Intravascular stent is degraded and fatigue property test bioreactor and its test method
Technical field
The invention belongs to the field of medical instrument technology, and in particular to a kind of intravascular stent degraded and fatigue property test life
Thing reactor and its test method.
Background technology
Coronary atherosclerosis can cause lumen of vessels stenosis or occlusion, cause myocardial ischemia, anoxic or necrosis and cause
Heart disease, i.e., " coronary heart disease ".It is the disease that endangers people's life and health most serious that cardiovascular and cerebrovascular disease is known as by the whole world
The morbidity and mortality of one of disease, wherein coronary heart disease are occupied first of various diseases.Intravascular stent implantation is treatment coronary heart disease one
A effective and universal method.
With the fast development of science and technology, intravascular stent mainly experienced bare metal stent, carried stent and degradable
The evolution of stent.The mechanical support for the stent that narrow blood vessel needs during restoration, although bare metal stent and load medicine branch
Frame has excellent mechanic properties, but after vascular morphology recovers, the presence of stent can cause reangiostenosis to show
As, while there is likely to be some potential complication.Biodegradable stent can not only provide mechanic properties for blood vessel, and
The material harmless to itself is degraded into, avoids the appearance of thrombus and the generation of restenosis.The stent military service stage bears periodically
Pulsating load, its fatigue behaviour determine its military service effect.Biodegradable stent is directed to, its mechanical property changes with palliating degradation degree
And constantly change, its degradation property influences its performance.
The simulation of blood vessel vivo environment is directed to, existing one kind is to be used as pulsation source by peristaltic pump, passes through pressure regulator valve
Adjust and change the maximum pressure that blood vessel sample is born.Another proposes a kind of Weave type artificial blood vessel fatigue performance bionic
Test device and its test method, test the fatigue durability of blood vessel, produce Pulsating Flow using peristaltic pump, pass through current limliting
Device adjusts the maximum pressure at artificial blood vessel.The third proposes a kind of blood blood flow characteristic towards the design of intravascular stent mechanism
Test device, tests the fluid dynamics compatibility under different flow characteristic curve of intravascular stent.Stent is in pulse wave
Under the action of degrade, blood flow and pulsating pressure the cyclic load joint effect of stent degraded and the fatigue behaviour of stent.
Pulsation source control and circuit control simulation Pulsating Flow effect, pulsation source control is respectively adopted in the design principle of apparatus above
System uses peristaltic pump, and Pulsating Flow is controlled with the use of pressure regulator valve;Circuit control produces pulsation using the real-time aperture regulation of proportioning valve
Stream.Functional effect:It is approximately SIN function that flow and pressure, which change over time, flow Qt=(A sin (ω t)+A)+Qm(QtFor
Certain moment flow;Δ Q=2A is difference in flow;QmFor regime flow, average discharge), pressure Pt=(B sin (ω
t)+B)+Pm(PtFor certain moment pressure;Δ P=2B is pulse pressure, PmTo stablize pulse pressure, average pulse pressure), the above
The pulsation source that device uses cannot adjust average discharge at the same timeStablize pulse pressure PmWith pulse pressure Δ P, SIN function is caused to adjust
It can not meet test request;Ripple frequency increase, due to the hysteresis quality of circuit low pressure, can make when circuit low pressure does not reach predetermined value
When started the pulsating cyclic in next cycle, it is impossible to meet the pressure requirement of corrosion test, therefore apparatus above cannot simulate height
The lower accelerated corrosion test of frequency;Apparatus above is tested only in single stent, it is impossible to while realize multichannel flow and pressure
The independent adjusting of powerful feature.Therefore, though apparatus above can produce Pulsating Flow, stent cannot be met to pulse pressure, stable arteries and veins
The cooperation requirement of pressure and average discharge, and can not achieve that multichannel is separately adjustable and high frequency under test request.
The content of the invention
In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is that provide a kind of intravascular stent
Degraded and fatigue property test bioreactor and its test method, using pulsation source control loop, pulsation source is by peristaltic pump
With the mode of metering parallel connection of pumps, throttle valve is coordinated to complete the control of circuit Pulsating Flow.
