Collapsible catheter

Abstract

An intravascular system includes an introducer sheath (104) having a fixed diameter lumen, a first medical device (102), and a catheter (106) having a proximal end and a distal end coupled to the first medical device. When the catheter is positioned within the introducer sheath, an annular gap is formed between an outer circumference of the catheter and an inner circumference of the lumen. The catheter is configured to adopt different dimensional configurations (y, z) such that the size of the catheter and the size of the annular gap are variable. The variability of the size of the catheter allows another medical device to pass through the annular gap within the lumen. The catheter can be passively changed in configuration as the second medical device passes adjacent thereto, or actively changed in configuration by an active mechanism under the control of a physician.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Application No. 62 / 908,199, filed September 30, 2019, the contents of which are incorporated herein by reference. Background Technology

[0003] If a physician plans to use mechanical circulatory support, physicians performing high-risk percutaneous coronary intervention (HRPCI) currently use two separate entry points for accessing the arterial system. The first entry point is for inserting the PCI device into the right femoral, radial, or brachial artery, and the second point is for inserting the blood pump into the left femoral artery. Using two entry points presents several disadvantages for physicians, including the additional time spent performing two insertions, a greater chance of complications during the procedure, the need for more introducers and closure devices, and a higher likelihood of not being able to treat certain patients, such as those with vascular problems. Vascular problems, such as peripheral artery disease, can be present in both femoral arteries, and in some cases, the radial or brachial artery may be blocked from entry. For example, some patients may also require a third entry point if chronic total occlusion (CTO) must also be treated. The dual-entry problem also applies to venous conditions, where, for example, the blood pump is often used with pulmonary artery catheterization (PAC), and to large-port procedures, where, for example, transcatheter aortic valve replacement (TAVR) or endovascular aneurysm repair (EVAR) requires a contralateral contrast-injection catheter.

[0004] Current techniques for performing single-entry point interventions involve placing a first device through a dissecting sheath and then advancing a second device alongside the first device within the dissecting sheath. Limitations of this technique include the physician's inability to maintain the position of the first device during manipulation of the second device, poor hemostasis from the introducer valve, which is designed solely for insertion of one device, and a higher likelihood of dissecting sheath hub rupture. In some cases, the introducer sheath valve is punctured with a needle adjacent to the blood pump catheter before insertion of the second device; puncturing the sheath valve instead of through its center reduces the valve's hemostatic properties, leading to a higher likelihood of intraoperative complications such as significant blood loss. In one example, a 14French (Fr) dissecting sheath is inserted into the vascular system for the introduction of a 9Fr device manufactured by Abiomed. Blood pump and catheter. Once the pump is started and running, the physician uses a needle to puncture a hole in the hemostatic valve of the introducer sheath, delivers a guidewire through the valve, and then delivers a long 7Fr introducer sheath with a hub for PCI. This exemplary method has limitations because the 14Fr stripping sheath has an inner diameter and a break line, so the physician must carefully consider the wall thickness and remaining available space when inserting the secondary 7Fr sheath to avoid breaking the stripping sheath.

[0005] It would be desirable to have a device that allows for single access method to insert more than one device into the vasculature. A single access method has several advantages by dedicating a large bore introducer sheath to a plurality of medical devices. A single access system minimizes access to a sterile field and thus reduces the likelihood of contamination, surgical site infection, and other surgical related complications. A single access system also advantageously reduces the number of access sites to manage and allows for a single well-defined procedure. One approach to a solution for the insertion of two devices using a single standard introducer sheath of limited diameter would involve reducing the overall size of the devices to at least match the diameter of the sheath. SUMMARY

[0006] The systems and methods herein enable the insertion of multiple medical devices into a patient's vasculature through a single access point of an introducer sheath by coupling the medical devices to a collapsible catheter. The collapsible catheter allows other medical devices to pass within the introducer sheath and adjacent to the catheter when the collapsible catheter is positioned within a fixed diameter introducer sheath.

[0007] In one example aspect, an intravascular system includes an introducer sheath having a lumen of fixed inner diameter; a first medical device; and a catheter having a proximal end, a distal end coupled to the first medical device, and an outer circumference configured to assume a first dimension or a second dimension when positioned within the lumen of fixed inner diameter. The catheter can be positioned within the lumen of the sheath and leave an annular gap between the outer circumference of the catheter and the inner circumference of the lumen of the sheath such that the size of the annular gap is variable by virtue of the outer circumference of the catheter having the first dimension and the second dimension. In certain dimensional configurations of the catheter, the annular gap is sized to allow a second medical device to pass therethrough. The first medical device can be a blood pump and the second medical device can be a PCI device, another catheter, or another introducer sheath. The catheter can be composed of a flexible layer and a rigid layer removably attached to the catheter such that the size of the catheter is permitted to change after removal of the rigid layer. The rigid layer can enable a physician or operator to insert and position the catheter within the vasculature. After removal of the rigid layer, the flexible layer can deform to accommodate a second medical device to fit adjacently within the annular gap. The catheter can instead be composed of a catheter frame that can be actively triggered by a physician to collapse or expand. The catheter frame can be composed of a plurality of strands that can form a woven mesh and a polymeric coating. At least one advantage of this example aspect is that the catheter is compatible with commonly used introducer sheaths and medical devices that can be introduced within the sheath next to the catheter. At least one other advantage of this example aspect is that the catheter can be manipulated at the physician's discretion during positioning of a medical device coupled to the catheter and during the introduction of additional medical devices next to the catheter.

