Apparatus is described including a blood-pump tube (24), and a blood pump (50) disposed within the blood-pump tube (24), and configured to pump blood through the blood-pump tube (24). At least one blood-pressure-measurement tube (210, 220, 222) defines an opening (214) at a distal end thereof, and is configured to extend to at least an outer surface of the blood-pump tube (24), such that the opening (214) at the distal end of the blood-pressure-measurement tube (210, 220, 222) is in direct fluid communication with a bloodstream of the subject outside the blood-pump tube (24). At least one pressure sensor (216) measures pressure of the bloodstream of the subject outside the blood-pump tube (210, 220, 222) by measuring pressure of blood within the blood-pressure-measurement tube (210, 220, 222). Other applications are also described.