The present invention uses following technical scheme:
Intravascular stent is degraded and fatigue property test bioreactor, it is characterised in that including biological fermentation tank, biology
The first entrance of fermentation tank by pipeline successively with culture chamber, the first return circuit testing device, the first four-way valve and the second triple valve
Connection, the first return circuit testing device are connected by pipeline with the first exit end of the first four-way valve, the input end of the first four-way valve
Connected with the second triple valve port of export, two input ends of the second triple valve pass through pipeline and the second metering pump and peristaltic pump respectively
Port of export connection, the input end of the second metering pump and peristaltic pump respectively by the first exit end of pipeline and the second four-way valve and
Second outlet end connects, and the input end of the second four-way valve is connected by the port of export of pipeline and biological fermentation tank, is set in culture chamber
Replacement vessels are equipped with, the both ends of replacement vessels are connected with biological fermentation tank and the first return circuit testing device respectively, in blood vessel
Substitute is internally provided with intravascular stent.
Specifically, culture chamber is also connected by pipeline with the port of export of the first metering pump, in culture chamber and the first metering pump
Between pipeline on be disposed with second servo loop test device and the first triple valve, the port of export of the first triple valve and second time
The connection of road test device, the first input end of the first triple valve are connected with the port of export of the first metering pump, and the of the first triple valve
Two input ends are connected by pipeline with the second outlet end of the first four-way valve, the first metering pump input end pipeline and the second four-way valve
The connection of the 3rd port of export, the port of export of the input end piping of the second four-way valve and biological fermentation tank connects, and passes through the first meter
The cooperation of amount pump and the second metering pump is used for the accelerated corrosion testing fatigue requirement under high frequency.
Further, the 3rd port of export of the first four-way valve is connected by pipeline with Back flow bottle, in the first four-way valve and is returned
Pressure gauge and counterbalance valve are disposed with pipeline between liquid bottle, filter is provided with Back flow bottle.
Further, culture chamber is connected by the second entrance of pipeline and biological fermentation tank, culture chamber and biological fermentation tank
Between pipeline on be provided with the 3rd throttle valve, pipeline uses Pulsating Flow pipeline.
Further, the first return circuit testing device and second servo loop test device include flowmeter, and flowmeter connects successively
Pressure transmitter and shut-off valve are connected to, flowmeter and pressure transmitter are connected with recorder respectively, for recording blood vessel branch in real time
The pressure change and changes in flow rate of frame entrance.
Specifically, replacement vessels are made of transparent material, compliance is 3%~5%, including multiple, is arranged at intervals
In culture chamber, the first entrance of biological fermentation tank is connected to the port of export of the first multiple-pass joint by pipeline, is connected first more
The arrival end of head divides multichannel, and a replacement vessels, each replacement vessels are connected by a first throttle valve respectively per road
The other end multichannel of the second multiple-pass joint is connected to by first return circuit testing device and a second throttle respectively
The port of export, the second multiple-pass joint arrival end is connected to the first input end of the first four-way valve, for producing the wriggling of stable pulse pressure
Pump and the Pulsating Flow ring that offer is provided and stablizes pulse pressure and pulse pressure and can adjust alone for producing the second metering pump of pulse pressure
It is separately adjustable that border, cooperation first throttle valve and second throttle are used for realization multichannel.
Specifically, each replacement vessels are fixed in culture chamber by blood vessel clamper, blood vessel clamper is using transparent
Material is made, including clamper shell, and clamper shell forms cylindrical structure by four arc sections, is internally provided with thrombus replacement
Thing, by varying the degradation characteristic of intravascular stent under the curvature simulation different curvature of clamper shell.
Further, the external part of four arc sections coordinates in horizontally and vertically direction respectively by bolt, second two-by-two
Gasket and nut are fastenedly connected, and each bolt is provided with the first gasket with arc section external part junction, are padded in bolt and first
Spring is provided between piece, for meeting the radial dilatation requirement of intravascular stent.
Specifically, the upper and lower surface of culture chamber is made of poly (methyl methacrylate) plate, replaced in the interior parallel of culture chamber in blood vessel
Thing cross section is provided with the measuring apparatus of diameter for recording diameter change.
