CIRCULATORY SUPPORT SYSTEM

An example cardiac pump system includes a catheter shaft having a proximal end region coupled to a handle and a distal end region coupled to a cardiac pump, wherein the cardiac pump includes an impeller housing, a cannula and an impeller, wherein the cannula includes a distal end region and a proximal end region, wherein the distal end region of the cannula is configured to be positioned in a left ventricle of a heart. Further, the cardiac pump system includes a first flow sensor coupled to the cannula or the catheter shaft, wherein the first flow sensor is configured to directly sense a first velocity of blood flowing adjacent to the first flow sensor.

TECHNICAL FIELD

The present disclosure relates to percutaneous circulatory support device systems. More specifically, the disclosure relates to percutaneous circulatory support devices that include one or more flow sensors.

BACKGROUND

Percutaneous circulatory support devices such as blood pumps can provide transient cardiac support in patients whose heart function or cardiac output is compromised. Such devices may be delivered percutaneously from the femoral artery, retrograde through the descending aorta, over the aortic arch, through the ascending aorta across the aortic valve, and into the left ventricle. Some percutaneous circulatory support devices may include one or more flow sensors positioned thereon for directly measuring the flow of blood adjacent thereto. The direct measurement of blood flow may help derive the position of the support device within the heart, the cardiac output of the heart or other cardiac parameters. Accordingly, there is an ongoing need to provide circulatory support device systems including one or more flow sensors designed to provide cardiac information and/or other data related to a cardiac procedure. Circulatory support device systems including one or more flow sensors designed to provide cardiac information and/or other data related to a cardiac procedure are disclosed herein.

SUMMARY

This disclosure provides design, material, manufacturing method, and use alternatives for medical devices and/or systems. An example cardiac pump system includes a catheter shaft having a proximal end region coupled to a handle and a distal end region coupled to a cardiac pump, wherein the cardiac pump includes an impeller housing, a cannula and an impeller, wherein the cannula includes a distal end region and a proximal end region, wherein the distal end region of the cannula is configured to be positioned in a left ventricle of a heart. Further, the cardiac pump system includes a first flow sensor coupled to the cannula or the catheter shaft, wherein the first flow sensor is configured to directly sense a first velocity of blood flowing adjacent to the first flow sensor.

Alternatively or additionally to any of the embodiments above, further comprising a console coupled to the handle, wherein the console includes a processor, and wherein the console is configured to receive a first signal from the first flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the first signal corresponds to the first velocity of blood sensed by the first flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the processor is configured to calculate a cardiac output of the heart based on the first velocity of blood sensed by the first flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is attached to an outer surface of the distal end region of the cannula.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is embedded within a wall of the cannula.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is coupled to the cannula, and wherein the cardiac pump system further includes a second flow sensor coupled to the catheter shaft.

Alternatively or additionally to any of the embodiments above, wherein the second flow sensor is configured to directly sense a second velocity of blood flowing adjacent to the second flow sensor, and wherein the console is configured to receive a second signal from the second flow sensor, and wherein the second signal corresponds to the second velocity of blood flowing adjacent to the second flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the processor is configured to compare the first velocity of blood sensed by the first flow sensor to the second velocity of blood sensed by the second flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the processor is configured to calculate a position of the cardiac pump based on a comparison of the first velocity of blood sensed by the first flow sensor to the second velocity of blood sensed by the second flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is positioned along the catheter shaft such that it is positioned distal of a subclavian artery when the distal end region of the cannula is positioned in the left ventricle.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is positioned along the catheter shaft such that it is positioned proximal of a subclavian artery when the distal end region of the cannula is positioned in the left ventricle.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is positioned along the catheter shaft such that it is positioned adjacent to and distal of a renal artery when the distal end region of the cannula is positioned in the left ventricle.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is positioned along the catheter shaft such that it is positioned adjacent to and proximal of a renal artery when the distal end region of the cannula is positioned in the left ventricle.

