Coronary diagnostic assembly with guidewires to assist cardiac stimulation and measure fractional flow reserve.

Abstract

The present invention essentially consists of a coronary diagnostic assembly with a wire guide useful for both measuring pressure within a heart chamber for fractional flow reserve (FFR) and for performing cardiac pacing during pseudo FFR measurements, by means of a pressure sensor integrated within the wire guide.

Description

Technical Field

[0001] The present invention relates to a coronary diagnostic assembly for coronary angioplasty, where appropriate.

[0002] Coronary angioplasty is also called transluminal dilation, percutaneous transluminal coronary angioplasty (PTCA), or percutaneous coronary intervention (PCI).

[0003] More particularly, the present invention relates to improving the diagnosis of coronary artery dysfunction, especially in view of coronary angioplasty.

Background Art

[0004] Coronary angioplasty involves treating a coronary artery, for example in the case of coronary heart disease, by expanding a narrowed coronary artery using a probe with an inflatable balloon attached to its end.

[0005] The probe attached to a metal guide is introduced into the artery with an abnormality from a peripheral artery (radial or femoral). A metal guide wire is used to pass through the stenosis or occlusion. It serves as a guide to stably position the angioplasty probe.

[0006] In most cases, balloon angioplasty is assisted by the placement of a stent, which is a small metal prosthesis crimped onto the balloon.

[0007] Before performing coronary angioplasty, the operator makes a diagnosis.

[0008] Thus, in the context of investigating the hemodynamics of coronary stenosis, the use of the physiological function of the coronary artery is very often necessary and shows benefits regarding its diagnosis and prognosis. Its widely established use in countries around the world has improved the prognosis of patients.

[0009] More specifically, measuring coronary artery reserve or fractional flow reserve (FFR) is a straightforward and accepted method for non-invasively evaluating the functional effects of coronary artery lesions. The principle of FFR is based on measuring the pressure at both ends of the stenosis at maximum vasodilation (congestion), thereby enabling the quantification of the effects of specific coronary artery lesions. FFR measurement has become a standard criterion for hemodynamic significance in inducing vascular regeneration in intermediate coronary artery lesions.

[0010] The FFR can be easily measured during coronary angiography by using pressure guidance to calculate the ratio of the coronary artery pressure distal to the stenosis, i.e., the diseased section, to the aortic pressure under conditions of maximum myocardial congestion.

[0011] An FFR of 1.0 is widely accepted as normal. An FFR below 0.80 is generally associated with coronary ischemia and is considered to require vascular regeneration rather than conservative management.

[0012] FFR can confirm or rule out coronary artery stenosis (narrowing). 70% of stenosis may not require a stent, while 50% may require one.

[0013] The current standard method for measuring FFR involves inserting a pressure guide into the coronary artery while simultaneously administering a hypertensive agent, typically adenosine, via an intracoronary bolus.

[0014] To date, the administration of coronary artery function, particularly FFR, remains complex and, as described above, requires the administration of drugs to induce congestion, the most well-known of which is adenosine. Because it is carried by the intracoronary pathway, this drug is a vector of undesirable side effects, the most common of which are cardiac arrhythmias, such as bradycardia or cardiac arrest that is unpleasant or even dangerous, causing vagal discomfort or transient cardiac arrest in patients.

[0015] Therefore, the use of this technology may be limited by the fear of encountering this type of complication or side effect.

[0016] Therefore, in order to overcome the above shortcomings, there is a need to improve the diagnosis of coronary arteries, and more specifically, the diagnosis of coronary artery physiological function using FFR, with a particular focus on angiogenesis. [Overview of the Initiative] [Problems that the invention aims to solve]

[0017] The objective of this invention is to satisfy this need at least partially. [Means for solving the problem]