The invention also discloses a kind of degraded of intravascular stent and the test method of fatigue property test bioreactor, bag
Include the Steady flow tests and radial direction fatigue that the degradation property separately adjustable for multichannel under high frequency is tested, multichannel is separately adjustable
Test;
The degradation property test that multichannel is separately adjustable under high frequency:When peristaltic pump, the first metering pump, the second metering pump at the same time
In running order, the liquid for flowing through peristaltic pump and the second metering pump flows into intravascular stent, flows through the liquid flow of the first metering pump
Enter culture chamber, the pressure and flow tune of different passage independences can be realized by the synergic adjustment of first throttle valve and second throttle
Section, is coordinated by the first metering pump, the second metering pump phase and performance test requirement of degrading under high frequency can be achieved;
The separately adjustable Steady flow tests of multichannel:When peristaltic pump is in running order, liquid flows into blood by peristaltic pump
Pipe holder, adjusts second throttle and first throttle valve opening, realizes the Steady flow tests that multichannel Independent fluxes are adjusted;
Radial direction testing fatigue:When peristaltic pump and the second metering pump are in running order, the first four-way valve and the two or four is adjusted
Port valve, makes liquid in biological fermentation tank sequentially flow through peristaltic pump, the second metering pump, the second triple valve, the first four-way valve, the one or three
Port valve, culture chamber and the 3rd throttle valve, the 3rd throttle valve opening and peristaltic pump are adjusted by observation of the measuring apparatus of diameter to diameter
With the discharge characteristic of the second metering pump, diameter change is set to meet test request.
Compared with prior art, the present invention at least has the advantages that:
Intravascular stent degraded of the present invention and fatigue property test bioreactor, by Pulsating Flow pipeline successively by biology
Fermentation tank, first throttle valve, culture chamber, the first return circuit testing device, second throttle, peristaltic pump, metering pump connection, using meter
Amount pump and peristaltic pump provide Pulsating Flow for the external degradation experiment of intravascular stent and testing fatigue, and being used cooperatively by throttle valve to divide
Flow and pressure at not separately adjustable different branch intravascular stent, can be realized by peristaltic pump and being used cooperatively for metering pump
Accelerated degradation performance test under high frequency, is provided closer to internal fluid environment using biological fermentation tank for intravascular stent, so that
Realize intravascular stent external degradation and fatigue property test under different blood pressure pulsations characteristics and flow.
Further, culture chamber connects the first metering pump by second servo loop test device, to being carried out outside intravascular stent
Extruding, coordinates expansion of the second metering pump and peristaltic pump in the first circuit to internal stent, solves low pressure hysteresis under high frequency and asks
Topic, meets under high frequency to the test request of pressure.
Further, culture chamber upper and lower surface, blood vessel fixture and replacement vessels are made of transparent material, can be real-time
Observe degraded and the fatigue conditions of intravascular stent.
Further, four arc sections of blood vessel clamper fit through two-by-two is bolted, and sets spring, it can be achieved that blood
Test of the pipe holder under different curvature, and the radial dilatation of stent is not influenced.
Further, nondestructive measurement is realized in outside diameter change of the measuring apparatus of diameter to replacement vessels, and flowmeter and pressure become
Device is sent to test respectively flow and pressure, so as to instruct circuit pressures and flow-rate adjustment.
