Curved catheter

Abstract

Apparatus and methods are described including inserting a catheter into a subject's body via a vein of the subject's groin. The catheter is advanced distally such that a distal end of the catheter is disposed inside the subject's renal vein. Respective stabilizing portions of the catheter stabilize the catheter by being in contact with inner walls of, respectively, an iliac vein of the subject, and a vena cava of the subject. Subsequently, a medical device is deployed inside the renal vein by retracting the distal end of the catheter, such that the distal end of the catheter is in a retracted state, in which the respective stabilizing portions of the catheter still stabilize the catheter by being in contact with the inner walls of, respectively, the subject's iliac vein and the subject's vena cava. Other applications are also described.

1 . An apparatus, comprising:
 a medical device that is configured to be inserted into a body of a subject; and   a catheter that defines a continuous tube that defines a lumen therethrough, the medical device being configured to be inserted into the subject's body via the catheter, the continuous tube comprising at least first, second, third, fourth, and fifth portions thereof,   the first portion being disposed at a first end of the catheter and being shaped, when the catheter is in a non-constrained configuration, to define a cylindrical portion of the tube that defines a generally straight central longitudinal axis;   the second portion being disposed adjacent to the first portion and being shaped, when the catheter is in the non-constrained configuration, to define a curved cylindrical portion of the tube, a curvature of the second portion being such that a central longitudinal axis of the second portion defines a curve that is concave in a given direction, and that curves outwardly away from the central longitudinal axis of the first portion;   the third portion being disposed between the second and the fourth portions and being shaped, when the catheter is in the non-constrained configuration, to define a curved cylindrical portion of the tube, a curvature of the third portion being such that a central longitudinal axis of the third portion defines a curve that is convex in the given direction, and that curves inwardly toward the central longitudinal axis of the first portion, such that the central longitudinal axis of the third portion meets the central longitudinal axis of the first portion,   the fourth portion being disposed between the third and the fifth portions of the tube, and being shaped, when the catheter is in the non-constrained configuration, to define a curved cylindrical tube, a curvature of the fourth portion being such that a central longitudinal axis of the fourth portion defines a curve that is concave in the given direction, and that curves away from the central longitudinal axis of the first portion,   the fifth portion being disposed at a second end of the catheter the fifth portion being shaped, when the catheter is in the non-constrained configuration, to define a curved cylindrical tube, a curvature of the fifth portion being such that a central longitudinal axis of the fifth portion defines a curve that is concave in the given direction, and that curves inwardly toward the central longitudinal axis of the first portion.   
     
     
         2 . The apparatus according to  claim 1 , wherein the continuous tube defined by the catheter further comprises a sixth portion disposed between the second and third portions of the tube, the sixth portion of the tube defining a cylindrical portion of the tube that defines a generally straight central longitudinal axis, when the catheter is in the non-constrained configuration. 
     
     
         3 . The apparatus according to  claim 1 , wherein a flexibility of at least a distal tip of the fifth portion is greater than a flexibility of each of the first, second, third, and fourth portions. 
     
     
         4 . The apparatus according to  claim 1 , wherein at least a tip of the fifth portion is atraumatic. 
     
     
         5 . The apparatus according to  claim 1 , wherein the medical device has a given length, and wherein, when the catheter is in the non-constrained configuration, a length of the second portion of the tube, measured along the longitudinal axis of the second portion, is at least twice the length of the medical device. 
     
     
         6 . The apparatus according to  claim 5 , wherein the length of the second portion of the tube is at least 3 times the length of the medical device. 
     
     
         7 . The apparatus according to  claim 1 , wherein the medical device has a given length, and wherein, a length of the third portion of the tube, measured along the longitudinal axis of the third portion, is at least twice the length of the medical device. 
     
     
         8 . The apparatus according to  claim 7 , wherein the length of the third portion of the tube is at least 3 times the length of the medical device. 
     
     
         9 . The apparatus according to  claim 1 , wherein:
 the catheter is configured to be:
 inserted into the subject's body via a blood vessel of a groin of the subject, and 
 advanced distally such that the fifth portion of the catheter is inserted into a renal vessel that is contralateral to the blood vessel of the subject's groin; and 
   the medical device is configured to be deployed inside the contralateral renal vessel by the catheter being retracted proximally, subsequent to insertion of the fifth portion of the catheter into the contralateral renal vessel.   
     