[0018] For this purpose, the subject of the present invention, according to a first alternative embodiment, is a coronary artery diagnostic assembly, An accessory catheter intended to be inserted into a peripheral artery or vein of the human body; A sleeve fitted to engage with the attached catheter, wherein the sleeve is made of a conductive material over at least a portion of its outer periphery, so that when the attached catheter is introduced into the peripheral artery or vein of the human body, the conductive periphery of the sleeve comes into contact with the subcutaneous tissue of the human body or with the wall of the artery or vein, and the sleeve is further connected to an electrical connection, the electrical connection itself is connected to an electrode of a cardiac stimulator outside the human body; A guidewire intended to be introduced into the insertion sheath of the attached catheter, wherein the guidewire comprises, at its distal end, a pressure sensor for measuring coronary reserve, and at its proximal end, a metal portion that further functions as a connection to the other electrode of the external cardiac stimulator and as a connection to a receiver for the pressure measured by the sensor. The coronary artery diagnostic assembly described above is equipped with the following:

[0019] According to the advantageous features, the electrode of the cardiac stimulator connected to the conductive sleeve engaged around the insertion sheath of the accessory catheter is the anode, while the electrode connected to the metal portion of the guidewire is the cathode.

[0020] According to an advantageous modified embodiment, the conductive sleeve is formed as a single piece made of a conductive material, such as carbon.

[0021] Preferably, the sleeve is formed by a sheath having a conductive coating, such as a carbon coating, on its outer periphery.

[0022] Advantageously, the sleeve is elastic so that it can engage with peripheral artery or venous catheter sheaths of various diameters, typically with an outer diameter of 1.6 to 20 mm.

[0023] The present invention also, according to a second alternative embodiment, is a coronary artery diagnostic assembly, An accessory catheter intended for insertion into a peripheral artery or vein of a human body, wherein the accessory catheter comprises at least one tubular insertion sheath and at least one conductive element, the distal portion of which is exposed at least in part to the outer periphery of the sheath so as to be in contact with the subcutaneous tissue of the human body or the wall of the peripheral artery or vein, and the proximal portion of which is accessible from the outside of the human body (C) comprises an electrical connection for serving as a connection to an electrode of a cardiac stimulator outside the human body; A guide wire intended to be introduced into the insertion sheath of the accessory catheter, where the guide wire has, at its distal portion, a pressure sensor for measuring coronary artery reserve capacity, and, at its proximal portion, a metal part that further functions as a connection to the other electrode of the external cardiac stimulator and as a connection to a receiver for the pressure measured by the sensor. Relates to the above coronary artery diagnostic assembly, which comprises.

[0024] The accessory catheter can be an introducer inserted into the patient's radial or femoral artery.

[0025] According to an advantageous feature, the electrode of the cardiac stimulator connected to the accessory catheter is an anode, while the electrode connected to the metal part of the guide wire is a cathode.

[0026] According to an embodiment of an advantageous modification, the conductive element of the accessory catheter is a wire or a metal band at least partially housed within the thickness of the sheath, the distal portion of which is exposed at the outer peripheral portion of the sheath.

[0027] Advantageously, the cross-sectional area of the wire or the metal band is 0.25 - 5 mm 2 is.

[0028] The pressure sensor can be a piezoelectric sensor or an optical fiber sensor connected to a central pressure measuring device by an electric wire or an optical fiber respectively. The inventors have overcome the preconception in this regard because the generation of the current for the desired cardiac stimulation is added to the electrical signal or the optical fiber signal for the pressure measurement. It has also been found that no interference is introduced, that is, the pressure measurement is not disturbed by the electrical signal of the cardiac stimulation

[0029] The assembly according to the present invention can additionally constitute a coronary angioplasty assembly involving the placement of a stent, where the guide wire is adapted to advance the stent.

[0030] The present invention also relates to a method for diagnosis and, where appropriate, cardiac intervention, the method is i / Engaging the sleeve around the attached catheter, wherein the sleeve is made of a conductive material over at least a portion of its outer circumference and further comprises electrical connections to electrodes of a cardiac stimulator outside the body. ii / To insert the attached catheter into a peripheral artery or vein of the human body such that the conductive peripheral portion of the sleeve is in contact with the subcutaneous tissue of the human body or with the wall of the artery or vein. iii / Introducing a guidewire into the insertion sheath of the attached catheter, wherein the guidewire is provided with a pressure sensor at its distal end and a metal portion at its proximal end that further functions as a connection to the other electrode of the external cardiac stimulator. As a measure of IV / coronary reserve, pressure is measured using the sensor, and simultaneously with the measurement of coronary reserve, direct cardiac stimulation is performed on the guidewire using an external cardiac stimulator. v / If applicable, once the stent is in place, cardiac stimulation is performed using the external cardiac stimulator, wherein the guidewire remains in place once step iv / is performed. This includes the following steps.

