A percutaneous circulatory assist device including a proximal pressure sensor

Abstract

The percutaneous circulatory assist device includes a housing and an impeller disposed within the housing. The impeller is configured to rotate relative to the housing to allow blood to flow through the housing. A motor is operably coupled to the impeller, and the motor is configured to rotate the impeller relative to the housing. A catheter is coupled to the motor. A collar is coupled to the catheter and is disposed proximally relative to the housing. The collar includes an internal chamber, and a pressure sensor is disposed within the internal chamber of the collar.

Description

Technical Field

[0001] The present disclosure relates to a percutaneous circulatory assist system. More specifically, the present disclosure relates to a percutaneous circulatory assist device including one or more pressure sensors.

Background Art

[0002] Percutaneous circulatory assist devices can provide temporary assistance for up to about several weeks in patients with reduced cardiac function or cardiac output. Some percutaneous circulatory assist devices include one or more pressure sensors for measuring intravascular pressure. By measuring these pressures, for example, (1) it is possible to detect a change in the unintended device position within the heart, and (2) it is possible to determine cardiac output, and thus it is possible to evaluate potential treatment changes. However, devices including pressure sensors have several drawbacks. For example, the pressure sensor may be damaged during deployment. As another example, the sensed pressure may be inaccurate due to the operating speed of the device and the influence of other dynamic pressures. Therefore, an improved device including a pressure sensor is needed.

Summary of the Invention

[0003] In Example 1, a percutaneous circulatory assist device includes a housing and an impeller disposed within the housing. The impeller is configured to rotate relative to the housing to allow blood to flow through the housing. A motor is operably coupled to the impeller, and the motor is configured to rotate the impeller relative to the housing. A catheter is coupled to the motor. A collar is coupled to the catheter and is disposed proximally relative to the housing. The collar includes an internal chamber, and a pressure sensor is disposed within the internal chamber of the collar.

[0004] In Example 2, in the percutaneous circulatory assist device of Example 1, the collar further includes an opening coupled to the internal chamber. In Example 3, in the percutaneous circulatory assist device of Example 2, the opening is a distally facing opening.

[0005] In Example 4, in the percutaneous circulatory assist device of Example 2 or 3, the collar further includes an outer surface, and the outer surface includes a tapered distal portion that forms the opening. In Example 5, in the percutaneous circulatory assist device of Example 4, the outer surface further includes a tapered proximal portion.

[0006] In Example 6, in the percutaneous circulatory assist device of Example 5, the tapered distal portion has a first slope, the tapered proximal portion has a second slope, and the first slope is greater than the second slope.

[0007] In Example 7, in the percutaneous circulatory assist device of Example 5 or 6, the outer surface further includes a cylindrical surface between the tapered distal portion and the tapered proximal portion. In Example 8, in the percutaneous circulatory assist device of Example 2, the opening is a laterally facing opening.

[0008] In Example 9, in the percutaneous circulatory assist device of Example 8, the collar further includes a distally facing opening coupled to the internal chamber. In Example 10, in the percutaneous circulatory assist device of Example 8 or 9, the laterally facing opening is a first laterally facing opening, and the collar further includes a second laterally facing opening coupled to the internal chamber.

[0009] In Example 11, in the percutaneous circulatory assist device of Example 2, the opening extends at an acute angle with respect to the longitudinal axis of the internal chamber. In Example 12, any one of the percutaneous circulatory assist devices of Examples 1 to 11 further includes a sensor mount disposed within the internal chamber of the collar and coupled to a pressure sensor.

[0010] In Example 13, the percutaneous circulatory assist device includes a housing and an impeller disposed within the housing. The impeller is configured to rotate relative to the housing to allow blood to flow through the housing. A motor is operably coupled to the impeller, and the motor is configured to rotate the impeller relative to the housing. A catheter is coupled to the motor, and a collar is coupled to the catheter and is disposed proximally relative to the housing. The collar includes an internal chamber, a distally directed opening coupled to the internal chamber, and a proximally directed opening coupled to the internal chamber. A pressure sensor is disposed within the internal chamber of the collar. A sensor cable is coupled to the pressure sensor, and the sensor cable extends through the proximally directed opening.

[0011] In Example 14, in the percutaneous circulatory assist device of Example 13, the pressure sensor includes one of an optical pressure sensor and an electrical pressure sensor. In Example 15, in the percutaneous circulatory assist device of Example 13 or 14, the pressure sensor is disposed at least 0.00254 centimeters (0.001 inches) away from the outer surface of the catheter.