[0008] In another aspect, a method for introducing medical devices into a patient's vasculature through an introducer sheath uses a catheter to accommodate multiple devices within a fixed size sheath. An introducer sheath having a fixed inner diameter lumen is percutaneously inserted into a patient's vasculature to provide an access point for intravascular medical devices. A first medical device coupled to a catheter is introduced through the lumen. The first medical device can be a blood pump. While the catheter is positioned within the fixed inner diameter lumen, an outer circumference of the catheter is configured to adjustably assume a first dimension or a second dimension. The catheter can be positioned within the lumen of the sheath and leave an annular gap between the outer circumference of the catheter and an inner circumference of the lumen of the sheath. In certain dimensional configurations of the catheter, the annular gap is sized to allow a second medical device to pass therethrough. The method can further include introducing the second medical device through the annular gap. The second medical device can be a PCI device, another catheter, or another introducer sheath. In some embodiments, as the second device is inserted adjacent, the outer circumference of the catheter is passively changed in dimension. In other embodiments, the catheter must be actively triggered by a physician to deform before the second medical device is inserted adjacent. In further embodiments, the method includes introducing the introducer sheath into the vasculature, introducing the first medical device coupled to the catheter that can be triggered to change in dimension, changing the catheter to increase the annular gap, and introducing the second medical device through the annular gap. In some embodiments, the second medical device is introduced into the lumen before the first medical device is coupled to the catheter, and as the catheter is inserted adjacent the second medical device, the outer circumference of the catheter changes in dimension. At least one advantage of this aspect is that the physician is provided with the ability to manipulate the catheter as desired before, during, or after the catheter is introduced through the introducer sheath. At least one other advantage of this aspect is that multiple medical problems can be addressed through one access point by using multiple medical devices. This aspect can also allow the physician to manipulate the catheter to accommodate another medical device through the same access point as needed, for example, when another medical device is needed to address a complication that arises during a procedure on the patient. BRIEF DESCRIPTION OF DRAWINGS

[0009] The foregoing and other objects and advantages will become apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters designate like parts and in which:

[0010] Figure 1A A catheter in a first configuration coupled to a medical device and positioned within a sheath is shown in accordance with an illustrative embodiment;

[0011] Figure 1B A catheter in a second configuration coupled to a medical device and positioned within a sheath with another medical device positioned adjacent within the sheath is shown in accordance with an illustrative embodiment.

[0012] Figure 2 A catheter having a rigid inner layer and a flexible outer layer is shown in accordance with an illustrative embodiment;

[0013] Figure 3 A catheter having a flexible inner layer and a rigid inner layer is shown in accordance with an illustrative embodiment;

[0014] Figure 4 A catheter frame including a coated braid for collapsing and expanding a catheter is shown in accordance with an illustrative embodiment;

[0015] Figure 5 A flowchart of introducing a collapsible catheter is shown in accordance with an illustrative embodiment;

[0016] Figure 6 A flowchart for introducing a blood pump coupled to a collapsible catheter and a PCI device through one introducer sheath is shown in accordance with an illustrative embodiment;

[0017] Figure 7 A flowchart for introducing a medical device coupled to a collapsible catheter next to a previously introduced medical device is shown in accordance with an illustrative embodiment; and

[0018] Figure 8 A flowchart for introducing a medical device coupled to a collapsible catheter, changing the configuration of the catheter, and introducing another medical device next to the catheter is shown in accordance with an illustrative embodiment. DETAILED DESCRIPTION

[0019] To provide a complete understanding of the systems, methods, and apparatuses described herein, certain illustrative embodiments will be described. Although the embodiments and features described herein are specifically described for use in conjunction with intravascular catheterization, it will be understood that all of the components and other features outlined below can be combined with each other in any suitable manner and can be adapted and applied to other types of procedures requiring a catheter.

[0020] The term proximal should be understood to refer to a position on the catheter that is relatively closer to an operator during use of the catheter, while the term distal should be understood to refer to a position on the catheter that is relatively further from the operator during use of the catheter. The term “upstream” should be understood to refer to a position on the catheter that is relatively more upstream in the blood flow within a blood vessel when the catheter is in place in the patient’s blood vessel. The term “downstream” should be understood to refer to a position on the catheter that is relatively more downstream in the blood flow within a blood vessel when the catheter is in place in the patient’s blood vessel. The term physician should be understood to refer to any physician, doctor, or operator using the described systems or methods.

[0021] Figure 1A and Figure 1BAn endovascular system 100 configured for percutaneous insertion of two medical devices into a patient's vascular system via an introducer sheath is shown. A variable-sized catheter is coupled to a first medical device such that a second medical device is fitted alongside the catheter within the introducer sheath. A cross-section of the system shows the variation in catheter size with and without the second medical device introduced.

[0022] Figure 1A An endovascular system 100 is shown, comprising a first medical device 102, an introductory sheath 104, and a catheter 106. The first medical device 102 is coupled to the distal end of the catheter 106. As shown, the catheter 106 extends through the lumen 108 of the introductory sheath 104. The lumen 108 has a fixed inner diameter. The introductory sheath 104 has a cross-sectional dimension X. In this arrangement, the catheter 106 is in a first configuration and has a first dimension Y. When the catheter 106 is positioned within the lumen 108 of the introductory sheath 104, an annular gap exists between the outer circumference 110 of the catheter 106 and the inner circumference 112 of the lumen 108. The catheter 106 has variable dimensions, and therefore the annular gap also has variable dimensions.

[0023] The introducer sheath 104 can be configured for percutaneous insertion into the patient's vascular system, and the first medical device 102 can be configured to be positioned in the vascular system after proximal insertion through the introducer sheath 104. In one example, the first medical device 102 is a blood pump configured to be positioned within the patient's heart via the vascular system. The blood pump may include a motor, rotor, pump housing, cannula, distal opening, and atraumatic extension. In some embodiments, the first dimension Y is between 8 Fr and 11 Fr. In some embodiments, the first dimension Y is between 9 Fr and 10 Fr. In some embodiments, the first dimension Y is 9 Fr. Figure 1A In the system, the annular gap can have a dimension A1, where in some embodiments, A1 = XY. For example, dimension Y can have a value greater than zero and less than or equal to the value of dimension X, and dimension A1 can have a value in the range from zero to the value of dimension X. At least one advantage of the variable-size catheter 106 is that the annular gap within the lumen 108 is also variable-size, and the size of the annular gap can be adjusted to a desired size, for example, by changing the configuration of the catheter 106, such that the dimension of the catheter 106 in the new configuration is not equal to Y. In one example, the desired size of the annular gap can be adapted to the size of a second medical device.