[0031] Finally, the present invention relates to a method for diagnosis and, where appropriate, cardiac intervention, the method is i' / Introducing an attached catheter into a peripheral artery or vein of a human body, wherein the attached catheter comprises at least one tubular insertion sheath and at least one conductive element, the distal portion of which is exposed over at least a portion of the outer periphery of the sheath to be in contact with the subcutaneous tissue of the human body or the wall of the peripheral artery or vein, and the proximal portion of which is accessible from the outside of the human body (C) comprises an electrical connection to serve as a connection to an electrode of a cardiac stimulator outside the human body. ii' / Introducing a guidewire into the insertion sheath of the attached catheter, wherein the guidewire is provided with a pressure sensor at its distal end and a metal portion at its proximal end that further functions as a connection to the other electrode of the external cardiac stimulator. iii' / As a measure of coronary artery reserve, pressure is measured using the sensor, and simultaneously with the measurement of coronary artery reserve, direct cardiac stimulation is performed on the guidewire using an external cardiac stimulator. iv' / If applicable, once the stent is in place, perform cardiac stimulation using the external cardiac stimulator, wherein the guidewire remains in place once step iii' / has been performed. This includes the following steps.

[0032] Thus, the present invention basically consists of a coronary artery diagnostic assembly, the guidewire of the assembly, through the pressure sensor built into the guidewire, serves both functions: to measure the pressure at both ends of the stenosis related to coronary flow rate (FFR), and to perform cardiac stimulation during this FFR measurement.

[0033] By introducing direct cardiac stimulation on a guidewire for FFR measurement, the assembly according to the present invention makes it possible to avoid undesirable side effects related to cardiac arrhythmias or conduction disorders, such as bradycardia or adverse cardiac arrest, as well as hyperemia that must be performed before FFR measurement.

[0034] Therefore, the present invention makes the FFR measurement procedure safer for both the practitioner and the patient, and enables this type of physiological investigation to be performed in any type of patient, even if theoretical contraindications arise for the use of adenosine necessary to perform hyperemia. One example of a contraindication is first-degree atrioventricular block.

[0035] In addition, the stimulation intensity required to induce cardiac arrest during FFR measurement is low. Typically, the supplied current intensity can be in the range of 4-25 mA, and the supplied voltage can be in the range of 1-15 volts, with cardiac arrest in mind.

[0036] This not only protects the patient from undesirable side effects (bradycardia, cardiac arrest), but also ensures that the patient feels little to no sensation related to the cardiac stimulation, given the large size of the intravascular electrode, typically the anode.

[0037] Therefore, one or more surgeons performing the surgery can easily connect one electrode, typically the anode of the cardiac stimulator, to the conductive sleeve engaged around the attached catheter, and then, as usual, connect the other electrode, typically the cathode, to the guidewire of the catheter / stent assembly or the balloon alone. This is particularly important for frail patients.

[0038] In summary, the coronary artery diagnostic assembly offers many advantages, including the following: The coronary FFR measurement procedure is made safer by eliminating all undesirable side effects associated with the intake of medications, such as adenosine, which is required to induce hyperemia prior to FFR measurement. The provision of "emergency" stimulation, i.e., the assurance of temporary stimulation in emergency situations. This is desirable because of the lower impedance of the vascular system encountered by the electrical stimulation current, since the sleeve around the attached venous catheter, or the latter, contains the metal part connected to the electrode and therefore comes into direct contact with the vascular system; Possibility of implementation on any existing peripheral venous or arterial catheter. This is because the conductive sleeve only needs to be engaged around the peripheral venous or arterial catheter before the catheter needs to be introduced into the peripheral vein or artery and an electrical connection needs to be made to the guidewire inserted into the catheter.

[0039] The only relative limitation of the sleeve is that, at the start of the intervention and during preparation, the sleeve must be engaged around the insertion sheath of the accompanying (peripheral artery) catheter.

