Oval-Shaped Cardiac Cannula

Abstract

A method of performing minimally invasive cardiac surgery includes the step of creating an access aperture into a patient's chest cavity, the access aperture being considerably smaller than a traditional cardiac surgery incision. A cannula is provided that has an oval portion with a longer major axis and a shorter minor axis and the cannula is inserted into the chest cavity through the access aperture.

1 - 83 . (canceled)  
   
   
       84 . A cannula for use in conducting fluid to or from a body, comprising: a cannula body having a proximal end, a distal end, and a lumen extending between the proximal and distal ends; a first fluid aperture formed on the proximal end; a second fluid aperture formed adjacent the distal end; and a reinforcement integrally provided in the cannula body; wherein a cross section of a first portion of the cannula body is non-circular and has a major cross-sectional axis and a minor cross-sectional axis, the length of the major axis being greater than the length of the minor axis and wherein the lumen extending through the first portion of the cannula body has a substantially similar cross-sectional shape as the cross section of the first portion of the cannula body.  
   
   
       85 . The cannula of  claim 84 , further comprising a third fluid aperture formed proximally a spaced distance from the second fluid aperture.  
   
   
       86 . The cannula of  claim 84 , wherein the cross section of the first portion of the cannula body is oval.  
   
   
       87 . The cannula of  claim 84 , wherein the proximal end and the distal end of the cannula body have a circular cross section and the first portion is disposed between the proximal and distal ends.  
   
   
       88 . A cannula for use in conducting fluid to or from a body, comprising: a cannula body having a proximal end and a distal end, the cannula body having an outer surface; a lumen extending between the proximal and distal ends, the lumen defined by an inner surface of the cannula body; a first fluid aperture formed on the proximal end; and a second fluid aperture formed adjacent the distal end; wherein a first portion of the cannula body has a cross section of the outer surface that is non-circular and a cross section of the inner surface that is the same shape as the cross section of the outer surface.  
   
   
       89 . The cannula of  claim 88 , further comprising a third fluid aperture formed proximally a spaced distance from the second fluid aperture.  
   
   
       90 . The cannula of  claim 88 , wherein the cross section of the outer surface of the first portion of the cannula body is oval.  
   
   
       91 . The cannula of  claim 88 , further comprising a reinforcement integrally provided in the cannula body.  
   
   
       92 . The cannula of  claim 88 , wherein a cross section of the outer surface of the cannula body at the proximal end and at the distal end is circular and the first portion is disposed between the proximal and distal ends.  
   
   
       93 . A cannula for use in conducting fluid to or from a body, comprising: a cannula body having a proximal end with a circular cross section, a distal end with a circular cross section, and a lumen extending between the proximal and distal ends; a first fluid aperture formed on the proximal end; and a second fluid aperture formed adjacent the distal end; wherein a cross section of a first portion of the cannula body between the proximal end and the distal end is oval.  
   
   
       94 . The cannula of  claim 93 , further comprising a third fluid aperture formed proximally a spaced distance from the second fluid aperture.  
   
   
       95 . The cannula of  claim 93 , wherein the lumen extending through the first portion of the cannula body has an oval cross-sectional shape.  
   
   
       96 . The cannula of  claim 93 , further comprising a reinforcement integrally provided in the cannula body.  
   
   
       97 . The cannula of  claim 84 , wherein the reinforcement is a helical reinforcing spring.  
   
   
       98 . The cannula of  claim 91 , wherein the reinforcement is a helical reinforcing spring.  
   
   
       99 . The cannula of  claim 96 , wherein the reinforcement is a helical reinforcing spring.