[0024] Figure 1BAn intravascular system 100 is shown having a first medical device 102, an introducer sheath 104, a catheter 106, and a second medical device 114. The first medical device 102 is coupled to a distal end of the catheter 106. The first medical device 102 is positioned in the vasculature after being inserted proximally through the introducer sheath 104. The catheter 106 is positioned within a lumen 108 of the introducer sheath 104. The second medical device 114 is positioned alongside the catheter 106 and within the lumen 108 such that it resides within an annular gap formed between an outer circumference 110 of the catheter 106 and an inner circumference 112 of the lumen 108. When the second medical device 114 is positioned within the annular gap concurrently, the catheter 106 is in a second configuration and has a second dimension Z.

[0025] For example, the second medical device 114 can be a PCI device. In some embodiments, the second medical device 114 is a secondary introducer sheath or a secondary catheter. In some embodiments, the annular gap in the second configuration is sized to allow the second medical device 114 to pass therethrough. In further embodiments, the second medical device 114 cannot fit within the annular gap when the catheter 106 is in the first configuration, so the catheter 106 is in the second configuration to allow the second medical device 114 to pass. In some embodiments, the annular gap in the second configuration is larger than the annular gap in the first configuration. In some embodiments, the catheter 106 is in the second configuration when the second medical device 114 is passing through the annular gap, and the catheter 106 is in the first configuration when the second medical device 114 is not in the annular gap.

[0026] In some embodiments, the second dimension Z is between 7 Fr and 9 Fr. In some embodiments, the second dimension Z is 7 Fr. In some embodiments, the second dimension Z is 9 Fr. Figure 1B In systems of the type shown in FIG. 1, the annular gap can have a dimension A2, where A2 = X - Z, and can have a value different from the value of the dimension A1 of the annular gap in systems of the type shown in FIG. 1. Figure 1A For example, the second dimension Z can have a value greater than zero and less than or equal to the value of X, and the dimension A2 can have a value in a range from zero to the value of X.

[0027] The catheter 106 can be changed from the first configuration to the second configuration, or vice versa, by active or passive mechanisms including, for example, reinforced strands, tensioned wires, woven mesh, sleeves of variable stiffness, rheological materials, inflatable elements, or pneumatic elements. In embodiments of the variable size catheter having active mechanisms for dimensional change, the catheter 106 is triggered by a physician or operator to change configuration. In embodiments of the variable size catheter having passive mechanisms, the introduction of the second medical device 114 adjacent to the catheter 106 within the lumen 108 of the introducer sheath 104 forces the catheter 106 to change to the second configuration; the second medical device can exert a normal force on the outer wall of the catheter 106 and deform the shape or dimensional configuration of the catheter 106.

[0028] In certain embodiments, only the portion of the catheter 106 within the lumen 108 changes from the first configuration to the second configuration, while the remaining portion of the catheter 106 not within the lumen 108 does not change configuration. For example, the first medical device 102 and the catheter 106 coupled thereto are introduced through the introducer sheath 104 such that the portion of the catheter 106 defined by a longitudinal length shorter than the total longitudinal length of the catheter 106 is within the lumen 108 of the introducer sheath 104, and the remaining length of the catheter 106 is positioned outside of the introducer sheath 104; as the second medical device 114 is introduced alongside the catheter 106, only the portion of the catheter 106 within the lumen 108 undergoes a change from the first configuration to the second configuration.

[0029] In some embodiments, the first dimension and the second dimension are measures of a length of a cross-section of the catheter. In some embodiments, the cross-section of the catheter is circular, and the first dimension and the second dimension are diameters of the circular cross-section. In some embodiments, the cross-section of the catheter is not circular, and the first dimension and the second dimension are widths of the cross-section in one direction.

[0030] In Figure 1A In this arrangement, the catheter 106 is positioned within the lumen 108 of the introducer sheath 104. An annular gap is formed between the outer circumference 110 of the catheter 106 and the inner circumference 112 of the introducer sheath 104. In this arrangement, the catheter 106 is in the first configuration and has the first dimension Y, and the introducer sheath has the cross-sectional dimension X.

[0031] In some embodiments, the first dimension Y is a measure of a size of a cross-section of the catheter 106. In further embodiments, the cross-section is circular, and the first dimension Y is a diameter of the circular cross-section; or the cross-section is not circular, and the first dimension Y is a width of the cross-section in one direction. The cross-section of the catheter 106 can be elliptical, circular, or some amorphous form. Alternatively, the first dimension Y can be any selected dimension related to the size of the catheter 106.

[0032] InFigure 1B In this arrangement, catheter 106 is positioned within the lumen 108 of introducer sheath 104. Introducer sheath 104 has a cross-sectional dimension X. An annular gap is formed between the outer circumference 110 of catheter 106 and the inner circumference 112 of introducer sheath 104. A second medical device 114 is positioned within the annular gap and adjacent to catheter 106. In this arrangement, catheter 106 is in a second configuration and has a second dimension Z, which is at least less than X, so that the second medical device 114 is positioned within the annular gap.

[0033] The sheath cross-sectional dimension X sets a limit on the overall size of the catheter 106 and the second medical device 114 that can fit within a single intubation sheath 104. For example, the second medical device 114 may have a cross-sectional dimension S, and dimension X may constrain dimensions Z and S such that Z + S ≤ X. In another example, the sum of the first dimension Y and the second device dimension S is greater than the sheath dimension X, indicating that the catheter 106 needs to be adjusted to the second dimension Z so that both the catheter 106 and the second medical device 114 fit within a lumen 108 of a fixed inner diameter. In some embodiments, the second dimension Z is a measurement of the length of the cross-section of the catheter 106. In a further embodiment, the cross-section is circular, and the second dimension Z is the diameter of the circular cross-section; or the cross-section is not circular, and the second dimension Z is the width of the cross-section in one direction. The cross-section of the catheter 106 may be elliptical, circular, or some amorphous form. Alternatively, the second dimension Z may be any selected dimension related to the size of the catheter 106.