[0012] In Example 16, the percutaneous circulatory assist device includes a housing having an inlet and an outlet. An impeller is disposed within the housing, and the impeller is configured to rotate relative to the housing to allow blood to flow into the inlet and out of the outlet through the housing. A motor is operably coupled to the impeller, and the motor is configured to rotate the impeller relative to the housing. A catheter is coupled to the motor. A collar is coupled to the catheter and is disposed proximally relative to the housing, and the collar includes an internal chamber. A pressure sensor is disposed within the internal chamber of the collar.

[0013] In Example 17, in the percutaneous circulatory assist device of Example 16, the collar further includes an opening coupled to the internal chamber. In Example 18, in the percutaneous circulatory assist device of Example 17, the opening is a distally directed opening.

[0014] In Example 19, in the percutaneous circulatory assist device of Example 18, the collar further includes an outer surface, and the outer surface includes a tapered distal portion that forms a distally directed opening. In Example 20, in the percutaneous circulatory assist device of Example 17, the opening is a laterally directed opening.

[0015] In Example 21, in the percutaneous circulatory assist device of Example 20, the collar further includes a distally directed opening coupled to the internal chamber. In Example 22, in the percutaneous circulatory assist device of Example 20, the laterally directed opening is a first laterally directed opening, and the collar further includes a second laterally directed opening coupled to the internal chamber.

[0016] In Example 23, in the percutaneous circulatory assist device of Example 17, the opening extends at an acute angle with respect to the longitudinal axis of the internal chamber. In Example 24, the percutaneous circulatory assist device of Example 17 further includes a sensor mount disposed within the internal chamber of the collar and coupled to a pressure sensor.

[0017] In Example 25, in the percutaneous circulatory assist device of Example 24, the pressure sensor is adhered to the sensor mount. In Example 26, the percutaneous circulatory assist device of Example 17 further includes a sensor cable coupled to the pressure sensor.

[0018] In Example 27, in the percutaneous circulatory assist device of Example 17, the collar further includes a proximally directed opening coupled to the internal chamber, and the sensor cable extends through the proximally directed opening.

[0019] In Example 28, in the percutaneous circulatory assist device of Example 27, the collar further includes an outer surface, and the outer surface includes a tapered proximal portion that forms a proximally directed opening. In Example 29, in the percutaneous circulatory assist device of Example 17, the collar further includes an outer surface, and the outer surface includes a tapered distal portion and a tapered proximal portion.

[0020] In Example 30, in the percutaneous circulatory assist device of Example 29, the tapered distal portion has a first slope, the tapered proximal portion has a second slope, and the first slope is greater than the second slope.

[0021] In Example 31, in the percutaneous circulatory assist device of Example 17, the pressure sensor includes one of an optical pressure sensor and an electrical pressure sensor. In Example 32, the percutaneous circulatory assist device includes a housing that includes an inlet and an outlet. The impeller is disposed within the housing and is configured to rotate relative to the housing so that blood flows into the inlet and outflows from the outlet through the housing. The motor is operably coupled to the impeller and is configured to rotate the impeller relative to the housing. The catheter is coupled to the motor. The collar is coupled to the catheter and is disposed proximally relative to the housing. The collar includes an internal chamber, a distally directed opening coupled to the internal chamber, and a proximally directed opening coupled to the internal chamber. The pressure sensor is disposed within the internal chamber of the collar. The sensor cable is coupled to the pressure sensor and extends through the proximally directed opening.

[0022] In Example 33, in the percutaneous circulatory assist device of Example 32, the pressure sensor is disposed at least 0.00254 centimeters (0.001 inches) away from the outer surface of the catheter.

[0023] In Example 34, a method for manufacturing a percutaneous circulatory assist device includes disposing an impeller within a housing such that the impeller is rotatable relative to the housing, operably coupling a motor to the impeller, coupling a catheter to the motor, coupling a pressure sensor to a collar, and then coupling the collar and the pressure sensor to the catheter proximal to the motor.

[0024] In Example 35, in the method of Example 34, coupling the collar and the pressure sensor to the catheter includes advancing the collar and the pressure sensor distally along the catheter.

