Tools for use with moving organs

Abstract

A sensor senses a phase of cyclic activity of a portion of a subject's body. A control unit, in a first cycle of the cyclic activity, moves a portion of a tool, in a given direction, in response to the sensor sensing that the cyclic activity is at a first given phase thereof. The control unit, following the given phase and prior to an occurrence of the given phase in a subsequent cycle, inhibits the tool's movement. The control unit in a second cycle, subsequent to the inhibiting, moves the tool in the given direction, in response to the sensor sensing that the second cycle is at the given phase, without moving the tool in an opposite direction, between (a) moving the tool in the given direction in the first cycle, and (b) moving the tool in the given direction in the second cycle. Other embodiments are also described.

1 . Apparatus for use with a portion of a body of a subject that moves as a result of cyclic activity of a body system of the subject, the apparatus comprising:
 a sensor for sensing a phase of the cyclic activity;   a medical tool configured to perform a function with respect to the portion of the subject's body; and   a control unit configured:
 in a first cycle of the cyclic activity, to move at least a portion of the tool in a given direction, in response to the sensor sensing that the cyclic activity is at a first given phase thereof, 
 following the given phase in the first cycle and prior to an occurrence of the given phase in a subsequent cycle of the cyclic activity, to inhibit the movement of the at least a portion of the tool, and 
 in a second cycle of the cyclic activity, subsequent to the inhibiting of the movement, to move the at least a portion of the tool in the given direction, in response to the sensor sensing that the second cycle of the cyclic activity is at the given phase thereof, 
 without moving the at least a portion of the tool in a direction opposite to the given direction, between (a) moving the at least a portion of the tool in the given direction in the first cycle, and (b) moving the at least a portion of the tool in the given direction in the second cycle. 
   
     
     
         2 . The apparatus according to  claim 1 , wherein the control unit is configured to move a center of the tool by moving the portion of the tool in the given direction. 
     
     
         3 . The apparatus according to  claim 1 , wherein the tool comprises a tool configured to be controlled remotely by a user. 
     
     
         4 . The apparatus according to  claim 1 , wherein the control unit is configured to be reversibly coupled to the tool. 
     
     
         5 . The apparatus according to  claim 1 , wherein the control unit is integrated into the tool. 
     
     
         6 . The apparatus according to  claim 1 , wherein the tool comprises a guidewire configured to be moved within the portion of the subject's body. 
     
     
         7 . The apparatus according to  claim 1 , wherein the tool is configured to penetrate an occlusion of a lumen of the portion of the subject's body by being advanced through the lumen. 
     
     
         8 . The apparatus according to  claim 1 , wherein the tool comprises a valve configured to be implanted within the portion of the subject's body by being expanded within the portion, and wherein the control unit is configured to move at least a portion of the valve in the given direction, by moving the at least the portion of the valve in an expansion-related direction. 
     
     
         9 . The apparatus according to  claim 1 , wherein the tool comprises a septal-closure device configured to be implanted within the portion of the subject's body by being expanded within the portion, and wherein the control unit is configured to move at least a portion of the septal-closure device in the given direction, by moving the at least the portion of the septal-closure device in an expansion-related direction. 
     
     
         10 . The apparatus according to  claim 1 , wherein the cyclic activity includes a respiratory cycle of the subject, and wherein the sensor is configured to sense a phase of the respiratory cycle. 
     
     
         11 . The apparatus according to  claim 10 , wherein the sensor comprises an image processor configured to sense a phase of the subject's respiratory cycle by comparing image frames of a plurality of image frames of the portion of the subject's body to at least one of the image frames of the plurality of image frames. 
     
     
         12 . The apparatus according to  claim 1 , wherein the cyclic activity includes a cardiac cycle of the subject, and wherein the sensor is configured to sense a phase of the cardiac cycle. 
     
     
         13 . The apparatus according to  claim 12 , wherein the sensor comprises a blood pressure sensor. 
     
