Visual-visual guide wire for accurately positioning artery opening lesion stent

Abstract

The utility model provides an audio-visual guide wire for accurately positioning an artery opening lesion stent, which is characterized in that a second mark point and a first mark point which are embedded in the guide wire are sequentially arranged behind the head end of the guide wire at intervals, and the first mark point and the second mark point are annular non-X-ray-transmitting mark points; a Doppler ultrasonic probe is embedded in the first mark point, and the second mark point is located at the sampling volume of the Doppler ultrasonic probe; the distance between the first marking point and the second marking point is 3mm, and a near-end mark of the stent is implanted between the first marking point and the second marking point. According to the utility model, the second marking point is arranged at a certain distance from the head end of the guide wire, the first marking point is arranged behind the second marking point, and the ultrasonic transducer probe is embedded in the first marking point, so that the ultrasonic transducer probe not only emits pulse ultrasonic waves, but also receives reflected signals of moving blood cells (sampling volume) in front of the ultrasonic transducer probe to the pulses; therefore, the lesion position can be quickly and accurately positioned.

Description

Technical Field

[0001] The utility model relates to a medical device, in particular to a visual and audible guide wire used for accurate positioning of an arterial ostium lesion stent. Background Art

[0002] Stent implantation is the main treatment method of interventional surgery. When dealing with the special site of stenosis at the opening of the coronary artery or renal artery, in addition to strict requirements on the geometric dimensions such as the diameter and length of the selected stent, it is more important and critical to accurately position the stent during the operation; the basic principle of accurate stent positioning is to ensure that the stent completely covers the lesion and avoid the proximal end of the stent from unnecessarily extending too much into the aortic lumen. However, practice has shown that the currently used methods or technologies and various improvement measures and patent solutions proposed to address the defects are difficult to achieve perfect and accurate positioning of the stent, thus affecting the therapeutic effect of stent implantation and may lead to surgical complications.

[0003] Aorta-coronary artery ostium lesions refer to lesions at the junction of the ascending aorta, the left main coronary artery (LM) and the right coronary artery (RCA), within 3mm of the coronary artery ostium; the LM originates from the left coronary sinus at the root of the aorta, with a diameter of 3-6mm and a length of about 5-20mm; in most cases, there are two branches, the left anterior descending artery (LAD) and the left circumflex artery (LCX); in 30% of cases, the LM is divided into three branches, the LAD, LCX and intermediate branch; in 2% of cases, the LM is divided into more than three branches; the anatomy and distribution of the RCA are relatively simple.

[0004] Left main coronary artery disease (LMCAD) is a high-risk complex lesion. Plaque rupture causes myocardial infarction that involves the entire left ventricle and the inferior wall of the right ventricle with left coronary dominant anatomical structure. It is easy to cause ventricular fibrillation, cardiac arrest or cardiogenic shock, with serious consequences and extremely poor prognosis. It needs to be taken seriously and treated early. According to statistics, about 4-6% of patients undergoing coronary angiography have LMCAD and often have branch lesions; LMCAD is divided into opening lesions (accounting for 8-13%), body lesions (accounting for 32-47%) and terminal bifurcation lesions (accounting for 44-62%, including LAD or LCX openings) and full-length lesions; LMCAD opening lesions are the most easily overlooked, and the starting part extends directly from the aortic wall with a wall thickness of 2-4mm. The middle layer of the aortic wall is rich in smooth muscle cells and elastic fiber tissue. Simple balloon dilatation is prone to elastic recoil during percutaneous coronary intervention (PCI), so stent implantation is required for prevention. The risk of coronary angiography in patients with LMCAD is also high, which may lead to heart failure, cardiogenic shock, or even cardiovascular collapse and death; the standard practice of coronary angiography is: ① Carefully operate the angiography catheter or guide catheter in place to avoid damaging the LM opening. ② Closely observe the changes in the pressure curve throughout the process to prevent pressure entrapment from causing severe myocardial ischemia. ③ Try to choose 1-2 key positions to fully expose the lesion, avoid excessive contrast agent injection or one-time contrast agent injection for too long. It should be noted that sometimes catheter stimulation causes spasm or is misjudged as negative remodeling due to angle problems. The so-called "stenosis" seen during angiography is not necessarily true stenosis. On the contrary, it is possible that the so-called "non-stenosis" due to the lack of normal reference segments in diffuse LM lesions is actually true stenosis; misjudgment should be avoided as much as possible and it is best to prevent it from happening. At present, intravascular ultrasound (IVUS) is the most effective method for diagnosing LMCAD. IVUS can correctly identify and judge intravascular conditions such as opening lesions, negative remodeling, plaque characteristics, and true vascular size. Domestic and foreign guidelines recommend IVUS to formulate treatment strategies. LMCAD can be treated with medication, PCI or coronary artery bypass grafting (CABG). PCI or CABG improves patient survival compared with medication alone. PCI is increasingly used, constantly challenging CABG as the standard treatment option.