The invention also discloses a kind of degraded of intravascular stent and the test method of fatigue property test bioreactor, bag
Include the Steady flow tests and radial direction fatigue that the degradation property separately adjustable for multichannel under high frequency is tested, multichannel is separately adjustable
Test;Wherein, the degradation property test that multichannel is separately adjustable under high frequency passes through peristaltic pump, the second metering pump, first throttle valve
With being used cooperatively for second throttle, pressure and flow that can be at separately adjustable different branch intravascular stent:Pressed at intravascular stent
The strong superposition for being 0~120mmHg of pulse pressure and stablizing pulse pressure (75mmHg~120mmHg), by varying the second motors of metering pumps
Rotating speed and stroke adjust pulse pressure frequency (1.2~36Hz) and size respectively, meet the blood vessel that compliance requires (3%~5%)
Fluid pressure is converted to diameter change by substitute, and peristaltic pump and throttle valve, which coordinate, adjusts fluid stable pulse pressure, by stablizing arteries and veins
The adjusting of pressure and pulse pressure meets requirement of the stent to pressure;Average discharge (200ml/min~250ml/ at intravascular stent
Min it is) the second metering pump and the flow summation of peristaltic pump, cooperates with the adjusting of pressure, flow is met test request, and pass through section
That flows valve is used cooperatively the separately adjustable of achievable branch pressure flow, and the first metering pump and the second metering pump are used cooperatively can be real
Existing high frequency accelerated degradation test, realizes the test of intravascular stent degradation property under fluid shear stress and radial pulsation expansion, is
Intravascular stent degraded provides more real blood flow characteristic;The separately adjustable Steady flow tests of multichannel:The use of peristaltic pump is branch
Frame test provides steady motion of a fluid environment (200ml/min~250ml/min), adjusts wriggling pump discharge, coordinates first throttle valve and the
Two throttle valve openings are adjusted, and are completed each branch stent in different fluid shearing stress and are stablized the Steady flow tests under pulse pressure.Radially
Testing fatigue:It is connected after second metering pump and wriggling parallel connection of pumps with culture chamber, pressure for pulse pressure and stablizes arteries and veins at intravascular stent
The superposition of pressure, the record changed by measuring apparatus of diameter to stent outside diameter, adjusts the second range of metering pump, wriggling pump discharge and the
Three throttle valve openings, adjust and stablize pulse pressure and pulse pressure in culture chamber, meet the test request to diameter change, complete stent footpath
Tested to fatigue mechanics;
Below by drawings and examples, technical scheme is described in further detail.
Brief description of the drawings
Fig. 1 is schematic structural view of the invention;
Fig. 2 is blood vessel clamper structure diagram of the present invention;
Fig. 3 is return circuit testing device structure diagram of the present invention;
Fig. 4 adjusts schematic diagram for multichannel of the present invention.
Wherein:1. the first multiple-pass joint;2. first throttle valve;3. intravascular stent;4. replacement vessels;5. culture chamber;6.
Blood vessel clamper;The first gaskets of 6-1.;6-2. spring;6-3. bolt;The second gaskets of 6-4.;6-5. nut;Outside 6-6. clampers
Shell;6-7. thrombus substitutes;7. the first return circuit testing device;7-1. flowmeter;7-2. pressure transmitter;7-3. shut-off valve;7-
4. recorder;8. second servo loop test device;9. second throttle;10. the second multiple-pass joint;11. the first four-way valve;12. the
One triple valve;13. pressure gauge;14. counterbalance valve;15. filter;16. Back flow bottle;17. the second triple valve;18. the first metering pump;
19. the second metering pump;20. the second four-way valve;21. peristaltic pump;22. measuring apparatus of diameter;23. the 3rd throttle valve;24. flow tube of pulsing
Road;25. biological fermentation tank.
Embodiment
In the description of the present invention, it is to be understood that term " interior ", " outer ", " side ", " one end ", " one side " etc. refer to
The orientation or position relationship shown is based on orientation shown in the drawings or position relationship, is for only for ease of the description present invention and simplifies
Description, rather than the device or element of instruction or hint meaning must have specific orientation, with specific azimuth configuration and behaviour
Make, therefore be not considered as limiting the invention.In addition, term " first ", " second " are only used for description purpose, and cannot manage
Solve to indicate or implying relative importance or the implicit quantity for indicating indicated technical characteristic.Thus, define " first ",
One or more this feature can be expressed or be implicitly included to the feature of " second ".In the description of the present invention, unless
It is otherwise noted, " multiple " are meant that two or more.
In the description of the present invention, it is necessary to illustrate, unless otherwise clearly defined and limited, term " installation ", " phase
Even ", " connection " should be interpreted broadly, for example, it may be being fixedly connected or being detachably connected, or be integrally connected;Can
To be mechanical connection or be electrically connected;It can be directly connected, can also be indirectly connected by intermediary, Ke Yishi
Connection inside two elements.For the ordinary skill in the art, with concrete condition above-mentioned term can be understood at this
Concrete meaning in invention.