     
         14 . The apparatus according to  claim 12 , wherein the sensor comprises an image processor configured to sense a phase of the subject's cardiac cycle, by comparing image frames of the plurality of image frames to at least one of the image frames of the plurality of image frames. 
     
     
         15 . The apparatus according to  claim 12 , wherein the sensor comprises an ECG sensor configured to sense a phase of the cardiac cycle by detecting an ECG signal of the subject. 
     
     
         16 . The apparatus according to  claim 1 , wherein the tool comprises a balloon configured to be inflated inside a lumen of the portion of the subject's body, and wherein the control unit is configured to move at least a portion of the balloon in the given direction, by moving a surface of the balloon in an inflation-related direction. 
     
     
         17 . The apparatus according to  claim 16 , wherein the control unit is configured to inflate the balloon continuously for a period of time prior to the first cycle of the cyclic activity. 
     
     
         18 . The apparatus according to  claim 16 , wherein the control unit is configured to inflate the balloon continuously for a period of time subsequent to the second cycle of the cyclic activity. 
     
     
         19 . The apparatus according to  claim 16 , further comprising a stent, wherein the stent is configured to be positioned against a wall of the lumen via the inflation of the balloon. 
     
     
         20 . The apparatus according to  claim 16 , further comprising a valve disposed on the surface of the balloon, wherein the valve is configured to be expanded via the inflation of the balloon. 
     
     
         21 . The apparatus according to  claim 16 , further comprising a valve configured to control flow to the balloon, and wherein the control unit is configured to regulate movement of the surface of the balloon in the inflation-related direction by controlling the valve. 
     
     
         22 . The apparatus according to  claim 16 , further comprising a tube configured to supply fluid to the balloon, wherein the apparatus further comprises one or more squeezing surfaces that are disposed around the tube, and wherein the control unit is configured to inhibit movement of the surface of the balloon in the inflation-related direction by driving a current that causes the squeezing surfaces to squeeze together. 
     
     
         23 . The apparatus according to  claim 16 , wherein the cyclic activity includes a cardiac cycle of the subject, wherein the portion of the subject's body includes a portion of a cardiovascular system of the subject that moves as a result of the subject's cardiac cycle, and wherein the balloon is configured to be inflated inside the portion of the cardiovascular system. 
     
     
         24 . The apparatus according to  claim 23 , wherein the given phase of the cardiac cycle includes end-diastole, and wherein the control unit is configured to move the surface of the balloon in the inflation-related direction in response to the sensor sensing end-diastole. 
     
     
         25 . The apparatus according to  claim 1 , further comprising an instrument configured to be operated by a user, wherein the control unit is configured to move the portion of the tool in the given direction, (a) in response to the sensor sensing that the cyclic activity is at the given phase thereof, and (b) in response to the instrument being operated by the user. 
     
     
         26 . The apparatus according to  claim 25 , wherein the instrument is configured to provide force feedback to the user that is independent of the cyclic activity. 
     
     
         27 . The apparatus according to  claim 25 , wherein the instrument is configured to provide force feedback to the user that is smoothened with respect to the cyclic activity. 
     
     
         28 . The apparatus according to  claim 1 , wherein the tool comprises a tubular structure configured to bypass an occlusion of a blood vessel within the portion of the subject's body. 
     
     
         29 . The apparatus according to  claim 28 , wherein the tubular structure comprises a blood vessel graft. 
     
     
         30 . The apparatus according to  claim 28 , wherein the control unit is configured to move the tubular structure in the given direction by moving a distal end of the structure in a direction from (a) within the blood vessel on a proximal side of the occlusion, to (b) outside the blood vessel. 
     
     
         31 . The apparatus according to  claim 28 , wherein the control unit is configured to move the tubular structure in the given direction by moving a distal end of the structure in a direction from (a) outside the blood vessel, to (b) within the blood vessel on a distal side of the occlusion. 
     
