member 211 is received within a recess 222 formed on a body 220 of the adapter piece 22. In the connection state, herein, the tether portion 212 is received within a retainer groove 221 adjoining the recess 222, the retainer groove 221 having a width such that the tether portion 212 may be snuggly placed within the retainer groove 221, but the positive-locking member 211 having a wider diameter is prevented from passing through the retainer groove 221.
[0095] The tethering member 21 serves to establish a connection in between a medical device 1 to be implanted and the catheter device 2. In the connection state the positive-locking member 211 at the far end of the tether portion 212 of the tethering member 21 is received in the recess 222 of the adapter piece 22, and by retracting the adapter piece 22 into the inner lumen 201 of the delivery catheter 20 the form locking connection in between the adapter piece 22 and the positive-locking member 211 is locked.
[0096] This is illustrated in
[0097] In this respect it should be noted that circumferential wall of the delivery catheter 20 should have a structural stiffness such that the ball-shaped locking member 211 cannot deform the wall towards the outside to disengage from the adapter piece 22. In particular, the wall shall comprise such a stiffness that the tether portion 212 cannot disengage from and be pulled off the adapter piece 22.
[0098] When the positive-locking member 211 is received on the adapter piece 22 and when the adapter piece 22 is retracted into the inner lumen 201 of the delivery catheter 20, the tether portion 212 of the tethering member 21 forms a loop which extends through an opening 130 formed on a connection member 13 of the implantable medical device 1, as this is illustrated in
[0099] In a delivery state, herein, the adapter piece 22 is retracted into the delivery catheter 20 in a proximal direction P as indicated in
[0100] Once the medical device 1 has reached the implant location and, by means of the anchoring device 12, has engaged with tissue at the implant location, the medical device 1 shall be released from the catheter device 2. The release herein shall take place in phases in order to, in an initial release phase, allow for a testing on the medical device 1 and, in a second release phase, then fully release the medical device 1 from the catheter device 2 such that the catheter device 2 may be removed while the medical device 1 remains at the implant location.
[0101] In the initial release phase, the adapter piece 22 is moved, within the inner lumen 201 of the delivery catheter 20, in a distal direction D as illustrated in
[0102] In this initial release phase a fixation assessment (a so-called tug test) may be performed by pulling on the medical device 1 in order to ensure a proper fixation of the medical device 1 on tissue by means of the anchoring device 12. Such tug test may for example be performed by moving the mandrel together with the adapter piece 22 in the proximal direction P. In addition, an electrical testing of the functionality of the medical device 1, for example a leadless pacemaker device, may be performed to ensure a proper functionality of the medical device 1, while the medical device 1 is allowed to sit freely on tissue and substantially is not affected by a force action of the tethering member 21.
[0103] If during this testing it is found that the medical device 1 does not securely hold on the tissue, but is released when applying a defined force during the tug test, or if it is found that the medical device 1 is not positioned correctly for performing its electrical functioning, the medical device 1 may have to be repositioned. For this, the adapter piece 22 may again be retracted into the delivery catheter 20 by pulling the mandrel 23 and together with the mandrel 23 the adapter piece 22 in the proximal direction P such that the medical device 1 again comes to engage with the alignment device 200. The medical device 1 may then be positioned at another location, and testing may be repeated until a proper positioning and functioning of the medical device 1 is confirmed.
[0104] Once it is found that the medical device 1 is properly implanted and fixed on tissue and in addition functions correctly, the medical device 1 is to be released from the tethering member 21. For this, the adapter piece 22 is, by pushing on the mandrel 23 in the distal direction D, moved out of the inner lumen 201 of the delivery catheter 20, as this is shown in
[0105] The releasing of the positive-locking member 211 from the adapter piece 22 herein is supported by a slanted face 223 at the transition of the recess 222 and the retainer groove 221, as this is apparent from
[0106] In the connection state, the tether portion 212 extends through an opening 130 of the connection member 13 of the medical device 1, as this is illustrated in
[0107] Once the positive-locking member 211 is passed through the opening 130, the medical device 1 is free of the tethering member 21 and the connection in between the catheter device 2 and the medical device 1 is fully released.
[0108] As visible from
[0109] For pulling the tethering member 21 through the opening 130, the mandrel 23 together with the adapter piece 22 is moved in the proximal direction P into the delivery catheter 20. Once the connection to the medical device 1 is fully released, the delivery catheter 20 may be removed from the patient.