[0005] The major challenge facing PCI is the precise positioning and release of stents for ostial lesions, especially LMCAD. PCI of ostial lesions is high-risk, with poor surgical success rate and long-term clinical prognosis. The treatment principle for achieving ideal results by implanting stents in ostial lesions is to completely cover the stenotic lesions, avoid unnecessary extension of the proximal end of the stent into the aortic lumen, and prevent the stent from shifting during release; if the proximal end of the stent is too far away from the ostium, it cannot completely cover the ostial lesion, the stenosis is not relieved, and the elastic retraction of the vessel and the displacement of the plaque may lead to restenosis at the ostium and in the stent, and at the same time increase the chance of acute thrombosis at the ostium during the PCI perioperative period and endanger the patient's life; it is urgent to implant the stent to cover the lesion for remedy. If the proximal end of the stent protrudes too much from the aortic lumen, the consequences are also not optimistic. It is not conducive to endothelial cell coverage of the stent to achieve endothelialization and increase the risk of thrombosis. It will also increase the difficulty of the guide catheter entering the coronary artery and cause the failure of the second PCI. It also has the disadvantages of hindering aortic blood flow and hindering transcatheter aortic valve intervention (TAVI).

[0006] The difficulties faced by LMCAD during PCI are as follows: ① The location is critical. Once a dissection occurs at the opening, the patient is at high risk of sudden death. It extends downward to the acute occlusion of the coronary artery branch vessels and extends in reverse to the aortic wall. ② Due to concerns and concerns about blocking the opening, the catheter is suspended for angiography, less contrast agent enters the coronary artery, and the imaging is unclear and may be poor, which affects the accurate evaluation of the lesion. ③ It is difficult to choose the angiography position / angle and it varies from person to person. The opening cannot be fully displayed. Projection reduction or overlap can also lead to misjudgment. ④ PCI operation must be rapid. Balloon and stent pressurization or guide catheter blocking the opening for too long significantly increases the risk. ⑤ The opening lesion is rich in elastic tissue, easy to retract and often accompanied by calcification, and the restenosis rate is high. ⑥ Overlong stents may protrude from the opening or involve the terminal bifurcation, which complicates the treatment strategy. ⑦ Breathing and cardiac activity can easily cause stent displacement. Accurate positioning of the stent in the opening lesion is time-consuming, the operator and patient are exposed to increased radiation, and long-term blood flow obstruction causes myocardial ischemia and excessive use of contrast agents, which increases the incidence of complications.

[0007] In order to solve the problem of accurate positioning of stents for ostial lesions during clinical PCI, domestic and foreign scholars have proposed some technical solutions or application of operation skills. The main methods are: ① Select a suitable body position to fully expose the relationship between the upper and lower edges of the LM opening and the space in the aortic sinus; usually, the tangent position such as the left anterior oblique head position exposes the LM opening most clearly, and if necessary, add the front head position or the right anterior oblique head position, the left anterior oblique head position, etc. ② When positioning the stent, the guide catheter is slightly withdrawn to clearly show whether the lesion at the opening is completely covered by the stent. ③ Choose a tubular or annular stent with strong support to reduce elastic retraction. ④ Emphasize the positioning principle that the stent protrudes 1-2mm into the aorta from the LM opening. When the proximal landmark of the stent is flush with the lower edge of the LM opening, it basically meets the requirement of completely covering the lesion without affecting the catheter's re-entry into the LM. However, it should be emphasized that all stents have two landmarks visible in perspective to indicate the proximal and distal edges of the stent. However, the distance between the landmarks of different brands and the edge of the stent varies. Some landmarks are on the inside of the stent, while others are on the outside of the stent, with a difference of up to 1-2mm. This must be carefully considered when accurately positioning the stent. ⑤ After the stent is released, the balloon is withdrawn 2-3mm into the aorta, and high-pressure expansion is performed for a short time. If necessary, a larger diameter short balloon is used for further high-pressure expansion to ensure that the stent is fully expanded and well adhered to the wall, and the stent mouth is shaped like a "trumpet". ⑥ For severe calcified lesions, pretreatment methods such as cutting balloon, directional atherectomy or atherectomy should be used first to obtain a larger lumen area before stent placement. ⑦Multi-position angiography evaluation is required during the operation. It is best to perform IVUS examination to obtain satisfactory results, which will help to accurately determine the LM opening position, select the appropriate size stent, and understand the stent adhesion condition.