[0040] However, this procedure is very simple and easy to perform and can be carried out by an assistant or nurse who does not require any special skills for this task.

[0041] Other advantages and features will become apparent when reading the detailed description given as a non-restrictive example, while referring to the attached drawings. [Brief explanation of the drawing]

[0042] [Figure 1] Figure 1 is a schematic diagram illustrating the use of a diagnostic assembly according to the present invention, which includes a peripheral arterial catheter and a stimulating sleeve according to the present invention, the catheter being directly introduced into the peripheral artery of the patient. [Figure 2] Figure 2 shows the placement of the guidewire of the assembly according to Figure 1 into the coronary artery being diagnosed. [Figure 3] Figure 3 is a perspective view of a conductive sleeve according to the present invention, intended to be engaged around a peripheral arterial catheter as shown in Figures 1 and 2. [Figure 4] Figure 4 is a partial longitudinal cross-sectional view showing the sleeve according to Figure 3 engaged around a peripheral arterial catheter. [Modes for carrying out the invention]

[0043] In the following description and throughout this application, the terms “distal” and “proximal” are used in reference to the body of a patient undergoing coronary artery diagnosis, in which coronary angioplasty is subsequently performed, as necessary. Thus, the distal end of the guidewire is the end that is furthest away within the patient during the diagnosis.

[0044] It should be noted that various elements are not necessarily shown to their actual scale.

[0045] Figures 1 and 2 show a coronary artery diagnostic assembly according to the present invention.

[0046] A peripheral arterial catheter 1, also called an attached catheter, is introduced into peripheral artery V.

[0047] Such an arterial catheter 1 can have a small diameter, typically 2 mm or less, and a short length. It meets the standards applicable to existing peripheral intravascular catheters. The catheter 1 may be equipped with a plugged internal cleaning device 10, commonly called a "flush," for cleaning the inside of the catheter 1 with a suitable cleaning fluid.

[0048] A conductive sleeve 2 is directly engaged around the peripheral artery catheter 1. The sleeve 2 is connected to an electrical connection 20, which in turn is connected via a power supply line 30 to an electrode, typically the anode of a cardiac stimulator 3 located outside the body C.

[0049] Guidewire 4 is introduced into the insertion sheath of the attached catheter 1.

[0050] As shown in Figure 2, the guidewire 4 has a pressure sensor 40 at its distal end for measuring the pressure at both ends of the stenosis in the coronary artery A, and a metal portion 41 at its proximal end that further functions as a connection to the other electrode, typically the cathode of the external cardiac stimulator. To ensure electrical connection, an alligator clip 5 is secured by clamping the metal portion 41 of the guidewire 4. This clip 5 is connected to the anode of the cardiac stimulator via a power supply line 31.

[0051] A sleeve 2 according to the present invention is shown in Figure 3, which is in the form of a tube, and at least a portion of its outer circumference is conductive.

[0052] This conductive portion is connected to an electrical connection 20, typically in the form of a clip, via a power supply line 21. The sleeve 2, clip 20, and power supply line 21 can be advantageously configured to form a kit that can be engaged around the catheter 1 and connected to the cardiac stimulator electrode 3.

[0053] The sleeve 2 may be cylindrical or frustoconical in shape. Its shape should match as closely as possible the outer shape of the insertion sheath of the peripheral artery catheter 1.

[0054] As can be seen in Figure 4, the thickness of this sleeve 2, which is typically about 1 millimeter or less, provides only a slight excess thickness to the sheath 11 of the arterial catheter 1, and therefore does not hinder the latter's progression when introduced into the peripheral artery V.

[0055] The sleeve 2 can be manufactured in the form of a single component that is entirely conductive, or in the form of a component coated with a conductive film. Carbon can be advantageously selected as the conductive material.

[0056] According to a favorable modification, the sleeve 2 can be designed to be elastic and thus able to conform to any size of existing peripheral arterial catheter.

[0057] In practice, a surgeon or interventional physician attempting to make a diagnosis in conjunction with cardiac stimulation begins by positioning the conductive sleeve 2 around the peripheral arterial catheter 1, as described below. The placement of the conductive sleeve is so simple and easy that it can be performed by an assistant or nurse without the need for any special skills.

