Blood vessel blocking spiral device

Abstract

A blood vessel blocking spiral device comprises an air inflation device and a pinch-off device connected with the air inflation device. The pinch-off device comprises a spiral guide wire and a strip-shaped inflatable air bag attached to the spiral guide wire, and an annular strip-shaped contact surface is formed after the air bag is inflated; in each spiral of the spiral guide wire, the diameter of each circle is 2.5-3.0 cm, and the distance between every two circles is 0.5-1.5 cm. And the strip-shaped inflatable air bag and the guide wire are arranged in parallel or annularly wound on the guide wire.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a vascular occlusion spiral device. Background Technology

[0002] In partial nephrectomy and other surgical procedures involving clamping of major blood vessels (renal artery, abdominal aorta, inferior vena cava, lower segment of thoracic aorta, and common iliac artery), the renal artery or other major blood vessels need to be dissected and clamped to block blood flow, allowing the surgeon to perform the necessary operations. These major blood vessel surgical procedures can be applied in the following scenarios: 1. Partial nephrectomy; 2. Open repair of abdominal aortic aneurysm; 3. Removal of inferior vena cava tumor thrombus; 4. Traumatic repair of abdominal aortic rupture; 5. Thoracic aortic aneurysm resection; 6. Traumatic repair of iliac artery rupture; 7. Devascularization for portal hypertension, etc. The diameter of the human aorta and main vein is 1-2.5 cm; during the above surgeries, the aorta and main vein need to be dissected and exposed for 1-3 cm.

[0003] Currently, the commonly used temporary vascular occlusion methods mainly include: The vascular clamping method. This method blocks blood flow by clamping the wall of an artery or vein with vascular clamps. However, this method suffers from uncontrollable clamping pressure, a small clamping area, and uneven force distribution, which can easily damage the outer wall of the vessel, worsen adhesions in nearby tissues, and lead to damage to the inner wall of the vessel, resulting in impaired blood flow and thrombosis. Furthermore, the vascular clamp's location in the surgical area can hinder further surgical procedures.

[0004] The ligation method involves surgically dissecting the blood vessel, threading a ligation suture or occlusion band through the bottom of the vessel, and then lifting both ends of the ligation suture to form a tightening loop around the vessel to block blood flow. However, this method also lacks precise control over the occlusion pressure, and because the ligation suture or occlusion band is relatively thin, excessive pressure after tightening can easily cut the vessel. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides an innovative, easy-to-operate, controllable vessel occlusion spiral device with arbitrarily controllable vessel length and occlusion force, uniform occlusion force, and the ability to freely change shape according to the vessel's course. It can form several spiral-shaped contraction loops to block blood vessels.

[0006] To achieve the above objectives, the reversible vascular occlusion spiral device provided by the present invention is implemented as follows: A vascular occlusion spiral device includes an inflation device and a clamping device connected to the inflation device; The clamping device includes a spiral guide wire and a strip-shaped inflatable air bladder attached to the spiral guide wire, which forms a circumferential strip-shaped contact surface after inflation; In each spiral guidewire, the diameter of each turn is 2.5-3.0 cm, and the spacing between each turn is 0.5-1.5 cm; The guidewire has a diameter of 1 mm, and the strip-shaped balloon has a diameter of 5 mm.

[0007] The strip-shaped inflatable airbag and guidewire are arranged side by side or wrapped in a ring around the guidewire.

[0008] Furthermore, production / assembly constraints should be noted: to avoid adjacent rings colliding with each other, a safe gap must be maintained between adjacent rings (0.1–0.2 cm is recommended); if the airbag's inflated width is ≥0.5 cm, the spacing between each ring can start from 0.60 / 0.75 cm.

[0009] Furthermore, when it is necessary to ensure that at least two loops of the balloon / guidewire are wrapped around the exposed blood vessel each time, according to N (number of loops) ≈ L (exposed blood vessel length) / p (pitch), for N ≥ 2, p must ≤ L / 2. In this case, the following optimal values ​​are made: When the exposed length of the blood vessel to be blocked is 1.0-1.2, 1.3-1.8, 1.9-2.3, 2.4-2.9, or 3.0 cm, the corresponding spacing between each loop is ≤0.5-0.6, ≤0.65-0.9, ≤0.95-1.15, ≤1.2-1.45, or ≤1.5 cm, respectively.

