Conduit designs and related methods for optimal flow control

Abstract

A bypass conduit and related methods include implanting a bypass in the heart between a heart chamber and an at least partially occluded artery to directly flow blood from the chamber to the artery. The bypass conduit is configured to have a higher resistance to blood flow in a first direction than in a second direction without any active flow control mechanism. The bypass conduit may have a first end defining a first opening and a second end defining a second opening and a wall extending between the two ends that defines a lumen extending between the two openings. The ends and the wall of the conduit are configured to have a higher resistance to blood flow in a first direction than in a second direction. A method of bypassing an at least partially occluded artery includes determining a resistance to blood flow of the artery at a location of an at least partial occlusion and selecting a conduit having a configuration based on the resistance to blood flow of the artery at the location of the at least partial occlusion. The method further includes implanting the conduit in a heart wall between the heart chamber and the artery downstream of the at least partial occlusion to directly flow blood between the chamber and the artery.

What is claimed is:  
     
         1 . A bypass conduit for implantation in a heart to bypass an at least partially occluded artery, comprising: 
 a first end defining a first opening;    a second end opposite the first end and defining a second opening; and    a wall extending between the first and second ends defining a lumen extending between the first and second openings, wherein said ends and said wall are configured such that the conduit has a greater resistance to blood flow in a first direction than in a second direction.    
     
     
         2 . The bypass conduit of  claim 1 , wherein the conduit is configured to be implanted in a heart wall with the first opening configured to be in flow communication with the left ventricle and the second opening configured to be in flow communication with the artery at a location downstream from the occlusion.  
     
     
         3 . The bypass conduit of  claim 2 , wherein the ratio of the resistance to blood flow through the conduit from the artery to the left ventricle to a resistance to blood flow through the conduit from the left ventricle to the artery is greater than approximately 1.1.  
     
     
         4 . The bypass conduit of  claim 2 , wherein a ratio of a resistance to blood flow conduit from the artery to the left ventricle to a resistance to blood flow through the conduit from the left ventricle to the artery is approximately 2.  
     
     
         5 . The bypass conduit of  claim 1 , wherein the artery has a resistance to blood flow of at least approximately 45 mmHg sec/ml to approximately 76 mmHg sec/ml at a location of an occlusion.  
     
     
         6 . A method of bypassing an at least partially occluded artery, comprising: 
 determining a resistance to blood flow of the artery at a location of an at least partial occlusion;    selecting a conduit having a configuration based on the resistance to blood flow of the artery at the location of the at least partial occlusion; and    implanting the conduit in a heart wall between a heart chamber and the artery downstream of the at least partial occlusion to directly flow blood between the chamber and the artery.    
     
     
         7 . The method of  claim 6 , wherein the selecting includes selecting a conduit having a higher resistance to blood flow in a direction from the artery to the chamber than in a direction from the chamber to the artery when the resistance to blood flow of the artery at the location of the at least partial occlusion ranges from approximately 45 mmHg sec/ml to 76 mmHg sec/ml.  
     
     
         8 . A bypass conduit for implantation in a heart to bypass an at least partially occluded artery, comprising: 
 a first end defining a first opening;    a second end opposite the first end defining a second opening; and    a wall extending between the first and second ends defining a lumen extending between the first and second openings, wherein said conduit is configured to have a greater resistance to blood flow in a first direction than in a second direction without any active flow control mechanism.