[0058] The arrangement is achieved when the sleeve 2 is engaged and positioned around the insertion sheath of the arterial catheter 1 such that the sleeve 2 is in contact with either the subcutaneous region of the patient or the wall of a peripheral vein in the patient.

[0059] When this configuration is implemented, the electrical connection 20 can be directly connected to the anode of the external cardiac stimulator 3 via the connecting wire 30.

[0060] Next, a clip 5, typically an alligator clip, can be secured by clamping the metal portion 41 of the guidewire 4, which is inserted into the sheath 11 of the peripheral catheter 1 and positioned within the coronary artery where its pressure sensor 40 is to be diagnosed. The clip 5 is connected to the cathode of the external cardiac stimulator 3 via a connecting wire 31.

[0061] Therefore, the temporary cardiac stimulation required to achieve cardiac arrest during measurement of the pressure at both ends of the stenosis can be generated between the cathode electrically connected to the guidewire 4 and the anode electrically connected to the sleeve 2 according to the present invention around the peripheral venous catheter 1.

[0062] The method of coronary artery diagnosis and, if necessary, cardiac intervention performed by the assembly described above is now described.

[0063] This method is applied when the practitioner suspects stenosis within coronary artery A, for example, the stenosis shown as S in Figure 2, and wants to perform a coronary artery diagnosis, particularly measuring coronary artery reserve.

[0064] Process i / : The nurse or practitioner then proceeds to engage the conductive sleeve 2 around the terminal (attached) catheter 1.

[0065] Process ii / : Next, the practitioner introduces the catheter 1 into a peripheral artery or vein of the human body C such that the conductive peripheral portion of the sleeve 2 comes into contact with the subcutaneous tissue of the human body or with the wall of the artery or vein.

[0066] Step iii / : Next, the operator introduces the guidewire 4 into the insertion sheath 11 of the attached catheter 1 until it is ensured that the pressure sensor 40 is correctly positioned within the coronary artery A to be diagnosed.

[0067] Next, the practitioner proceeds to connect the electrical components to the external cardiac stimulator 3.

[0068] Therefore, the nurse or practitioner connects the sleeve 2 to the electrode, typically the anode of the external cardiac stimulator 3, on the one hand, and the metal portion 40 of the guidewire 4 to the other electrode of the stimulator 3 on the other hand.

[0069] Process iv / : After inducing congestion in the patient's body, the practitioner can measure the pressure at both ends of the stenosis using the sensor 40 as an indicator of the coronary artery reserve.

[0070] Simultaneously with the measurement of coronary artery reserve or FFR, direct cardiac stimulation is performed on the guidewire 4.

[0071] More precisely, the pressure or FFR is measured when the practitioner is confident that the adenosine administered to the patient has had an effect.

[0072] The cardiac stimulation can be triggered before the commencement of the pressure measurement, typically before or simultaneously with the practitioner ensuring that adenosine has taken effect. The practitioner may also decide to administer adenosine under cardiac stimulation using the guidewire according to the present invention.

[0073] Regarding the rate of cardiac stimulation, the practitioner can choose from the following two modes: A stimulation mode that can be described as “sentinel”: The external cardiac stimulator is set to a periodic threshold lower than the patient’s resting heart rate. As soon as the patient’s heart rate falls below the threshold, the stimulator is activated, and the cardiac stimulation is effective via the electrodes on the guidewire and the electrodes embedded in the sleeve or the accompanying catheter. For example, if the patient’s heart can beat 80 times per minute at rest, the external cardiac stimulator is triggered as soon as it drops to 60 beats per minute during FFR diagnosis. A continuous stimulation mode in which the external cardiac stimulator is triggered at a frequency higher than the patient's resting heart rate at all times during the FFR diagnosis and, if necessary, when adenosine is administered. For example, if the patient's resting heart rate is 60 beats per minute, the external cardiac stimulator operates continuously at a rate of 80 beats per minute.

[0074] Regardless of which mode is selected by the practitioner, this rate of stimulation can be easily performed, recognizing that the patient's heart rate is initially monitored and then continuously monitored throughout the intervention (coronary angioplasty may be performed after diagnosis), following the FFR procedure.