[0010] Furthermore, When the outer diameter of the blood vessel to be blocked is 1.0-1.4, 1.5-1.9, 2.0-2.2, or 2.3-2.5 cm, the corresponding diameter of each loop is 2.5, 2.5, 3.0, or 3.0 cm, and the corresponding radial clearance is 0.55-0.75, 0.3-0.5, 0.4-0.5, or 0.25-0.35 cm.

[0011] Calculation basis: Dv: outer diameter of blood vessel (1–2.5 cm); Dc: Diameter per turn of the spiral; p: pitch; δ: Fit / Rebound Margin / Radial Clearance, ranging from 0.2 to 0.75 cm. The maximum diameter of the airbag strip after inflation refers to its maximum radial thickness h; Minimum radial thickness required: e≥(Dc−Dv) / 2+δ; Therefore, h ≥ e must be true. Furthermore, select the guide wire diameter d based on the coil diameter, using empirical values ​​(ensuring it can be screwed in but is not easily deformed): The target wire diameter ratio C = Dc(mm) / d ≈ 15-22. Therefore: When the diameter of each loop is 2.5 or 3.0 cm, the fit / rebound margin is 0.2–0.3 cm, and the guide wire diameter is 1.3–1.6 or 1.5–1.8 mm, preferably 1.4 or 1.6 mm.

[0012] Similarly, when the diameter of each ring is 2.5 or 3.0 cm, the fit / rebound margin is 0.2–0.3 cm, and the maximum diameter of the airbag strip after inflation is 8.5-11 or 8-9 mm.

[0013] Furthermore, the cross-section of the airbag can be semi-circular, square, or oval, and a thickened rib can be set at the highest point of the airbag cross-section along the length of the guide wire.

[0014] Furthermore, after the airbag is inflated, the width of its cross-section decreases by 0.5 times every 1cm along the length direction, and then returns to its original width after 1cm along the length direction to prevent overinflation.

[0015] Furthermore, a pressure valve is installed at the rear of the inflatable airbag, which inflates the airbag during the inflation phase and provides precise pressure regulation. The pressure measuring valve mainly addresses the issue of uncontrollable pressure.

[0016] Working principle The helical geometry provides self-centering and sequential insertion during the spiral insertion process; the inflatable balloon strip forms a wide-band circumferential pressure (this structure is crucial; the thickened ribs help the balloon to form only a flat, wide band after inflation, thus creating a circumferential / planar pressure on the blood vessel, rather than a pure circular arc cross-section, resulting in point or linear pressure), reducing point pressure and shear; the locking valve maintains the target pressure / volume, achieving reversible external occlusion. The guidewire is flexible and, after rotation, gradually becomes parallel to the direction of blood vessel formation and wraps around the outer surface of the blood vessel.

[0017] The spiral guidewire is surrounded by an inflatable balloon. By rotating the guidewire, utilizing its spiral structure, the subsequent portion of the guidewire wraps around the blood vessel, forming an initial encapsulation. The inflatable balloon surrounding the spiral guidewire is inflated by a connected valve; gas enters through a pressure valve and inflates the balloon. The inflated spiral balloon tightly encircles the blood vessel, and the pressure from the balloon's expansion achieves vascular occlusion. Releasing the pressure valve releases the gas from the balloon, relieving pressure and restoring blood flow.

[0018] The spiral guidewire, as the main structure of the device, has a unique spiral shape and is made of a material with good flexibility and biocompatibility, allowing it to adapt to the complex internal environment of blood vessels without causing additional damage. Its main advantages are: 1. Due to its spiral shape, it can be manually manipulated to control the length of the blood vessel being wound (i.e., the length of the blood vessel to be blocked); 2. Because the length of the blocked blood vessel is controllable, it is suitable for more vascular scenarios and is more adaptable to the patient's vascular condition; 3. Due to its spiral shape, the pressure from balloon inflation on the blood vessel is more even, resulting in less damage to the vessel; 4. Due to its spiral shape, the blood flow blocking effect is better. Compared to the cross-sectional blocking of hemostatic forceps or tourniquets, the spiral shape is more like a spatial blocking. Therefore, less pressure can produce a better blocking effect, further reducing damage to the blood vessel.