[0034] In some embodiments, the annular gap when catheter 106 is in the second configuration is sized to allow a third medical device to mate adjacent to catheter 106 and a second medical device 114 within lumen 108. In a further embodiment, the annular gap when catheter 106 is in the second configuration is sized to allow multiple devices to mate adjacent to catheter 106 within lumen 108.

[0035] exist Figure 1A and Figure 1B At least one advantage of the system shown and described is that the use of the variable-size catheter 106 allows a second medical device 114 to be positioned adjacent to the catheter 106 within a fixed-diameter lumen 108. By using only one introducer sheath 104 for inserting both medical devices 102 and 114, the system addresses the need for single-entry introduction of multiple endovascular devices. This solution advantageously minimizes the number of closure devices required to manage endovascular entry-related complications and access sites.

[0036] Figure 2 The diagram shows an axial cross-section of a catheter 206 comprising a rigid inner layer 216 and a flexible outer layer 218. The catheter 206 is a variable-size catheter (such as those from...).Figure 1A and Figure 1B catheter 106) of FIGS. 1-5. The layers 216 and 218 extend from a proximal end to a distal end of the catheter 206. The rigid inner layer 216 is removably attached to the catheter 206 or the flexible outer layer 218. The catheter 206 can be the catheter 106 of FIGS. 1-5. Figure 1A and Figure 1B catheter 106 of FIGS. 1-5. The layers 216 and 218 extend from a proximal end to a distal end of the catheter 206. The rigid inner layer 216 is removably attached to the catheter 206 or the flexible outer layer 218. The catheter 206 can be the catheter 106 of FIGS. 1-5. Figure 1A and Figure 1B catheter 106 of FIGS. 1-5. The layers 216 and 218 extend from a proximal end to a distal end of the catheter 206. The rigid inner layer 216 is removably attached to the catheter 206 or the flexible outer layer 218. The catheter 206 can be the catheter 106 of FIGS. 1-5. Figure 1A and Figure 1B catheter 106 of FIGS. 1-5. The layers 216 and 218 extend from a proximal end to a distal end of the catheter 206. The rigid inner layer 216 is removably attached to the catheter 206 or the flexible outer layer 218. The catheter 206 can be the catheter 106 of FIGS. 1-5. Figure 1A and Figure 1B catheter 106 of FIGS. 1-5. The layers 216 and 218 extend from a proximal end to a distal end of the catheter 206. The rigid inner layer 216 is removably attached to the catheter 206 or the flexible outer layer 218. The catheter 206 can be the catheter 106 of FIGS. 1-5.

[0037] The at least one of the rigid inner layer 216 and the flexible outer layer 218 can be composed of a polymer. The polymer is selected to have a stiffness suitable for rigidity or flexibility. In some embodiments, the polymer includes at least one of ethylene vinyl acetate, polyethylene, polyolefin elastomer, maleic anhydride grafted polymer, styrene butadiene styrene, polypropylene-based elastomer, styrene butadiene copolymer, thermoplastic polyester elastomer, thermoplastic polyurethane elastomer, thermoplastic vulcanizate, polyamide, polytetrafluoroethylene, aromatic polyester, polyvinyl chloride, polymethyl methacrylate, acrylonitrile butadiene styrene, styrene acrylonitrile, polystyrene, polyethylene terephthalate copolymer, polycarbonate, polyphenylene ether, polyphenylene ether, acetate, butyrate, propionate, polysulfone, polyether sulfone, polyaryl sulfone, polybutylene terephthalate, polyester terephthalate, acetal, fluorinated ethylene propylene, perfluoroalkoxy polymer, ethylene chlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene perfluoromethyl vinyl ether, tetrafluoroethylene, hexafluoropropylene, liquid crystal polymer, and polyether ether ketone.

[0038] In some implementations, the rigid inner layer 216 includes at least one peel slit that allows for removal of the rigid inner layer 216 in a proximal direction. In other implementations, the rigid inner layer 216 is removably attached to the catheter 206 by a locking mechanism, and can be removed by twisting a proximal end of the rigid inner layer 216 to unlock the mechanism and slide the rigid inner layer 216 proximally out of the catheter 206. The catheter 206 can be configured to be positioned within an introducer sheath, forming an annular gap between the catheter 206 and the introducer sheath. In some implementations, the rigid inner layer 216 is removed from the catheter 206, and a second medical device, such as the first medical device 102 of FIGS. 1-5, is introduced through the annular gap. Figure 1A andFigure 1B the second medical device 114 in the second medical device 114) proximate to the catheter 206 introduces a fixed size lumen (such as Figure 1A and Figure 1B the lumen 108 in the introducer sheath 104 in the second medical device 114) and the second medical device exerts a normal force on the flexible outer layer 218, where the flexible outer layer is constrained to the second configuration by the normal force such that both the catheter and the medical device fit within the fixed size lumen. While the rigid inner layer 216 is attached to the catheter 206, the catheter 206 does not change from the original configuration, which is optimal for insertion, mobilization, and positioning of the catheter 206 and the distally coupled medical device. At least one advantage of the catheter 206 is that the difference in stiffness of the layers 216 and 218 can allow a physician to manipulate the size of the catheter 206 by removing the rigid inner layer 216 during an operation such that the remaining flexible outer layer 218 can deform to change the size of the annular gap within the introducer sheath to fit the second medical device through the annular gap.