[0075] By performing cardiac stimulation in this manner simultaneously, the patient avoids all risks associated with bradycardia or adverse cardiac arrest that may be caused by congestion.

[0076] The coronary artery diagnostic assembly described above can also be used for coronary artery angioplasty.

[0077] In fact, at the end of step iv / , if the identified stenosis S requires the placement of a stent in the coronary artery A, a guidewire 4 incorporating an inflatable balloon along with the stent can be selected, and the stent can be placed in place without removing any of the components of the assembly.

[0078] Therefore, according to step v / , while the balloon and the stent are being placed, the operator performs another cardiac stimulation using the external cardiac stimulator, and the guidewire remains in place once step iv / is performed.

[0079] The present invention is not limited to the examples described herein, and in particular, the features of the described examples can be combined together in variations not described herein.

[0080] Other modifications and improvements can be provided without departing from the scope of the present invention.

[0081] In all the examples described, when a guidewire containing both a pressure sensor and a metal portion as an external cardiac stimulation electrode is used in a coronary artery diagnostic assembly, it can be used to take pressure at both ends of a stenosis in the cardiac chamber and to stimulate the cardiac chamber in the context of transcatheter aortic valve implantation (TAVI), in accordance with the teachings of French Patent Publication No. 3079404, European Patent No. 3522800, European Patent Publication No. 3280338(B1), French Patent Publication No. 3057153, and International Publication No. 2019 / 185880.

[0082] Guidewires for coronary artery diagnostic (FFR) assemblies can have a small diameter, typically equal to 0.035 mm (0.014 inches), while guidewires for assemblies that measure intracardiac pressure can have a larger diameter, typically around 0.9 mm (0.35 inches). In one embodiment, the present invention may be configured as follows. [Section 1] Coronary artery diagnostic assembly, An accessory catheter (1) intended to be introduced into a peripheral artery or vein of the human body; A sleeve (2) fitted to engage with the attached catheter, wherein the sleeve is made of a conductive material over at least a portion of its outer periphery, so that when the attached catheter is introduced into the peripheral artery or vein of the human body, the conductive periphery of the sleeve comes into contact with the subcutaneous tissue of the human body or with the wall of the artery or vein, and the sleeve is further connected to an electrical connection, the electrical connection itself is connected to an electrode of a cardiac stimulator (3) outside the human body. A guidewire (4) is intended to be introduced into the insertion sheath (11) of the attached catheter, wherein the guidewire has a pressure sensor (40) at its distal end for measuring coronary reserve, and a metal portion (41) at its proximal end that functions as a connection to the other electrode of the external cardiac stimulator and further functions as a connection to a receiver for the pressure measured by the sensor. The assembly comprising: [Section 2] The assembly according to item 1, wherein the electrode of the cardiac stimulator connected to the conductive sleeve engaged around the insertion sheath of the attached catheter is an anode, while the electrode connected to the metal portion of the guidewire is a cathode. [Section 3] The assembly according to claim 1 or 2, wherein the conductive sleeve is formed as a single piece made of a conductive material, such as carbon. [Section 4] The assembly according to claim 3, wherein the sleeve is formed by a sheath having a conductive coating, for example, a carbon coating, on its outer periphery. [Section 5] The assembly according to claim 3 or 4, wherein the sleeve is elastic so as to be able to engage with peripheral artery or venous catheter sheaths of various diameters, typically 1.6 to 20 mm in outer diameter. [Section 6] Coronary artery diagnostic assembly, An accessory catheter intended for insertion into a peripheral artery or vein of a human body, wherein the accessory catheter comprises at least one tubular insertion sheath and at least one conductive element, the distal portion of which is exposed at least in part to the outer periphery of the sheath so as to be in contact with the subcutaneous tissue of the human body or the wall of the peripheral artery or vein, and the proximal portion of which is accessible from the outside of the human body (C) comprises an electrical connection for serving as a connection to an electrode of a cardiac stimulator outside the human body; A guidewire intended to be introduced into the insertion sheath of the aforementioned accessory catheter, wherein the guidewire comprises, at its distal end, a pressure sensor for measuring coronary reserve, and at its proximal end, a metal portion that further functions as a connection to the other electrode of the external cardiac stimulator and as a connection to a receiver for the pressure measured by the sensor. The assembly comprising: [Section 7] The assembly according to item 6, wherein the electrode of the cardiac stimulator connected to the attached catheter is an anode, while the electrode connected to the metal portion of the guidewire is a cathode. [Section 8] The assembly according to item 6 or 7, wherein the conductive element of the attached catheter is a wire or metal band that is at least partially housed within the thickness of the sheath, and its distal portion is exposed at the outer peripheral portion of the sheath. [Section 9] The cross-sectional area of ​​the wire or metal band is 0.25 to 5 mm². 2 The assembly described in item 8. [Section 10] The assembly according to any one of items 1 to 9, wherein the pressure sensor is a piezoelectric sensor or an optical fiber sensor. [Section 11] The assembly may further constitute a coronary angioplasty assembly with stent placement, wherein the guidewire is adapted for advancing the stent, as described in any one of items 1 to 10.

