Apparatus and methods are described including a blood pump that includes a catheter, a first impeller disposed on the catheter, and a second impeller disposed on the catheter, proximally to the first impeller. A motor drives the first and second impellers to pump blood of a subject, by driving the first and second impellers to rotate. The blood pumps is configured such that (a) the first and second impellers are shaped differently from each other when the first and second impellers are in non-radially-constrained configurations, (b) the first and second impellers are sized differently from each other when the first and second impellers are in non-radially-constrained configurations, and/or (c) the first and second impellers are driven by the motor to rotate under respective rotation conditions that are different from each other. Other applications are also described.

A system may comprise a first catheter having a first steerable segment and a second catheter disposed within the first catheter. The second catheter may have a second steerable segment. The system may also comprise an imaging element supported at a distal end of the second catheter, a coil reference sensor supported at a distal portion of the second catheter, and a processor in electrical communication with the coil reference sensor. The processor may be configured to determine a position of a distal portion of the first catheter with reference to the coil reference sensor.

Balloon catheters and methods are provided for selectively occluding blood flow into a right atrium of a patient's heart communicating with an inferior vena cava (IVC) and superior vena cava (SVC). In one embodiment, a catheter includes first and second balloons adjacent one another on a distal end of the catheter shaft. During use, the distal end is introduced into the right atrium and positioned such that the first balloon is located within the right atrium. The first balloon is expanded within the right atrium and the catheter shaft directed such that the expanded first balloon engages at least a portion of the IVC to prevent substantial inflow into the right atrium from the IVC. The second balloon is then expanded to limit inflow into the right atrium from the SVC, and a medical procedure is performed within the patient's body.

Interventional procedures on the carotid arteries are performed through a transcervical access while retrograde blood flow is established from the internal carotid artery to a venous or external location. A system for use in accessing and treating a carotid artery includes an arterial access device, a shunt fluidly connected to the arterial access device, and a flow control assembly coupled to the shunt and adapted to regulate blood flow through the shunt between at least a first blood flow state and at least a second blood flow state. The flow control assembly includes one or more components that interact with the blood flow through the shunt.

Apparatus and methods are described including a catheter, a first pump disposed on the catheter, and a second pump disposed on the catheter, proximally to the first pump. A control unit is configured to control activation of the first and second pumps. The first and second pumps are configured, when activated, to pump fluid in opposite directions from one another. Other applications are also described.

Exemplary embodiments of devices and method for affecting at least one anatomical tissue can be provided. A configuration can be provided that includes a structure which is expandable (i) having and/or (ii) forming at least one opening or a working space through which the anatomical tissue(s) is placed in the structure. For example, the structure, prior to being expanding, can have at least one partially rigid portion. In addition, or as an alternative, upon a partial or complete expansion thereof, the structure can be controllable to have a plurality of shapes. Further, the structure can be controllable to provide the working space with multiple shapes and/or multiple sizes.

Electrophysiology mapping and visualization systems are described herein where such devices may be used to visualize tissue regions as well as map the electrophysiological activity of the tissue. Such a system may include a deployment catheter and an attached hood deployable into an expanded configuration. In use, the imaging hood is placed against or adjacent to a region of tissue to be imaged in a body lumen that is normally filled with an opaque bodily fluid such as blood. A translucent or transparent fluid, such as saline, can be pumped into the imaging hood until the fluid displaces any blood, thereby leaving a clear region of tissue to be imaged via an imaging element in the deployment catheter. A position of the catheter and/or hood may be tracked and the hood may also be used to detect the electrophysiological activity of the visualized tissue for mapping.

Described herein are devices and related methods for occluding at least a portion of a bodily lumen during a procedure. In some embodiments, the device includes an inner shaft defining a lumen therethrough and a first aperture; and an outer shaft including a flexible member and defining a lumen therethrough and a second aperture positioned proximally on the outer shaft relative to the flexible member. The inner shaft extends through the lumen of the outer shaft, such that at least a portion of the outer shaft is axially translatable toward and away from the distal portion of the inner shaft. The flexible member is movable between an unexpanded configuration and an expanded configuration when at least a portion of the outer shaft is translated axially toward or away from the distal portion of the inner shaft. In some embodiments, the device and methods are used for endoscopy procedures.

Interventional procedures on the carotid arteries are performed through a transcervical access while retrograde blood flow is established from the internal carotid artery to a venous or external location. A system for use in accessing and treating a carotid artery includes an arterial access device, a shunt fluidly connected to the arterial access device, and a flow control assembly coupled to the shunt and adapted to regulate blood flow through the shunt between at least a first blood flow state and at least a second blood flow state. The flow control assembly includes one or more components that interact with the blood flow through the shunt.

A catheter for prevention of stroke by diverting and filtering the blood flow to carotid and vertebral arteries is provided. The catheter includes at least one balloon with an outer mesh cover that expands upon the balloon inflation and collapses upon balloon deflation. Partial inflation of balloons provides for full mesh expansion in the target vessel with resulting capturing and retrieval of embolic particles. The inflation of the balloon in the aortic arch or head vessels expands the balloon associated filtering mesh leading to both filtering and deflection of embolic particles from the cerebral circulation, while balloon deflation triggers the mesh collapse and promotes its recapturing and retrieval while minimizing the risk of spillage of captured emboli.