Another example cardiac pump system includes a console including a processor and a cardiac pump device including a handle coupled to the console, a first catheter shaft having a proximal end region coupled to the handle and a distal end region coupled to a cardiac pump, an impeller and a cannula, wherein the cannula includes a proximal end region and a distal end region. Further, the cardiac pump system also includes a first flow sensor coupled to the proximal end region of the cannula, wherein the first flow sensor is positioned between the impeller and the distal end region of the cannula.

Alternatively or additionally to any of the embodiments above, wherein the first flow sensor is configured to directly sense a first velocity of blood flowing adjacent to the first flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the processor is configured to calculate a cardiac output of the heart based on the first velocity of blood sensed by the first flow sensor.

Alternatively or additionally to any of the embodiments above, wherein the cardiac pump device further includes one or more blood inlets positioned on the distal end region of the cannula, and wherein the one or more blood inlets are configured to be positioned in a left ventricle of a heart.

Alternatively or additionally to any of the embodiments above, further comprising a second flow sensor coupled to the catheter shaft.

Another example method for positioning a cardiac pump system in a heart includes advancing a cardiac pump device adjacent to a left ventricle of the heart, the cardiac pump device including an impeller, a cannula including a proximal end region and a distal end region, and a first flow sensor coupled to the proximal end region of the cannula, wherein the first flow sensor is positioned between the impeller and the distal end region of the cannula. The method also includes positioning the distal end region of the cannula in the left ventricle and positioning the impeller in the ascending aorta of the heart.

DETAILED DESCRIPTION

FIG.1illustrates an example percutaneous circulatory system10including a circulatory support device12positioned in the heart14of a patient16. The circulatory support device12may include a flexible elongated catheter shaft20having a first end attached to a handle22and a second end attached to a blood pump24.FIG.1illustrates the blood pump24positioned in the left ventricle18of the patient16. The blood pump24may be delivered (e.g., tracked) to the ventricle18percutaneously over a guidewire. For example, the catheter shaft20and blood pump24may be tracked over a guidewire through the femoral artery, past the renal arteries60and the descending aorta, over the aortic arch, through the ascending aorta37, past the aortic valve and into the left ventricle18.

FIG.1further illustrates that the handle22may include a distal end region attached to the catheter shaft20and a proximal end region attached to an electrical power cable26. The electrical power cable26may include a distal end region connected to a console28. It can be appreciated that the handle22may include one or more actuators (e.g., buttons, levers, dials, switches, etc.) designed to permit a clinician to control various functions of the blood pump24. For example, a clinician may be able to control the speed of the motor and/or an impeller located in the blood pump24via actuation of one or more actuators located on the handle22.

Additionally,FIG.1illustrates that the console28may include one or more control knobs (e.g., buttons, knobs, dials, etc.)30and/or one or more displays. For example,FIG.1illustrates the console28may include a first display32and a second display34. It can be appreciated that the console28may include more than two displays. Additionally, whileFIG.1illustrates the first display32and the second display34integrated into the console28, it is contemplated that the circulatory system10may be designed such that the first display32, the second display34or both the first display32and the second display34are separate, distinct components of the circulatory system10. In other words, the first display32, the second display34or both the first display32and the second display34may be separate stand-alone displays, apart from the console28. In some examples, the first display32and the second display34may get their respective data from separate sources.

In some examples, the second display34may be designed to attach to the console28and/or the first display32. For example, the first display32may be integrated into the console28while the second display34may be configured to attach to portion of the console28. In yet other examples, both the first display32and the second display34may be a separate stand-alone display whereby the second display34may be configured to attach to the first display32, or wherein the first display32may be configured to attach to the second display34.

