Post-implantation tensioning in cardiac implants

Abstract

A method of treating a heart of a patient is provided. The method includes implanting a first tissue anchor in cardiac tissue of the patient and a second tissue anchor in the patient, such that the first and the second tissue anchors are coupled together by one or more tethers. Thereafter, after allowing at least 24 hours for tissue growth on the first tissue anchor to strengthen anchoring of the first tissue anchor in the cardiac tissue, tension is applied between the first and the second tissue anchors using at least a longitudinal portion of the one or more tethers. Other embodiments are also described.

1 . A method of treating a heart of a patient, comprising:
 implanting a first tissue anchor in cardiac tissue of the patient and a second tissue anchor in the patient, such that the first and the second tissue anchors are coupled together by one or more first tethers, wherein the one or more first tethers have a first coupling site at a fixed location along the one or more tethers; and   thereafter, after allowing at least 24 hours for tissue growth on the first tissue anchor to strengthen anchoring of the first tissue anchor in the cardiac tissue:
 coupling a second coupling site along a second tether to the first coupling site along the one or more first tethers, the second coupling site at a fixed location along the second tether; and 
 applying tension between the first and the second tissue anchors using at least a longitudinal portion of the one or more first tethers and the second tether, while the second coupling site remains coupled to the first coupling site. 
   
     
     
         2 . The method according to  claim 1 , wherein the one or more first tethers are slack before applying the tension. 
     
     
         3 . (canceled) 
     
     
         4 . The method according to  claim 1 ,
 wherein the one or more first tethers comprise a first coupler that is fixed to the one or more first tethers at the first coupling site,   wherein the second tether comprises a second coupler that is fixed to the second first tether at the second coupling site, and   wherein coupling the second coupling site of the second tether to the first coupling site comprises coupling the second coupler to the first coupler.   
     
     
         5 . The method according to  claim 4 , wherein the second coupler comprises a hook. 
     
     
         6 . (canceled) 
     
     
         7 . The method according to  claim 1 , wherein the second tissue anchor comprises a stent that comprises a plurality of struts, and wherein coupling the second tether to the second tissue anchor comprises coupling, to one or more of the struts, a second-tissue-anchor coupler that is attached to the second tether. 
     
     
         8 . The method according to  claim 7 , wherein the second-tissue-anchor coupler comprises a hook. 
     
     
         9 . The method according to  claim 7 , wherein the second-tissue-anchor coupler is shaped so as to define an opening. 
     
     
         10 . The method according to  claim 7 , wherein at least one of the struts is oriented axially as a backbone, and wherein coupling the second-tissue-anchor coupler to the one or more of the struts comprises coupling the second-tissue-anchor coupler to the backbone. 
     
     
         11 . The method according to  claim 10 , wherein the backbone is shaped so as to define one or more hooks, and wherein coupling the second-tissue-anchor coupler to the backbone comprises coupling the second-tissue-anchor coupler to one or more of the hooks. 
     
     
         12 - 13 . (canceled) 
     
     
         14 . The method according to  claim 1 , wherein applying the tension comprises applying the tension after allowing at least one week for tissue growth on the first tissue anchor. 
     
     
         15 . The method according to  claim 1 , wherein applying the tension comprises applying the tension within two months after implanting the first tissue anchor. 
     
     
         16 . The method according to  claim 1 , wherein implanting the first tissue anchor comprises implanting the first tissue anchor in a vicinity of a tricuspid valve of the patient. 
     
     
         17 . The method according to  claim 1 , wherein implanting the second tissue anchor comprises implanting the second tissue anchor in a blood vessel selected from the group consisting of: a superior vena cava (SVC), an inferior vena cava (IVC), and a coronary sinus. 
     
     
         18 - 20 . (canceled) 
     
     
         21 . The method according to  claim 1 , wherein the second coupling site is fixed at a distal end of the second tether.