[0025] Although multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those of ordinary skill in the art from the following detailed description, which illustrates and describes exemplary embodiments of the invention. The drawings and the detailed description are to be regarded as illustrative in nature and not restrictive.

Brief Description of the Drawings

[0026]

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DETAILED DESCRIPTION OF THE INVENTION

[0027] The present invention can accept various modifications and alternative forms, but specific embodiments are shown by way of example in the drawings and will be described in detail below. However, the intention is not to limit the present invention to the specific embodiments described. On the contrary, the present invention is intended to embrace all modifications, equivalents, and alternative forms included within the scope of the present invention as defined by the appended claims.

[0028] FIG. 1 shows a partial side cross-sectional view of an exemplary percutaneous circulatory assist device 100 (also referred to interchangeably herein as a “blood pump”) according to an embodiment of the subject matter disclosed herein. The device 100 can form part of a percutaneous circulatory assist system together with a guide wire and an introducer sheath (not shown). More specifically, the guide wire and the introducer sheath can enable percutaneous delivery of the device 100 to a target location within a patient, such as within the patient's heart. Alternatively, the device 100 can be delivered to different target locations within the patient.

[0029] Continuing to refer to FIG. 1, device 100 generally includes a housing 101 that includes an impeller housing 102 and a motor housing 104. In some embodiments, impeller housing 102 and motor housing 104 may be constructed integrally or monolithically. In other embodiments, impeller housing 102 and motor housing 104 may be separate components configured to be removably or permanently coupled. In some embodiments, blood pump 100 may not include a separate motor housing 104, and impeller housing 102 may be directly coupled to motor 105 described below, or motor housing 104 may be constructed integrally with motor 105 described below.

[0030] The impeller housing 102 houses an impeller assembly 106 therein. The impeller assembly 106 includes an impeller shaft 108 that is rotatably supported by at least one bearing such as a bearing 110. The impeller assembly 106 also includes an impeller 112 that rotates relative to the impeller housing 102 to pump blood through the device 100. More specifically, the impeller 112 causes blood to flow from a blood inlet 114 (FIG. 1) formed on the impeller housing 102, through the impeller housing 102, and out of a blood outlet 116 formed on the impeller housing 102. In some embodiments, as illustrated, the impeller shaft 108 and the impeller 112 can be separate components, and in other embodiments, the impeller shaft 108 and the impeller 112 can be integral. In some embodiments, as illustrated, the inlet 114 and / or the outlet 116 can each include a plurality of openings. In other embodiments, the inlet 114 and / or the outlet 116 can each include a single opening. In some embodiments, as illustrated, the inlet 114 can be formed at an end of the impeller housing 102, and the outlet 116 can be formed at a side of the impeller housing 102. In other embodiments, the inlet 114 and / or the outlet 116 can be formed at other portions of the impeller housing 102. In some embodiments, the impeller housing 102 can be coupled to a distally extending cannula (not shown) that can receive blood and deliver it to the inlet 114.

[0031] Continuing to refer to FIG. 1, the motor housing 104 houses the motor 105, and the motor 105 is configured to rotatably drive the impeller 112 with respect to the impeller housing 102. In the illustrated embodiment, the motor 105 rotates the drive shaft 120 coupled to the drive magnet 122. The rotation of the drive magnet 122 causes the rotation of the driven magnet 124, which is connected to the impeller assembly 106 and rotates with the impeller assembly 106. More specifically, in an embodiment incorporating the impeller shaft 108, the impeller shaft 108 and the impeller 112 are configured to rotate with the driven magnet 124. In other embodiments, the motor 105 may be coupled to the impeller assembly 106 via other components.

[0032] In some embodiments, a controller (not shown) may be operably coupled to the motor 105 and configured to control the motor 105. In some embodiments, the controller may be disposed within the motor housing 104. In other embodiments, the controller may be disposed outside the motor housing 104 (e.g., within a separate housing, etc.). In some embodiments, the controller may include a plurality of components, one or more of which may be disposed within the motor housing 104. According to an embodiment, the controller may be one or more field programmable gate arrays (FPGAs), one or more programmable logic devices (PLDs), one or more complex PLDs (CPLDs), one or more custom application specific integrated circuits (ASICs), one or more dedicated processors (e.g., microprocessors), one or more central processing units (CPUs), software, hardware, firmware, or any combination of these and / or other components, may include them, or may be included in them. Although the controller is referred to herein in the singular, the controller may be implemented in multiple instances, may be distributed across multiple computing devices, may be instantiated within multiple virtual machines, and / or may be similar. In other embodiments, the motor 105 may be controlled in other ways.