The present invention provides a kind of degraded of intravascular stent and fatigue property test bioreactor, using metering pump and compacted
Dynamic pump provides Pulsating Flow for the external degradation experiment of intravascular stent and testing fatigue, is used cooperatively and can independently adjusted by throttle valve
Save the flow and pressure at different branch intravascular stent, by peristaltic pump and metering pump with the use of can realize under high frequency plus
Prompt drop solution performance test, is provided closer to internal fluid environment, so as to fulfill blood vessel using biological fermentation tank for intravascular stent
Stent external degradation and fatigue property test under different blood pressure pulsations characteristics and flow.
Please refer to Fig.1, Fig. 2 and Fig. 3, a kind of intravascular stent degraded of the present invention and fatigue property test bioreactor,
Including the first multiple-pass joint 1, first throttle valve 2, intravascular stent 3, replacement vessels 4, culture chamber 5, blood vessel clamper 6, first
Return circuit testing device 7, second servo loop test device 8, second throttle 9, the second multiple-pass joint 10, the first four-way valve 11, first
Triple valve 12, pressure gauge 13, counterbalance valve 14, filter 15, Back flow bottle 16, the second triple valve 17, the first metering pump 18, second meter
The 19, second four-way valve 20 of amount pump, peristaltic pump 21, measuring apparatus of diameter 22, the 3rd throttle valve 23,24 biological fermentation tank of Pulsating Flow pipeline
25, flowmeter 7-1, pressure transmitter 7-2, shut-off valve 7-3, recorder 7-4.
21 and second metering pump of peristaltic pump 19 is in parallel, its entrance passes through 25 port of export of the second four-way valve 20 and biological fermentation tank
It is connected, its outlet is connected by the second triple valve 17 with the first four-way valve 11, and 11 first exit end of the first four-way valve is sequentially connected with
Second multiple-pass joint 10, second throttle 9, the first return circuit testing device 7, replacement vessels 4, intravascular stent 3, first throttle valve
2nd, the first threeway is passed through at 25 first entrance of the first multiple-pass joint 1 and biological fermentation tank, 11 second outlet end of the first four-way valve successively
Valve 12, second servo loop test device 8, culture chamber 5, the 3rd throttle valve 23 are connected with the second entrance of biological fermentation tank 25.
Peristaltic pump 21, which produces, stablizes pulse pressure, and the second metering pump 19 produces pulse pressure, both are superimposed offer and stablize pulse pressure and arteries and veins
The pulsating flow surrounding that can adjust alone of pressure of fighting, coordinates first throttle valve 2 and second throttle 9, it can be achieved that multichannel is independently adjusted
Section.
First metering pump, 18 import is connected by the second four-way valve 20 with biological fermentation tank 25, and outlet passes through the first triple valve
12 are connected with culture chamber 5.By the cooperation of the first metering pump 18 and the second metering pump 19, it can meet that the accelerated corrosion under high frequency is tired
Labor requirement.
Referring to Fig. 3,3 entrance of intravascular stent by recorder 7-4 record in real time pressure transmitter 7-2 pressure change and
The changes in flow rate of flowmeter 7-1.
5 upper and lower surface of culture chamber uses poly (methyl methacrylate) plate, and measuring apparatus of diameter 22 is set parallel to 4 cross section of replacement vessels
Put, record the changing rule of its diameter.The replacement vessels 4 have elasticity and a biocompatibility, its compliance for 3%~
5%.
Referring to Fig. 2, above-mentioned blood vessel clamper 6 by the first gasket 6-1, spring 6-2, bolt 6-3, the second gasket 6-4,
Nut 6-5, clamper shell 6-6, thrombus substitute 6-7 compositions, the curvature by varying clamper shell 6-6 can be simulated not
With the degradation characteristic of intravascular stent under curvature 3, the first gasket 6-1, spring 6-2, bolt 6-3, the second gasket 6-4, nut are used
6-5 connection clamper shell 6-6, can meet the radial dilatation requirement of intravascular stent 3.
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, the technical solution in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is
Part of the embodiment of the present invention, instead of all the embodiments.The present invention being described and shown in usually here in attached drawing is real
Applying the component of example can be arranged and be designed by a variety of configurations.Therefore, the present invention to providing in the accompanying drawings below
The detailed description of embodiment be not intended to limit the scope of claimed invention, but only represent the selected reality of the present invention
Apply example.Based on the embodiments of the present invention, those of ordinary skill in the art are obtained without creative efforts
Every other embodiment, belong to the scope of protection of the invention.
