CN109044576B - Aortic blood pressure controlled drug delivery stent and blood pressure controlled drug delivery system - Google Patents

Abstract

The invention provides an aortic blood pressure control drug-loaded stent and a blood pressure control drug release system, belonging to the technical field of intracavity angiography. The aortic blood pressure controlled drug-delivery stent comprises a stent main body, a lining tectorial membrane, a conductive drug-delivery tectorial membrane, a piezoresistor and a power supply; the inner lining coating film is coated on the inner surface of the bracket main body, and the conductive medicine carrying coating film is coated on the outer surface of the bracket main body; when the pressure borne by the piezoresistor is larger than a threshold value, the resistance value is reduced, micro-current exists in the circuit, and the conductive medicine carrying film can promote medicine release and micro-current conduction to the body surface. The aortic blood pressure control drug-delivery stent system can perform noninvasive monitoring on the aortic blood pressure of a patient, evaluate the treatment effect of aortic dissection and perform risk early warning, and can perform preventive accurate drug treatment of local focus.

Description

Aortic blood pressure controlled release drug-loaded stent and blood pressure control drug release system

Technical field

The present invention relates to the technical field of aortic blood pressure monitoring, and specifically to an aortic blood pressure controlled release drug-loaded stent and a blood pressure control drug release system.

Background technique

Aortic dissection refers to aortic disease in which arterial blood enters the aortic wall through a breach in the aortic intima, causing the aortic media to separate from the aortic adventitia, resulting in a false lumen. Currently, the treatment of aortic dissection can reshape the aorta through an aortic stent and block or partially block the false lumen blood flow, thereby treating aortic dissection.

However, the occurrence of adverse events may seriously affect the therapeutic effect and prognosis of aortic dissection. For example, there is a mismatch between the graft and the tube wall, resulting in incomplete sealing of the tear, abnormalities in the systemic or local blood system, or special dynamic characteristics ( Under the impact of blood flow (such as blood pressure fluctuations), the false lumen will not be completely thrombosed (or even have no thrombus), which may lead to: 1) the blood flow in the true lumen cannot be restored, and the false lumen will progressively expand like a tumor; 2) the false lumen will Blood is supplied from the distal rupture, resulting in new retrograde tearing dissection; 3) The special form of false lumen thrombosis can lead to differences in the mechanical strength of the wall and the emergence of local vulnerable areas.

Since the patient's aortic blood pressure cannot be non-invasively monitored, it is difficult to evaluate the prognosis and complication risk of endovascular isolation of aortic dissection; at the same time, there is a lack of preventive and precise treatment of locally fragile vascular walls in patients with hypertension. means.

Contents of the invention

In view of the problems existing in the above-mentioned prior art, the present invention provides an aortic blood pressure controlled release drug-loaded stent and a blood pressure controlled drug release system, which can non-invasively monitor the patient's aortic blood pressure and improve the therapeutic effect of aortic dissection. Assess and carry out risk warning, and at the same time provide a preventive and precise treatment method when local lesions are at high risk.

In a first aspect, an embodiment of the present invention provides an aortic blood pressure controlled-release drug-loaded stent, which includes a stent body, a conductive drug-loaded coating, a varistor and a power supply; the lining coating is coated on the stent body On the inner surface of the stent body, a conductive drug-loaded coating is coated on the outer surface of the stent body;

The power supply, the varistor and the main body of the stent form a loop. When the pressure on the varistor is greater than a threshold, the resistance decreases, a microcurrent exists in the loop, and the conductive drug-loaded coating The membrane will facilitate drug release and conduction of the microcurrent to the body surface.

In conjunction with the first aspect, the embodiment of the present invention provides a first possible implementation of the first aspect, wherein a supporting bracket wire is provided on the bracket body, and the varistor and the power supply are embedded in the bracket. On the main body, a circuit is formed by connecting the main body of the bracket.

In conjunction with the first possible implementation of the first aspect, an embodiment of the present invention provides a second possible implementation of the first aspect, wherein the support stent wire is along the length direction of the stent body and surrounds the stent body. The circumferential direction of the bracket body is set.

In conjunction with the first possible implementation of the first aspect, embodiments of the present invention provide a third possible implementation of the first aspect, wherein the support bracket wire, the varistor and the power supply are connected to form multiple loops, with at least one varistor connected to each loop.