[0019] The inflatable airbag is tightly wrapped around the spiral guide wire. The airbag has high elasticity and good airtightness, and expands evenly without leaking air during the inflation process. Because this invention employs a structure in which a spiral guide wire is wrapped around an inflatable airbag, the following beneficial effects can be achieved: Flexibility in occlusion length and force: Because the spiral guidewire can be rotated to increase or decrease the length around the blood vessel, occlusion of any length can be achieved. Simultaneously, the occlusion force can be arbitrarily adjusted by precisely controlling the balloon inflation pressure through a pressure valve, meeting the diverse needs of different surgical scenarios for vascular occlusion.

[0020] Low vascular damage: The present invention forms several contraction rings to block blood vessels, and the pressure distribution is uniform. Compared with traditional blocking methods, the pressure is lower, which greatly reduces the risk of damage to the intima, media and adventitia of blood vessels, which is conducive to the rapid recovery of vascular function after surgery and reduces the occurrence of complications.

[0021] Morphological adaptability: The combination of spiral guidewire and inflatable balloon can freely change shape according to the course of blood vessels. Whether it is a straight blood vessel segment or a complex shape such as a tortuous or bifurcated blood vessel, it can closely fit and achieve effective blockage, which improves the applicability of the device under different vascular anatomy structures.

[0022] Reversibility: Blood flow can be restored by simply releasing the pressure valve, and the restoration process has minimal secondary impact on the blood vessels, ensuring the integrity of vascular function and providing a safe, reliable and reversible vascular occlusion solution for clinical surgery. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a spiral guidewire being tilted and rotated into a blood vessel.

[0024] Figure 2 This refers to the guidewire, airbag, and its cross-section.

[0025] Figure 3 This is a schematic diagram showing the final wrapping of the spiral guidewire around the blood vessel. Detailed Implementation

[0026] See Figure 1-3 A vascular occlusion spiral device includes an inflation device and a clamping device connected to the inflation device; The clamping device includes a spiral guide wire 11 and a strip-shaped inflatable airbag 12 attached to the spiral guide wire, which forms a circumferential strip-shaped contact surface after inflation. In each spiral guidewire, the diameter of each turn is 2-3.5 cm, and the spacing between each turn is 0.5-1.5 cm; The guidewire has a diameter of 1 mm, and the strip-shaped balloon has a diameter of 5 mm.

[0027] A strip-shaped inflatable airbag 12 and a guide wire 11 are arranged side by side or wrapped around the guide wire 11.

[0028] Materials and Surface Treatment Guide wire: Nickel-titanium superelastic alloy wire (outer diameter matches coil diameter), with a hydrophilic / low friction coefficient coating on the surface.

[0029] Airbag: TPU / nylon composite film or Pebax-like material, thickness designed according to rated pressure; laser welding / thermo-bonding or micro-sleeve + adhesive composite is used to bond it to the guidewire.

[0030] Piping: Medical-grade flexible tubing with Luer lock connector.

[0031] Manufacturing and assembly Spiral forming: The winding fixture controls the coil diameter and pitch; heat setting ensures consistent springback.

[0032] Airbag strip forming: extrusion / blown film / hot pressing to seal the edges to form a narrow strip-shaped cavity; thickness limiting ribs are set to limit radial bulging or to form point-like or linear pressure in the radial direction.

[0033] Assembly: Attach, wrap, or weld along the spiral axis, ensuring a rounded transition at the leading edge of the airbag strip (R≥0.2cm). After completion, perform sealing / burst / fatigue tests (type tests).

[0034] 1. Preoperative preparation and positioning Accurately locate the target blood vessel 2 under the surgical field of view, ensure sufficient operating space around the blood vessel 2, gently place the guide wire end of the spiral device close to the blood wall, and ensure the balloon is fully deflated.

[0035] Visual and connectivity checks were performed to confirm that there were no burrs or cracks on the outer edge of the guide wire spiral and the surface of the airbag; the inflation tubing was securely connected.

