Patent ID: 8231519

Claim:
A method for implanting a cannula into the heart of a mammal, wherein said method comprises: (a) puncturing the heart or blood vessel of said mammal, (b) inserting a cannula into a chamber of the heart, wherein said cannula comprises a housing having a proximal region, a distal region, and an intermediate region located between said proximal and distal regions, wherein said housing defines a first lumen and a second lumen, wherein said first lumen comprises (a) a proximal end located within said proximal region of said housing and adapted to engage a blood pump and (b) a distal end located within said distal region of said housing and adapted to be positioned within a cardiovascular system, wherein said second lumen comprises (a) a proximal end located within said proximal region of said housing and adapted to engage said blood pump and (b) a distal end located within said intermediate region of said housing and adapted to be positioned within said cardiovascular system, wherein one of said first and second lumens has a generally reniform cross-sectional shape in said intermediate region formed at least by a substantially circular outer arc, a substantially circular inner arc, a first semicircular arc between first ends of the outer and inner arcs, and a second semicircular arc between second ends of the outer and inner arcs, and wherein said distal region is positioned within a blood vessel of said mammal and said intermediate region is positioned within a chamber of the heart of said mammal, and wherein the reniform shape has rounded corners having a radius greater than about ten percent of the radius of the largest circle that can be inscribed within the reniform shape.