[0008] In order to solve the pain point that the above conventional technologies are still not accurate in positioning the stent in the ostial lesions, some surgeons place IVUS transducers at the lesion site at the same time, and use IVUS images as a reference to accurately position the stent in real time. The disadvantage is that a larger diameter guide catheter is required, and it is highly dependent on the surgeon's ability to recognize IVUS images. In addition, domestic and foreign scholars are also actively exploring some special methods or utility model related devices to solve the problem of accurate stent positioning, which are mainly divided into two aspects: one is the Szabo technology and Draw-back technology and their improved methods for non-ostial lesions; the other is the intra-aortic floating guidewire technology and special device positioning system for aortic ostial lesions. The details are as follows: ① Szabo technique is also known as tail wire or companion guide wire technique. First, two guide wires are implanted in the main branch and branch vessels respectively, and the branch opening lesion is pre-dilated by balloon. The stent to be implanted in the branch opening is placed on the branch guide wire through the central cavity. The operator's fingers pinch most of the stent except the proximal end of the stent in a ring shape. At the same time, the assistant uses a pressure pump to expand the stent balloon with a low pressure of 200-300kPa. The mesh of the last row of grooves at the proximal end of the stent is expanded, and the tail end of the companion guide wire in the main branch vessel is passed through this mesh. The two guide wires are arranged and fixed, and the stent is delivered to the branch opening lesion. At this time, the companion guide wire has a entanglement effect on the stent, which can prevent the proximal end of the stent from remaining too much in the main branch vessel and affecting the blood flow of the main branch vessel, and can also avoid the distal end of the stent from entering the branch vessel too much and affecting the inability to fully cover the branch vessel opening lesion. The disadvantage is that since the proximal mesh of the stent is pre-treated and expanded, it may cause the stent and the internal balloon to loosen, increase the risk of stent unloading, and the operation is more complicated, and it is more difficult to wrap the guide wire and push the stent. ② Draw-back technology, also known as stent-balloon kissing technology, relies on the blocking effect of the expansion balloon to accurately position the stent. The disadvantage is that the balloon and stent need to be delivered at the same time, and a guide catheter with a larger outer diameter is required, which increases the difficulty of operation and surgical risks. The balloon expansion damages non-target blood vessels. There is still a gap between the balloon and the proximal end of the stent, which may cause the stent to be positioned deeper into the target blood vessel than expected, resulting in failure to completely cover the opening lesions. ③ Intra-aortic floating guide wire technology, including improved floating double guide wire or floating balloon technology, can stabilize the guide catheter to varying degrees and play a role in opening positioning; the disadvantage is that if the guide catheter is pressed against the coronary artery opening with too little force, the system will be unstable, and if too much force is used, the guide wire may cut the aorta and coronary artery openings and damage the blood vessels. ④ The positioning system of the coronary artery opening Ostialpro stent and its improvement, nickel-titanium memory alloy assists in achieving precise positioning of the stent, and the push rod is designed with a set of fan-shaped devices, which first push the stent into the distal end of the opening lesion, and then push the fan-shaped device out of the guide catheter, like an electric fan blade, close to the aortic sinus at the coronary artery opening, and the four fan blades with platinum developing points support the positioning feet to form a developing surface facing the aortic wall. The stent is withdrawn so that its proximal developing point falls inside it, achieving precise positioning of the stent.The disadvantages are that the positioning pin is prone to damage the aortic wall and requires a larger outer diameter guide catheter.

[0009] Based on the above analysis, there are still many problems to be solved in the existing technologies or methods for accurate positioning of stents for ostial lesions. Either the structure or the device itself has defects, the operation is complicated and difficult to master, or the operation is time-consuming and laborious, and the treatment cost is high. Therefore, it is necessary to continue to develop more convenient, safe, effective and lower-cost accurate positioning technology for stents for ostial lesions. Relevant Chinese patents in recent years include:

[0010] ① Bifurcated guidewire for locating the coronary artery opening when the stent is released (CN 215994401 U): There is a developing mark at the bifurcation of the guide wire at the distal end, and a long guidewire and a short guidewire are provided. The guide wire is sent to the coronary artery opening, the long guidewire is sent into the coronary artery, and the short guidewire is sent into the coronary sinus. The guidewire bifurcation is just stuck at the edge of the coronary artery to mark the LM opening and is used to locate the stent; but it obviously has the same disadvantage as the floating guidewire technology in the aorta, that is, it is difficult to grasp the degree of force of the guidewire bifurcation stuck at the edge of the coronary artery, so it is difficult to accurately locate the stent.