     
         32 . A method for use with a portion of a body of a subject that moves as a result of cyclic activity of a body system of the subject, the method comprising:
 sensing a phase of the cyclic activity;   inserting a medical tool into the portion of the subject's body, the tool being configured to perform a function;   in a first cycle of the cyclic activity, moving at least a portion of the tool in a given direction, in response to sensing that the cyclic activity is at a given phase thereof;   following the given phase in the first cycle and prior to an occurrence of the given phase in a subsequent cycle of the cyclic activity, inhibiting the movement of the at least a portion of the tool; and   in a second cycle of the cyclic activity, subsequent to the inhibiting of the movement, moving the at least a portion of the tool in the given direction, in response to sensing that the cyclic activity is at the given phase thereof,   without moving the at least a portion of the tool in a direction opposite to the given direction between (a) moving the at least a portion of the tool in the given direction in the first cycle and (b) moving the at least a portion of the tool in the given direction in the second cycle.   
     
     
         33 . The method according to  claim 32 , wherein moving the portion of the tool in the given direction comprises moving a center of the tool. 
     
     
         34 . The method according to  claim 32 , wherein the tool includes a guidewire, and wherein moving the portion of the tool comprises moving a portion of the guidewire. 
     
     
         35 . The method according to  claim 32 , wherein moving the portion of the tool in the given direction comprises penetrating an at least partial occlusion of a lumen of the portion of the subject's body. 
     
     
         36 . The method according to  claim 32 , wherein the tool includes a valve configured to be implanted within the portion of the subject's body by being expanded within the portion, and wherein moving the portion of the tool comprises moving at least a portion of the valve in an expansion-related direction. 
     
     
         37 . The method according to  claim 32 , wherein the tool includes a septal-closure device configured to be implanted within the portion of the subject's body by being expanded within the portion, and wherein moving the portion of the tool comprises moving at least a portion of the septal-closure device in an expansion-related direction. 
     
     
         38 . The method according to  claim 32 ,
 wherein the tool includes a tubular structure configured to bypass an occlusion of a blood vessel within the portion of the subject's body, and   wherein moving the portion of the tool in the given direction comprises moving a distal end of the structure in a direction from (a) within the blood vessel on a proximal side of the occlusion, to (b) outside the blood vessel.   
     
     
         39 . The method according to  claim 32 ,
 wherein the tool includes a tubular structure configured to bypass an occlusion of a blood vessel within the portion of the subject's body, and   wherein moving the portion of the tool in the given direction comprises moving a distal end of the structure in a direction from (a) outside the blood vessel, to (b) within the blood vessel on a distal side of the occlusion.   
     
     
         40 . The method according to  claim 32 , wherein the cyclic activity includes a respiratory cycle of the subject, and wherein sensing the phase comprises sensing a phase of the respiratory cycle. 
     
     
         41 . The method according to  claim 40 , wherein sensing the phase comprises comparing a plurality of image frames of the portion of the subject's body to at least one of the image frames of the plurality of image frames. 
     
     
         42 . The method according to  claim 32 , wherein the cyclic activity includes a cardiac cycle of the subject, and wherein sensing the phase comprises sensing a phase of the cardiac cycle. 
     
     
         43 . The method according to  claim 42 , wherein sensing the phase comprises comparing a plurality of image frames of the portion of the subject's body to at least one of the image frames of the plurality of image frames. 
     
     
         44 . The method according to  claim 32 , wherein the tool includes a balloon configured to be inflated inside a lumen of the portion of the subject's body, and wherein moving the portion of the balloon in the given direction comprises moving a portion of a surface of the balloon in an inflation-related direction by inflating the balloon. 
     
     
         45 . The method according to  claim 44 , further comprising inflating the balloon continuously for a period of time prior to the first cycle of the cyclic activity. 
     
     
         46 . The method according to  claim 44 , further comprising inflating the balloon continuously for a period of time subsequent to the second cycle of the cyclic activity. 
     
     
         47 . The method according to  claim 44 , wherein inflating the balloon comprises positioning a stent against a wall of the lumen. 
     