In conjunction with the first aspect, embodiments of the present invention provide a fourth possible implementation of the first aspect, wherein the conductive drug-loaded coating includes a drug release layer, a nanosphere storage layer and a conductive coating layer arranged in sequence; Drug release micropores are formed on the drug release layer; drug-loaded nanospheres are included in the nanosphere storage layer.

In combination with the fourth possible implementation manner of the first aspect, embodiments of the present invention provide a fifth possible implementation manner of the first aspect, wherein the conductive coating layer includes a thin film layer and is embedded on the thin film layer. A metal piece connected to the varistor.

Combined with the fourth possible implementation of the first aspect, the embodiment of the present invention provides a sixth possible implementation of the first aspect, the diameter of the drug-loaded nanospheres is between 101 nm and 999 nm, and the diameter of the drug release micropores is less than 100 nm. .

In combination with the sixth possible implementation of the first aspect, embodiments of the present invention provide a seventh possible implementation of the first aspect, wherein the drug-loaded nanospheres are loaded with one of the following drugs: antihypertensive drugs, antihypertensive drugs, Coagulants, glucocorticoids, nonsteroidal anti-inflammatory drugs, vasoactive drugs, and endothelial repair drugs.

Combined with the first aspect, embodiments of the present invention provide an eighth possible implementation of the first aspect, wherein the lining film and the conductive drug-carrying film are made of expanded polytetrafluoroethylene material.

In a second aspect, embodiments of the present invention also provide a blood pressure control drug release system, including a monitoring device and the aortic blood pressure controlled release drug-loaded stent described in any one of the above first aspects; the aortic blood pressure controlled release drug The drug-loaded stent is used to be placed in the blood vessel, and the monitoring device is used to be connected to the body surface.

The embodiments of the present invention bring the following beneficial effects:

The aortic blood pressure controlled-release drug-loaded stent and the aortic blood pressure monitoring system provided by the embodiments of the present invention, wherein the aortic blood pressure controlled-release drug-loaded stent includes a stent body, a lining coating, a conductive drug-loading coating, a varistor and a Power supply; the lining coating is coated on the inner surface of the stent body, and the conductive drug-loaded coating is coated on the outer surface of the stent body; the power supply, the varistor, and the stent body are connected to form a loop. When the varistor is When the pressure is greater than the threshold, the resistance decreases, and a microcurrent exists in the circuit. The conductive drug-laden coating conducts the microcurrent to the body surface, so that the monitoring equipment connected to the body surface can detect changes in aortic blood pressure; the microcurrent simultaneously It will break down the drug-loaded nanospheres in the conductive drug-loaded coating to achieve the release of the loaded drugs for aortic blood pressure control. The aortic blood pressure controlled release drug-loaded stent can non-invasively monitor the patient's aortic blood pressure, evaluate the therapeutic effect of aortic dissection and provide risk warning, and at the same time provides a preventive and precise treatment method when local lesions are at high risk. .

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description, claims and appended drawings.

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are given below and described in detail with reference to the accompanying drawings.

Description of drawings

In order to more clearly explain the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description The drawings illustrate some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting any creative effort.

Figure 1 is a schematic structural diagram of an aortic blood pressure controlled release drug-loaded stent provided by an embodiment of the present invention;

Figure 2 is a circuit schematic diagram of an aortic blood pressure controlled release drug-loaded stent provided by an embodiment of the present invention;

Figure 3 is a schematic diagram of the inner surface structure of the conductive drug-loaded coating provided by one embodiment of the present invention;

Figure 4 is a schematic diagram of the outer surface structure of a conductive drug-loaded coating provided by an embodiment of the present invention;

Figure 5 is a schematic structural diagram of a stent body provided by an embodiment of the present invention;

Figure 6 is a schematic longitudinal cross-sectional structural diagram of a conductive drug-loaded coating provided by an embodiment of the present invention.