The degradation property test that multichannel is separately adjustable under 1 high frequency of embodiment
1. equipment sterilizes.
First multiple-pass joint 1, first throttle valve 2, replacement vessels 4, culture chamber 5, second throttle more than 9, second connect
First 10, first four-way valve 11, the first triple valve 12, counterbalance valve 14, filter 15, Back flow bottle 16, the second triple valve the 17, the 2nd 4
Port valve 20, the 3rd throttle valve 23, Pulsating Flow pipeline 24, biological fermentation tank 25, shut-off valve 7-3 carry out 120 DEG C of high-temperature sterilizations 25 and divide
Clock;Pressure gauge 13, flowmeter 7-1, pressure transmitter 7-2 are sequentially connected using Pulsating Flow pipeline 24, by 18 He of the first metering pump
Circuit is connected serially to after second metering pump, 19 parallel connection, starts the first metering pump 18 and the second metering pump 19, using 75% alcohol to returning
Road immersion sterilizing, then, utilizes sterile PBS solution and 1% dual anti-mixed liquor flush loop 5 times (changing liquid every 20 minutes).Go out
Put after bacterium to superclean bench.
2. in superclean bench, replacement vessels 4 are installed into culture chamber 5, utilize sacculus dilating catheter and conveying
System expands intravascular stent 3 in replacement vessels 4, and blood vessel clamper 6 is installed to intravascular stent substitute 4.
3. sterile PBS solution and 1% dual anti-mixed liquor are added in biological fermentation tank 25, by temperature control at 37 DEG C ± 2 DEG C,
PH is controlled 7.40 ± 0.05.
4. it is sequentially connected the first multiple-pass joint 1 using Pulsating Flow pipeline 24;First throttle valve 2;Replacement vessels 4;First
Return circuit testing device 7;Second servo loop test device 8;Second throttle 9;Second multiple-pass joint 10;First four-way valve 11;First
Triple valve 12;Pressure gauge 13;Counterbalance valve 14;Filter 15;Back flow bottle 16;Second triple valve 17;First metering pump 18;Second meter
Amount pump 19;Second four-way valve 20;Peristaltic pump 21;Measuring apparatus of diameter 22;3rd throttle valve 23;Biological fermentation tank 25.
5. the flow of regulating loop, pressure and frequency.
Poiseuille equation is specially:
Wherein, piFor inlet pressure, p0For exit pressure, r is pipe radius, and η is fluid viscosity, and L grows for pipeline
Degree.
The ratio of pressure difference and flow is known as resistance and represents as follows:
As shown in figure 4, main line inlet pressure and total flow are respectively PiAnd Qt, the pressure at the n-th branch vessel stent 3
It is respectively P with flownAnd Qn, 3 inlet second throttle of intravascular stent, 9 resistance is R2n-1, 2 resistance of exit first throttle valve
For R2n, main line exit pressure is p0, coordinate adjusting first throttle valve 2, second throttle 9, the second metering pump 19 to meet to prop up
Road is to pressure PnWith flow QnDemand for independence.
Flow curve is approximately that SIN function is as follows at intravascular stent 3:
Qt=(A sin (ω t)+A)+Qm
Wherein, QtFor certain moment flow;Δ Q=2A is difference in flow;QmFor regime flow.
Average discharge:
Pressure curve is approximately that SIN function is as follows at intravascular stent 3:
Pt=(B sin (ω t)+B)+Pm
Average pulse pressure:
Wherein, PtFor certain moment pressure;Δ P=2B is pulse pressure;PmTo stablize pulse pressure.
Test request:
Pressure pulse pressure (the difference Δ P of systolic pressure and diastolic pressure) 0~120mmHg in one cycle;
Stablize pulse pressure PmIn 75mmHg~120mmHg;Average discharge at intravascular stentFor 200ml/min~250ml/
min。
Adjusting method is as described below:
(a) at for the n-th branch vessel stent 3, pulse pressure Δ Pn=Δ QnR2n=2AnR2n, stablize pulse pressure Pmn=
QmnR2n, average pulse pressure(exit pressure is approximately atmospheric pressure, p0=0) it is, flat at intravascular stent 3
Equal flowDifference in flow difference in flow Δ Q in each stroke of branchn=2An.Try to achieve Adjusting 2 resistance of first throttle valve isMeet test to pulse pressure Δ PnWith stablize pulse pressure PmnRequirement.
