LU500428B1 - Device for Treating Severe Pulmonary Arterial Hypertension Caused by Patent Ductus Arteriosus and Using Method Thereof - Google Patents

Abstract

The invention relates to a device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus and a using method thereof. The device comprises a valve stent and a delivery system. The catheter stent comprises a vascular stent, fixators at both ends and a unidirectional membrane. The vascular stent is tubular, the side wall is a memory metal woven mesh, and the inner wall is attached with plastic film. The fixators at both ends are welded at two ends of the vascular stent. Developing coatings are attached to the tip parts of the fixators at both ends. The unidirectional membrane is a funnel-shaped biological valve, which is fixed in the vascular stent. The delivery system comprises a sheath tube, a catheter and a push rod. The sheath tube is a plastic tube with developing rings at both ends. The tail end is connected with the catheter.

Description

DESCRIPTION Device for Treating Severe Pulmonary Arterial Hypertension Caused by Patent Ductus Arteriosus and Using Method Thereof

TECHNICAL FIELD The invention relates to the field of medical instruments, in particular to a device for treat severe pulmonary arterial hypertension caused by patent ductus arteriosus and a using method thereof.

BACKGROUND Pulmonary arterial hypertension refers to a hemodynamic and pathophysiological state in which the pulmonary artery pressure rises above a certain threshold. Pulmonary arterial hypertension can lead to right heart failure. It can be an independent disease, a complication or a syndrome. Its diagnostic criteria of hemodynamics were: the mean pulmonary artery pressure measured by right cardiac catheter was >25mmHg at sea level rest. Pulmonary arterial hypertension is a common and frequently-occurring disease with high morbidity and mortality, which should be paid great attention to. Patent ductus arteriosus is also the cause of pulmonary arterial hypertension. The ductus arteriosus was originally a normal blood flow channel between pulmonary artery and aorta in fetal period. Because of the pulmonary respiratory dysfunction at this time, pulmonary artery blood from the right ventricle enters the descending aorta through the duct, while blood from the left ventricle enters the ascending aorta. Therefore, the ductus arteriosus is necessary for the special circulation mode in embryonic period. After birth, the lung swelled and assumed the function of gas exchange, and the pulmonary circulation and systemic circulation performed their respective functions. Soon, the catheter was automatically closed due to disuse.

If patent ductus arteriosus is formed due to continuous patent, surgery should be performed to interrupt its blood flow.

Patent ductus arteriosus is a common congenital cardiovascular malformation, accounting for 12% ~ 15% of the total number of congenital heart diseases, and the number of females is about twice that of males.

About 10% of cases had other cardiovascular malformations.

The clinical manifestation of patent ductus arteriosus mainly depends on the amount of blood from aorta to pulmonary artery shunt, whether secondary pulmonary arterial hypertension occurs and its degree.

Mild patients may have no obvious symptoms, and severe patients may have heart failure.

Common symptoms include palpitation, shortness of breath, fatigue, respiratory infection and growth retardation.

Late pulmonary arterial hypertension is serious, and cyanosis may occur in the lower body when reverse shunt occurs.

During physical examination of patent ductus arteriosus, the typical sign is that a loud continuous machine-like murmur is heard between the second rib of the left edge of sternum, accompanied by tremor.

The second tone of pulmonary valve is hyperactive, but it is often concealed by loud noise.

Diastolic murmurs caused by relative mitral stenosis can still be heard in the apical area of patients with large shunt volume.

Blood pressure measurement showed that systolic blood pressure was mostly in normal range, while diastolic blood pressure decreased, so pulse pressure widened, and blood vessels in limbs had water pulse and shooting sound.

Infants can only hear systolic murmurs.

When pulmonary hypertension occurs in the late stage, the murmurs vary greatly, and only systolic murmurs may disappear, or they may be replaced by diastolic murmurs with pulmonary insufficiency.

At present, the method to deal with pulmonary arterial hypertension caused by patent ductus arteriosus is to take thoracotomy and close the ductus arteriosus. This method requires anesthesia to open the chest. It has long operation time, high risk, large wound area and long postoperative recovery time. At the same time, if patients with congenital heart disease completely block the arterial catheter, pulmonary hypertension still exists, and the problem of hypertension cannot be solved.

