FR2879435A1 - Metallic strands maintaining device for use in e.g. vena cava filter and pace wire, has flat part incorporated on oblate tubular metallic strand, and around which multiple lumen catheter material is molded so as to match with strand form - Google Patents

Abstract

The device has a flat part incorporated on an oblate tubular metallic strand of an intervention system such as vena cava filter or pace wire. Material of a multiple lumen catheter used for positioning the strand, is molded around the flat part of the strand, in order to be matched with the oblate tubular form of the strand.

Description

The present invention relates to a device for holding mounted wires

  in interventional systems used in medicine, particularly in cellar filtration applications.

  Many medical devices, including cell filters, use round metal wires formed and held in designated geometric positions to perform their function. Some examples of medical devices of this type are vena cava filters, jugular artery filters, stent stents, endovascular lumen reopening devices, cardiac pacing probes and many other devices applied in radiology. in cardiology, other medical disciplines or surgery.

  All these devices require that the used metal wires maintain a geometric relationship with each other and each relative to the positioning mechanism, often a catheter. In the case of the cellar filter, the formed wires constitute a system capable of capturing blood clots to prevent these clots from progressing to the heart and the pulmonary artery where they could block the circulation of the blood and cause complications or even death of the patient. Indeed, the distance between each wire should not be too large at the risk of letting dangerous clots pass; in the same way, if the wires are too close, they could interfere with normal blood circulation. In a similar manner, a device for cleaning the endovascular lumen, must have a suitable shape and must have a correct geometric relation to the positioning catheter.

  The shapes and geometric relationships between the wires and catheters constituting implantable probes, stents and jugular artery filters must also form and maintain a given geometric configuration.

  Catheters and other flexible systems that use plastics and other suitable materials are part of many devices because they facilitate positioning. An example of the usefulness of a catheter for positioning in the human body would be the cave filter: the catheter can be easily pushed to the desired level in the vena cava and once the position is reached, the filter itself can be deployed . The catheter is often associated with metal wires to benefit from the specific characteristics of these wires and in particular their spring effect and robustness.

  A difficulty encountered in the realization of such systems combining catheter and son is the maintenance of the relationship between the wire and the catheter. The thread, by its round form, tends to turn on itself. Because of this rotation, the designated geometric shape is lost and the effectiveness of the device is compromised. Let's take again the example of the cellar filter. A used construction has a plurality of wires mounted in the periphery of a multi-lumen catheter issuing from the same catheter to form the filter to be subsequently joined at the distal end of the device. If the wires turn on their own, the designated shape of the filter is compromised. This suboptimal form allows clots to pass and / or disturb the blood circulation. This is why a device which blocks the rotation of the wires, has a considerable interest in the realization of the cellar filter and other devices where round wire son associated with catheters are used to form active devices.

  The present invention proposes to provide a simple and inexpensive solution to the problem mentioned above.

  To this end, the invention relates to a device which prevents the rotation of metallic round wires mounted in catheters included in interventional systems of medicine and surgery, a device including a specific form given to a portion of the wire and a work performed on the material constituting the catheter.

  The device is characterized according to the invention in that a flat 10 is incorporated on a portion of the wire and that the material which carries the wire is molded around the flat.

  The flattened part of the wire is in contact with the surrounding material and therefore can not turn on itself. The part of the wire with the flat does not turn and prevents the whole wire to turn on itself. In this way, any rotation of the wire is prevented.

  According to an advantageous aspect of the invention, although not limiting, the flatbed and the molding which surround it will be used to maintain the precise geometry of a cellar filter. The medical technique in which this thread is used is the subject of numerous studies published by the team of Professor Claude THERY. This filter, consisting of a plurality of strands disposed in a spiral, deploys in the vein substantially in the form of a rugby ball without getting stuck in the venous wall. Its maintenance is ensured by the elastic force of the strands, which causes no trauma of the vein. In addition, this design ensures easy removal of the filter, if necessary without surgery.

  The invention will now be described with reference to the accompanying drawings in which Figure 1 schematically shows the flat and Figure 2 the consolidation of the flat in the catheter material.

  Figure 3 shows a subset of cellar filter with the son deployed as found during the application of the filter.

  Moreover, the invention is not limited to the vena cava filter, it can be applied to any device in which round metal wires incorporated in a moldable material are used.

  Figure 4 shows a spiral conductor inside the insulator of a pacemaker probe with flat on the leads constituting the conductor of the probe; the insulation is molded to fit the flattened shape of the wire.

  In the case of the flattened wire of the pacemaker probe lead and the molding of the corresponding insulator, the contact between the conductor and the insulator is reinforced to facilitate the removal of the probe by avoiding that the conductor consisting of turns and the Insulation does not get longer under a pulling force.

  Indeed, it is often difficult or impossible to surgically remove cardiac stimulation probes implanted in the heart because of the longitudinal excessively long elasticity of the probes associated with the anchoring of the distal end in the endocavitary tissues.

Claims (2)

  1. Device for holding metal son in medical systems, said device being characterized in that in addition a flat is formed on each wire (1).   2. Device according to claim 1 characterized in that the material of the catheter is molded to fit the flattened form of the wire (2).