[0110] The tethering member 21 may be made of a radiopaque material such that the positioning of the tethering member 21 may be visualized by an X-ray technology during implant.
[0111] In the embodiment of the connection member 13 of the medical device 1 of
[0112] In another embodiment shown in
[0113] In a different embodiment shown in
[0114] Referring now to
[0115] Referring now to
[0116] As shown in
[0117] A steering by means of the steerable catheter 24 is achieved using the steering articulation zones 241, 243. Herein, as shown in an enlarged view of a proximal portion of the catheter device 2, the first steering articulation zone 241 is arranged proximally with respect to the second steering articulation zone 243 and comprises a length L1 which is larger than a length L2 of the second steering articulation zone 243. In the respective steering articulation zone 241, 243 the steerable catheter 24 may deflect such that the catheter device 2 may be navigated through tighter structures within the patient, for example across the tricuspid valve TV in order to enter the right ventricle RV of the patient's heart to deliver a medical device 1 towards an implantation site for example at the apex or the septum of the right ventricle RV.
[0118] As visible from
[0119] The steering articulation zones 241, 243 may be actively or passively deflectable for providing for a steering.
[0120] An active steering may for example be achieved using steering devices 26, 27 in the shape of pull wires, as shown in
[0121] In one embodiment, as shown in
[0122] The steering device 26 associated with the actively steerable steering articulation zone 243 in this case at a fixing location 260 is connected to the steerable catheter 24, as shown in
[0123] In another embodiment, as shown in
[0124] The steering articulation zones 241, 243 may be actively deflectable in one direction using a single steering device 26, 27. Alternatively, one or both of the steering articulation zones 241, 243 may be deflectable in two or more directions, such that the steerable catheter 24 in the respective steering articulation zones 241, 243 may deflect in a plane perpendicular to the longitudinal axis of extension of the catheter device 2.
[0125] In another embodiment, one or both of the steering articulation zones 241, 243 may be passively deflectable in that one or both of the steering articulation zones 241, 243 are formed by shape-set curves. In this case, the respective steering articulation zone 241, 243 has a predefined, preshaped curvature such that the respective steering articulation zone 241, 243 in a relaxed state without forces acting onto the steering articulation zone 241, 243 assumes its predefined bent shape. In this case, a deflection for steering and navigating the catheter device 2 may be caused in combination with an introducer 3 (see for example
[0126]
[0127] In the shown embodiment, the handle device 25, by means of the actuation members 250, 251, serves to actively control a deflection at the two steering zones 241, 243 in that the steering articulation zones 241, 243 may be actively deflected by adjusting the actuation members 250, 251. In the shown embodiment the actuation members 250, 251 have the shape of steering knobs which may be rotated on the handle device 25 in order to act onto steering devices in the shape of pull wires 26, 27 in order to exert a pulling action on the steering articulation zones 241, 243.
[0128] An additional actuation member 252 serves to adjust the delivery catheter 20 axially with respect to the steerable catheter 24 in particular for deploying the medical device 1 upon reaching an implantation site. The actuation member 252 has the shape of a slider which may be axially moved on the handle 25 in order to advance the delivery catheter 20 proximally for deploying the medical device 1.
[0129] The delivery catheter 20 extends through the handle device 25 and through the steerable catheter 24. At its proximal end the delivery catheter 20 herein is connected to a tether control 203 for controlling movement of the mandrel 23 with respect to the delivery catheter 20. The tether control 203 may in particular be configured to prevent an unintentional actuation of the mandrel 23, the tether control 203 being configured to prevent, in a delivery state of the catheter device 2, that the mandrel 23 may be pushed into the delivery catheter 20 in the distal direction D, by which movement otherwise the adapter piece 22 may be caused to exit from the delivery catheter 20 allowing the positive-locking element 211 hence to disengage from the adapter piece 22.
[0130] The tether control 203 in combination with the mandrel 23 and a wire clamp 230 arranged on the mandrel 23 may be designed such that the mandrel 23, in a non-actuated state of the tether control 203, can be moved in the distal direction D with respect to the delivery catheter 20 only such far that the adapter piece 22 at the distal end of the delivery catheter 20 cannot exit from the delivery catheter 20. By means of the tether control 203 hence a release of the positive-locking member 211 from the adapter piece 22 is prevented.
[0131] By actuating the tether control 203 the mandrel 23 may be released such that the mandrel 23 may be passed through the tether control 203 and may be advanced further in the distal direction D through the delivery catheter 20 to cause the adapter piece 22 to exit from the delivery catheter 20 for releasing the medical device 1 from the catheter device 2.