SUMMARY To solve the above problems, the scheme of the present invention is to provide a device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus and a using method thereof. A device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus comprises a catheter stent and a delivery system. The catheter stent comprises a vascular stent, fixators at both ends and a unidirectional membrane. The vascular stent is tubular, the side wall is a memory metal woven mesh, and the inner wall is attached with a plastic film. The fixators at both ends are rings formed by connecting inverted V-shaped memory metals and are welded at two ends of the vascular stent. The tip parts of the fixators at both ends are rounded corners, and developing coatings are attached to the rounded corners. The unidirectional membrane is a funnel-shaped soft silica gel membrane with front and rear openings and is fixed in the vascular stent. The delivery system comprises a sheath tube, a catheter and a push rod. The sheath tube is a plastic tube. Two ends of the sheath tube are provided with developing rings, and the tail end 1s connected with a catheter. The catheter is a vascular interventional catheter,

and the head end is connected with a sheath tube.

A push block is arranged at the head end of the push rod for vascular intervention guide wire.

The push block is a cylindrical plastic block, and the inner diameter is smaller than the sheath tube by 0.5mm.

Furthermore, the memory metal is a nickel-titanium memory alloy.

Furthermore, the hole projection shape of the mesh is rhombic.

The deformation direction of the mesh holes is that the rhombic holes extend transversely and shorten vertically.

Furthermore, the deformation direction of the fixators at both ends is to tilt around with the bottom surface of the vascular stent as a circle.

Furthermore, the plastic film is a silicone rubber membrane, and the developing coatings are gold coatings.

Furthermore, the developing rings are stainless steel rings.

The using method of the device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus comprises the following steps. (1) Establish femoral vein-inferior vena cava-right ventricle-pulmonary artery pathway. (2) Compress the diameter of the vascular stent, straighten the fixators at both ends, and place the catheter stent into the sheath tube. (3) Under X-ray, the sheath tube is guided into the femoral vein by using interventional guide wire until it reaches the pulmonary artery along the path.

Observe the developing rings at both ends of the sheath tube to judge whether the sheath tube enters the right ventricular arterial catheter. (4) Withdraw the guide wire, send the push rod into the catheter at the end of the sheath tube, pinch the push rod, pull back the sheath tube, thereby the push block leaves the catheter stent in the right ventricular arterial catheter.

(5) The memory metal of the catheter stent is restored to its original state. The diameter of the vascular stent is expanded outward, and the fixators at both ends are tilted around and clamped at both ends of the right ventricular arterial catheter. (6) Exit the delivery system from the pathway. Furthermore, the funnel-shaped narrow end of the unidirectional membrane points from the pulmonary artery to the right ventricular artery. Advantageous effects of the invention (1) After establishing the femoral vein-inferior vena cava-right ventricle-pulmonary artery pathway, the delivery system of the device sends the device to the arterial catheter along the pathway. This is a minimally invasive interventional therapy with the advantages of small wound area, high safety and quick recovery after operation. (2) The catheter stent of the device is provided with a unidirectional membrane. The unidirectional membrane can prevent the blood from the aorta from flowing to the pulmonary artery. However, when pulmonary arterial hypertension occurs, the blood can enter the aorta from the pulmonary artery through the catheter stent, thus reducing the pressure in the pulmonary artery.

BRIEF DESCRIPTION OF THE FIGURES In order to explain the technical scheme in the embodiments of the present invention more clearly, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained according to these drawings on the premise of no creative labor.

Figure 1 A schematic structural diagram of a delivery system for treating severe pulmonary hypertension caused by patent ductus arteriosus Figure 2 A schematic structural diagram of the delivery system Figure 3 A structural diagram of the catheter stent in a contracted state Figure 4 A schematic sectional structure diagram of catheter stent in a contracted state Figure 5 A schematic structural diagram of the catheter stent in a released state Figure 6 A schematic sectional structure diagram of catheter stent in a released state Components and their labels in the attached drawings are as follows: catheter stent 1, vascular stent 1-1, fixators at both ends 1-2, unidirectional film 1-3, plastic film 1-4 and developing coatings 1-5; delivery system 2, sheath tube 2-1, catheter 2-2, push rod 2-3, push block 2-4 and developing rings 2-5.