[0039] Figure 3 An axial cross-section of a catheter 306 is shown that includes a flexible inner layer 320 and a rigid outer layer 322, the catheter 306 being an example of a variable size catheter such as the catheter 106 from Figure 1A and Figure 1B The layers 320 and 322 extend from a proximal end to a distal end of the catheter 306. The rigid outer layer 322 is removably attached to the catheter 306 or the flexible inner layer 320. The catheter 306 can be the catheter 106 in Figure 1A and Figure 1B When the catheter 306 is positioned in, for example, the introducer sheath 104 from Figure 1A and Figure 1B The rigid outer layer 322 can be removed proximally. The removal of the rigid outer layer 322 allows the catheter 306 to change from a first configuration to a second configuration, for example, the first and second configurations described with respect to the catheter 106 from Figure 1A and Figure 1B The rigid outer layer 322 is configured to allow a physician to mobilize and manipulate the catheter 306 during introduction of a medical device (e.g., the first medical device 102 from Figure 1A and Figure 1B The catheter 306.

[0040] At least one of the rigid outer layer 322 and the flexible inner layer 320 can be composed of a polymer. The polymer can be selected to have a stiffness appropriate for rigidity or flexibility. In some embodiments, the rigid outer layer 322 includes at least one peel slit that allows the rigid outer layer 322 to be removed in a proximal direction. In other embodiments, the rigid outer layer 322 is removably attached to the catheter 306 by a locking mechanism, and can be removed by twisting a proximal end of the rigid outer layer 322 to unlock the mechanism and slide the rigid outer layer 322 proximally out of the catheter 306. The catheter 306 can be configured to be positioned within an introducer sheath, forming an annular gap between the catheter 306 and the introducer sheath. In some embodiments, the rigid outer layer 322 is removed from the catheter 306 and a medical device (such as a second medical device 114 in Figure 1A and Figure 1B The second medical device 114 is introduced proximate to the catheter 306 within a fixed-size lumen, such as the lumen 108 in the introducer sheath 104 in Figure 1A and Figure 1B and the medical device exerts a normal force on the flexible inner layer 320, where the flexible inner layer is constrained to a second configuration by the normal force, such that both the catheter and the medical device fit within the fixed-size lumen. While the rigid outer layer 322 is attached to the catheter 306, the catheter 306 does not change from the original configuration, which is optimal for insertion, mobilization, and positioning of the catheter 306 and the distally coupled medical device. At least one advantage of the catheter 306 is that the difference in stiffness of the layers 320 and 322 can allow a physician to manipulate the size of the catheter 306 by removing the rigid outer layer 322 during an operation, such that the remaining flexible inner layer 320 can be deformed to change the size of the annular gap within the introducer sheath in order to fit a second medical device through the annular gap.

[0041] Figure 4 A segment of a catheter 406 is shown having a constricted portion and an expanded portion, the catheter 406 being an example of a variable-size catheter, such as from Figure 1A and Figure 1BThe catheter 106. The contraction and expansion of the catheter 406 are achieved by a catheter frame 424 and a polymer layer 430. The catheter frame 424 includes a first plurality of strands 426 and a second plurality of strands 428, both extending longitudinally from the proximal end to the distal end of the catheter 406. The polymer layer 430 forms a coating around the outer surface of the catheter frame 424. The catheter frame 424 is configured to reversibly deform from a first configuration to a second configuration. Deformation from the first configuration to the second configuration is the contraction of the catheter frame 424, and the reverse deformation from the second configuration to the first configuration is the expansion of the catheter frame 424. The first plurality of strands 426 may be wound in a helical direction along the length of the catheter frame 424, and the second plurality of strands 428 may be wound in a counterclockwise direction along the length. The first plurality of strands 426 and the second plurality of strands 428 are configured to be biased for contraction or expansion, and the strands may be configured to slide relative to each other as the catheter frame 424 contracts and expands. The polymer coating 430 is configured to expand and collapse with the conduit frame 424 and extend around the inner surface of the conduit frame 424.

[0042] In some embodiments, the polymer coating 430 includes at least one of ethylene vinyl acetate, polyethylene, polyolefin elastomer, maleic anhydride graft polymer, styrene-butadiene styrene, polypropylene-based elastomer, styrene-butadiene copolymer, thermoplastic polyester elastomer, thermoplastic polyurethane elastomer, thermoplastic vulcanized rubber, polyamide, polytetrafluoroethylene, aromatic polyester, polyvinyl chloride, polymethyl methacrylate, acrylonitrile-butadiene styrene, styrene-acrylonitrile, polystyrene, polyethylene terephthalate copolymer, polycarbonate, polyphenylene ether, polyphenylene ether acetate, butyrate, propionate, polysulfone, polyethersulfone, polyarylsulfone, polybutylene terephthalate, polyester terephthalate, acetal, fluorinated ethylene propylene, perfluoroalkoxy polymer, ethylene chloride trifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene perfluoromethyl vinyl ether, tetrafluoroethylene, hexafluoropropylene, liquid crystal polymer, and polyetheretherketone.

[0043] Catheter 406 can be Figure 1A and Figure 1Bof the catheter 406 and the first medical device coupled to the distal end of the catheter 406 are inserted into the patient's vasculature through the introducer sheath. In further embodiments, the catheter 406 is triggered by the physician to deform into a second configuration in which the catheter frame 424 collapses into a contracted state, where the annular gap is enlarged by the deformation. The enlarged annular gap can be sized to allow a second medical device to be inserted within the introducer sheath and adjacent to the catheter 406. In some embodiments, a blood pump is coupled to the distal end of the catheter 406, and the annular gap in the second configuration is sized to allow a PCI device to be inserted within the same introducer sheath as the catheter 406. The catheter frame 424 can include a braided mesh formed from a first plurality of strands 426 and a second plurality of strands 428. In some embodiments, the catheter frame 424 includes only the first plurality of strands 426. In further embodiments, the catheter frame 424 includes a braided mesh formed only from the first plurality of strands 426. For example, the plurality of strands 426 and 428 can be composed of a polymer, metal, or other material having flexible properties. At least one advantage of the catheter 406 is that the catheter frame 424 can be selectively triggered by the physician to expand or contract with or without the second medical device positioned adjacent to the catheter 406. Another advantage resulting from the design of the catheter 406 is a streamlined structure of the device that does not require the catheter 406 to be divided into multiple components.