[0033] Continuing to refer to FIG. 1 and further referring to FIG. 2, the motor housing 104 is coupled to the catheter 126 on the side opposite the impeller housing 102. The catheter 126 can be coupled to the motor housing 104 by various methods such as laser welding, soldering, adhesive bonding, thermal polymer reflowing, or similar methods. The catheter 126 extends proximally away from the motor housing 104. The catheter 126 holds the motor cable 128 within the main lumen 130, and the motor cable 128 can operably couple the motor 105 to a controller (not shown) and / or an external power source (not shown). Externally, the catheter 126 carries a sensor assembly 132 for measuring pressure within a patient's vasculature, for example, within the aorta. Advantageously, the sensor assembly 132 is positioned at a location for obtaining very accurate pressure data with respect to other components of the device 100. For example, the proximal position of the sensor assembly 132 with respect to the motor housing 104 and the motor 105 reduces or eliminates sensor inaccuracies related to motor speed or dynamic pressure. Such inaccuracies are typical of other percutaneous circulatory assist devices that employ pressure sensors located more distally with respect to the motor or impeller assembly, for example, devices that employ pressure sensors located near the outlet.

[0034] Referring particularly to FIG. 2, the sensor assembly 132 includes a sensor housing 134 having a counterbore-shaped internal chamber 136. A pressure sensor 138, such as an optical pressure sensor or an electrical pressure sensor, is disposed within the internal chamber 136. Thus, the sensor housing 134 protects the pressure sensor 138 during deployment of the device 100. The sensor housing 134 also includes a distally-directed opening 140 coupled to the internal chamber 136. The opening 140 permits blood to enter the internal chamber 136, thereby enabling the pressure sensor 138 to sense the pressure of the blood.

[0035] The sensor housing 134 can take various forms. For example, the sensor housing 134 can be a tube or ferrule made of, for example, one or more metals, one or more plastics, composite materials, or the like. The sensor housing 134 can be coupled to the catheter 126 via one or more welds (not shown), one or more adhesives 142, and / or an outer jacket 144 surrounding the sensor housing 134 and the catheter 126. Also, the sensor housing 134 can include a sensor mount 146 within the internal chamber 136. The sensor mount 146 enables the pressure sensor 138 to be supported away from the wall of the sensor housing 134 (i.e., the sensor mount 146 positions the pressure sensor 138 at the center within the internal chamber 136), thereby enabling high-precision pressure sensing.

[0036] Continuing to refer to FIG. 2, the sensor assembly 132 further includes a sensor cable 148 coupled to the pressure sensor 138. The sensor cable 148 can operably couple the pressure sensor to a controller (not shown). As shown, the sensor cable 148 extends through the sensor mount 146 and can support the pressure sensor 138 away from the wall of the sensor housing 134. The sensor cable 148 penetrates the adhesive 142 and extends proximally through a cable lumen 150 coupled to the catheter 126. The cable lumen 150 can be coupled to the catheter 126 via one or more welds (not shown), an adhesive (not shown), and / or the outer jacket 144. In other embodiments, the cable lumen 150 can be omitted, and the sensor cable 148 can extend through the main lumen 130 of the catheter 126 or can be laid under the outer jacket 144.

[0037] Figures 3 and 4 show another sensor assembly 200 according to an embodiment of the subject matter disclosed herein. The sensor assembly 200 can be used as part of the percutaneous circulatory assist device 100 instead of the sensor assembly 132 described above. The sensor assembly 200 is similar to the sensor assembly 132 described above. More specifically, the sensor assembly 200 includes a sensor housing 202 having an internal chamber 204, a pressure sensor 206, a sensor cable 208 (FIG. 4), and any sensor mount 210 (FIG. 4) disposed within the internal chamber 204. The sensor housing 202 also includes a plurality of openings coupled to the internal chamber 204. More specifically, the sensor housing 202 includes a distally facing opening 212, a first laterally facing opening 214, and a second laterally facing opening 216 (FIG. 4). The plurality of openings facilitate blood flow through the sensor housing 202, thereby reducing thrombus formation. Alternatively, the sensor housing 202 can include a different number of openings. For example, the sensor housing 202 can include one or more laterally facing openings and omit the distally facing opening. In either case, each of the openings can be sized, for example, to prevent the sensor 206 from passing through the opening in the event that the sensor 206 becomes detached from the sensor cable 208 during use. Also, the openings can have an oval shape as shown in FIG. 3, or various other shapes.