[0011] ② Special guiding catheter for left main coronary artery ostial lesions (CN 206924237 U): It mainly solves the problem of guide catheter being stuck in the LM opening. A guidewire channel tube is arranged inside the wall of the guide catheter, into which a guidewire can be inserted and sent into the aorta to form a fold around the coronary artery opening. There are guidewire supports from two different directions to increase the stability of the guide catheter. It obviously has similar defects to the floating guidewire technology in the aorta, and the outer diameter of the guide catheter needs to be increased.

[0012] ③ A precise positioning system for stents of coronary artery ostial lesions (CN 219557688 U): It includes a mounting seat, a guide wire fixing seat, a first through hole, a second through hole, two clamping pieces, a driving assembly, a slide groove, a slider and many other components, and relies on in vitro operation to complete precise stent positioning; the disadvantages are that the structure is very complex, the learning curve is very long, and the effect is uncertain.

[0013] ④ Precision positioning vascular stent device (CN 212186774 U): A new stent positioning system based on a computer-aided design model. The process uses laser cutting of positioning feet and welding of nickel-titanium alloy to improve the delivery wire, and better mechanical properties are obtained by changing the thick and thin wire structure. The concept is similar to the ostialpro stent positioning system, so its shortcomings are also the same. ⑤ Coronary artery ostium stent precision positioning system (CN

[0014] 106491252A): It includes a guide wire, a stent and a three-chamber two-balloon stent delivery device. The rear-end positioning balloon first expands the shaft tube, opens the valve at the expansion chamber, and expands the pre-expansion balloon, thereby implanting the stent. It is obvious that the structure is very complex and requires a guide catheter with a larger outer diameter.

[0015] Lesions at the aorta-renal artery opening refer to lesions at the junction of the left and right renal arteries (RA) and the abdominal aorta, within 3 mm of the renal artery opening. Renal artery stenosis (RAS) can cause secondary hypertension, paroxysmal pulmonary edema, ischemic nephropathy, renal insufficiency and uremia. The two common causes of RAS are: atherosclerosis accounts for 70-80%, and fibromuscular dysplasia accounts for 20-30%; RAS can be bilateral, but usually starts on one side first, leading to reduced perfusion pressure, renal ischemia, increased renin release, and increased blood pressure. Further reduction in perfusion pressure will cause the kidneys to shrink, the filtration rate to decrease, and even stop producing urine; persistent severe ischemia will cause kidney atrophy, glomerular sclerosis, focal necrosis and multiple cysts; if both sides of RAS continue to progress, severe renal ischemia can gradually develop into end-stage renal disease. Angiography is the "gold standard" for diagnosing RAS, which can observe the exact location, degree and morphology of stenosis. The interventional treatment process for RAS ostial lesions is: when the stent is roughly in place, the guiding catheter should be slightly withdrawn to allow the proximal end of the stent to extend 1-2mm into the abdominal aorta lumen. After satisfactory positioning, the stent is released, the balloon is withdrawn, or the high-pressure balloon is further expanded to make the stent take a "trumpet" shape. Obviously, in the interventional surgery for RAS ostial lesions, there is also the problem of inaccurate stent positioning, which faces the same difficulties as PCI surgery for coronary artery ostial lesions.

[0016] Clinically, there is an urgent need for a stable, reliable, safe and effective device to assist in the precise positioning of stents for vascular ostial lesions. The difficulty in implanting stents for ostial lesions lies in how to accurately determine the location of the arterial ostium. Since the coronary artery presents a three-dimensional spatial structure, there are inevitably blind spots and omissions in judging the location of the ostium from the two-dimensional projection of coronary angiography, and it is often necessary to perform repeated angiography at multiple angles and in different positions for comprehensive judgment. Even so, the precise positioning and release of stents for ostial lesions still need to consider special anatomical issues. In addition to carefully analyzing the characteristics of the lesions, selecting treatment methods and strategies, and skilled operation, improvements in related technologies and instruments are also essential.