DESCRIPTION OF THE INVENTION In the following, the technical scheme of the present invention will be clearly and completely described through specific examples. Embodiment I The structure of the device for treating severe pulmonary hypertension caused by patent ductus arteriosus of the present invention is shown in Figure 1-6. The device comprises a catheter stent 1 and a delivery system 2. The catheter stent 1 comprises a vascular stent 1-1, fixators at both ends 1-2 and a unidirectional membrane 1-3. The vascular stent 1-1 is tubular, the side wall is a memory metal woven mesh. The inner wall is attached with a plastic film 1-4, and the plastic film 1-4 is a silicone rubber membrane. The silicone rubber membrane has good ductility and can follow the deformation of the vascular stent 1-1. Meanwhile, it can prevent blood from flowing through the stent gaps. The fixators at both ends are rings formed by connecting inverted V-shaped memory metals and are welded at both ends of the vascular stent 1-1. The tip parts of the fixators at both ends 1-2 are rounded corners. The rounded corners are attached with developing coatings 1-5. The developing coatings 1-5 are gold coatings. Under the irradiation of X-rays, the coatings will make the two ends of the catheter stent 1 be highlighted to help doctors clearly see the position of the catheter stent

1. The unidirectional membrane 1-3 is a funnel-shaped soft silica gel membrane with front and rear openings and is fixed in the vascular stent 1-1. When blood flows from aorta to pulmonary artery, the narrow end opening of the funnel-shaped soft silica gel membrane faces the blood flow direction. The unidirectional membrane 1-3 is compressed, thereby the narrow end opening 1s closed to prevent blood circulation. When blood flows from pulmonary artery to aorta during pulmonary hypertension, the large opening end of the funnel-shaped soft silica gel membrane faces the blood flow direction, thereby blood can pass through the unidirectional membrane 1-3 to reduce pulmonary artery pressure. The memory metal is nickel-titanium memory alloy. The nickel-titanium memory alloy can be deformed to its original state at 37°C and is suitable for human body. The hole projection shape of the mesh is rhombic, and the deformation direction of the mesh holes is that the rhombic holes extend transversely and shorten vertically. The diameter of the vascular stent 1-1 is enlarged and attached to the inner wall of the catheter. When the vascular stent 1-1 is compressed manually, it shortens transversely and extends vertically. The diameter of the vascular stent 1-1 becomes smaller and can be placed in the sheath tube 2-1 of the delivery system 2. The deformation direction of the fixators at both ends 1-2 are to tilt around with the bottom surface of the vascular stent 1- 1 as a circle.

After being released, the fixators at both ends 1-2 are deformed and clamped at both ends of the catheter to fix and stabilize the catheter stent 1. The delivery system 2 comprises a sheath tube 2-1, a catheter 2-2 and a push rod 2-3. The sheath tube 2-1 is a plastic tube with developing rings 2-5 at both ends.

The tail end of the sheath tube 2-1 is connected with a catheter 2-2. The catheter 2-2 is a vascular interventional catheter 2-2. The head end of the catheter 2-2 is connected with the sheath tube 2-1. A push block 2-4 is arranged at the head end of the push rod 2-3 for vascular intervention guide wire.

The push block 2-4 is a cylindrical plastic block, and the inner diameter is smaller than the sheath tube by 2-10.5mm.

The developing rings 2-5 are stainless steel rings.

Under X-ray, the plastic sheath tube 2-1 can see the inner catheter stent 1, and the developing rings 2-5 help to see the position of the sheath tube 2-1. The pushing process can be seen during pushing.

Embodiment I I The using method of the device for treating severe pulmonary hypertension caused by patent ductus arteriosus is as follows. (1) Establish femoral vein-inferior vena cava-right ventricle-pulmonary artery pathway. (2) Compress the diameter of the vascular stent 1-1, straighten the fixators at both ends 1- 2, and place the catheter stent 1 into the sheath tube 2-1. The funnel-shaped narrow end of the unidirectional membrane 1-3 points from the pulmonary artery to the right ventricular artery. (3) Under X-ray, the sheath tube 2-1 is guided into the femoral vein by using interventional guide wire until it reaches the pulmonary artery along the pathway.