     
         48 . The method according to  claim 44 , wherein inflating the balloon comprises expanding a valve that is disposed on the surface of the balloon. 
     
     
         49 . The method according to  claim 44 ,
 wherein moving at least the portion of the tool comprises controlling a valve, and   wherein inhibiting the movement of the portion of the tool comprises controlling the valve.   
     
     
         50 . The method according to  claim 44 ,
 wherein inhibiting the movement of the portion of the tool comprises squeezing a tube that supplies fluid to the balloon, and   wherein moving at least the portion of the tool comprises inhibiting the squeezing of the tube.   
     
     
         51 . The method according to  claim 44 ,
 wherein the cyclic activity includes a cardiac cycle of the subject,   wherein the portion of the subject's body includes a portion of a cardiovascular system of the subject that moves as a result of the subject's cardiac cycle, and   wherein moving the portion of the surface of the balloon comprises moving the surface of the balloon inside the portion of the cardiovascular system.   
     
     
         52 . The method according to  claim 51 , wherein the given phase of the cardiac cycle includes end-diastole, and wherein moving the portion of the surface of the balloon in the inflation-related direction comprises moving the portion of the surface of the balloon in response to sensing end-diastole. 
     
     
         53 . The method according to  claim 32 , wherein moving the portion of the tool comprises moving the portion of the tool in response to (a) sensing that the cyclic activity is at the given phase thereof, and (b) an instrument being operated by a user. 
     
     
         54 . The method according to  claim 53 , further comprising providing force feedback to the user that is independent of the cyclic activity. 
     
     
         55 . The method according to  claim 53 , further comprising providing force feedback to the user that is smoothened with respect to the cyclic activity. 
     
     
         56 . Apparatus for use with a portion of a body of a subject that moves as a result of cyclic activity of a body system of the subject, the apparatus comprising:
 a sensor for sensing a phase of the cyclic activity;   a medical tool configured to mechanically perform an action during a single cycle of the cyclic activity with respect to the portion of the subject's body; and   a control unit configured to actuate the tool to mechanically perform the action in response to the sensor sensing that the cyclic activity is at a given phase thereof.   
     
     
         57 . The apparatus according to  claim 56 , wherein the tool comprises a balloon configured to apposition itself to a lumen of the portion of the subject's body during the single cycle by being inflated in response to the sensor sensing that the cyclic activity is at the given phase thereof. 
     
     
         58 . The apparatus according to  claim 57 , wherein the balloon is configured to be inflated continuously for a period of time prior to the balloon appositioning itself to the lumen by being inflated during the single cycle. 
     
     
         59 . The apparatus according to  claim 57 , wherein the balloon is configured to be inflated continuously for a period of time subsequent to the balloon appositioning itself to the lumen by being inflated during the single cycle. 
     
     
         60 . The apparatus according to  claim 56 , wherein the tool comprises a stent configured to apposition itself to a lumen of the portion of the subject's body by being expanded inside the lumen of the portion of the subject's body during a single cycle of the cyclic activity, in response to the sensor sensing that the cyclic activity is at the given phase thereof. 
     
     
         61 . The apparatus according to  claim 60 , wherein the stent comprises a self-expansible portion configured to self-expand inside the lumen of the portion of the subject's body. 
     
     
         62 . The apparatus according to  claim 56 , wherein the tool comprises a valve configured to be implanted within the portion of the subject's body by mechanically expanding within the portion, and wherein the control unit is configured to actuate the valve to expand in response to the sensor sensing that the cyclic activity is at the given phase thereof. 
     
     
         63 . The apparatus according to  claim 62 , wherein the cyclic activity includes a cardiac cycle of the subject, and wherein the control unit is configured to actuate the valve to expand in response to the sensor sensing that the cardiac cycle is at the given phase thereof. 
     