[0044] Figure 5A flowchart depicting an exemplary method 500 for introducing a medical device coupled to a collapsible catheter into a patient's vasculature through an introducer sheath is shown. The method 500 includes steps 502 and 504. Step 502 includes percutaneously inserting an introducer sheath into a patient's vasculature, the introducer sheath including a lumen having a fixed diameter and an inner circumference. Step 504 includes introducing a first medical device coupled to a distal end of a catheter through the introducer sheath. The catheter includes a distal end, a proximal end, and an outer circumference sized such that an annular gap is formed between the outer circumference of the catheter and the inner circumference of the lumen of the introducer sheath when the catheter is positioned within the introducer sheath. The catheter is configured to assume a first configuration or a second configuration when positioned within the lumen of the fixed diameter, the catheter having a first dimension in the first configuration and a second dimension in the second configuration. For example, the method can be applied to the system shown in Figure 1A and Figure 1B where the method would include percutaneously inserting the introducer sheath 104 into the vasculature and introducing the first medical device 102 coupled to the catheter 106 through the introducer sheath 104, forming an annular gap between the outer circumference 110 and the inner circumference 112. The catheter in the method 500 can also be the catheter 206, 306, or 406.

[0045] The method 500 can further include a third step including introducing a second medical device into the annular gap, where the annular gap in the second configuration is sized to allow the second medical device to pass therethrough. In some embodiments, the annular gap in the second configuration is larger than the annular gap in the first configuration. In methods 500 using the catheter 206 or 306 in Figure 2 and Figure 3 when the second medical device is passing through the annular gap, and the catheter can be in the first configuration when the second medical device is not in the annular gap. The first medical device can be a blood pump and the second medical device can be a PCI device. In other embodiments where the catheter of the method 500, such as the catheter 406 in Figure 4 is adapted to actively collapse and expand, the method 500 can further include a third step including changing the catheter from the first configuration to the second configuration, where the annular gap in the second configuration is sized to allow the second medical device to pass therethrough. In methods 500 using the catheter 406 from Figure 4In some embodiments of the method 500 of the catheter 406, the physician can trigger the catheter to change its configuration before or after the catheter is inserted into the introducer sheath. In further embodiments, the method 500 further includes a fourth step comprising introducing a second medical device into the annular gap. At least one advantage of the method 500 is that the physician can operate to introduce at least two medical devices into the vasculature of a patient through a single introducer sheath, thereby reducing the management and closure of the access site to one well-defined procedure.

[0046] Figure 6 A flowchart depicting an example method 600 for introducing a blood pump coupled to a collapsible catheter and a PCI device into the vasculature of a patient through an introducer sheath is shown. The method 600 includes steps 602, 604, and 606. Step 602 includes percutaneously inserting an introducer sheath into the vasculature of a patient, the introducer sheath including a lumen having a fixed diameter and an inner circumference. Step 604 includes introducing a blood pump coupled to a distal end of a catheter through the introducer sheath, the catheter having a proximal end and a distal end and an outer circumference sized such that an annular gap is formed between the outer circumference of the catheter and the inner circumference of the lumen of the introducer sheath when the catheter is positioned within the introducer sheath. The catheter is configured to assume a first configuration or a second configuration when positioned within the fixed diameter lumen, the catheter having a first dimension in the first configuration and a second dimension in the second configuration. Step 606 includes introducing a PCI device into the annular gap, the annular gap in the second configuration being sized to allow the second medical device to pass therethrough. The method 600 can be applied to the systems shown and described in FIGS. 1-4. For example, the catheter of the method 600 can be the catheter 106, 206, 306, or 406 inserted within the introducer sheath 104. The change from the first configuration to the second configuration can be achieved by a passive mechanism such as described in Figures 2-3 or by an active mechanism such as described in Figure 4 In some embodiments of the method 600 using the catheter 206 or 306 in Figure 2 and Figure 3 , the catheter is in the second configuration when the second medical device is passing within the annular gap, and the catheter is in the first configuration when the PCI device is not in the annular gap. In other embodiments where the catheter, such as the catheter 406 in Figure 4 , is adapted to actively collapse and expand, the method 600 can further include a third step comprising changing the catheter from the first configuration to the second configuration, where the annular gap in the second configuration is sized to allow the PCI device to pass therethrough. In some embodiments of the method 600 using the catheter 406 from Figure 4In an embodiment of the method 600 of deploying a catheter 406, the physician can trigger the catheter to change its configuration before or after the catheter is inserted into the introducer sheath. At least one advantage of the method 600 is that the physician can perform a high-risk HRPCI through a single introducer sheath that cannot accommodate PCI devices next to the diameter of a fixed-size catheter with the blood pump support coupled to the variable-size catheter.

[0047] Figure 7 A flowchart depicting a method 700 for introducing a medical device coupled to a collapsible catheter through an introducer sheath that already contains a previously inserted medical device is shown. The method 700 includes steps 702, 704, and 706. Step 702 includes percutaneously inserting an introducer sheath into a patient’s vasculature, the introducer sheath including a lumen having a fixed diameter and an inner circumference. Step 704 includes introducing a first medical device into the introducer sheath, the first medical device having an outer circumference sized such that a fixed-size annular gap is formed between the outer circumference of the catheter and the inner circumference of the lumen of the introducer sheath when the first medical device is positioned within the introducer sheath. Step 706 includes introducing a second medical device coupled to a distal end of the catheter into the annular gap, wherein the catheter is configured to assume a first configuration or a second configuration, the catheter having a first dimension in the first configuration and a second dimension in the second configuration, the second configuration configured to fit within the fixed-size annular gap.