Icon: 10-stent body; 11-power supply; 12-varistor; 13-support stent wire; 20-conductive drug-laden coating; 21-metal sheet; 30-lining coating; 210-drug release layer; 220 -Drug release micropores; 230-drug-loaded nanospheres; 240-nanosphere storage layer; 250-conductive coating layer.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Embodiments. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the invention provided in the appended drawings is not intended to limit the scope of the claimed invention, but rather to represent selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

In view of the current inability to non-invasively monitor a patient's aortic blood pressure and the lack of preventive and precise treatment methods for locally fragile blood vessel walls when patients have high blood pressure, embodiments of the present invention provide an aortic blood pressure controlled release drug-loaded stent and a The blood pressure control drug release system can non-invasively monitor the patient's aortic blood pressure, evaluate the treatment effect of aortic dissection and provide risk warning. It also provides a preventive and precise treatment method when local lesions are at high risk. The aortic blood pressure controlled release drug-loaded stent of the present invention is first introduced in detail below.

Embodiment 1

This embodiment provides an aortic blood pressure controlled release drug-loaded stent, as shown in Figures 1 to 6. The aortic blood pressure controlled release drug-loaded stent includes a stent body 10, a conductive drug-loaded coating 20, and a varistor 12 and power supply 11. The conductive drug-loaded coating 20 covers the outer surface of the stent body 10 . The varistor 12 is connected to the power supply 11 to form a loop. When the pressure on the varistor 12 is greater than the threshold value, the resistance decreases and a microcurrent exists in the loop. The conductive drug-loaded coating 20 conducts the microcurrent in the loop to the body. surface. The maximum microcurrent in the loop is less than 10mA.

Among them, as shown in Figure 5, the stent body 10 can be made of nickel-titanium alloy wire. Ni-titanium alloy has shape memory properties and can automatically restore its own plastic deformation to its original shape at a certain temperature. Its expansion rate is more than 20%, its fatigue life reaches 107 times, its damping characteristics are 10 times higher than ordinary springs, and its wear resistance and corrosion resistance are better than the best medical stainless steel at present. It is a high-quality functional material. The stent body 10 is in a continuous spiral sine wave configuration, and can also be in a grid shape, a braided mesh, a "Z" shaped wave or other mesh shapes. Regarding the processing technology of nickel-titanium alloy, it can be formed by braiding metal wires and heat-setting them, then welding, bundling, and socketing them, or laser cutting metal tubes to shape them.

The support body 10 is provided with a support wire 13. The varistor 12 and the power supply 11 are embedded in the support body and connected through the support wire 13 to form a circuit. A part of the supporting bracket wires 13 is arranged along the length direction of the stent body, and the other part of the supporting bracket wires 13 is arranged around the circumferential direction of the stent body 10 in an annular shape, which can be called a stent ring.

As shown in Figure 2, the support wire 13 is connected to the power supply 11 to form multiple loops, and at least one varistor 12 is connected to each loop and cannot be short-circuited. It can also be said that at least one varistor 12 is arranged between every two support rings. The varistor 12 is a varistor material resistor embedded in the main body of the stent. When the blood pressure is higher than a threshold, the resistance is small. The threshold can be set to any value in the range of 50-200 mmHg.

As shown in Figures 3, 4 and 6, the conductive drug-loaded coating 20 includes a drug release layer 210, a nanosphere storage layer 240 and a conductive coating layer 250 arranged in sequence. Drug release micropores 220 are formed on the drug release layer 210, and the diameter of the drug release micropores 220 is less than 100 nm. The nanosphere storage layer 240 contains drug-loaded nanospheres 230 . The diameter of the drug-loaded nanosphere 230 is between 101 nm and 999 nm. The drug-loaded nanosphere 230 is loaded with one of the following drugs: antihypertensive drugs, procoagulant drugs, glucocorticoids, nonsteroidal anti-inflammatory drugs, vasoactive drugs, and endothelial repair-promoting drugs. The principle of drug release from drug-loaded nanospheres 230 is that a human body-safe microcurrent is formed in the circuit to breakdown the drug-loaded nanospheres, allowing the drug to pass through the drug release micropores 220 smoothly. The conductive coating layer 250 includes a thin film layer and a metal sheet 21 embedded on the thin film layer. The metal sheet 21 is connected to the varistor 12 to conduct the microcurrent in the circuit to the body surface. Specifically, the varistor 12 has a certain thickness, the metal sheet 21 is closely attached to the varistor 12, and the film layer is made of expanded polytetrafluoroethylene (ePTFE). Vinyl fluoride is an ideal insulating material and has good biocompatibility. There is no conduction between the metal pieces, which can prevent the aortic blood pressure controlled-release drug-loaded stent from forming a short circuit in the body.