(b) it is 1.2-36Hz to adjust the first metering pump 18 and 19 motor of the second metering pump frequency, and phase difference isAdjust first
18 stroke of metering pump and 23 aperture of the 3rd throttle valve, meet that branch is to pulse pressure Δ P requirements under high frequency.Adjust the second metering pump 19
Each stroke difference in flow be Δ Q=Δs Q1+ΔQ2+…+ΔQn(ΔQnFor nth bar bypass flow stroke difference in flow), adjust compacted
Dynamic pump 21, flow Qm=Qm1+Qm2+…+Qmn(QmnFor nth bar branch regime flow).
(c) for the n-th branch,(For main line entrance average pressure,It is flat for main line outlet
Equal pressure).Adjust 9 resistance R of second throttle2n-1(the n-th branch) and R1(first branch), makes R2n-1And R1Meet relational expressionSo as to meet intravascular stent test to average discharge(the n-th branch vessel stent
The average discharge at place) requirement.Counterbalance valve 14 is adjusted at the same time, ensures circuit safety.
6. observing the extent of corrosion of intravascular stent 3, the diameter change feelings of intravascular stent 3 are recorded using measuring apparatus of diameter 22
Condition.
7. shut-off valve 7-3, the first metering pump 18, the second metering pump 19 and peristaltic pump 21 are closed, will be after different corrosion weeks
The intravascular stent 3 of phase takes out from replacement vessels 4, records macroscopic features and carries out mechanical test.
Embodiment 2
The separately adjustable Steady flow tests of multichannel
1. equipment sterilizes
First multiple-pass joint 1, first throttle valve 2, replacement vessels 4, culture chamber 5, second throttle more than 9, second connect
First 10, first four-way valve 11, counterbalance valve 14, filter 15, Back flow bottle 16, Pulsating Flow pipeline 24, biological fermentation tank 25, shut-off valve
7-3 120 DEG C of progress high-temperature sterilizations 25 minutes;Pressure gauge 13, flowmeter 7-1, pressure are sequentially connected using Pulsating Flow pipeline 24 to become
Device 7-2 is sent, starts peristaltic pump 21, circuit is soaked using 75% alcohol and is sterilized, it is then, dual anti-using sterile PBS solution and 1%
Mixed liquor flush loop 5 times (changing liquid every 20 minutes).Put after sterilizing to superclean bench.
2. in superclean bench, replacement vessels 4 are installed into culture chamber 5, utilize sacculus dilating catheter and conveying
System expands intravascular stent 3 in replacement vessels 4, and blood vessel clamper 6 is installed to intravascular stent substitute 4.
3. sterile PBS solution and 1% dual anti-mixed liquor are added in biological fermentation tank 25, by temperature control at 37 DEG C ± 2 DEG C,
PH is controlled 7.40 ± 0.05.
4. it is sequentially connected the first multiple-pass joint 1 using Pulsating Flow pipeline 24;First throttle valve 2;Replacement vessels 4;First
Return circuit testing device 7;Second throttle 9;Second multiple-pass joint 10;First four-way valve 11;Pressure gauge 13;Counterbalance valve 14;Filtering
Device 15;Back flow bottle 16;Peristaltic pump 21;Measuring apparatus of diameter 22;Biological fermentation tank 25
5. the flow of regulating loop, pressure and frequency.
Poiseuille equation is specially:
Wherein, piFor inlet pressure, p0For exit pressure, r is pipe radius, and η is fluid viscosity, and L grows for pipeline
Degree.
The ratio of pressure difference and flow is known as resistance and represents as follows:
Changes in flow rate is as follows at intravascular stent 3:
Wherein, QtFor certain moment flow;QmFor regime flow,For average discharge
Pressure curve is approximately that SIN function is as follows at intravascular stent 3:
Wherein, PtFor certain moment pressure;PmTo stablize pulse pressure,For average pulse pressure.