[0048] The devices implemented in the method 700 can be the devices described in FIGS. 1-4, for example, using the catheter 106, 206, 306, or 406 and the introducer sheath 104. As the catheter is inserted into the fixed-size annular gap, the catheter can be passively deformed from the first configuration to the second configuration. In other embodiments, the catheter can be actively triggered to deform to the second configuration sized to fit within the fixed-size annular gap. The first medical device can be a PCI device, and the second medical device can be a blood pump. At least one advantage of the method 700 is that the first medical device can be accompanied by the second medical device through the introducer sheath with the aid of a variable-size catheter. For example, the physician can be performing a PCI through the introducer sheath, and then a complication can necessitate a blood pump support for the PCI, so the physician can introduce the blood pump coupled to the variable-size catheter without opening another access point.

[0049] Figure 8A flowchart depicting a method 800 for introducing a medical device coupled to a collapsible catheter, changing a configuration of the catheter, and introducing another medical device alongside the catheter, according to an illustrative embodiment, is shown. The method 800 includes steps 802, 804, 806, and 808. Step 802 includes percutaneously inserting an introducer sheath into a vasculature, the introducer sheath including a lumen having a fixed inner diameter and an inner circumference. Step 804 includes introducing a first medical device coupled to a distal end of a catheter through the introducer sheath, the catheter including a proximal end and an outer circumference having a first dimension, such that when the catheter is positioned within the lumen of the fixed inner diameter, an annular gap exists between the outer circumference of the catheter and the inner circumference of the sheath lumen. Step 806 includes changing the outer circumference of the catheter from the first dimension to a second dimension, such that the annular gap is increased to allow a second medical device to pass therethrough. Step 808 includes introducing the second medical device through the annular gap.

[0050] The devices implemented in the method 800 can be the devices described in Figure 1A 、 Figure 1B and Figure 4 , for example, using the catheter 106 or 406 and the introducer sheath 104. The catheter can be actively changed or triggered by a physician to change from having a first dimension to having a second dimension, thereby changing the annular gap formed between the catheter and the lumen. In some embodiments, the first medical device is a blood pump. In some embodiments, the second medical device is a PCI device, a second introducer sheath, or a second catheter. At least one advantage of the method 800 is that a physician can selectively change the size of the catheter so that a second medical device can be introduced into the vasculature without opening a second access site while the coupled first medical device is in use within the vasculature of a patient. This advantage can be useful, for example, if a complication occurs during a procedure using the first medical device and the physician urgently needs to introduce a second medical device in order to address the complication.

[0051] The foregoing merely illustrates the principles of the disclosure and that which is described and claimed can be practiced in other ways than those

[0052] Changes and modifications will occur to those skilled in the art upon reading of the foregoing description together with the drawings. The disclosed features can be implemented in any combination or sub-combination (including multiple dependent combinations and sub-combinations) of one or more of the other features described herein. The various features described or illustrated above (including any components thereof) can be combined or integrated in other systems. In addition, certain features can be omitted or not implemented.

[0053] The described systems and methods can be implemented locally on a heart pump system or a controller of a heart pump system, such as an AIC. The heart pump system can include a data processing instrument. The systems and methods described herein can be implemented remotely on a separate data processing instrument. The separate data processing instrument can be connected to the heart pump system directly or indirectly through a cloud application. The heart pump system can communicate in real-time (or near real-time) with the separate data processing instrument.

[0054] In general, the various embodiments of the subject matter described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them.

[0055] Examples of changes, substitutions and alterations can be determined by one skilled in the art and can be made without departing from the scope of the information disclosed herein. All references cited herein are incorporated by reference in their entirety and form a part of the present application.

Claims

1. An intravascular system for inserting a first medical device and a second medical device into a vasculature of a patient, the system comprising: an introducer sheath configured to be percutaneously inserted into the vasculature, the introducer sheath including a lumen having a fixed inner diameter and a fixed inner circumference; a first medical device; and a catheter including: a proximal end, a distal end, wherein the distal end is coupled to the first medical device, an inner layer and an outer layer, wherein at least one of the inner layer or the outer layer is removably attached to the catheter, and a portion of an outer circumference configured to adjustably assume a first dimension or a second dimension when positioned within the lumen of the introducer sheath upon removal of the inner layer or the outer layer such that the catheter can be positioned within the lumen of the introducer sheath and leave an annular gap between the outer circumference of the catheter and the inner circumference of the lumen of the introducer sheath, wherein the portion of the outer circumference of the catheter extends over an entire length of the catheter configured to be positioned within the lumen of the introducer sheath.

2. The system of claim 1, wherein the catheter is configured such that the annular gap when the outer circumference of the catheter assumes the second dimension is sized to allow the second medical device to pass therethrough.

3. The system of any one of claims 1 or 2, wherein the catheter is configured such that the annular gap when the outer circumference of the catheter assumes the second dimension is greater than the annular gap when the outer circumference of the catheter assumes the first dimension.

4. The system of claim 2, wherein the outer circumference of the catheter is configured to: assume the second dimension when the second medical device is within the annular gap; and assume the first dimension when the second medical device is not in the annular gap.

5. The system of any one of claims 1-2, wherein the first medical device further comprises a blood pump.

6. The system of any one of claims 1-2, wherein the second medical device comprises a percutaneous coronary intervention device.

7. The system of claim 1, wherein: the outer layer is flexible; and the inner layer is rigid.

8. The system of claim 1, wherein the outer circumference of the catheter is configured to change from the first dimension to the second dimension upon removal of the inner layer.

9. The system of claim 1, wherein: the inner layer is flexible; and the outer layer is rigid.

10. The system of claim 1, wherein the outer circumference of the catheter is configured to change from the first dimension to the second dimension upon removal of the outer layer.

