Recyclable thrombus filterTechnical field
The present invention relates to one kind filtering thrombus effect is good, positioning is repeated, fixing-stable, can extend Implantation Time canReclaim thrombus filter.
Background technology
At present, Deep vain thrombosis (deep venous thrombosis, DVT) and pulmonary thromboembolism (pulmonaryThromboembolism, PE) the incidence of disease increase day by day.As the complication of DVT most serious, PE has very high hairSick rate and fatal rate.Shown according to epidemiology survey in recent years, the only PE in U.S. year number of the infected is 750,000~900,000People, year, lethal number was 120,000~150,000.Pulmonary thromboembolism does not only have the high incidence of disease and fatal rate, and onset is hurried,Progress is rapid, and general pulmonary thromboembolism patient, which dies from, to fall ill in initial one hour, and pulmonary thromboembolism also results in chronic pulmonaryHigh pressure, has a strong impact on the quality of life of patient.
Lower limb DVT is to cause PE main reason, and document report shows that about 60%~70% lower limb DVT patient can send outRaw pulmonary thromboembolism.Research is it is also shown that 90%~95% pulmonary thrombosis embolus derives from lower limb DVT.General small bloodBolt embolus is difficult to cause pulmonary thromboembolism, only when Thromboembolus diameter is more than 7.5mm, can just Acute Pulmonary Embolism is endangeredMachine life.
Due to PE high incidence, high fatal rate and high disability rate, the concurrent PE of DVT how are prevented increasingly to be weighed by scholarDepending on.Generally acknowledged effective precautionary measures include strict bed rest, the anticoagulant therapy of system and the placement vena cave filter of DVT acute stages at presentDevice (vena cava filter, VCF).The anticoagulant therapy of system is considered as to treat the main side that DVT and prevention PE occurMethod, including treatment by Low molecule heparin and subsequent oral warfarin treatment.
But regular, system anticoagulant therapy is nor be perfectly safe and effectively.First, research shows, strictAnticoagulant therapy under, PE can occur again for the patient for still having up to 33%.Secondly, many DVT and/or PE cases are controlled for anti-freezingTreatment taboo (including:There are the wound or operation medical history person, have hemorrhagic apoplexy person, nervous centralis of height hemorrhage risk in the recent periodSystem tumor patient and have patient of hemorrhagic tendency and coagulation disorders etc.).Even if further, eliminating these high-risk bleedingsPatient, still have the incidence of 0.9%~7.9% severe haemorrhage complication during regular anticoagulant therapy.In addition, thoughLMWHs can apply to the women of gestation, but during oral neodicoumarin anticoagulant therapy, medicine can by placenta shadowRing the development of fetus.In these cases, placing VCF in inferior caval vein by interventional method just turns into uniquely arranging for prevention PEApply.
External large case retrospective analysis shows that PE can effectively be prevented by placing VCF, make DVT patient PE incidenceDrop to 0.9%~6% by 60%~70%, and lethal PE incidence is reduced to 0.7%~4%.VCF prevents PE curative effectsDefinitely, operation wound is small, simple to operate, complication is less, the method that the prevention PE of first choice is had been considered as at present.
VCF is a kind of with the apparatus of metal wire knitted or block of metal through laser engraving, is filled by special conveyingPut into inferior caval vein, form netted safeguard structure and stop thrombus larger in blood flow.These larger thrombus often also most holdEasily cause mortality PE.VCF is in itself to lower limb DVT without any therapeutic action, and significance of which is the larger bolt for preventing to come offSon blocks pulmonary artery and occurs PE.