FIG.2illustrates that the console28may include, among other suitable components, one or more processors36, memory38, and an I/O unit40. The processor36of the console28may include a single processor or more than one processor (e.g., a first processor36providing data/instructions to the first display32and a second processor36providing data instructions to a second display34) working individually or with one another. The processor36may be configured to execute instructions, including instructions that may be loaded into the memory38and/or other suitable memory. Example processor components may include, but are not limited to, microprocessors, microcontrollers, multi-core processors, graphical processing units, digital signal processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), discrete circuitry, and/or other suitable types of data processing devices. In some examples, the processor36of the console may be configured to execute program instructions. Program instructions may include, for example, firmware, microcode or application code that is executed by the processor36, a microprocessor and/or microcontroller. The one or more processors36may be configured to each manage different functions. They may also be configured to concurrently perform the same functions (e.g., redundant system). Further yet, they may be configured such that a first processor36performs a given function and second processor36checks the result of the function of the first processor36for correctness (e.g., command-monitor system).

In some examples, the first display32may be controlled primarily by the console's firmware control instructions and, therefore, may require relatively little processing power, relatively few instructions and very simple communication between the processor36and the display32, compared to the second display34(e.g., a touch screen display34), which may be controlled primarily by an embedded computer with a flexible and relatively complex communication protocol.

The memory38of the console28may include a single memory component or more than one memory component each working individually or with one another. Example types of memory may include random access memory (RAM), EEPROM, FLASH, suitable volatile storage devices, suitable non-volatile storage devices, persistent memory (e.g., read only memory (ROM), hard drive, Flash memory, optical disc memory, and/or other suitable persistent memory) and/or other suitable types of memory. The memory38may be or may include a non-transitory computer readable medium.

The I/O units40of the console28may include a single I/O component or more than one I/O component each working individually or with one another. Example I/O units40may be any type of communication port configured to communicate with other components of the circulatory system10. Example types of I/O units45may include wired ports, wireless ports, radio frequency (RF) ports, Low-Energy Bluetooth ports, Bluetooth ports, Near-Field Communication (NFC) ports, HDMI ports, Wi-Fi ports, Ethernet ports, VGA ports, serial ports, parallel ports, component video ports, S-video ports, composite audio/video ports, DVI ports, USB ports, optical ports, and/or other suitable ports.

FIG.3illustrates the blood pump24of the percutaneous circulatory system10extending from the ascending aorta37to the left ventricle18of a patient16. The blood pump24may include a cannula44having a proximal end attached to a distal end of an impeller housing46. A proximal end42of the impeller housing46may be attached to a distal end of the catheter shaft20.FIG.3illustrates that, in some examples, the blood pump24may be positioned within the heart14such that the cannula44passes through the aortic valve39, whereby a distal end region41of the cannula44may be positioned within the left ventricle18. As discussed herein, the blood pump24may be tracked over a guidewire to its position illustrated inFIG.3.

FIG.3further illustrates that the shaft20of the circulatory support device12may include one or more blood inlets58located on a distal end region41of the cannula44, and one or more blood outlets48positioned along the impeller housing46. In some examples, the blood pump24may be positioned within the heart14such that the one or more blood inlets58positioned along the distal end region41of the cannula44may be positioned in the left ventricle18and the one or more blood outlets48located along the impeller housing46may be positioned in the ascending aorta37.

Additionally, the blood pump24may include an electrically powered motor that drives rotation of the impeller33which may be positioned within the impeller housing46. In some examples, the motor may power the rotation of the impeller33via electromagnetic induction. The spinning impeller33may draw blood from the left ventricle18(via the one or more blood inlets58located on a distal region of the cannula44) into the ascending aorta37(via the one or more blood outlets48located along the impeller housing46). In other words, an electrically powered motor drives the impeller33to pump blood from the left ventricle18through the aortic valve39and into the ascending aorta37.