     
         64 . The apparatus according to  claim 63 , wherein the given phase includes an end-diastolic phase of the cardiac cycle, and wherein the control unit is configured to actuate the valve to expand in response to the sensor sensing the end-diastolic phase of the cardiac cycle. 
     
     
         65 . The apparatus according to  claim 56 , wherein the tool comprises a septal-closure device configured to be implanted within a heart of the subject by mechanically expanding within the heart, and wherein the control unit is configured to actuate the septal-closure device to expand in response to the sensor sensing that cardiac cyclic activity of the subject is at a given phase thereof. 
     
     
         66 . The apparatus according to  claim 65 , wherein the given phase includes an end-diastolic phase of the cardiac cycle, and wherein the control unit is configured to actuate the septal-closure device to expand in response to the sensor sensing the end-diastolic phase of the cardiac cycle. 
     
     
         67 . A method for use with a portion of a body of a subject that moves as a result of cyclic activity of a body system of the subject, the method comprising:
 sensing a phase of the cyclic activity; and   actuating a tool to mechanically perform an action during a single cycle of the cyclic activity with respect to the portion of the subject's body, in response to sensing that the cyclic activity is at a given phase thereof.   
     
     
         68 . The method according to  claim 67 , wherein the tool includes a balloon, and wherein actuating the balloon to perform the action comprises actuating the balloon to apposition itself to a lumen of the portion of the subject's body during a single cycle, in response to the sensing that the cyclic activity is at the given phase. 
     
     
         69 . The method according to  claim 68 , further comprising inflating the balloon continuously for a period of time prior to the balloon appositioning itself to the lumen by being inflated during the single cycle. 
     
     
         70 . The method according to  claim 68 , further comprising inflating the balloon continuously for a period of time subsequent to the balloon appositioning itself to the lumen by being inflated during the single cycle. 
     
     
         71 . The method according to  claim 67 , wherein the tool includes a stent, and wherein actuating the stent to perform the action comprises actuating the stent to expand inside a lumen of the portion of the subject's body, in response to the sensing that the cyclic activity is at the given phase. 
     
     
         72 . The method according to  claim 71 , wherein the stent includes a self-expansible portion and wherein expanding the stent comprises facilitating self-expansion of the portion of the stent. 
     
     
         73 . The method according to  claim 67 , wherein the tool includes a valve, and wherein actuating the tool to perform the action comprises actuating the valve to expand within the portion, in response to the sensing that the cyclic activity is at the given phase. 
     
     
         74 . The method according to  claim 73 , wherein the cyclic activity includes a cardiac cycle of the subject, and wherein actuating the valve comprises actuating the valve to expand in response to sensing that the cardiac cycle of the subject is at a given phase thereof. 
     
     
         75 . The method according to  claim 74 , wherein the given phase includes an end-diastolic phase of the cardiac cycle, and wherein actuating the valve comprises actuating the valve to expand in response to the sensing that the cardiac cycle of the subject is at the end-diastolic phase. 
     
     
         76 . The method according to  claim 67 , wherein the cyclic activity includes a cardiac cycle of the subject, wherein the tool includes a septal-closure device configured to be implanted within a heart of the subject by mechanically expanding within the heart, and wherein actuating the tool comprises actuating the septal-closure device to expand in response to sensing that the cardiac cycle is at a given phase thereof. 
     
     
         77 . The method according to  claim 76 , wherein the given phase includes an end-diastolic phase of the cardiac cycle, and wherein actuating the device to expand comprises actuating the device to expand in response to sensing that the cardiac cycle is at the end-diastolic phase. 
     
     
         78 . Apparatus for use with a portion of a subject's body that undergoes neural cyclic activity, the apparatus comprising:
 a sensor for sensing a phase of the neural cyclic activity;   a medical tool configured to perform a function with respect to the portion of the subject's body; and   a control unit configured to actuate the tool to perform the function, in response to the sensor sensing that the cyclic activity is at a given phase thereof.   
     