[0017] The Doppler effect is an important physical phenomenon. When there is relative motion between the transmitting wave source and the reflector, the wavelength or frequency of the echo received by the receiver will change, resulting in the so-called "frequency shift phenomenon". The blood in the blood vessels is a flowing object, and the red blood cells in the blood flow can act as reflectors. By sending ultrasonic pulses to the blood flow area, the Doppler effect will also occur between the ultrasonic source and the red blood cells in the blood that are relatively moving. When the blood flow is moving toward the ultrasonic source, the wavelength of the reflected wave is compressed and the frequency increases, while when the blood flow is moving away from the ultrasonic source, the wavelength of the reflected wave becomes longer and the frequency decreases; therefore, the increase or decrease in the wavelength of the reflected wave and the decrease or increase in the frequency shift correspond to different blood flow directions; the blood flow direction can be determined based on the positive or negative wavelength or frequency shift between the ultrasonic reflected wave and the transmitting wave, and the degree of increase or decrease in the frequency shift is positively correlated with the blood flow velocity. Since the blood flow velocity of 10m / s is much lower than the ultrasonic velocity of 1540m / s, the blood flow velocity can be measured based on the wavelength / frequency shift in the direction of sound wave propagation. Pulse spectrum Doppler (PW) and continuous spectrum Doppler (CW) use frequency shift curves to determine the direction and velocity of blood flow. After the blood flow spectrum signal is encoded by color grayscale, the blood flow direction is marked with red and blue colors, and the blood flow velocity is marked with brightness. It is superimposed and displayed on a two-dimensional image in real time, and there is also an audio spectrum output, which forms a color Doppler ultrasound blood flow (CDFI) image; CDFI has both a two-dimensional ultrasound structural image and hemodynamic information. The horizontal axis of the spectrum graph represents time, and the vertical axis represents frequency shift. The horizontal line represents zero frequency shift, also known as the baseline. The positive red frequency shift on the baseline indicates that the blood flow direction is toward the probe, and the negative blue frequency shift under the baseline indicates that the blood flow direction is away from the probe. Bright or dim colors represent fast or slow blood flow; bidirectional blood flow may be detected at the bifurcation of blood vessels, which is a mixture of red, blue and green primary colors. In clinical practice, CDFI is used to non-invasively detect hemodynamic information such as blood flow direction, velocity, nature, pathway and time in the heart and blood vessels, which plays an important auxiliary role in the diagnosis of cardiovascular diseases.

[0018] In 1967, a continuous Doppler probe installed at the tip of a cardiac catheter was used to record aortic blood flow velocity for the first time; in 1969, a catheter equipped with a continuous Doppler probe detected blood flow signals in human coronary arteries at the root of the aorta; in 1990, a Doppler guide wire was first inserted into the coronary artery to measure blood flow velocity; later, with the development of miniaturization technology that integrates the transducer into the guide wire, intracoronary Doppler ultrasound examinations were routinely carried out at home and abroad; the FlomapⅡ intravascular Doppler blood flow velocity recorder produced by Cardiometric Company in the United States is often used to insert the coronary artery through the guide catheter. The FloWire guide wire with a Doppler probe is inserted into the vein. It is 1750mm long and 0.36-0.46mm in diameter. The soft tip is straight or prefabricated into a 30-degree J shape. A 12 or 15MHz high-frequency acoustic piezoelectric crystal transducer is placed 15-30mm from the tip, which can transmit and receive ultrasonic signals. The pulse repetition frequency is 16-94kHz, the pulse duration is 0.83μs, and the sampling delay is 6.5μs. The transducer transmits ultrasonic discrete angles of 28 degrees, the sampling volume is 5.2mm from the tip, the transverse diameter is 2.25mm, and the longitudinal diameter is 0.65mm. Therefore, it should be noted that the guide wire can only detect the direction and speed of blood flow in a narrow range in the target blood vessel. The exact location is a dot-shaped area 5mm in front of the ultrasonic transducer probe and 2.25×0.65mm in width and thickness. The direction of blood flow is determined by the positive and negative Doppler frequency shifts generated between the transmission frequency and the reflection frequency; the corresponding blood flow velocity is calculated based on the frequency shift, and a blood flow velocity of up to 4m / s can be recorded. The guide wire is repeatedly adjusted to allow the probe and its tip to pass through the relevant vascular target lesions smoothly and reach the appropriate position 20-30mm from the distal end. The blood flow signal from the blood vessel is analyzed spectrally using the fast Fourier transformation method; the ideal Doppler continuous blood flow spectrum signal should present a clear, stable, relatively dense, repeatable and regular envelope in each cardiac cycle, and automatically calculate blood flow parameters in real time; the Doppler sound can be clearly heard through the setting. The main functions of measuring coronary Doppler blood flow velocity in clinical practice are: ① evaluating the gold standard for microvascular function; ② judging whether critical lesions are involved in myocardial ischemia, judging the target vessels that multi-vessel lesions affect myocardial ischemia, and for tandem lesions of multiple lesions in a single vessel, gradually withdrawing from the distal end of the stenosis and continuously measuring to determine the target lesion that most affects myocardial ischemia; ③ evaluating the coronary blood flow reserve function by injecting drugs to induce hyperemia; ④ understanding the advantages and disadvantages of collateral circulation; ⑤ real-time evaluation of the efficacy of PCI. Coronary Doppler blood flow velocity indicators include the average peak blood flow velocity, the ratio of diastolic and systolic blood flow velocity, and the corresponding target blood flow calculated by the formula.

