Apparatus and methods are described including delivering a left-ventricular assist device to a subject's left ventricle. A tube is positioned such that a proximal portion of the tube traverses an aortic valve of the subject, and a distal portion of the tube is disposed within a left ventricle of the subject. A pump pumps blood through the tube from the subject's left ventricle to the subject's aorta such as to cause the proximal portion of the tube to be maintained in an open state, and to cause at least a portion of the tube to become curved. Other applications are also described.

Apparatus and methods are described including delivering a left-ventricular assist device to a subject's left ventricle. A tube is positioned such that a proximal portion of the tube traverses an aortic valve of the subject, and a distal portion of the tube is disposed within a left ventricle of the subject. A pump pumps blood through the tube from the subject's left ventricle to the subject's aorta such as to cause the proximal portion of the tube to be maintained in an open state, and to cause at least a portion of the tube to become curved. Other applications are also described.

Apparatus and methods are described including delivering a left-ventricular assist device to a subject's left ventricle. A tube is positioned such that a proximal portion of the tube traverses an aortic valve of the subject, and a distal portion of the tube is disposed within a left ventricle of the subject. A pump pumps blood through the tube from the subject's left ventricle to the subject's aorta. A curved element is disposed within the tube and is configured to cause at least a portion of the tube to become curved. Other applications are also described.

Apparatus and methods are described including delivering a left-ventricular assist device to a subject's left ventricle. A tube is positioned such that a proximal portion of the tube traverses an aortic valve of the subject, and a distal portion of the tube is disposed within a left ventricle of the subject. A pump pumps blood through the tube from the subject's left ventricle to the subject's aorta. A curved element is disposed within the tube and is configured to cause at least a portion of the tube to become curved. Other applications are also described.

Apparatus and methods are described including an impeller (50) that includes a proximal bushing (64) and a distal bushing (58). Two or more helical elongate elements (52) extend from the proximal bushing (64) to the distal bushing (58), and an axial structure (54) is disposed inside of the two or more helical elongate elements (52), and along an axis around which the helical elongate elements (52) wind. The impeller (50) includes an impeller-overexpansion-prevention element (72). The impeller-overexpansion-prevention element is a single integrated structure that includes a ring (73) disposed around the axial structure (54), and a plurality of elongate elements (67) each of the elongate elements (67) extending from the ring to a respective helical elongate element (52) and being coupled to the respective helical elongate element (52) so as to prevent radial expansion of the impeller (50). Other applications are also described.

Systems and methods are provided herein for estimating a position of a heart pump system in a patient. The system receives first data indicative of a time-varying motor current during a first time period. The motor current corresponds to an amount of current delivered to a motor, while the heart pump system is operating in the patient. The system receives second data indicative of a time-varying differential pressure during the first time period. The differential pressure is indicative of a position of the heart pump system relative to patient's heart. The system receives third data indicative of time-varying motor current during a second time period, and determines an estimate of differential pressure during the second period of time from the third data and a relationship between the first data and the second data. The estimate is usable to predict the position of the heart pump system in the patient.

Systems and methods are provided herein for estimating a position of a heart pump system in a patient. The system receives first data indicative of a time-varying motor current during a first time period. The motor current corresponds to an amount of current delivered to a motor, while the heart pump system is operating in the patient. The system receives second data indicative of a time-varying differential pressure during the first time period. The differential pressure is indicative of a position of the heart pump system relative to patient's heart. The system receives third data indicative of time-varying motor current during a second time period, and determines an estimate of differential pressure during the second period of time from the third data and a relationship between the first data and the second data. The estimate is usable to predict the position of the heart pump system in the patient.

Apparatus and methods are described including a left-ventricular assist device that includes a tube configured to traverse a subject's aortic valve, with a distal portion of the tube within the subject's left ventricle. A frame disposed within the distal portion of the tube defines cells, and a width of each of the cells within a generally cylindrical portion of the frame is less than 2 mm. An inner lining lines at least some of the cylindrical portion of the frame. An impeller is disposed inside the frame. Other applications are also described.

Apparatus and methods are described including a left-ventricular assist device that includes a tube configured to traverse a subject's aortic valve, with a distal portion of the tube within the subject's left ventricle. A frame disposed within the distal portion of the tube defines cells, and a width of each of the cells within a generally cylindrical portion of the frame is less than 2 mm. An inner lining lines at least some of the cylindrical portion of the frame. An impeller is disposed inside the frame. Other applications are also described.

Apparatus and methods are described including a ventricular assist device that includes a frame having struts that define a plurality of cells. In its non-radially-constrained configuration, the frame includes a generally cylindrical portion. A tube defines blood outlet openings, and a portion of the tube is disposed outside the frame and is coupled to the generally cylindrical portion of the frame, such that the portion of the tube conforms with a structure of struts of the frame. An inner lining is coupled to an inside of the generally cylindrical portion of the frame, such as to provide the generally cylindrical portion of the frame with a smooth inner surface. An impeller is disposed at least partially inside the generally cylindrical portion of the frame and is configured to pump blood through the tube and out of the one of more blood outlet openings. Other applications are also described.