     
         79 . A method for use with a portion of a subject's body that undergoes neural cyclic activity, the method comprising:
 sensing a phase of the neural cyclic activity; and   performing a function, in response to sensing that the neural cyclic activity is at a given phase thereof.   
     
     
         80 . Apparatus for use with a portion of a body of a subject that moves as a result of cyclic activity of a body system of the subject, and for use with a sensor for sensing a phase of the cyclic activity, and for use with a medical tool configured to perform a function with respect to the portion of the subject's body, the apparatus comprising:
 a control unit configured:
 in a first cycle of the cyclic activity, to move at least a portion of the tool in a given direction, in response to the sensor sensing that the cyclic activity is at a given phase thereof, 
 following the given phase in the first cycle and prior to an occurrence of the given phase in a subsequent cycle of the cyclic activity, to inhibit the movement of the at least a portion of the tool, and 
 in a second cycle of the cyclic activity, subsequent to the inhibiting of the movement, to move the at least a portion of the tool in the given direction, in response to the sensor sensing that the second cycle of the cyclic activity is at the given phase thereof, 
 without moving the at least a portion of the tool in a direction opposite to the given direction, between (a) moving the at least a portion of the tool in the given direction in the first cycle, and (b) moving the at least a portion of the tool in the given direction in the second cycle. 
   
     
     
         81 . Apparatus for use with a portion of a body of a subject that moves as a result of cyclic activity of a body system of the subject, the apparatus comprising:
 a sensor for sensing a phase of the cyclic activity;   a medical tool configured to perform a function with respect to the portion of the subject's body; and   a control unit configured:
 in a first cycle of the cyclic activity in response to the sensor sensing that the cyclic activity is at a first given phase thereof, to move the tool, 
 in a subsequent cycle of the cyclic activity in response to the sensor sensing that the cyclic activity is at the given phase thereof, to actuate the tool to execute an action selected from the group consisting of: performing the function and moving, 
 following the given phase in the subsequent cycle and prior to an occurrence of the given phase in a further subsequent cycle of the cyclic activity, to inhibit the selected action of the tool, and 
 in the further subsequent cycle of the cyclic activity, subsequent to the inhibiting of the action, and in response to the sensor sensing that the further subsequent cycle of the cyclic activity is at the given phase thereof, to actuate the tool to execute an action selected from the group. 
   
     
     
         82 . The apparatus according to  claim 81 , wherein the tool comprises a myocardial revascularization tool configured to sequentially apply a revascularization treatment to respective treatment sites within the portion of the subject's body, and wherein the control unit is configured to:
 actuate the tool to perform the function by actuating the tool to apply a revascularization treatment to a treatment site, and   to move the tool by moving at least a portion of the revascularization tool toward successive treatment sites.   
     
     
         83 . The apparatus according to  claim 82 , wherein the control unit is configured to move the tool by moving the tool to create a defined pattern of treatment sites. 
     
     
         84 . The apparatus according to  claim 81 , wherein the tool comprises an ablation tool configured to sequentially ablate respective ablation sites within the portion of the subject's body, wherein the control unit is configured to:
 actuate the tool to perform the function by actuating the tool to ablate an ablation site, and   to move the tool by moving at least a portion of the ablation tool toward successive ablation sites.   
     
     
         85 . The apparatus according to  claim 84 , wherein the ablation tool is configured to ablate the ablation sites using an ablation technique selected from the group consisting of: laser ablation, electrocautery, RF ablation, cryogenic ablation, and ultrasound ablation. 
     
     
         86 . The apparatus according to  claim 84 , wherein the control unit is configured to move the at least the portion of the tool by moving the at least the portion of the tool to create a defined pattern of ablation sites. 
     
     
         87 . The apparatus according to  claim 84 , wherein the control unit is configured to apply a Maze procedure to the ablation sites by moving the at least the portion of the tool toward successive ablation sites. 
     
     
         88 . The apparatus according to  claim 84 , wherein the ablation tool is configured to apply a pulmonary vein isolation technique to a heart of the subject by moving the at least the portion of the tool toward successive isolation sites. 
     