VCF develops into today, experienced the first generation permanent VCF and second generation VCF.First generation VCF is permanent VCF.Filter once insert cannot adjustment position, can not take out.Permanent VCF lay for a long time brought safety issue byGradually cause concern, focus of attention concentrates on the displacement of filter, recurrent PE and inferior vena cava obstruction etc..Decousus is ground at randomStudy carefully discovery, filter is inserted rear PE in the recent period and reduced, but Deep vain thrombosis sends out PE situation showed increased again in 2 years,Being long placed at filter has thrombotic danger；If can not melt thrombus at filter, recent filter reduction PE effect will graduallyIt is cancelled.Obergassel etc. summarizes 26 documents totally 2646 permanent VCF of use patient, penetrates blood vessel up to 0~41%,Displacement is up to 0~26%, and thrombus occlusion is up to 0~30%, and observing time is longer, and complication is higher.There is invention CN101147705 to adoptImprove the performance on Nitinol surface with ceramic membrane, improve the biocompatibility of metal, promote endothelial cell quickly to climb attached, to dropLow its lures the formation of thrombus into.But permanent filter may cause patient to take anticoagulant all the life and trigger other complication.Therefore, the mid-80 has started recyclable VCF experimental study.
Second generation VCF includes recoverable version VCF and temporary VCF.The latter still lies in the conduit of percutaneous puncture after insertingOr on seal wire, take out after a certain time, the taking-up of filter is more convenient, but it has the disadvantage the risk in the presence of infection, and increase is wornInjury of vein, bleeding and thrombotic risk are pierced, makes troubles, has been rarely employed to patient's action.Recoverable version VCF canInternal filter is reclaimed through jugular vein or femoral vein by the method for intervention using special recovery system.If the state of an illness needsIt is left in place putting as permanent VCF, without replacing.Tide over a critical period such as patient, can be reclaimed if stable disease, so as to keep awayA series of complication that Preserving time is brought are exempted from.Research shows that recoverable version VCF and permanent VCF prevent pulmonary artery boltThe effect of plug is identical.Nadkami etc. is reported:Conventional recoverable version filter need to take out in 14 days, but Tempo filters have sixStill succeed the report taken out after week.Animal experiment proves that, filter can climb attached after inserting by vascular endothelial cell, occur endotheliumChange, this process was basically completed in 7~10 days, thus most scholars were advocated after recuperability VCF is inserted in 10 days at presentTaken out.
But in many cases, patient did not spent the critical days of DVT in 14 days.Need to place by VCF2~3 months are extended in the blood vessels, reach that medium-long term prevents the effect of pulmonary embolism.At present, can only be permanent stagnant by filterStay in human body.There is invention CN103031523 and CN103007361A to point out cytotoxic copper metal being plated in VCF tablesFace, plays and delays filter surface to be climbed attached speed by vascular endothelial cell.But the heavy metal long term toxicity of metallic copper can be to peopleBody produces serious adverse consequences, and lures that the secondary thrombus of filter surface is formed into, causes blood vessel blockage, and influence blood flow passes through.It is another to there is invention CN103027763A to delay on thrombus filter surface using the polymeric coating layer of endothelial cell growth is unfavorable forEndothelium is climbed attached.Equally, having cytotoxic polymeric coating layer, not only Human Umbilical Vein Endothelial Cells produce toxicity, while its toxicity can also be luredThe secondary thrombus of filter surface is formed, blood vessel blockage is caused, influence blood flow passes through.
In addition, the placement schematic diagram of the recyclable filter 1 largely used at present as shown in Figure 1 in the blood vessels.The filter 1 is putPut in the inferior caval vein between renal vein and iliac vein, prevent lower limb embolus up.The lower section of the filter 1 is that grid is largerNear-end net 2, is grid less distal end net 3 during top, and centre is connected by support bar 4.When being placed in inferior caval vein, anchor thorn 6Blood vessel is pierced into, plays a part of grappling, support bar is close to blood vessel endothelium.There is a recovering hook below near-end net, be used forReclaim the filter placed temporarily.Generally in the lower section of recovering hook, a nut is welded, for being threadedly coupled push rod.The filter 1 canAs recyclable and permanent apparatus, clinically substantial amounts of case has confirmed that its is evident in efficacy simultaneously, substantially reduces the wind of pulmonary embolismDanger.But, when making recyclable filter, it must be reclaimed being implanted into 14 days.If it exceeds 14 days, substantial amounts of endothelial tissue willLarge area covering support, resistance is big during recovery, easy injured blood vessel.The time window that filter is reclaimed is smaller, hinders recyclable filterA large amount of reagent applications., in addition, the nut for being generally used for connecting push rod uses stainless steel material, it is welded on NiTi conjunctionIn the filter tube of gold, in the presence of body fluid self-corrosion easily occurs for different materials.Corrosion product toxicity is big, is unfavorable for foreverStay for a long time in implant.