     
         10 . The apparatus according to  claim 9 , wherein, when the fifth portion of the catheter is disposed inside the renal vessel, and prior to deploying the medical device by the catheter being retracted proximally, the second portion is configured to stabilize the catheter by contacting an inner wall of an iliac vessel of the subject. 
     
     
         11 . The apparatus according to  claim 9 , wherein, when the fifth portion of the catheter is disposed inside the renal vessel, and prior to deploying the medical device by the catheter being retracted proximally, the third portion is configured to stabilize the catheter by contacting an inner wall of a vessel of the subject selected from the group consisting of: a vena cava of the subject, and an aorta of the subject. 
     
     
         12 . The apparatus according to  claim 9 , wherein, when the fifth portion of the catheter is disposed inside the renal vessel, and prior to deploying the medical device by the catheter being retracted proximally, the fourth portion is configured to stabilize the catheter by contacting an inner wall of the renal vessel. 
     
     
         13 . The apparatus according to  claim 9 , wherein, subsequent to deployment of the device in the contralateral renal vessel by the catheter having been retracted proximally, the second portion is configured to stabilize the catheter by contacting an inner wall of an iliac vessel of the subject. 
     
     
         14 . The apparatus according to  claim 9 , wherein, subsequent to deployment of the device in the contralateral renal vessel by the catheter having been retracted proximally, the third portion is configured to stabilize the catheter by contacting an inner wall of a vessel of the subject selected from the group consisting of: a vena cava of the subject, and an aorta of the subject. 
     
     
         15 . The apparatus according to  claim 9 , wherein, subsequent to deployment of the device in the contralateral renal vessel by the catheter having been retracted proximally, the fourth portion is configured to stabilize the catheter by contacting an inner wall of the renal vessel. 
     
     
         16 . The apparatus according to  claim 1 , wherein:
 the catheter is configured to be:
 inserted into the subject's body via a blood vessel of a groin of the subject, and 
 advanced distally such that the fifth portion of the catheter is inserted into a renal vessel that is ipsilateral to the blood vessel of the subject's groin; and 
   the medical device is configured to be deployed inside the contralateral renal vessel by the catheter being retracted proximally, subsequent to insertion of the fifth portion of the catheter into the ipsilateral renal vessel.   
     
     
         17 . The apparatus according to  claim 16 , wherein, when the fifth portion of the catheter is disposed inside the renal vessel, and prior to deploying the medical device by the catheter being retracted proximally, the second portion is configured to stabilize the catheter by contacting an inner wall of an iliac vessel of the subject. 
     
     
         18 . The apparatus according to  claim 16 , wherein, when the fifth portion of the catheter is disposed inside the renal vessel, and prior to deploying the medical device by the catheter being retracted proximally, the third portion is configured to stabilize the catheter by contacting an inner wall of a vessel of the subject selected from the group consisting of: a vena cava of the subject, and an aorta of the subject. 
     
     
         19 . The apparatus according to  claim 16 , wherein, when the fifth portion of the catheter is disposed inside the renal vessel, and prior to deploying the medical device by the catheter being retracted proximally, the fourth portion is configured to stabilize the catheter by contacting an inner wall of the renal vessel. 
     
     
         20 . The apparatus according to  claim 16 , wherein, subsequent to deployment of the device in the ipsilateral renal vessel by the catheter having been retracted proximally, the second portion is configured to stabilize the catheter by contacting an inner wall of an iliac vessel of the subject. 
     
     
         21 . The apparatus according to  claim 16 , wherein, subsequent to deployment of the device in the ipsilateral renal vessel by the catheter having been retracted proximally, the third portion is configured to stabilize the catheter by contacting an inner wall of a vessel of the subject selected from the group consisting of: a vena cava of the subject, and an aorta of the subject. 
     
     
         22 . The apparatus according to  claim 16 , wherein, subsequent to deployment of the device in the ipsilateral renal vessel by the catheter having been retracted proximally, the fourth portion is configured to stabilize the catheter by contacting an inner wall of the renal vessel. 
     
     
         23 . The apparatus according to  claim 1 , wherein the medical device comprises a radially-expandable impeller disposed inside a radially-expandable cage. 
     
     
         24 . The apparatus according to  claim 23 , wherein a length of cage, measured along a longitudinal axis of the cage, when the cage is in a radially expanded configuration, is between 17 mm and 26 mm.