[0132] For implantation the catheter device 2 may be advanced into a patient using an introducer 3, as this is shown in
[0133] The introducer 3 in the example of
[0134] When further advancing the catheter device 2, a further steering may be achieved once the first, proximal steering articulation zone 241 exits from the introducer 3, as shown in
[0135] As visible from
[0136] Once the implantation site is reached, the medical device 1 is deployed, as shown in
[0137]
[0138] During delivery, as illustrated in
[0139] Once the implant location is reached and the medical device 1 is deployed from the protective cup 244 and hence is placed on tissue in the region of the implant location, as illustrated in
[0140] Once the testing has successfully been concluded, the adapter piece 22 is further advanced in the distal direction D by moving the mandrel 23 until the adapter piece 22 exits from the delivery catheter 20, as this is illustrated in
[0141] By now retracting the adapter piece 22 in the proximal direction P into the delivery catheter 20, as illustrated in
[0142] In a release state, shown in
[0143] If during the testing it is found that the medical device 1 is not properly placed on tissue and/or that the implantation site potentially is not suitable for the medical device 1, the medical device 1 may again be pulled tight towards the alignment device 200 and may be re-sheathed by advancing the protective cup 244 over the medical device 1, such that the medical device 1 may be repositioned and placed at a different implantation site or may be removed entirely from the patient anatomy.
[0144] In one embodiment, the catheter device generally comprises a delivery catheter that is connected to the implant protective cup that is used to sheathe and unsheathe the implant and its fixation mechanism. The delivery catheter has two distinct articulation areas.
[0145] The distal steering articulation zone is a short length tight radius steering deflection along the xy axis that is used primarily for crossing the tricuspid valve efficiently and for deploying the implant into the mid to lower septum. The embodiments for the distal articulation zone could comprise either an articulatable distal curve in a single direction via the handle (current design embodiment), an articulatable bi-directional distal curve via a handle actuator, or a shape-set distal curve with no articulation on the handle.
[0146] The proximal steering articulation zone, in one embodiment, is a longer length relaxed radius steering deflection along the xy axis that is used primarily for navigating to and deploying the implant into the apex within the right ventricle. The embodiments for this proximal articulation zone could comprise either an articulatable proximal curve via a handle actuator, or a shape-set proximal curve with no articulation via a handle actuator.
[0147] The catheter design is also designed to incorporate a tether mechanism technology.
[0148] The handle design includes a means to steer each steerable articulation zone independently from one another. One embodiment comprises two steering knobs on the handle. However, another means would be a single steering knob or actuator that could toggle between each steering deflector. The handle is mechanically designed to that when the user removes their hand from the handle, the deflection of the catheter at any given point is maintained and no relaxation of the catheter to its zero state occurs.
[0149] Lastly, the handle and catheter is designed with a slider to deploy the implant by pushing the implant out of the implant protective cup and into the heart wall. The implant is designed to be attached to the catheter via the tether mechanism which pulls the implant flush against the alignment cup/non-steerable delivery catheter. The non-steerable delivery catheter is mechanically attached to the deployment slider. When the deployment slider is advanced distally from its proximal starting/sheathed position, the non-steerable delivery catheter is advanced distally at the same rate which pushes and deploys the implant out of the implant protective cup.
[0150] The present design may comprise one or more (or all) of the following features: [0151] A delivery catheter that has a high degree of control and maneuverability via the incorporation of two independent xy-axis steering articulation zones that are run in series that allows the user the ability to perform leadless pacemaker implantation into both the septum and the apex within the right ventricle while also allowing the user the ability to cross the tricuspid valve safely and reliably. [0152] a) The embodiments for the distal articulation zone could comprise either an articulatable distal curve in a single direction via the handle (current design embodiment), an articulatable bi-directional distal curve via a handle actuator, or a shape-set distal curve with no articulation on the handle. [0153] b) The embodiments for this proximal articulation zone could comprise either an articulatable proximal curve via a handle actuator (current design embodiment), or a shape-set proximal curve with no articulation via a handle actuator. [0154] An inner non-steerable delivery catheter that is used to push the implant out of the implant protective cup for deployment and retract the implant back into the implant protective cup (re-sheathing) for repositioning and redeployment. [0155] A tether mechanism technology may be implemented. [0156] The means for the delivery catheter articulation zones to maintain their articulated positions when the user's hands are no longer touching the catheter handle. [0157] The ability for the user to re-sheathe the implant into the outer catheter's implant protective cup safely and reliably.