Preferable vena cava filter must include including following characteristics:1. secondary thrombus will not be caused to be formed, had wellBiocompatibility；2. the thrombus come off can be effectively captured, but does not influence venous return；3. can be safe and reliable to be fixed on cavity of resorption quietAstillen, it is not easily shifted；4. filter induction system caliber is thin, and releasing mechanism is simple；5. without ferromagnetism, magnetic resonance imaging is not influenceed；6. good mechanical stability, is unlikely to deform, is broken, falls apart；7. without severe complication；8. it can reclaim, or even can be in implantation 2~3It is recyclable after month.With updating for filter, some filters have possessed the most of feature of the above, but to so far, it is anyIt is preferable filter on a kind of filter is imponderable.These above-mentioned features can not be met simultaneously again.Therefore, comprehensive various chambers are quietThe advantage and disadvantage of arteries and veins filter, develop a kind of filter and easily insert；Thrombus efficiency high is captured without influenceing Inferior Vena Cava Blood Flow；And filterDevice can be fixed on inferior caval vein wall safely, it is often more important that can extend the recyclable vena cava filter of Implantation Time.
The content of the invention
It is an object of the invention to provide one kind filtering thrombus effect is good, positioning is repeated, fixing-stable, implantation can be extendedThe recyclable thrombus filter of time.
To achieve these goals, the technical scheme that provides of the present invention is：A kind of recyclable thrombus filter is provided, passed throughThe method of intervention is positioned over the inferior caval vein position between renal vein and iliac vein, prevents from being advanced into lung on Lower Limb Thrombosis, drawsPlay pulmonary embolism, it is characterised in that using two layers of screen pack design, including：Near-end net, distal end net and be connected to the near-end net andSupport bar between the net of distal end, the support bar is designed using inner concave shape, and the indent design includes female parts and is connected toThe proximal points and remote point of the upper and lower both sides of female parts, the proximal points and remote point play support close to blood vesselAnchor thorn is provided with blood vessel function, the proximal points, fixation is played, prevents filter generation position under the washing away of bloodMove.
The recyclable thrombus filter is integrally cut by laser shaping using Nitinol pipe.
Also include recovering hook, push rod and snare, the recovering hook is connected with the recyclable thrombus filter, and setThere is the breach coordinated with the snare, the distal end of the push rod sets the snare, and the snare is sheathed on the breach,The push rod and recovering hook are in hollow structure, and the push rod is built-in with latch lever, and the push rod penetrates described returnHook is received, until the marginal position of the near-end net, and the snare is locked in recovering hook.
The recyclable thrombus filter surface parcel PTFE films.
Each support bar is branched into two, and is designed using inner concave shape.
Compared with prior art, in recyclable thrombus filter of the invention, support bar using inner concave shape design, by apparatus withThe face contact of blood vessel endothelium is converted into a contact, greatly reduces the contact area of apparatus and blood vessel.And then delay endothelium groupKnit the time of covering support bar.In addition, inner concave shape is designed most support bar surface, away from blood vessel surface, is further addedBig endothelial cell climbs attached difficulty.In addition, proximal points and the effect of the multi-point support of remote point, can play stable filter in blood vesselThe effect of interior form.At the same time, PTFE films can be wrapped up in metal surface, to reduce the thrombus originality of apparatus in itself, and subtractedSlow endothelial cell climbs attached speed in equipment surfaces.Design more than, can extend the time of thrombus filter in the blood vesselsTo 2~3 months, the need for meeting clinical treatment.At the same time, by the implementation of the present invention, using on recovering hook and push rodSnare and latch lever design, it is to avoid different types of material is introduced on apparatus, it is to avoid filter occur self-corrosion and destroyThe mechanical performance and generation noxious material of apparatus so that filter of the present invention is more beneficial for extending the time window placed temporarily and useIn in Permanent implantation human body.