The power supply 11 can use a miniature lithium iodine battery, which can generate and output electrical pulses with a maximum voltage of less than 36V.

The aortic blood pressure controlled release drug-loaded stent also includes a lining coating 30 . The lining film 30 is attached to the inner surface of the stent body 10 to prevent contact between the circuit and blood. The lining coating 30 is also made of expanded polytetrafluoroethylene material.

The varistor 12 and the power supply 11 are both arranged between the lining film 30 and the conductive drug-carrying film 20 . The circuit formed by the power supply, varistor, and bracket body cannot be short-circuited.

In the aortic blood pressure controlled release drug-loaded stent provided by the embodiment of the present invention, the main body of the stent is placed in the blood vessel and acts on the dissection breach, which can seal the dissection breach and support the vascular intima, restore the true lumen blood flow, and thereby realize the operation. Purpose. There is a power supply and a varistor inside the main body of the stent. Without affecting the mechanical properties of the main body of the stent, when the pressure on the varistor is less than the threshold, the loop current is basically 0. When the pressure on the varistor is greater than the threshold (for example, 140mmHg, the threshold of high blood pressure, with the risk of recurrence of aortic dissection), the resistance of the varistor is greatly reduced, causing microcurrent to exist in the circuit. Through the metal sheet on the conductive drug-loaded coating, the microcurrent can penetrate the drug-loaded nanospheres, allowing a variety of optional drugs to reach the lesions through the drug release micropores, playing a preventive and precise treatment role when local lesions are at high risk; at the same time It can reflect different potentials detected at different body surface positions. By connecting the monitoring equipment to the body surface, the changes in potential signals on the body surface can be detected. Based on the changes in the potential signals, the intra-aortic blood pressure can be obtained, making it simple and accurate. Monitoring the aortic blood pressure of patients during or after surgery provides a valuable risk assessment indicator in the field of endovascular angiology.

Furthermore, before the power fails and the drug is exhausted, the aortic blood pressure controlled release drug-loaded stent can release drugs to local lesions according to the aortic blood pressure and accurately reflect the specific value of the aortic blood pressure, thereby achieving preventive and accurate Treatment and assessment of the risk of aortic dissection recurrence or rupture, especially in the high-risk period during the perioperative period and within 3 months after surgery, preventive and precise treatment and monitoring of aortic blood pressure at the lesion site will have great clinical significance value. After the power supply fails and the drug is exhausted, the aortic blood pressure controlled release drug-loaded stent can still play the role of the aortic stent graft.

The aortic blood pressure measured through the aortic blood pressure controlled release drug-loaded stent provided by the embodiment of the present invention can preventively and accurately guide patients to control blood pressure medication, instead of relying solely on the medication experience of doctors and pharmacists; not only can blood pressure be controlled Peak value can also be used to control blood pressure fluctuations. At the same time, it can provide preventive and precise drug treatment for local lesions when the aortic blood pressure is higher than the high-risk threshold.

To sum up, the aortic blood pressure controlled release drug-loaded stent provided by the embodiment of the present invention includes a stent body, a lining coating, a conductive drug-loading coating, a varistor and a power supply; the lining coating is coated on the On the inner surface of the stent body, a conductive drug-laden coating covers the outer surface of the stent body; the power supply, the varistor, and the stent body are connected to form a loop. When the pressure on the varistor is greater than the threshold, the resistance decreases. , there is a microcurrent in the circuit, and the conductive drug-loaded coating conducts the microcurrent to the body surface, so that the monitoring equipment connected to the body surface can monitor changes in aortic blood pressure; at the same time, the microcurrent breaks down the drug-loaded nanospheres, allowing the drug to Smoothly acts on the lesions through the drug release micropores. The aortic blood pressure controlled release drug-loaded stent and blood pressure controlled drug release system can non-invasively monitor the patient's aortic blood pressure, evaluate the therapeutic effect of aortic dissection and provide risk warning, and at the same time provide a method for high-risk local lesions. Preventive and precise treatment methods.

Embodiment 2

Embodiments of the present invention also provide an aortic blood pressure monitoring system, including a monitoring device and an aortic blood pressure controlled-release drug-loaded stent. The aortic blood pressure controlled release drug-loaded stent can be placed in the blood vessel using the aortic blood pressure controlled release drug-loaded stent provided in the first embodiment. Monitoring equipment is used to connect to the body surface and detect potential signals on the body surface.