[0036] Venting and sealing test: Fill the tubing and airbag with physiological saline (or saline / contrast agent 1:1 for visualization test), slowly pressurize to the rated test pressure specified in the instructions; hold for 30–60 s, and completely vent after there is no leakage.

[0037] Lubrication and anti-sticking: A small amount of sterile saline is applied to the outer surface of the spiral and the air bladder to reduce friction when in contact with tissue.

[0038] Direction confirmation: Confirm the chirality of the helix (right-hand or left-hand). The subsequent tightening direction should be consistent with the chirality (right-hand → clockwise, left-hand → counterclockwise).

[0039] 2. Spiral + Winding Process Measurement: Measure the outer diameter Dv of the exposed target blood vessel segment 2.

[0040] Matching: Select or fine-tune the diameter Dc of the spiral coil so that it is slightly larger than the outer diameter of the blood vessel 2 (recommended difference ΔD=0.3–0.8cm) so that after insertion, there is a slight fit without compression before inflation.

[0041] Coverage length: Based on the planned blocking length, it is generally wrapped more than 2 times, N≈L / p, where p is the spacing between the turns (0.5–1.5cm). Usually, an extra 0.5–1 turn is reserved to prevent displacement.

[0042] Objective: By rotating in a helical chiral direction and gently advancing axially, the target blood vessel 2 is gradually introduced into the helical cavity, achieving circumferential coverage rather than shearing and compression.

[0043] Alignment and entry angle Make the spiral axis approximately parallel to the axis of blood vessel 2, and the front end form an inclination angle of 10–20° with the blood vessel.

[0044] Align the first opening with the proximal end (or distal end, as needed) of the planned blocking segment, and confirm that the leading edge chamfer of the airbag strip is smooth.

[0045] Import first lap With extremely low thrust, place the outer edge of the first loop against the surface of blood vessel 2, and begin continuous rotation at small angles (30–60° each time), while advancing very gently (<1–2 mm / second).

[0046] When the first rotation passes the point of the vessel's maximum outer diameter, the vessel naturally falls into the spiral lumen; at this point, stop the axial thrust and only maintain a small rotation to keep the vessel and spiral coaxial.

[0047] Looping in Rotate at a constant speed in the chiral direction (a slow, gentle motion of 30–60 ° / s is recommended), with minimal feed that matches the pitch, so that the second and third turns pass over the blood vessel in sequence and complete the encapsulation.

[0048] Monitoring: There should only be a sliding-adhesion sensation between the spiral and the blood vessel, without any "jumping / blocking". If blockage occurs, retreat 30–90°, fine-tune the entry angle, and then proceed.

[0049] Confirmation of coverage length and number of loops When the coverage length reaches the estimated number of loops, stop forward feeding and only make a slight angle return (±15–30°) to allow each loop to automatically align with the surface of the blood vessel.

[0050] 3. Inflation blocking process Principle: Gradual inflation—observe fit—fine-tune angle—lock. All pressure / volume limits are based on the design verification values ​​of this device.

[0051] Pre-charge and calibration Slowly pre-charge a small amount (e.g., 10–20% of the rated volume) to change the balloon strip from a “strip” shape to a “crescent / ring” shape and make initial contact with the outer wall of the blood vessel.

[0052] Gently swing the belt back and forth by ±15–30° to ensure even contact and avoid localized bulging.

[0053] Gradual pressurization Inflate in small increments (e.g., 5–10% of the rated volume per step).

[0054] Pause for 5–10 seconds at each step and observe three points: a) Whether the circumferential adhesion of the spiral-vascular interface is continuous; b) Has axial slippage occurred? (If so, fine-tighten and tighten 10–30° to compensate). c) Assess "increased flow resistance" based on visual inspection or ultrasonic testing.

[0055] To achieve blocking and locking When the set "blocking criterion" is met, the check valve / lock valve is closed.

[0056] Record: final inflation volume / pressure, effective number of revolutions.

[0057] Fixing and preventing displacement If long-term retention is required, use the included limiting clips / suture lugs to connect to the surrounding tissue or fixation plate near the end of the spiral device to prevent loosening caused by external pulling.

[0058] 4. Deactivation and Withdrawal Slowly deflate the balloon until it completely collapses, and confirm that the circumferential rebound is sufficient and there are no adhesion points between the device and the blood vessel.