[0038] In some embodiments, as shown in FIGS. 3 and 4, the distally facing opening 212 is formed by a tapered portion 218 of the sensor housing 202. The tapered portion 218 can be formed by crimping or bonding a separate member to the remainder of the sensor housing 202. In other embodiments, the distally facing opening 212 can be a flat feature perpendicular to the axis of the internal chamber 204. In other embodiments, the tapered portion 218 may be created using a countersinking process from the proximal end of the sensor housing 202.

[0039] In some embodiments, as shown in FIGS. 3 and 4, sensor 206 is at least partially aligned with a first laterally oriented opening 214 and a second laterally oriented opening 216. This position of sensor 206 makes the space within sensor housing 202 where air bubbles that could potentially reduce sensing accuracy may form relatively small. Alternatively, sensor 206 may be disposed at other locations within sensor housing 202. In some embodiments, sensor 206 includes a surface energy reduction coating (not shown), such as silicone, to suppress air bubble formation on or within sensor 206.

[0040] FIG. 5 shows a partial cross-sectional view of an exemplary percutaneous circulatory assist system 300 according to an embodiment of the subject matter disclosed herein. The system 300 includes a percutaneous circulatory assist device 302 similar to the device 100 described above. More specifically, the distal portion (not shown) of the device 302 generally includes an impeller housing and an impeller, such as the impeller housing 102 and the impeller 112, respectively, described above and shown elsewhere. The proximal portion of the device 302 includes a motor housing 304 that houses a motor 306, and the motor housing 304 is coupled to a catheter 308 on the side opposite the motor 306. The catheter 308 extends proximally away from the motor housing 304. The catheter 308 holds a motor cable 310 within a main lumen 312, and the motor cable 310 can operably couple the motor 306 to a controller (not shown) and / or an external power source (not shown). Externally, the catheter 308 holds a guide wire lumen 314 that receives a pressure sensing guide wire 316. The pressure sensing guide wire 316 can be operably coupled to a controller, and the guide wire 316 can take various specific forms. However, referring further to FIG. 6, the pressure sensing guide wire 316 generally includes an elongate flexible body 318 that holds a pressure sensor 320, such as an optical sensor or an electrical pressure sensor. The pressure sensing guide wire 316 is advanced from a proximal end (not shown) of the guide wire lumen 314 to a distal end 322 of the guide wire lumen 314 (either before or after the device 302 is placed within the patient's vasculature). The sensor 320 extends distally from the guide wire lumen 314 and is disposed within a sensing region 324 of the catheter 308. The sensing region 324 is located proximally from the motor housing 304 and the motor 306, which, as described above, enables obtaining very accurate pressure data. The guide wire 316 can additionally or alternatively sense pressures at various other locations with respect to the catheter 308.

[0041] In other embodiments, system 300 may take other forms or include additional components. For example, device 302 may include a sensor housing, such as sensor housing 134 or sensor housing 202 described above and shown elsewhere, to receive and protect pressure sensor 320 of guidewire 316. Such a sensor housing may be coupled to catheter 308 in various ways, including the methods described above in connection with catheter 126 and sensor housing 134 or sensor housing 202. As another example, guidewire 316 may be fixed relative to catheter 126.

[0042] A method of manufacturing percutaneous circulatory assist device 100 is as follows, and the method of manufacturing device 302 is similar. Impeller 112 is disposed within impeller housing 102 such that impeller 112 is rotatable relative to impeller housing 102. Impeller 112 is operably coupled to motor 105, and catheter 126 is disposed adjacent motor housing 104. Cable lumen 150 is disposed adjacent catheter 126 and coupled to catheter 126 via a process that may include forming outer jacket 144 by at least one polymer reflow process. Next, pressure sensor 138 and sensor cable 148 are coupled to sensor housing 134 such that sensor 138 is disposed within internal chamber 136 of sensor housing 134. Sensor cable 148 is disposed within cable lumen 150, and sensor housing 134 and pressure sensor 138 within sensor housing 134 are disposed adjacent catheter 126. Sensor housing 134 and pressure sensor 138 within sensor housing 134 are coupled to catheter 126 via one or more of, for example, welding, adhesion, and coating of the above-described components by outer jacket 144. Coating these components with outer jacket 144 may include forming outer jacket 144 by a polymer reflow process.