Observe the developing rings 2-5 at both ends of the sheath tube 2-1 to judge whether the sheath tube 2-1 enters the right ventricular arterial catheter. (4) Withdraw the guide wire, send the push rod 2-3 into the catheter 2-2 at the end of the sheath tube 2-1, pinch the push rod 2-3, pull back the sheath tube 2-1, thereby the push block 2-4 leaves the catheter stent 1 in the right ventricular arterial catheter. (5) The memory metal of the catheter stent 1 is restored to its original state.

The vascular stent 1-1 is expanded radially outward, and the fixators at both ends 1-2 are tilted around and clamped at both ends of the right ventricular arterial catheter. (6) Exit the delivery system 2 from the pathway.

The above-mentioned embodiment is only a description of the preferred embodiment of the present invention, and does not limit the concept and scope of the present invention.

On the premise of not departing from the design concept of the present invention, various modifications and improvements made by ordinary engineers and technicians in the field to the technical scheme of the present invention shall fall into the protection scope of the present invention, and all the technical contents requested for protection of the present invention have been recorded in the technical requirements.

Claims (8)

CLAIMS:

1. À device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus, characterized by comprising a valve stent and a delivery system; the valve stent comprises a vascular stent, fixators at both ends and a unidirectional membrane; the vascular stent is tubular, the side wall is a memory metal woven mesh, and the inner wall is attached with a plastic film; the fixators at both ends are rings formed by connecting inverted V-shaped memory metals and are welded at two ends of the vascular stent; the tip parts of the fixators at both ends are rounded corners, and developing coatings are attached to the rounded corners; the unidirectional membrane is a funnel-shaped biological valve with front and rear openings and is fixed in a vascular stent; the delivery system comprises a sheath tube, a catheter and a push rod; the sheath tube is a plastic tube, and two ends of the sheath tube are provided with developing rings; the tail end of the sheath tube is connected with the catheter; the catheter is a vascular interventional catheter, and the head end is connected with a sheath tube; a push block is arranged at the head end of the push rod for vascular intervention guide wire; the push block is a cylindrical plastic block, and the inner diameter is smaller than the sheath tube by 0.5mm.

2. The device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus according to claim 1, characterized in that the memory metal is nickel-titanium memory alloy.

3. The device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus according to claim 1, characterized in that the hole projection shape of the mesh is rhombic, and the deformation direction of the mesh holes is that the rhombic holes extend transversely and shorten vertically.

4. The device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus according to claim 1, characterized in that the deformation direction of the fixators at both ends is to tilt around with the bottom surface of the vascular stent as a circle.

5. The device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus according to claim 1, characterized in that the plastic film is silicone rubber membrane and the developing coatings are gold coatings.

6. The device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus according to claim 1, characterized in that the developing rings are stainless steel rings.

7. The using method of the device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus according to claim 1 to 6, characterized by comprising the following steps: (1) establish femoral vein-inferior vena cava-right ventricle-pulmonary artery-arterial catheter-descending aorta pathway; (2) compress the diameter of the vascular stent, straighten the fixators at both ends, and place the catheter stent into the sheath tube; (3) under X-ray, the sheath tube is guided into femoral vein by using interventional guide wire until it reaches the pulmonary artery along the pathway, and observe the developing rings at both ends of the sheath tube to judge whether the sheath tube enters the arterial catheter; (4) withdraw the guide wire, send the push rod into the catheter at the end of the sheath tube, pinch the push rod, pull back the sheath tube, thereby the push block leaves the catheter stent in the arterial catheter; (5) the memory metal of the catheter stent is restored to its original state, the diameter of the vascular stent is expanded outward, and the fixators at both ends are tilted around and clamped at both ends of the arterial catheter; (6) exit the delivery system from the pathway.

8. The using method of the device for treating severe pulmonary arterial hypertension caused by patent ductus arteriosus according to claim 7, characterized in that the funnel- shaped narrow end of the unidirectional membrane points from the pulmonary artery to the aorta.