[0019] Doppler guidewires have been used in many clinical situations, but they are almost all used in diagnosis, specifically to measure coronary blood flow velocity and calculate intravascular blood flow; and due to the inherent defects of this examination and the rapid progress of other coronary artery functional technologies, there are few opportunities for Doppler guidewires to be used in clinical practice. The main problems with Doppler guidewires are: invasiveness; high cost of one-time use; prone to a certain degree of signal drift; inferior control performance to conventional guidewires, and it is difficult to achieve coaxial alignment, accurate positioning and position fixation, and the probe is suspended in the lumen and does not touch the vessel wall.

[0020] In recent years, with the progress in welding technology, guide wire materials, grinding manufacturing, etc., the research and development of guide wires for various purposes and improved guide wire performance has flourished. There are now sensors on the market that can simultaneously measure the pressure, velocity and temperature in the coronary artery, and can also be integrated into the guide wire tip with a diameter of only 0.36mm alone or in a mixed manner; the recently developed application of fiber optic transducers and their integration into guide wires significantly improves the control performance and significantly reduces signal drift; the new intelligent sensing guide wire can more easily navigate and overcome the difficulty of blind insertion of chronic occlusive lesions.

[0021] In view of the continuous improvement of guide wire performance for better maneuverability and the development of related technology reserves for better opportunities, combined with the urgent clinical demand for accurate positioning of stents for arterial ostial lesions; the utility model is based on the basic principle of ultrasonic Doppler guide wire to accurately determine the direction of blood flow, cleverly utilizing the physiological characteristics that the blood flow directions of the aorta and its branch arteries are exactly opposite, the perfect combination of the two to address the defects of the existing technology, and provide a visual and audio guide wire and device for accurate positioning of stents for arterial ostial lesions. Utility Model Content

[0022] The utility model provides a visual and audio guide wire for accurate positioning of an arterial ostial lesion stent, characterized in that a second marking point and a first marking point embedded in the guide wire are sequentially arranged at intervals behind the guide wire head end, the first marking point and the second marking point are both annular X-ray-proof marking points, a Doppler ultrasonic probe is embedded in the first marking point, and the second marking point is located at the ultrasonic sampling volume in front of the Doppler ultrasonic probe;

[0023] The distance between the first marking point and the second marking point is 3 mm, and the area between the first marking point and the second marking point is used for marking the proximal end of the implanted stent.

[0024] Furthermore, each width of the first marking point and the second marking point is 2 mm.

[0025] Furthermore, the second marking point is 40 mm or 60 mm away from the guide wire tip.

[0026] Furthermore, the guide wire has a diameter of 0.36 mm and a length of 1750 mm.

[0027] The utility model sets a second marking point at a certain distance from the guide wire head end, sets a first marking point behind the second marking point and embeds an ultrasonic transducer probe in the first marking point. The ultrasonic transducer probe here not only transmits pulsed ultrasonic waves, but also receives reflected signals of these pulses from moving blood cells (sampling volume) in front of it, thereby locating the lesion position more quickly and accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 A schematic diagram of a visual and audio guide wire for precise positioning of a stent for arterial ostial lesions provided by the utility model;

[0030] Figure 2 It is a three-dimensional diagram of the local structure of the guide wire of the utility model;

[0031] Figure 3 This is a schematic diagram of using the guide wire of the utility model to accurately locate the lesion of the left main trunk of the coronary artery in Example 1;

[0032] Figure 4 This is a schematic diagram of using the guide wire of the utility model to accurately locate the lesion of the renal artery opening in Example 2. DETAILED DESCRIPTION

[0033] In the following description, a large number of specific details are given to provide a more thorough understanding of the utility model. However, it is obvious to those skilled in the art that the utility model can be implemented without one or more of these details. In other examples, in order to avoid confusion with the utility model, some technical features known in the art are not described.