[0043] FIG. 7 shows a partial side cross-sectional view of an exemplary percutaneous circulatory assist device 400 (also interchangeably referred to herein as a “blood pump”) according to an embodiment of the subject matter disclosed herein. The device 400 can form part of a percutaneous circulatory assist system, together with a guide wire and introducer sheath (not shown). More specifically, the guide wire and introducer sheath can enable percutaneous delivery of the device 400 to a target location within a patient, such as within the patient's heart. Alternatively, the device 400 can be delivered to a different target location within the patient.

[0044] Continuing to refer to FIG. 7, the device 400 generally includes a housing 401 that includes an impeller housing 402 and a motor housing 404. In some embodiments, the impeller housing 402 and the motor housing 404 can be constructed integrally or monolithically. In other embodiments, the impeller housing 402 and the motor housing 404 can be separate components configured to be removably or permanently coupled. In some embodiments, the blood pump 400 may not include a separate motor housing 404, and the impeller housing 402 can be directly coupled to a motor 405 described below, or the motor housing 404 can be constructed integrally with the motor 405 described below.

[0045] The impeller housing 402 houses an impeller assembly 406 therein. The impeller assembly 406 includes an impeller shaft 408 that is rotatably supported by at least one bearing such as a bearing 410. Further, the impeller assembly 406 includes an impeller 412 that rotates with respect to the impeller housing 402 and pumps blood through the device 400. More specifically, the impeller 412 causes blood to flow out from a blood inlet 414 (FIG. 7) formed on the impeller housing 402, through the impeller housing 402, and out of a blood outlet 416 formed on the impeller housing 402. In some embodiments, as illustrated, the impeller shaft 408 and the impeller 412 can be separate components, and in other embodiments, the impeller shaft 408 and the impeller 412 can be integral. In some embodiments, as illustrated, the inlet 414 and / or the outlet 416 can each include a plurality of openings. In other embodiments, the inlet 414 and / or the outlet 416 can each include a single opening. In some embodiments, as illustrated, the inlet 414 can be formed at an end of the impeller housing 402, and the outlet 416 can be formed at a side of the impeller housing 402. In other embodiments, the inlet 414 and / or the outlet 416 can be formed at other portions of the impeller housing 402. In some embodiments, the impeller housing 402 can be coupled to a distally extending cannula (not shown), and the cannula can receive blood and deliver it to the inlet 414.

[0046] Continuing to refer to FIG. 7, the motor housing 404 houses the motor 405, and the motor 405 is configured to rotatably drive the impeller 412 with respect to the impeller housing 402. In the illustrated embodiment, the motor 405 rotates a drive shaft 420 coupled to a drive magnet 422. The rotation of the drive magnet 422 causes the rotation of a driven magnet 424 that is connected to the impeller assembly 406 and rotates with the impeller assembly 406. More specifically, in an embodiment incorporating the impeller shaft 408, the impeller shaft 408 and the impeller 412 are configured to rotate with the driven magnet 424. In other embodiments, the motor 405 may be coupled to the impeller assembly 406 via other components.

[0047] In some embodiments, a controller (not shown) may be operably coupled to motor 405 and configured to control motor 405. In some embodiments, the controller may be disposed within motor housing 404. In other embodiments, the controller may be disposed outside of motor housing 404 (e.g., within a separate housing, etc.). In some embodiments, the controller may include a plurality of components, one or more of which may be disposed within motor housing 404. According to an embodiment, the controller may be one or more field programmable gate arrays (FPGAs), one or more programmable logic devices (PLDs), one or more complex PLDs (CPLDs), one or more custom application specific integrated circuits (ASICs), one or more dedicated processors (e.g., microprocessors), one or more central processing units (CPUs), software, hardware, firmware, or any combination of these and / or other components, may include them, or may be included by them. Although the controller is referred to herein in the singular, the controller may be implemented in multiple instances, may be distributed across multiple computing devices, may be instantiated within multiple virtual machines, and / or the like. In other embodiments, motor 405 may be controlled in other ways.