Additionally, the circulatory support device12may include one or more sensors coupled to the cannula44, the impeller housing46and/or the catheter shaft20. The one or more sensors coupled to the cannula44, the impeller housing46and/or the catheter shaft20may be designed to monitor blood pressures (e.g., arterial pressure, venous pressure), blood velocity, or other relevant cardiac parameters. Additionally, the one or more sensors of the circulatory support device12coupled to the cannula44, the impeller housing46and/or the catheter shaft20may be designed to monitor other parameters of the circulatory system10, the circulatory support device12and/or the patient16.

FIG.3illustrates that, in some examples, the percutaneous circulatory system10may include a sensor50(e.g., flow sensor, position sensor, etc.) positioned along a distal end region of the cannula44. For example, in which the sensor50is a flow sensor, the flow sensor50may be designed to sense the flowrate of blood (e.g., blood velocity) adjacent to the flow sensor50. For example, the flow sensor50may be designed to directly measure the velocity of blood passing from the left ventricle18, through the aortic valve39and into the ascending aorta37. Any of the example flow sensors described herein may include an optical sensor, ultrasound sensor, electromagnetic sensor, thermoconvection sensor, etc. Additionally, for examples in which the sensor50is a position sensor, the sensor50may be able to determine the positione of the blood pump24relative to the left ventricle18and/or the aorta37based on a sensed measurement of the blood velocity passing adjacent to the sensor50.

FIG.3further illustrates that, in some examples, the percutaneous circulatory system10may include a flow sensor52positioned along a distal end region of the catheter shaft20. In some examples, the flow sensor52may be positioned superior to the subclavian arteries35. In other examples, the flow sensor52may be positioned inferior to the subclavian arteries35. In yet other examples, the flow sensor52may be positioned about 1 cm to 10 cm from the proximal end of the impeller housing46, or about 2 cm to 9 cm from the proximal end of the impeller housing46, about 3 cm to 7 cm from the proximal end of the impeller housing46, or about 4 cm to 6 cm from the proximal end of the impeller housing46, or about 5 cm from the proximal end of the impeller housing46. The flow sensor52may be designed to sense the flowrate of blood (e.g., blood velocity) adjacent to the flow sensor52. For example, the flow sensor52may be designed to directly measure the velocity of blood passing from the left ventricle18, through the aortic valve39and into the ascending aorta37. Any of the example flow sensors described herein may include an optical sensor, ultrasound sensor, electromagnetic sensor, thermoconvection sensor, etc.

Additionally, it can be appreciated that, in some examples, the flow sensor52may be positioned within the descending aorta, superior to the celiac trunk, inferior to the celiac trunk, superior to the renal arteries and/or inferior to renal arteries.

In some instances, the position of the blood pump24(including the position of the blood inlets58, the blood outlets48and/or the impeller33) may be determined by comparing a blood velocity measurement taken at the flow sensor50with a blood velocity measurement taken at the flow sensor52. For example, the processing components36of the percutaneous circulatory system10may include an algorithm designed to receive and compare the blood velocity data sent from the flow sensor50with the blood velocity data from the flow sensor52. It can be appreciated that the velocity of blood passing by the flow sensor50may be less than the velocity of blood passing by the flow sensor52because the velocity of blood passing by the flow sensor52may be increased (e.g., assisted) by the impeller33. In other words, the velocity of blood exiting the blood outlets48may be greater than the blood passing by the flow sensor50and the blood entering the blood inlets58. Further, knowing the distance between the flow sensor50and the flow sensor52, the processing components36may be able to calculate the relative position of the impeller housing (positioned between the flow sensor50and the flow sensor52) by comparing the blood velocity measurement taken at the flow sensor50with the blood velocity measurement taken at the flow sensor52.

Additionally, it can be appreciated that, for any of the flow sensors described herein (e.g., flow sensor50, flow sensor52, etc.), the blood velocity directly measured by a given flow sensor (e.g., flow sensor50, flow sensor52, etc.) may be utilized to calculate a measurement of cardiac output. Cardiac output may be defined as the amount of blood pumped per unit of time (e.g., the volumetric flowrate of blood within the body). Cardiac output may be calculated by multiplying the stroke volume (e.g., the volume of blood exiting the left ventricle per stroke) by the heart rate (e.g., the number of strokes of the left ventricle per unit time).