[0034] In order to thoroughly understand the present invention, detailed steps and detailed structures will be presented in the following description to illustrate the technical solution of the present invention. The preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention may also have other implementations.

[0035] Reference Figure 1-2As shown, the utility model provides a visual and audio guide wire 100 for accurate positioning of an arterial ostial lesion stent. The diameter of the guide wire 100 is 0.36 mm and the length is 1750 mm. Assume that the front end of the guide wire 100 is the head end (i.e. Figure 1 The left end), the other end is the tail end (i.e. Figure 1 right end).

[0036] A second marking point 120 embedded in the guide wire 100 is provided 40 mm or 60 mm away from the tip of the guide wire 100, and a first marking point 110 embedded in the guide wire 100 is also provided 3 mm behind the second marking point 120, and a proximal end mark for implanting the stent is provided between the first marking point 110 and the second marking point 120, and a Doppler ultrasonic probe 111 is embedded in the first marking point 110. The first marking point 110 and the second marking point 120 are both annular radiopaque marking points (or marking rings) with a width of 2 mm. Since the spacing between the first marking point 110 and the second marking point 120 is 3 mm, the center distance between the first marking point 110 and the second marking point 120 is 5 mm, so that the second marking point 120 is located at the ultrasonic sampling volume in front of the Doppler ultrasonic probe 111.

[0037] The mature products currently on the market and in clinical use are the American Cardiometrics FloMapⅡ ultrasonic diagnostic instrument and the matching FloWire Doppler guide wire. The FloWire Doppler guide wire is 1750mm long and 0.36mm in diameter, with only one marking point, which is an ultrasonic transducer probe installed 30mm from the tip of the guide wire. Based on the FloWire Doppler guide wire, this application takes into account special application scenarios, sets a second marking point 120 40mm or 60mm from the tip of the guide wire, sets a first marking point 110 5mm behind the second marking point 120 and embeds an ultrasonic transducer probe (i.e., Doppler ultrasonic probe 111), which both emits pulsed ultrasonic waves and receives the reflection signals of these pulses from the moving blood cells (sampling volume) 5mm in front of it (5mm is the center distance between the first marking point 110 and the second marking point 120).

[0038] The utility model relates to real-time monitoring of the frequency shift of blood flow in the target blood vessel based on the Doppler effect. The blood flow is positively or negatively shifted when facing or facing away from the probe, and is displayed in a visual and audible spectrum and sound. The guide wire is sent to the branch artery and then withdrawn to the aorta, and the physiological characteristics of the opposite blood flow directions are used. When the reversal point of the blood flow frequency shift is detected, the guide wire is fixed, and at this moment, the second marking point 120 is located at the opening position of the branch artery. The proximal mark of the stent is adjusted to fall between the first marking point 110 and the second marking point 120, and the "single track sign" is presented through multi-position projection to complete the precise positioning of the stent. It has the characteristics of clear principle, simple structure, easy operation, and no need for angiography.

[0039] Example 1: Guide wire accurately locates the ostial lesion of the left main coronary artery

[0040] like Figure 3 As shown, on the basis of maintaining the function of the guide wire track, the guide wire 100 is delivered to the coronary artery 3 via the radial artery or femoral artery, and then slowly withdrawn to the ascending aorta 1;

[0041] The Doppler ultrasonic probe 111 at the first marking point 110 monitors the frequency shift of blood flow in the two target blood vessels in real time, and cleverly utilizes the physiological characteristics that the blood flow 2 in the ascending aorta and the blood flow 4 in the coronary artery face the Doppler ultrasonic probe 111 in opposite directions. The ascending aorta blood flow 2 facing the Doppler ultrasonic probe 111 is displayed as a positive frequency shift, while the coronary artery blood flow 4 facing away from the Doppler ultrasonic probe 111 is displayed as a negative frequency shift, and the characteristics of different frequency shift directions are displayed in a spectrum diagram and audio-visual manner;

[0042] Move the guide wire. When the Doppler ultrasonic probe 111 detects the reversal point of the blood flow frequency shift, it indicates the location of the left main trunk opening lesion plaque 5, which overlaps with the sampling volume 5 mm in front of the ultrasonic probe (i.e., the second marking point 120). Using this as a mark, the stent is inserted along the guide wire 100. Without using contrast agents and only requiring multi-angle projection, repeated adjustments are made to confirm that the proximal mark of the stent falls exactly between the first marking point 110 and the second marking point 120 and presents a "single-track sign", so that the stent can be accurately positioned. This ensures that the stent completely covers the lesion and prevents the proximal end of the stent from extending too much into the aortic lumen.