[0158] The ability for the user to re-sheathe, reposition and redeploy the implant within a newly chosen implantation site in either the septum or apex. [0159] The ability for the user to perform a mechanical tug test of the implant to assess tine fixation within the new implantation site prior to release of the implant and disengagement of the tether between the implant and catheter.
[0160] The concept associated with the present disclosure may provide a dedicated tool designed to safely and reliably navigate to and deploy a leadless pacemaker into either the septum or apex in the right ventricle. The concept associated with the present disclosure accomplishes this by utilizing two different articulation zones to steer the catheter in the xy-axis independently for safe and reliable crossing of the tricuspid valve and then navigation to either the mid/lower septum or the apex. The different dual zones may offer a user increased steering control and the ability to safely and reliably access the septum for deployment without manipulation or goose-necking of the catheter which may introduce excessive patient risks or harm. The distal articulation zone is designed to have a tight radius which can overcome difficult geometries present, especially in smaller Asian anatomies, which can hinder the ability for a single articulation curve to cross the tricuspid valve. Furthermore, it allows the user the ability to access the septum using this curve alone. If the user wishes to not deploy the implant into the septum, they can then utilize the proximal steering articulation curve to navigate to the apex for deployment.
[0161] The present disclosure may also incorporate and utilize a tether mechanism to maintain a connection to the implant until the user is sure that the implantation site location is acceptable, at which point they can safely release the tether and remove the catheter tooling.
[0162] If the user decides that the implantation site location is not acceptable, the present disclosure allows the user to safely and reliably re-sheathe the implant and reposition and redeploy it into a new location.
[0163] Another advantage of this present disclosure may include means to push the implant into the heart wall for maximum fixation mechanism engagement efficiency rather than rest the implant against the heart wall and retract the protective cup proximally which can lead to non-optimal fixation efficiency.
[0164] Another advantage of this present disclosure may include the ability for the user to remove their hand from the handle and maintain the steering position at all times, in addition the user has the means to manipulate the different steering articulation zones independently from each other.
[0165] The features disclosed in regard with the system (implantation catheter) may also apply to a method (e.g. for implanting an implant like a leadless pacemaker) and vice versa.
[0166] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teachings of the disclosure. The disclosed examples and embodiments are presented for purposes of illustration only. Other alternate embodiments may include some or all of the features disclosed herein. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention, which is to be given the full breadth thereof. Additionally, the disclosure of a range of values is a disclosure of every numerical value within that range, including the end points.
LIST OF REFERENCE NUMERALS
[0167] 1Leadless pacemaker device [0168] 10 Housing [0169] 100 Distal end [0170] 101 Proximal end [0171] 11 Electrode [0172] 12 Anchoring device [0173] 120 Anchoring member [0174] 13 Connection member [0175] 130 Opening [0176] 131 Shaft [0177] 132 Rounded face [0178] 133 Posts [0179] 2 Catheter device [0180] 20 Delivery catheter [0181] 200 Alignment device [0182] 201 Lumen [0183] 202 Flush port [0184] 203 Tether control [0185] 21 Tethering member [0186] 210 End [0187] 211 Positive-locking member [0188] 212 Tether portion [0189] 22 Adapter piece [0190] 220 Body [0191] 221 Retainer groove [0192] 222 Recess [0193] 223 Slanted face [0194] 23 Mandrel [0195] 230 Wire clamp [0196] 24 Steerable catheter [0197] 240 Straight shaft section [0198] 241 Proximal steering articulation zone [0199] 242 Connection section [0200] 243 Distal steering articulation zone [0201] 244 Protective cup [0202] 245 Guide lumen [0203] 246 Guide lumen [0204] 247 Flush port [0205] 25 Handle device [0206] 250-252 Actuation member [0207] 27 Steering device (pull wire) [0208] 260 Fixing location [0209] Steering device (pull wire) [0210] 270 Fixing location [0211] 28 Radiopaque element [0212] 3 Introducer device [0213] D Distal direction [0214] F Pulling force [0215] L Longitudinal axis [0216] L1, L2 Length [0217] LA Left atrium [0218] LV Left ventricle [0219] M Intra-cardiac tissue (myocardium) [0220] P Proximal direction [0221] R1, R2 Bending radius [0222] RA Right atrium [0223] RV Right ventricle [0224] TV Tricuspid valve