It can be further appreciated that, in some examples, the processing components36of the percutaneous circulatory system10may include an algorithm designed to receive and compare the blood velocity data sent from any of the flow sensors described herein (e.g., flow sensor50, flow sensor52, etc.) and use it to calculate the cardiac output of the heart14. Further, any of the flow sensors described herein (e.g., the flow sensor50and the flow sensor52) may be coupled to and/or incorporate an impedance sensor, whereby the impedance sensor may be utilized to determine (e.g., calculate) the diameter of a body vessel (e.g., the ascending aorta, descending aorta, etc.) adjacent to a flow sensor (e.g., the flow sensor50and the flow sensor52). It can be appreciated that the diameter of a body vessel (e.g., the ascending aorta, descending aorta, etc.) may be utilized by the processing components36to calculate the cardiac output of the heart14.

Further yet, one or more components of the percutaneous circulatory system10may be coupled to an ultrasound system capable of utilizing ultrasound to determine the diameter of a body vessel (e.g., the ascending aorta, descending aorta, etc.) adjacent to a flow sensor (e.g., the flow sensor50and the flow sensor52). The ultrasound system may communicate with the processing components36of the percutaneous circulatory system10. Accordingly, the processing components36of the percutaneous circulatory system10may include an algorithm capable of receiving data from the ultrasound system corresponding to the diameter of a body vessel (e.g., the ascending aorta, descending aorta, etc.) adjacent to a flow sensor (e.g., the flow sensor50and the flow sensor52). Further, the data received from the ultrasound system may be utilized by the processing components36of the percutaneous circulatory system10to calculate the cardiac output of the heart14.

In yet another example, the percutaneous circulatory system10may include a conductance catheter configured to measure the conductance of blood between two equally spaced electrodes positioned on the conductance catheter, whereby the volume of blood may be calculated based on the conductance reading. Further, knowing the volume of blood in a blood vessel at an instance in time may be used to estimate the diameter of the vessel adjacent to the electrodes. Accordingly, the processing components36of the percutaneous circulatory system10may include an algorithm capable of receiving data from the conductance catheter corresponding to the diameter of a body vessel (e.g., the ascending aorta, descending aorta, etc.). Further, the data received from the conductance catheter may be utilized by the processing components36of the percutaneous circulatory system10to calculate the cardiac output of the heart14.

It can be appreciated that any of the flow sensors described herein (e.g., flow sensor50, flow sensor52, etc.) may send signals to the console28and/or the processing components26via a wireless connection (e.g., a Bluetooth connection). In other examples, any of the flow sensors described herein (e.g., flow sensor50, flow sensor52, etc.) may be hardwired to the console28and/or the processing components26.

FIG.4illustrates an example flow sensor (e.g., the flow sensor52) attached to the catheter shaft20of the circulatory support device12.FIG.4illustrates that the flow sensor52may be sized and shaped to permit the blood to flow across the surface area thereof without substantially impeding or disturbing the velocity and/or fluid dynamics of the blood flow. For example,FIG.4illustrates the flow sensor52having a generally rectangular shape and extending along the longitudinal axis of the catheter shaft20. However, it can be appreciated that the sensor52may include any shape, including a circular, ovular, square, triangular, polygonal, star-shaped, or any combinations thereof.

FIG.5illustrates a cross-sectional view taken along line4-4ofFIG.4.FIG.5illustrates that the sensor52may be attached to an outer surface51of the catheter shaft20. For example,FIG.5illustrates that, in some examples, the sensor52may be a separate component from the catheter shaft20, whereby the sensor52is attached (e.g., via adhesive, etc.) directly to the outside of the catheter shaft20.