By following description and with reference to accompanying drawing, the present invention will become more fully apparent, and these accompanying drawings are used to explain the present inventionEmbodiment.
Brief description of the drawings
Fig. 1 is the schematic diagram of one embodiment of the thrombus filter of prior art.
Fig. 2 is the schematic diagram of one embodiment of recyclable thrombus filter of the invention in the blood vessels.
Fig. 3 is the front view of recyclable thrombus filter as shown in Figure 2.
Fig. 4 is the upward view of recyclable thrombus filter as shown in Figure 2.
Fig. 5 is the top view of recyclable thrombus filter as shown in Figure 2.
The schematic diagram for first state that the recyclable thrombus filter of Fig. 6 a present invention is freed with push rod.
The schematic diagram for second state that the recyclable thrombus filter of Fig. 6 b present invention is freed with push rod.
The schematic diagram for the 3rd state that the recyclable thrombus filter of Fig. 6 c present invention is freed with push rod.
Fig. 7 is the front view of second embodiment of recyclable thrombus filter of the invention.
Fig. 8 is the upward view of recyclable thrombus filter as shown in Figure 7.
Fig. 9 is the top view of recyclable thrombus filter as shown in Figure 7.
Figure 10 is the front view of the 3rd embodiment of recyclable thrombus filter of the invention.
Figure 11 is the upward view of recyclable thrombus filter as shown in Figure 10.
Figure 12 is the top view of recyclable thrombus filter as shown in Figure 10.
Embodiment
Element numbers similar in embodiments of the invention, accompanying drawing, which are described, with reference now to accompanying drawing represents similar element.
Embodiment 1：
As shown in Fig. 2,3,4 and 5, in the present embodiment, filter 1 is integrally cut by laser shaping using Nitinol pipe, itsThe Nitinol pipe used has diamagnetism, does not influence Magnetic resonance imaging.Filter is in integrally cage structure, and with poleGood mechanical stability, is unlikely to deform, is broken and falls apart, keep its structural intergrity.As shown in Fig. 2 involved in the present inventionRecyclable thrombus filter can be positioned over the position of inferior caval vein 7 between renal vein 9 and iliac vein 8 by the method for intervention, preventLung only is advanced on Lower Limb Thrombosis, causes pulmonary embolism.As shown in figure 3, using the design of two layers of screen pack, including near-endNet 2 and distal end net 3.The support bar 4 for connecting near-end net 2 and distal end net 3 is designed using inner concave shape.Support bar 4 curves inwardly, and is formedFemale parts 11, and two contact points up and down, including proximal points 12 and remote point 10.Filter of the present invention is being placed in the blood vesselsWhen, the arc of proximal points 12 and remote point 10 plays a part of support blood vessels close to blood vessel.The near-end of a plurality of support bar 4Point 12 and remote point 10 can play stable filter in the blood vessels in circumferencial direction formation multi-point support effect proximally and distallyThe effect of form.Anchor thorn 6 is provided with the position of proximal points 12, anchor thorn 6 stabs blood vessel, can played fixed obliquelyEffect, prevents filter to be subjected to displacement under the washing away of blood.Inner concave shape design is thoroughly by between support bar 4 and blood vesselFace contact is changed into a contact, greatly reduces the contact area of apparatus and blood vessel.Also endothelial tissue covering branch is delayed significantlyThe time of strut 4.The most surface of support bar 4 is caused away from blood vessel surface, further to increase endothelium in addition, inner concave shape is designedCell climbs attached difficulty.At the same time, PTFE films can be wrapped up in metal surface, to reduce the thrombus originality of apparatus in itself, andSlow down endothelial cell and climb attached speed in equipment surfaces.
As shown in Figure 6 a, recyclable thrombus filter recovering hook 5 of the invention is connected with push rod 15.In push rod 15Distal end is set on the breach 51 on a snare 14,14 sets of recovering hooks 5 of snare, and push rod 15 and recovering hook 5 are hollow structure, andThe push rod 15 is built-in with latch lever 13, and latch lever 13 is penetrated in the recovering hook of filter 1 inside push rod 15 up to near-endThe marginal position of net 2, snare 14 is locked in recovering hook, causes snare to be fixed in recovering hook, be will not fall off.