[0043] Example 2: Precise positioning of renal artery ostium lesions using a guide wire

[0044] like Figure 4As shown, on the basis of maintaining the function of the guide wire track, the guide wire 100 must be sent to the renal artery 23 through the femoral artery, and then slowly withdrawn to the abdominal aorta 21; the Doppler ultrasonic probe 111 monitors the frequency shift of blood flow in the target blood vessels at these two locations in real time, and the abdominal aorta blood flow 22 facing the Doppler ultrasonic probe 111 is displayed as a positive frequency shift, while the renal artery blood flow 24 facing away from the Doppler ultrasonic probe 111 is displayed as a negative frequency shift. The physiological characteristics of the blood flow 22 in the abdominal aorta and the blood flow 4 in the renal artery facing the Doppler ultrasonic probe 111 in opposite directions are cleverly utilized to form a spectrum diagram. The sound and audio-visual display show the different characteristics of frequency shift changes in different directions. When the Doppler ultrasound probe 111 monitors and identifies the blood flow frequency shift reversal point as the second marking point 120 in real time, it overlaps with the position of the renal artery opening lesion 25. The stent is then sent in along the guide wire. Without the need for contrast agent, only multi-angle projection is required. Repeated adjustments confirm that the proximal mark of the stent falls exactly between the first marking point 110 and the second marking point 120 of the guide wire, showing a "single-track sign", and the stent can be accurately positioned. This ensures that the stent completely covers the lesion, while preventing the proximal end of the stent from extending too much into the abdominal aorta lumen.

[0045] The advantages of the utility model are:

[0046] 1. Accurate positioning: Through the built-in Doppler ultrasonic probe, the utility model can monitor the blood flow frequency shift in the target blood vessel in real time, and accurately locate the position of the arterial opening lesion by means of the physiological characteristics of the blood flow direction. Through the visual and audio display of the spectrum graph and sound, the operation is more intuitive and convenient.

[0047] 2. Easy to operate: Compared with traditional methods, this utility model does not require the use of contrast agents, and can complete the precise positioning of the stent only through multi-angle projection and simple guide wire operation. This not only reduces the difficulty of operation, but also reduces the medical risks of patients.

[0048] 3. High safety: Through precise positioning, the utility model can ensure that the stent completely covers the lesion, while preventing the proximal end of the stent from extending too far into the aorta or abdominal aorta lumen, thereby reducing the risk of postoperative complications.

[0049] 4. Wide scope of application: The utility model is not only applicable to the precise positioning of the left main coronary artery ostial lesions, but also to the precise positioning of other arterial ostial lesions such as the renal artery ostial lesions. Its wide applicability makes the utility model have higher practical value in clinical applications.

[0050] The above describes the preferred embodiments of the utility model. It should be understood that the utility model is not limited to the above-mentioned specific implementation methods, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the utility model without departing from the scope of the technical solution of the utility model, or modify them into equivalent embodiments of equivalent changes, which does not affect the essential content of the utility model. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the utility model without departing from the content of the technical solution of the utility model still falls within the scope of protection of the technical solution of the utility model.

Claims

1. A visual and audible guide wire for precise positioning of a stent for an arterial ostial lesion, characterized in that: A second marking point (120) and a first marking point (110) are sequentially arranged at intervals behind the head end of the guide wire (100), and are embedded in the guide wire (100); the first marking point (110) and the second marking point (120) are both annular X-ray-proof marking points; a Doppler ultrasonic probe (111) is embedded in the first marking point (110); and the second marking point (120) is located at an ultrasonic sampling volume in front of the Doppler ultrasonic probe (111); The distance between the first marking point (110) and the second marking point (120) is 3 mm, and the area between the first marking point (110) and the second marking point (120) is used for marking the proximal end of the implanted stent.

2. A visual and audible guide wire for accurate positioning of an arterial ostial lesion stent as claimed in claim 1, characterized in that: The width of each of the first marking point (110) and the second marking point (120) is 2 mm.

3. A visual and audible guide wire for accurate positioning of an arterial ostial lesion stent as claimed in claim 1, characterized in that: The second marking point (120) is 40 mm or 60 mm away from the tip of the guide wire (100).

4. A visual and audible guide wire for accurate positioning of an arterial ostial lesion stent as claimed in claim 1, characterized in that: The guide wire (100) has a diameter of 0.36 mm and a length of 1750 mm.

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