However,FIG.6illustrates an alternative example in which the example sensor52is embedded within the wall53of the catheter shaft20. In some examples, the sensor52may be positioned within the wall53of the catheter shaft20during an extrusion process of the catheter shaft20. Further, in some examples, the sensor52may include a first surface which is substantially flush with the outer surface51of the catheter shaft. In other examples, the sensor52may be positioned (e.g., embedded) between the inner surface55and the outer surface51of the catheter shaft20.

FIG.7illustrates that, in some examples, more than one sensor may be positioned along the outer surface of the catheter shaft20. For example,FIG.7illustrates three sensors52positioned along the outer surface51of the catheter shaft20. It can be appreciated that the sensors52may be circumferentially spaced equidistant from one another around the outer surface51of the catheter shaft. For example, the sensors52a,52b,52cshown inFIG.7may be circumferentially spaced substantially 180 degrees from one another. It can be further appreciated that the circulatory support device12may include 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more sensors positioned adjacent one another at a given longitudinal location along the blood pump (e.g., the cannula44, the impeller housing46) and/or the catheter shaft20. At a given longitudinal location, the sensors may be circumferentially spaced substantially equidistant from one another or they may not be spaced equidistant from one another. Further, one or more of any of the sensors described herein may be either attached directly to an outer surface of a portion of the blood pump (e.g., the cannula44, the impeller housing46) and/or the catheter shaft20or the one or more of any of the sensors described herein may be embedded within the wall of a portion of the blood pump (e.g., the cannula44, the impeller housing46) and/or the catheter shaft20.

FIG.8illustrates an example in which a component of the circulatory support device12(e.g., the cannula44, the impeller housing46and/or the catheter shaft20) may include one or more features which are designed to space a flow sensor away from the wall of a body vessel54(e.g., the inner wall of the ascending aorta37). For example,FIG.8illustrates the catheter shaft20may include a first spine56apositioned adjacent to the sensor52and a second spine56bpositioned adjacent to the sensor52. It can be appreciated fromFIG.8that the sensor52may be positioned between the first spine56aand the second spine56b. As viewed inFIG.8, the first spine56amay be positioned above the sensor52and the second spine56bmay be positioned below the sensor52.

FIG.9illustrates a cross-sectional view taken along line8-8ofFIG.8.FIG.9illustrates an example in which the catheter shaft20has shifted toward the inner surface55of the body vessel54. For example,FIG.9may resemble a situation during a medical operation in which the catheter shaft20has pushed up against the inner surface of the ascending aorta of the heart.FIG.9further illustrates that the first spine56aand the second spine56bmay contact the inner surface55of the body vessel54, thereby creating a gap57between the flow sensor52and the inner surface55of the body vessel54. It can be appreciated that the gap57may permit blood to flow across the flow sensor52, thereby allowing the flow sensor to directly measure the blood velocity adjacent to the flow sensor52despite the catheter shaft20having been shifted toward the inner surface55of the body vessel54.

It can further be appreciated that a component of the circulatory support device12(e.g., the cannula44, the impeller housing46and/or the catheter shaft20) may include features other than or in addition to the spine56aand/or the spine56bdesigned to create a space or gap between a flow sensor (e.g., the flow sensor50, the flow sensor52, etc.), thereby allowing blood to flow past the sensor52despite the component having been shifted toward the inner surface of a body vessel. For example, a component of the circulatory support device12(e.g., the cannula44, the impeller housing46and/or the catheter shaft20) may include one or more projections, bumps, protrusions, spikes, ridges, rims, steps, etc. positioned adjacent to a flow sensors to space the flow sensor away from an inner surface of the vessel wall.

FIG.10illustrates that the circulatory support device12may include a flow sensor (similar in form and function to any of the flow sensors described herein) positioned adjacent to the renal arteries60. For example,FIG.10illustrates that a flow sensor62may be attached to the catheter shaft20and positioned superior of the renal arteries60.FIG.10illustrates that a flow sensor64may be attached to the catheter shaft20and positioned inferior of the renal arteries60. The flow sensors62,64may be designed and perform similarly to any of the example flow sensors (e.g., sensors50,52) described herein. For example, the flow sensors62,64may be designed to directly measure the velocity of blood passing thereby. Further, the velocity data collected by the sensors62,64may be utilized by the processing components36to calculate the positioned of the circulatory support device12within the body vessel and/or calculate the cardiac output of the heart14, as described herein.