Test request:
Stablize pulse pressure PmIn 80mmHg~160mmHg;Regime flow Q at intravascular stentmFor 200ml/min~250ml/
min。
For the n-th branch, exit pressure is approximately atmospheric pressure (p0=0),(QmnN-th branch stationary flow
Amount, pmnN-th branch stablizes pressure),Adjust first throttle valve resistanceIt can meet blood vessel
Stent is tested to pressure pnRequirement.Adjust second throttle resistance R2n-1, make R2n-1(nth bar branch) and R1(first branch
Road) meet relational expressionSo as to meet intravascular stent test to flow QmnWill
Ask.
The flow for setting peristaltic pump is Q=Qm=Qm1+Qm2+…+Qmn(QmnFor nth bar branch regime flow).Adjust at the same time
Counterbalance valve 14, ensures circuit safety.
6. observing the extent of corrosion of intravascular stent 3, the diameter change feelings of intravascular stent 3 are recorded using measuring apparatus of diameter 22
Condition.
7. close shut-off valve 7-3 and peristaltic pump 21, by after the intravascular stent 3 of different etching times from replacement vessels 4
Middle taking-up, records macroscopic features and carries out mechanical test.
Embodiment 3
Intravascular stent radial direction testing fatigue
1. equipment sterilizes.First throttle valve 2, second throttle 9, replacement vessels 4, culture chamber 5, the first four-way valve 11,
Counterbalance valve 14, filter 15, Back flow bottle 16, the second triple valve 17, the second four-way valve 20, the 3rd throttle valve 23, Pulsating Flow pipeline
24th, 120 DEG C of the progress of biological fermentation tank 25 high-temperature sterilization 25 minutes;Pressure gauge 13, flow are sequentially connected using Pulsating Flow pipeline 24
7-1, pressure transmitter 7-2 are counted, the second metering pump 19 is connected serially to circuit, starts the second metering pump 19, utilizes 75% alcohol pair
Circuit immersion sterilizing, then, utilizes sterile PBS solution and 1% dual anti-mixed liquor flush loop 5 times (changing liquid every 20 minutes).
Put after sterilizing to superclean bench.
2. in superclean bench, replacement vessels 4 are installed into culture chamber 5, utilize sacculus dilating catheter and conveying
System expands intravascular stent 3 in replacement vessels 4.
3. sterile PBS solution and 1% dual anti-mixed liquor are added in biological fermentation tank 25, by temperature control at 37 DEG C ± 2 DEG C,
PH is controlled 7.40 ± 0.05.
4. it is sequentially connected first throttle valve 2 using Pulsating Flow pipeline 24;Replacement vessels 4;Second throttle 9;Second time
Road test device 8;First four-way valve 11;Pressure gauge 13;Counterbalance valve 14;Filter 15;Back flow bottle 16;Second triple valve 17;The
Two metering pumps 19;Peristaltic pump 21;Second four-way valve 20;Measuring apparatus of diameter 22;3rd throttle valve 23;Biological fermentation tank 25, is closed
First throttle valve 2 and second throttle 9.
5. adjusting the 3rd throttle valve 23 and the second metering pump 19, pulse pressure (systolic pressure and diastolic pressure in culture chamber 5 are adjusted
Difference Δ P), adjust 21 flow-rate adjustment of peristaltic pump its stable pulse pressure, it is met that 3 radial direction testing fatigue of intravascular stent becomes diameter
The requirement of change.
6. observing the fatigue conditions of intravascular stent 3, the diameter change feelings of intravascular stent 3 are recorded using measuring apparatus of diameter 22
Condition.
7. closing 21 and second metering pump 19 of peristaltic pump, will be substituted after the intravascular stent 3 in different fatigue cycle from blood vessel
Taken out in thing 4, record macroscopic features and carry out mechanical test.
The present invention can meet blood vessel by providing intravascular stent degraded and fatigue property test fluid and mechanical environment in vitro
Stent is in high frequency, multichannel is separately adjustable and to average discharge, stablize the cooperation requirement of pulse pressure and pulse pressure, and can see in real time
Degraded and the degree of fatigue of intravascular stent are examined, records intravascular stent diameter change
Above content is merely illustrative of the invention's technical idea, it is impossible to protection scope of the present invention is limited with this, it is every to press
According to technological thought proposed by the present invention, any change done on the basis of technical solution, each falls within claims of the present invention
Protection domain within.