11. The system of any one of claims 8 or 10, wherein the inner layer or the outer layer is configured to be removed in a proximal direction.

12. The system of claim 1, wherein the inner layer or the outer layer includes at least one peel-away slit that allows removal of the inner layer or the outer layer. ​ 13. The system of claim 2, wherein the second medical device exerts a normal force on an outer surface of the catheter when the second medical device is introduced into the introducer sheath, the normal force constraining the outer circumference of the catheter to the second dimension.

14. The system of claim 2, wherein the catheter comprises a polymer.

15. The system of claim 14, wherein the polymer comprises at least one of ethylene vinyl acetate, polyethylene, polyolefin elastomer, maleic anhydride grafted polymer, styrene butadiene styrene, polypropylene-based elastomer, styrene butadiene copolymer, thermoplastic polyester elastomer, thermoplastic polyurethane elastomer, thermoplastic vulcanizate, polyamide, polytetrafluoroethylene, aromatic polyester, polyvinyl chloride, polymethyl methacrylate, acrylonitrile butadiene styrene, styrene acrylonitrile, polystyrene, polyethylene terephthalate copolymer, polycarbonate, polyphenylene ether, polyphenylene ether, acetate, butyrate, propionate, polysulfone, polyether sulfone, polyaryl sulfone, polybutylene terephthalate, polyester terephthalate, acetal, fluorinated ethylene propylene, perfluoroalkoxy polymer, ethylene chlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene perfluoromethyl vinyl ether, tetrafluoroethylene, hexafluoropropylene, liquid crystal polymer, and polyether ether ketone.

16. An intravascular system for inserting a first medical device and a second medical device into a vasculature of a patient, the system comprising: an introducer sheath configured to be inserted percutaneously into the vasculature, the introducer sheath including a lumen having a fixed inner diameter and a fixed inner circumference; a first medical device; and a catheter including: a proximal end, a distal end, wherein the distal end is coupled to the first medical device, a portion of an outer circumference configured to adjustably assume a first dimension or a second dimension when positioned within the lumen of the introducer sheath such that the catheter is positionable within the lumen of the introducer sheath and leaves an annular gap between the outer circumference of the catheter and the inner circumference of the lumen of the introducer sheath, wherein the portion of the outer circumference of the catheter extends over an entire length of the catheter, the catheter is configured to be positioned within the lumen of the introducer sheath, and a catheter frame configured to reversibly deform the portion of the outer circumference of the catheter from the first dimension to the second dimension.

17. The system of claim 16, further comprising a polymer layer covering an outer circumference of the catheter frame and forming a coating around an outer surface of the catheter frame.

18. The system of claim 17, wherein the catheter frame is configured to collapse and expand, wherein: the collapse of the catheter frame includes a change from the first dimension to the second dimension; and the expansion of the catheter frame includes a change from the second dimension to the first dimension, wherein the polymer layer is configured to expand and collapse with the catheter frame.

19. The system of claim 16, wherein the catheter comprises a plurality of strands: the plurality of strands are configured with a bias to contract or expand; and the plurality of strands extend longitudinally between the proximal end and the distal end.

20. The system of claim 19, wherein the catheter is configured to permit the strands to slide relative to one another when the catheter frame contracts and expands.

21. The system of claim 17, wherein the coating extends around an inner surface of the catheter frame.

22. The system of claim 16, wherein the catheter frame comprises a braided mesh formed from a first plurality of strands, the first plurality of strands being wrapped in a helical direction along a length of the catheter frame.

23. The system of claim 22, wherein the catheter frame comprises a second plurality of strands, the second plurality of strands being wrapped in a counterclockwise direction along the length.

24. The system of claim 1, wherein: the first dimension is between 9 Fr and 10 Fr; and the second dimension is greater than 7 Fr and less than 9 Fr.

25. The system of claim 1, wherein a first portion of the catheter is within the lumen of the introducer sheath and a second portion of the catheter is not within the lumen of the introducer sheath.

26. The system of claim 25, wherein the first portion of the catheter changes from the first dimension to the second dimension while the second portion of the catheter remains at the first dimension.

27. The system of claim 2, wherein the second dimension allows the catheter and the second medical device to fit within the lumen of the introducer sheath and adjacent to one another.

28. The system of claim 1, wherein the first dimension and the second dimension are measurements of a length of a cross-section of the catheter.

29. The system of claim 28, wherein the cross-section of the catheter is circular and the first dimension and the second dimension are diameters of the circular cross-section.

30. The system of claim 28, wherein the cross-section of the catheter is not circular and the first dimension and the second dimension are widths of the cross-section in one direction.

31. An intravascular system for inserting a blood pump and a percutaneous coronary intervention device into a vasculature of a patient, the system comprising: an introducer sheath configured to be percutaneously inserted into the vasculature, the introducer sheath comprising a lumen having a fixed inner diameter and inner circumference; a blood pump; and a catheter comprising: a proximal end, a distal end, wherein the distal end is coupled to the blood pump, an inner layer and an outer layer, wherein at least one of the inner layer or the outer layer is removably attached to the catheter, and a first dimension of the catheter is less than the inner diameter of the lumen of the introducer sheath. a portion of an outer circumference of the catheter, the portion of the outer circumference configured to adjustably assume a first dimension or a second dimension when positioned within the lumen of the introducer sheath upon removal of the inner layer or the outer layer, such that the catheter is positionable within the lumen of the introducer sheath and leaves an annular gap between the outer circumference of the catheter and the inner circumference of the lumen of the introducer sheath, wherein the portion of the outer circumference of the catheter extends over an entire length of the catheter, the catheter configured to be positioned within the lumen of the introducer sheath.

32. The system of claim 31, wherein the catheter is configured such that the annular gap when the outer circumference of the catheter assumes the second dimension is sized to allow passage therethrough of a percutaneous coronary intervention device.

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