[0048] Continuing to refer to FIG. 7 and further referring to FIG. 8, the motor housing 404 is coupled to the catheter 426 on the side opposite the impeller housing 402. The catheter 426 can be coupled to the motor housing 404 by various methods such as laser welding, soldering, or similar methods. The catheter 426 extends proximally away from the motor housing 404. The catheter 426 holds the motor cable 428 within the main lumen 430, and the motor cable 428 can operably couple the motor 405 to a controller (not shown) and / or an external power source (not shown). Externally, the catheter 426 houses a sensor assembly 432 for measuring the pressure within the patient's vasculature, for example, within the aorta. Advantageously, the sensor assembly 432 is positioned in a location for obtaining very accurate pressure data relative to the other components of the device 400. For example, the proximal position of the sensor assembly 432 relative to the motor housing 404 and the motor 405 reduces or eliminates sensor inaccuracies related to motor speed or dynamic pressure. Such inaccuracies are typical of other percutaneous circulatory assist devices that employ a pressure sensor located more distally relative to the motor or impeller assembly, for example, devices that employ a pressure sensor located near the outlet.

[0049] Referring specifically to FIG. 8, the sensor assembly 432 includes a collar 434 having a countersunk internal chamber 436. A pressure sensor 438, such as an optical pressure sensor or an electrical pressure sensor, is disposed within the internal chamber 436. Thus, the collar 434 protects the pressure sensor 438 during deployment of the device 400. The collar 434 also includes a distally directed opening 440 coupled to the internal chamber 436. The opening 440 permits blood to enter the internal chamber 436, thereby enabling the pressure sensor 438 to sense the pressure of the blood. The collar 434 further includes a laterally directed opening 441, and the distally directed opening 440 and the laterally directed opening 441 allow blood flow through the collar 434, thereby reducing thrombus formation. In some embodiments, the collar 434 includes one or more additional openings, such as laterally directed openings. Such openings may be formed at different angles on the collar 434 to promote blood flow. More specifically, such openings may extend obliquely or at an acute angle with respect to the longitudinal axis of the internal chamber 436. Such openings can have various shapes, such as circular, cylindrical, or the opening may be an elongated slot.

[0050] The collar 434 extends at least partially around the catheter 426. The collar 434 can be coupled to the catheter 426 via an outer jacket (not shown) that at least partially surrounds the collar 434 and the catheter 426, crimping, one or more adhesives, and / or one or more welds (not shown).

[0051] Continuing to refer to FIG. 8 and further referring to FIG. 9, the collar 434 may also house a sensor mount 446 within the internal chamber 436. The sensor mount 446 enables the pressure sensor 438 to be supported away from the wall of the collar 434 (i.e., the sensor mount 446 positions the pressure sensor 438 at the center within the internal chamber 436), thereby enabling high-precision pressure sensing. The pressure sensor 438 can be adhered to the sensor mount 446.

[0052] Continuing to refer to FIGS. 8 and 9, sensor assembly 432 further includes a sensor cable 448 coupled to pressure sensor 438. Sensor cable 448 can operably couple the pressure sensor to a controller (not shown). As shown, sensor cable 448 can extend through an opening 449 (FIG. 8) proximal to sensor mount 446 and collar 434.

[0053] Referring again to FIG. 8, collar 434 supports pressure sensor 438 relatively distant from outer surface 451 of catheter 426 where blood flow is relatively slow. As a result, collar 434 promotes blood flow through collar 434, thereby reducing thrombus formation. In some embodiments, pressure sensor 438 is disposed at least 0.00762 centimeters (0.003 inches), more specifically at least 0.00254 centimeters (0.001 inches) away from outer surface 451 of catheter 426.

[0054] Continuing to refer to FIG. 8, the outer surface 452 of the collar 434 can be shaped to prevent vortex formation in the blood flow in the vicinity of the collar 434. More specifically, the outer surface 452 of the collar 434 can include a tapering distal portion 454 and a tapering proximal portion 456. The tapering distal portion 454 and the tapering proximal portion 456 can be separated by a non-tapering or cylindrical portion 458. As shown, the tapering distal portion 454 can form a distally-directed opening 440, and the tapering proximal portion 456 can form a proximally-directed opening 449. The tapering distal portion 454 may have a greater (steeper) slope than the tapering proximal portion 456. In other words, the tapering distal portion 454 has a first slope, the tapering proximal portion 456 has a second slope, and the first slope may be greater than the second slope. In other embodiments, the outer surface 452 of the collar 434 may have a different shape. For example, the tapering distal portion 454 and the tapering proximal portion 456 may have equal slopes.