FIG.11illustrates that, in some instances, the percutaneous circulatory system10may further include a flow-sensing component which is designed to track over and along the catheter shaft20. For example,FIG.11illustrates that the percutaneous circulatory system10may include a secondary sensor assembly66which includes a sensor housing68and a flow sensor70positioned along a distal end region thereof. It can be appreciated that the sensor housing68may include a lumen sized to permit the catheter shaft20to pass therethrough. Accordingly, the catheter assembly66(including the sensor housing68and the flow sensor70) may translate (e.g., slide) relative to the catheter shaft20and/or the blood pump24(including the cannula44and the impeller housing46), thereby permitting the flow sensor70to be positioned at position within body vessel (e.g., aorta) relative to the flow sensor50, the flow sensor52(which may or may not be included in the example system shown inFIG.11), the impeller33, the impeller housing46, the cannula44, the blood inlets58, the blood outlets48or any other component of the system10.

In some examples, the catheter assembly66may further include a push-wire67coupled to the catheter shaft68. In some examples, the push-wire67may be attached to an outer surface of the of the sensor housing68. The push-wire67may be designed to aid in the tracking of the sensor housing68over the catheter shaft20. For example, the push-wire67may provide additional strength to the sensor housing68which helps push the sensor housing68along the catheter shaft20to a desired position within the body vessel.

Additionally, it can be appreciated that the flow sensor70may be designed and perform similarly to any of the example flow sensors (e.g., sensors50,52,62,64) described herein. For example, the flow sensor70may be designed to directly measure the velocity of blood passing thereby. Further, the velocity data collected by the sensor70may be utilized by the processing components36to calculate the position of the circulatory support device12within the body vessel and/or calculate the cardiac output of the heart14, as described herein.

FIG.12illustrates that, in some instances, the percutaneous circulatory system10may further include a flow-sensing assembly which is separate from the components of the circulatory support device12. For example,FIG.12illustrates that the percutaneous circulatory system10may include a separate sensing assembly70which includes a sensor housing72and a flow sensor74positioned along a distal end region thereof. It can be appreciated that the sensor housing72may include a lumen sized to permit a guidewire76(separate from a guidewire utilized to position the blood pump24) to pass therethrough. Accordingly, the sensing assembly70(including the sensor housing72and the flow sensor74) may translate (e.g., slide) may be positioned alongside and relative to the guidewire76and/or the blood pump24(including the cannula44and the impeller housing46), thereby permitting the flow sensor74to be positioned at position within body vessel (e.g., aorta) relative to the flow sensor50, the flow sensor52(which may or may not be included in the example system shown inFIG.12), the impeller33, the impeller housing46, the cannula44, the blood inlets58, the blood outlets48or any other component of the system10.

In some examples, the catheter assembly70may further include a push-wire75coupled to the sensor housing72. In some examples, the push-wire75may be attached to an outer surface of the of the sensor housing72. The push-wire75may be designed to aid in the tracking of the sensor housing72over the guidewire76. For example, the push-wire75may provide additional column strength to the sensor housing72which helps push the sensor housing72along the guidewire76to a desired position within the body vessel.

Additionally, it can be appreciated that the flow sensor74may be designed and perform similarly to any of the example flow sensors (e.g., sensors50,52,62,64.70) described herein. For example, the flow sensor74may be designed to directly measure the velocity of blood passing thereby. Further, the velocity data collected by the sensor74may be utilized by the processing components36to calculate the position of the circulatory support device12within the body vessel and/or calculate the cardiac output of the heart14, as described herein.