In one embodiment of the present invention, a cannula for use with a blood circulation device may include the cannula having a longitudinal axis and proximal and distal directions along the longitudinal axis. The cannula may also include a proximal portion having a wall extending around the longitudinal axis and having outer and inner faces, the inner face may define a bore, the proximal portion may have dimensions transverse to the longitudinal axis, and the dimensions may be constant in the proximal and distal directions. Also, the cannula may have a distal portion having an outer face, continuous with the outer face of the proximal portion. The outer face of the distal portion may extend around and along the longitudinal axis, and the outer face of the distal portion may taper distally toward the longitudinal axis. The distal portion may include at least two openings extending from the outer face of the distal portion, which may merge with one another within the distal portion. Then, the openings may communicate with the bore of the proximal portion. One type of blood circulation device may be a ventricular assist device.