Specifically, similar to an electrocardiograph, the monitoring device may include a plurality of contact electrodes connected to the body surface, and a host connected to the contact electrodes through lead wires or wirelessly, for detecting body surface potential.

When the pressure on the varistor in the aortic blood pressure controlled-release drug-loaded stent is greater than the threshold, the resistance of the varistor is greatly reduced, causing microcurrent to exist in the circuit. Through the metal sheet on the conductive drug-laden coating, microcurrent can reflect different potentials detected at different body surface locations. The contact electrode of the monitoring device is connected to the body surface, and the monitoring device can detect changes in the potential signal on the body surface. Based on the changes in the potential signal, the intra-aortic blood pressure can be obtained.

The aortic blood pressure controlled release drug-loaded stent and the blood pressure controlled drug release system provided by the embodiments of the present invention have the same technical features, so they can also solve the same technical problems and achieve the same technical effects.

It should be noted that in the description of the embodiments of the present invention, unless otherwise clearly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection or a fixed connection. Detachable connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limitations of the invention. Furthermore, the terms “first”, “second” and “third” are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Finally, it should be noted that the above-mentioned embodiments are only specific implementations of the present invention and are used to illustrate the technical solutions of the present invention rather than to limit them. The protection scope of the present invention is not limited thereto. Although refer to the foregoing The embodiments illustrate the present invention in detail. Those of ordinary skill in the art should understand that any person familiar with the technical field can still modify the technical solutions recorded in the foregoing embodiments within the technical scope disclosed by the present invention. It may be easy to think of changes, or equivalent substitutions of some of the technical features; and these modifications, changes or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and they should all be included in the present invention. within the scope of protection. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (8)

1. An aortic blood pressure controlled release drug-loaded stent, characterized in that it includes a stent body, a lining coating, a conductive drug-loading coating, a varistor and a power supply; the lining coating is coated on the stent body On the inner surface, a conductive drug-loaded coating covers the outer surface of the stent body; The power supply, the varistor and the main body of the stent form a loop. When the pressure on the varistor is greater than a threshold, the resistance decreases, a microcurrent exists in the loop, and the conductive drug-loaded coating The membrane will promote drug release and conduction of the microcurrent to the body surface; The support body is provided with a support wire, and the varistor and the power supply are embedded in the support body and connected through the support wire to form a circuit; The conductive drug-loaded coating includes a drug release layer, a nanosphere storage layer and a conductive coating layer arranged in sequence; drug release micropores are formed on the drug release layer; the nanosphere storage layer contains drug-loaded nanoparticles. ball. 2. The aortic blood pressure controlled release drug-loaded stent according to claim 1, wherein the support stent wire is arranged along the length direction of the stent body and the circumferential direction surrounding the stent body. 3. The aortic blood pressure controlled-release drug-loaded stent according to claim 1, characterized in that the support stent wire, the varistor and the power supply are connected to form multiple loops, and at least one pressure-sensitive resistor is connected in each loop. Sensitive resistor. 4. The aortic blood pressure controlled release drug-loaded stent according to claim 1, wherein the conductive coating layer includes a thin film layer and a metal sheet embedded on the thin film layer, and the metal sheet and the Varistor connections. 5. The aortic blood pressure controlled release drug-loaded stent according to claim 1, wherein the diameter of the drug-loaded nanospheres is between 101 nm and 999 nm, and the diameter of the drug release micropores is less than 100 nm. 6. The aortic blood pressure controlled release drug-loaded stent according to claim 5, characterized in that the drug-loaded nanospheres are loaded with one of the following drugs: antihypertensive drugs, procoagulant drugs, glucocorticoids, non-steroidal anti-inflammatory drugs. Inflammatory drugs, vasoactive drugs, and endothelial repair drugs. 7. The aortic blood pressure controlled release drug-loaded stent according to claim 1, wherein the lining film and the conductive drug-loaded film are made of expanded polytetrafluoroethylene. 8. A blood pressure control drug release system, characterized by comprising monitoring equipment and the aortic blood pressure controlled release drug-loaded stent according to any one of claims 1 to 7; the aortic blood pressure controlled release drug-loaded stent The monitoring device is intended to be placed inside the body, and the monitoring device is intended to be connected to the surface of the body.