     
         89 . The apparatus according to  claim 81 , wherein the tool comprises an injection tool, configured to inject a substance within the portion of the subject's body, and wherein the control unit is configured to:
 actuate the tool to perform the function by actuating the tool to inject the substance, and   to move the tool by moving at least a portion of the tool toward an injection site.   
     
     
         90 . The apparatus according to  claim 89 , wherein the substance includes DNA molecules, and wherein the injection tool is configured to inject the DNA molecules into heart tissue of the subject. 
     
     
         91 . The apparatus according to  claim 89 , wherein the substance includes stem cells, and wherein the injection tool is configured to inject the stem cells into heart tissue of the subject. 
     
     
         92 . The apparatus according to  claim 81 , wherein the tool comprises a needle configured to suture tissue within the portion of the subject's body, and wherein the control unit is configured to:
 actuate the tool to perform the function by actuating the tool to suture the tissue, and   to move the tool by moving the needle toward successive suturing sites.   
     
     
         93 . The apparatus according to  claim 92 , wherein the tissue includes tissue of the subject selected from the group consisting of cardiac tissue and coronary tissue, and wherein the needle is configured to suture the selected tissue. 
     
     
         94 . The apparatus according to  claim 81 , wherein the tool comprises a needle configured to aspirate tissue from an aspiration site within the portion of the subject's body, and wherein the control unit is configured to:
 actuate the needle to perform the function by actuating the needle to aspirate the tissue, and   move the needle by moving the needle toward the aspiration site.   
     
     
         95 . The apparatus according to  claim 94 , wherein the needle is configured to perform trans-thoracic needle aspiration. 
     
     
         96 . The apparatus according to  claim 94 , wherein the needle is configured to perform trans-bronchial needle aspiration. 
     
     
         97 . A method for use with a portion of a body of a subject that moves as a result of cyclic activity of a body system of the subject, the method comprising:
 sensing a phase of the cyclic activity;   in a first cycle of the cyclic activity in response to sensing that the cyclic activity is at a first given phase thereof, moving a tool that is configured to perform a function;   in a subsequent cycle of the cyclic activity in response to sensing that the cyclic activity is at the given phase thereof, actuating the tool to execute at least one action selected from the group consisting of: performing the function and moving;   following the given phase in the subsequent cycle and prior to an occurrence of the given phase in a further subsequent cycle of the cyclic activity, inhibiting the selected action of the tool; and   in the further subsequent cycle of the cyclic activity, subsequent to the inhibiting of the action, and in response to sensing that the further subsequent cycle of the cyclic activity is at the given phase thereof, actuating the tool to execute at least one of the actions selected from the group.   
     
     
         98 . The method according to  claim 97 ,
 wherein the tool includes a needle configured to suture tissue within the portion of the subject's body,   wherein actuating the tool to perform the function comprises actuating the tool to suture the tissue, and   wherein moving the tool comprises moving at least a portion of the tool toward successive suturing sites.   
     
     
         99 . The method according to  claim 97 ,
 wherein the tool includes a myocardial revascularization tool configured to sequentially apply a revascularization treatment to respective treatment sites within the portion of the subject's body,   wherein actuating the tool to perform the function comprises actuating the tool to apply a revascularization treatment to a treatment site, and wherein moving the tool comprises moving at least a portion of the revascularization tool toward successive treatment sites.   
     
     
         100 . The method according to  claim 99 , wherein moving at least a portion of the revascularization tool toward successive treatment sites comprises moving the at least the portion of the tool to create a defined pattern of treatment sites. 
     
     
         101 . The method according to  claim 97 ,
 wherein the tool includes an ablation tool configured to sequentially ablate respective ablation sites within the portion of the subject's body,   wherein actuating the tool to perform the function comprises actuating the tool to ablate an ablation site, and   wherein moving the tool comprises moving at least a portion of the ablation tool toward successive ablation sites.   
     