Claims

1. Coronary artery diagnostic assembly, An accessory catheter intended to be inserted into a peripheral artery or vein of the human body (1); A sleeve (2) fitted to engage with the attached catheter, wherein the sleeve is made of a conductive material over at least a portion of its outer periphery, so that when the attached catheter is introduced into the peripheral artery or vein of the human body, the conductive periphery of the sleeve comes into contact with the subcutaneous tissue of the human body or with the wall of the artery or vein, and the sleeve is further connected to an electrical connection, the electrical connection itself is connected to an electrode of a cardiac stimulator (3) outside the human body. A guidewire (4) is intended to be introduced into the insertion sheath (11) of the attached catheter, wherein the guidewire has a pressure sensor (40) at its distal end for measuring coronary reserve, and a metal portion (41) at its proximal end that functions as a connection to the other electrode of the external cardiac stimulator and further functions as a connection to a receiver for the pressure measured by the sensor. The assembly comprising the above.

2. The assembly according to claim 1, wherein the electrode of the cardiac stimulator connected to the conductive sleeve engaged around the insertion sheath of the attached catheter is an anode, while the electrode connected to the metal portion of the guide wire is a cathode.

3. The assembly according to claim 1 or 2, wherein the conductive sleeve is formed as a single piece made of a conductive material.

4. The assembly according to claim 3, wherein the sleeve is formed by a sheath having a conductive coating on its outer peripheral portion.

5. The assembly according to claim 3 or 4, wherein the sleeve is elastic so as to be able to engage with peripheral artery or venous catheter sheaths of various diameters, typically 1.6 to 20 mm in outer diameter.

6. Coronary artery diagnostic assembly, An accessory catheter intended for insertion into a peripheral artery or vein of the human body, wherein the accessory catheter comprises at least one tubular insertion sheath and at least one conductive element, the distal portion of which is exposed at least a portion of the outer periphery of the sheath to be in contact with the subcutaneous tissue of the human body or the wall of the peripheral artery or vein, and the proximal portion of which is accessible from the outside of the human body (C) comprises an electrical connection for serving as a connection to an electrode of a cardiac stimulator outside the human body; A guidewire intended to be introduced into the insertion sheath of the aforementioned accessory catheter, wherein the guidewire comprises, at its distal end, a pressure sensor for measuring coronary reserve, and at its proximal end, a metal portion that further functions as a connection to the other electrode of the external cardiac stimulator and as a connection to a receiver for the pressure measured by the sensor. The assembly comprising the above.

7. The assembly according to claim 6, wherein the electrode of the cardiac stimulator connected to the attached catheter is an anode, while the electrode connected to the metal portion of the guidewire is a cathode.

8. The assembly according to claim 6 or 7, wherein the conductive element of the attached catheter is a wire or metal band that is at least partially housed within the thickness of the sheath, and its distal portion is exposed at the outer peripheral portion of the sheath.

9. The cross-sectional area of ​​the wire or metal band is 0.25 to 5 mm². ２ The assembly according to claim 8.

10. The assembly according to any one of claims 1 to 9, wherein the pressure sensor is a piezoelectric sensor or an optical fiber sensor.

11. The assembly may further constitute a coronary angioplasty assembly with stent placement, wherein the guidewire is adapted for advancing the stent, according to any one of claims 1 to 10.

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