[0059] Retract at the same speed in the opposite direction (30–60° each time), minimizing axial pull; if slight jamming occurs, swing back 15–30° in the forward direction before retracting in the reverse direction.

[0060] The external verification device was intact and free of residual debris; the time taken for withdrawal was recorded.

[0061] Precautions Contact pressure distribution: prioritize broadband contact rather than line contact with the airbag strip; if necessary, thickness limiting ribs can be set on the back of the airbag strip to limit local overfilling.

[0062] Anti-slip mechanism: When covering short sections (1–2 cm), it is recommended to "re-tighten the final angle by 10–30°" and add 0.25–0.5 turns for redundancy.

[0063] Surface engineering: It is recommended that the outer surface of the spiral and airbag strip be coated with a hydrophilic coating or microtextured to reduce friction and prevent slippage.

[0064] Visualization: Add visual traces (such as contrast agents / color markers) inside the airbag strip to check inflation uniformity.

[0065] Upper limit control: The inflation pressure and volume must not exceed the rated upper limit of the device to avoid excessive circumferential compressive stress on the outer wall of the blood vessel.

Claims

1. A vascular occlusion spiral device, characterized in that: Includes an inflation device and a clamping device connecting the inflation device; The clamping device includes a spiral guide wire and a strip-shaped inflatable air bladder attached to the spiral guide wire, which forms a spiral strip-shaped contact surface after inflation. In each spiral guidewire, the diameter of each spiral is 2.5-3.0 cm, and the spacing between each spiral is 0.5-1.5 cm; The strip-shaped inflatable airbag and guidewire are arranged side by side or wrapped in a ring around the guidewire, and the two are welded or bonded together.

2. The vascular occlusion spiral device as described in claim 1, characterized in that: When the outer diameter of the blood vessel to be blocked is 1.0-1.4, 1.5-1.9, 2.0-2.2, or 2.3-2.5 cm, the corresponding diameter of each spiral is 2.5, 2.5, 3.0, or 3.0 cm, and the corresponding radial clearance is 0.55-0.75, 0.3-0.5, 0.4-0.5, or 0.25-0.35 cm.

3. The vascular occlusion spiral device as described in claim 1, characterized in that: When it is necessary to ensure that at least two loops of balloon / guidewire are wrapped around the exposed blood vessel each time, the following preferred values ​​are made: when the exposed length of the blood vessel to be blocked is 1.0-1.2, 1.3-1.8, 1.9-2.3, 2.4-2.9, or 3.0 cm, the corresponding pitch of each spiral is ≤0.5-0.6, ≤0.65-0.9, ≤0.95-1.15, ≤1.2-1.45, or ≤1.5 cm.

4. The vascular occlusion spiral device as described in claim 1, characterized in that: If the width of the airbag is ≥0.5cm after inflation, the spacing between each spiral should start from 0.60 / 0.75cm.

5. The vascular occlusion spiral device as described in claim 1, characterized in that: When the diameter of each spiral is 2.5 or 3.0 cm, the fit / rebound margin is 0.2–0.3 cm, and the guide wire diameter is 1.3–1.6 or 1.5–1.8 mm, preferably 1.4 or 1.6 mm.

6. The vascular occlusion spiral device as described in claim 1, characterized in that: When the diameter of each spiral is 2.5 or 3.0 cm, the fit / rebound margin is 0.2–0.3 cm, and the maximum diameter of the airbag strip after inflation is 8.5-11 or 8-9 mm.

7. The vascular occlusion spiral device as described in claim 1, characterized in that: The cross-section of the airbag can be semi-circular, square, or oval. At the highest point of the airbag cross-section, a thickened rib is set along the length of the guide wire.

8. The vascular occlusion spiral device as described in claim 1, characterized in that: After the airbag is inflated, the width of its cross-section decreases to 0.5 times its original size every 1cm along the length direction, and then returns to its original width after 1cm along the length direction, to prevent overinflation.

9. The vascular occlusion spiral device as described in claim 1, characterized in that: It is also equipped with a pressure valve connected to the rear of the inflatable airbag, which can inflate the airbag during the inflation phase and has a precise pressure regulation function.

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