As shown in Figure 6 b, when pushing, push rod 15 applies active force in the near-end of filter 1, through conduit by filter 1It is pushed to inferior caval vein position.When reclaiming, the pulling force effect of snare 14 pulls filter 1 in conduit in recovering hook.Latch lever13 are locked in snare 14 on the recovering hook 5 of the near-end of filter 1 so that thrombus filter and the secure connection of push rod 15, will not take offFall.Filter 1 can be withdrawn when the placement location of filter 1 is not good in conduit, release and place again, untill success.
As fig. 6 c, after thrombus filter is placed into correct position, latch lever 13 is dropped back, 13 pairs of circles of latch lever are releasedThe limitation of 14 pairs of set, snare flicks rapidly, is freed with recovering hook and depart from filter 1.
Embodiment 2：
As shown in Fig. 7, Fig. 8 and Fig. 9, the recyclable thrombus filter provided in the present embodiment in the same manner as in Example 1, is usedNitinol pipe is integrally cut by laser shaping, and its Nitinol pipe used has diamagnetism, does not influence Magnetic resonance imaging.Its cage structure has fabulous mechanical stability, is unlikely to deform, is broken and falls apart, and keeps its structural intergrity.This example is carriedThe recyclable thrombus filter supplied can equally be positioned over the inferior caval vein 7 between renal vein 9 and iliac vein 8 by the method for interventionPosition, prevents from being advanced into lung on Lower Limb Thrombosis, causes pulmonary embolism.As shown in fig. 7, using the design of two layers of screen pack, whereinIncluding near-end net 2 and distal end net 3.The support bar 4 for connecting near-end net 2 and distal end net 3 is designed using inner concave shape.The bifurcated of support bar 4Into two, curved inwardly after opening, form female parts 11, and two contact points up and down, including proximal points 12 and remote point 10.The angle of the bifurcated of support bar 4 and interior curved degree are different with the size of support bar branch and different according to actual material property.When the recyclable thrombus filter that the present embodiment is provided is placed in the blood vessels, the arc of proximal points 12 and remote point 10 is close to blood vesselWall, plays a part of support blood vessels.The proximal points 12 and remote point 10 of a plurality of support bar 4 are in circumferencial direction shape proximally and distallyInto multi-point support effect, the form in the blood vessels of stable filter 1 can be played a part of.Anchor thorn is provided with the position of proximal points 126, anchor thorn 6 stabs blood vessel obliquely, can play fixed effect, prevent the generation position under the washing away of blood of filter 1Move.Face between support bar 4 and blood vessel endothelium thoroughly is contacted to be changed into by inner concave shape design a little to be contacted, and greatly reduces apparatus and bloodThe contact area of inside pipe wall.Also endothelial tissue is delayed to cover the time of support bar 4 significantly.In addition, inner concave shape, which is designed, causes big portionThe support bar surface divided is away from blood vessel surface, and further increase endothelial cell climbs attached difficulty.At the same time, can be in metal surfacePTFE films are wrapped up, attached speed is climbed in equipment surfaces to reduce the thrombus originality of apparatus in itself, and slow down endothelial cell.
Embodiment 3：
As shown in Figure 10, Figure 11 and Figure 12, on the basis of embodiment 1, a time similar with near-end is set in distal endHook 5 is received, two-way attachable characteristic is formed.During vena cava filter is implanted into, generally using through femoral vein or quiet through neckArteries and veins enters paths.In order to realize that a filter is applied to two approach requirements, in proximally and distally setting respectively for filter 1Two recovering hooks 5, for being connected with push rod 15.Two paths of femoral vein and jugular vein can be used when also realizing and reclaiming.
Above disclosed is only the preferred embodiments of the present invention, can not limit the right of the present invention with this certainlyScope, therefore the equivalent variations made according to scope of the present invention patent, still belong to the scope that the present invention is covered.