[0055] A method of manufacturing the percutaneous circulatory assist device 400 is as follows. The impeller 412 is disposed within the impeller housing 402 such that the impeller 412 is rotatable relative to the impeller housing 402. The impeller 412 is operably coupled to the motor 405, and the catheter 426 is disposed adjacent to the motor housing 404. Next, the pressure sensor 438 and the sensor cable 448 are coupled to the collar 434 such that the sensor 438 is disposed within the internal chamber 436 of the collar 434 and the sensor cable 448 extends from the proximally-directed opening 449. Next, the collar 434 and the pressure sensor 438 within the collar 434 are advanced distally along the catheter 426. Next, the collar 434 can be coupled to the catheter 426 by forming an outer jacket (not shown) that at least partially surrounds the collar 434 and the catheter 426, crimping the collar 434, applying one or more adhesives, and / or forming one or more welds (not shown).

[0056] Without departing from the scope of the present invention, various modifications and additions can be made to the illustrated exemplary embodiments described. For example, although the above-described embodiments refer to specific features, the scope of the present invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to embrace all such alternative, modified, and variant forms included within the claims of the patent, together with all of their equivalents.

Claims

1. A percutaneous circulatory assist device, a housing, an impeller disposed within the housing and configured to rotate relative to the housing to allow blood to flow through the housing, a motor operably coupled to the impeller and configured to rotate the impeller relative to the housing, a catheter coupled to the motor, a collar coupled to the catheter and disposed proximally relative to the housing, the collar including an internal chamber, and a pressure sensor disposed within the internal chamber of the collar. A percutaneous circulatory assist device comprising the above.

2. The percutaneous circulatory assist device according to claim 1, wherein the collar further includes an opening coupled to the internal chamber.

3. The percutaneous circulatory assist device according to claim 2, wherein the opening is a distally facing opening.

4. The percutaneous circulatory assist device according to claim 2 or 3, wherein the collar further includes an outer surface, and the outer surface includes a tapered distal portion forming the opening.

5. The percutaneous circulatory assist device according to claim 4, wherein the outer surface further includes a tapered proximal portion.

6. The percutaneous circulatory assist device according to claim 5, wherein the tapered distal portion has a first inclination, the tapered proximal portion has a second inclination, and the first inclination is greater than the second inclination.

7. The percutaneous circulatory assist device according to claim 5 or 6, wherein the outer surface further includes a cylindrical surface between the tapered distal portion and the tapered proximal portion.

8. The percutaneous circulatory assist device according to claim 2, wherein the opening is a laterally facing opening.

9. The percutaneous circulatory assist device according to claim 8, wherein the collar further includes a distally facing opening coupled to the internal chamber.

10. The percutaneous circulatory assist device according to claim 8 or 9, wherein the laterally facing opening is a first laterally facing opening, and the collar further includes a second laterally facing opening coupled to the internal chamber.

11. The percutaneous circulatory assist device according to claim 2, wherein the opening extends at an acute angle with respect to the longitudinal axis of the internal chamber.

12. The percutaneous circulatory assist device according to any one of claims 1 to 11, further comprising a sensor mount disposed within the internal chamber of the color and coupled to the pressure sensor.

13. A percutaneous circulatory assist device, a housing, an impeller disposed within the housing, the impeller configured to rotate relative to the housing to allow blood to flow through the housing, a motor operably coupled to the impeller, the motor configured to rotate the impeller relative to the housing, a catheter coupled to the motor, a collar coupled to the catheter and disposed proximal to the housing, an internal chamber, a distally directed opening coupled to the internal chamber, a proximally directed opening coupled to the internal chamber, the collar including the proximally directed opening, a pressure sensor disposed within the internal chamber of the collar, a sensor cable coupled to the pressure sensor, the sensor cable extending through the proximally directed opening, a percutaneous circulatory assist device comprising the sensor cable.

14. The percutaneous circulatory assist device according to claim 13, wherein the pressure sensor includes one of an optical pressure sensor and an electrical pressure sensor.

15. The percutaneous circulatory assist device according to claim 13 or 14, wherein the pressure sensor is disposed at least 0.00254 centimeters (0.001 inches) away from an outer surface of the catheter.

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