     
         102 . The method according to  claim 101 , wherein moving the at least the portion of the tool comprises moving the at least the portion of the tool to create a defined pattern of ablation sites. 
     
     
         103 . The method according to  claim 101 , wherein moving the at least the portion of the tool comprises moving the at least the portion of the tool to apply a Maze procedure to the ablation sites. 
     
     
         104 . The method according to  claim 101 , wherein moving the at least the portion of the tool comprises moving the at least the portion of the tool to apply a pulmonary vein isolation technique to a heart of the subject. 
     
     
         105 . The method according to  claim 97 ,
 wherein the tool includes an injection tool configured to inject a substance-within the portion of the subject's body,   wherein actuating the tool to perform the function comprises actuating the tool to inject the substance, and   wherein moving the tool comprises moving at least a portion of the tool toward an injection site.   
     
     
         106 . The method according to  claim 105 , wherein actuating the tool to inject the substance comprises actuating the tool to inject DNA molecules into heart tissue of the subject. 
     
     
         107 . The method according to  claim 105 , wherein actuating the tool to inject the substance comprises actuating the tool to inject stem cells into heart tissue of the subject. 
     
     
         108 . The method according to  claim 97 ,
 wherein the tool includes a needle configured to aspirate tissue from an aspiration site within the portion of the subject's body,   wherein actuating the tool to perform the function comprises actuating the needle to aspirate the tissue, and   wherein moving the tool comprises moving the needle toward the aspiration site.   
     
     
         109 . The method according to  claim 108 , wherein actuating the needle to aspirate the tissue comprises actuating the needle to perform trans-thoracic needle aspiration. 
     
     
         110 . The method according to  claim 108 , wherein actuating the needle to aspirate the tissue comprises actuating the needle to perform trans-bronchial needle aspiration. 
     
     
         111 . Apparatus for opening an at least partial occlusion of a lumen of a subject's body, the apparatus comprising:
 a sensor for sensing a phase of the cyclic activity;   an occlusion-opening tool configured to open the occlusion; and   a control unit configured:
 in a first cycle of the cyclic activity in response to the sensor sensing that the cyclic activity is at a first given phase thereof, to actuate the tool to perform an occlusion-opening action, 
 following the given phase in the first cycle and prior to an occurrence of the given phase in a subsequent cycle of the cyclic activity, to inhibit the action of the tool, and 
 in a second cycle of the cyclic activity, subsequent to the inhibiting of the action, and in response to the sensor sensing that the second cycle of the cyclic activity is at the given phase, to actuate the tool to perform the action. 
   
     
     
         112 . The apparatus according to  claim 111 , wherein after actuating the tool at the given phase of the first cycle and before the actuation of the tool at the given phase of the subsequent cycle, the control unit is configured to retract the tool from the occlusion. 
     
     
         113 . The apparatus according to  claim 111 , wherein the occlusion-opening tool comprises a tool configured to open the occlusion by directing acoustic waves toward the occlusion. 
     
     
         114 . A method for opening an at least partial occlusion of a lumen of a subject's body, the method comprising:
 sensing a phase of the cyclic activity;   in a first cycle of the cyclic activity in response to sensing that the cyclic activity is at a first given phase thereof, to actuate an occlusion-opening tool to perform an occlusion-opening action;   following the given phase in the first cycle and prior to an occurrence of the given phase in a subsequent cycle of the cyclic activity, to inhibit the action of the tool; and   in a second cycle of the cyclic activity, subsequent to the inhibiting of the action, and in response to sensing that the second cycle of the cyclic activity is at the given phase, to actuate the tool to perform the action.   
     
     
         115 . The method according to  claim 114 , further comprising retracting the tool from the occlusion after actuating the tool at the given phase of the first cycle and before the actuation of the tool at the given phase of the subsequent cycle. 
     
     
         116 . The method according to  claim 114 , wherein actuating the tool to perform the occlusion-opening action comprises actuating the tool to direct acoustic waves toward the occlusion.