Ultrasound catheter and methods for making and using same

Abstract

Ultrasound catheter devices and methods provide enhanced disruption of blood vessel obstructions. Generally, ultrasound catheters include an elongate flexible catheter body with one or more lumens, an ultrasound transmission member extending longitudinally through the catheter body lumen and, in some embodiments, a guidewire tube extending through the lumen. A distal head for disrupting occlusions is coupled with the distal end of the ultrasound transmission member and is positioned adjacent the distal end of the catheter body. Some embodiments include improved features such as a bend in the catheter body for enhancing positioning and/or advancement of the catheter.

1 . A method for disrupting an obstruction in an artery by delivering a medicament into the artery and enhancing absorption of the medicament into a wall of the artery using ultrasound energy, the method comprising:
 advancing a distal end of a combined ultrasound/drug delivery catheter to an obstruction in an artery;   delivering a medicament into the artery from the ultrasound/drug delivery catheter; and   activating the ultrasound catheter to emit ultrasound energy while delivering the medicament.   
     
     
         2 . The method of  claim 1 , wherein delivery of the ultrasonic energy causes vasodilatation within vessel wall without vascular damage. 
     
     
         3 . The method of  claim 1 , wherein the medicament is delivered from the ultrasound/drug delivery catheter at or near the distal end, and wherein activating the ultrasound/drug delivery catheter converts the medicament into droplets. 
     
     
         4 . The method of  claim 3 , wherein the medicament is dispersed at constant rate. 
     
     
         5 . The method of  claim 3 , wherein the plurality of outlet apertures are arrayed around the distal end of the ultrasound catheter. 
     
     
         6 . The method of  claim 3 , wherein a medicament is dispersed with variable rate. 
     
     
         7 . The method of  claim 1 , wherein the medicament is delivered through a lumen to the distal end of the ultrasound/drug delivery catheter. 
     
     
         8 . The method of  claim 1 , wherein the medicament is delivered through more than one lumen to the distal end of the ultrasound/drug delivery catheter. 
     
     
         9 . The method of  claim 3 , wherein the medicament is delivered in radial fashion through at least one of outlet ports located in the distal tip of the ultrasound/drug delivery catheter or outlet ports located on the ultrasound catheter body proximal to the distal tip. 
     
     
         10 . The method of  claim 1 , further comprising delivering an irrigation fluid through the ultrasound catheter while activating the ultrasound catheter to emit ultrasound energy. 
     
     
         11 . The method of  claim 10 , wherein the irrigation fluid and the medicament are delivered together in a mixture. 
     
     
         12 . The method of  claim 10 , wherein the irrigation fluid is delivered separately from the medicament. 
     
     
         13 . The method of  claim 12 , further comprising introducing an irrigation fluid via one or more lumens on the ultrasound/drug delivery catheter that are separate from one or more medicament lumens. 
     
     
         14 . The method of  claim 1 , wherein the medicament is oxygenated. 
     
     
         15 . The method of  claim 1 , wherein the medicament is in liquid form. 
     
     
         16 . The method of  claim 1 , further comprising repositioning the ultrasound/drug delivery catheter; and activating the ultrasound/drug delivery catheter to further enhance delivery of the medicament. 
     
     
         17 . The method of  claim 1 , further comprising positioning a sheath over the combined ultrasound/drug delivery catheter. 
     
     
         18 . The method of  claim 17 , wherein the sheath is positioned to a location distal to the ultrasound catheter distal tip or proximal to the ultrasound catheter distal tip. 
     
     
         19 . The method of  claim 17 , wherein the sheath comprises a polymer. 
     
     
         20 . The method of  claim 17 , further comprising delivering the medicament from a location outside the body. 
     
     
         21 . The method of  claim 1 , wherein advancing the ultrasound/drug delivery catheter comprises advancing it in a manner selected from the group consisting of monorail, over-the-wire and without a guidewire. 
     
     
         22 . The method of  claim 1 , wherein the ultrasound catheter operates in a mode selected from the group consisting of continuous mode, pulse mode and a combination continuous/pulse mode. 
     
     
         23 . The method of  claim 1 , wherein advancing the ultrasound/drug delivery catheter comprises contacting the wall of the blood vessel with the catheter. 
     
     
         24 . The method of  claim 1 , wherein the emitted ultrasound energy is modulated. 
     
     
         25 . The method of  claim 1 , further comprising performing an ultrasound angioplasty procedure before, during or after delivery of the medicament and ultrasound energy. 
     
     
         26 . The method of  claim 25 , wherein performing the angioplasty procedure comprises advancing an sheath over a guidewire to the area of occlusion in the artery, and wherein the combined ultrasound/drug delivery catheter is advanced over the same guidewire. 
     
     
         27 . A method for treating an occlusion in an artery by delivering a medicament to the artery, and enhancing absorption of the medicament using ultrasound energy, the method comprising:
 advancing a distal portion of a combined ultrasound/drug delivery catheter to an area of occlusion an artery;   delivering a medicament into the artery through the catheter; and   activating the catheter to emit ultrasound energy while delivering the medicament.   
     
     
         28 . A method for treating an occlusion in an artery by delivering a medicament to the artery and enhancing absorption of the medicament using ultrasound energy, the method comprising:
 advancing a distal portion of a combined ultrasound/drug delivery catheter to an area of occlusion in an artery;   advancing a sheath over the combined ultrasound/drug delivery catheter;   delivering a medicament into the artery through the catheter; and   activating the catheter to emit ultrasound energy while delivering the medicament.   
     
     
         29 . The method of  claim 28 , wherein the sheath surrounds a portion of the distal head of the combined ultrasound/drug delivery catheter. 
     
     
         30 . The method of  claim 28 , wherein the sheath comprises a polymer. 
     
     
         31 . The method of  claim 28 , wherein expanding the sheath couples a connector device with the catheter body. 
     
     
         32 . The method of  claim 28 , wherein the sheath maintains a bend in the catheter body. 
     
     
         33 . A method of treating occlusions comprising:
 introducing an ultrasound dispersed medicament to a treatment area; and   activating ultrasound energy to cause passage of the medicament into the vessel wall.   
     
     
         34 . A method for treating a totally occluded artery by delivering a medicament into the artery and enhancing absorption of the medicament into a wall of the artery using ultrasound energy, the method comprising:
 advancing a distal end of a combined ultrasound/drug delivery catheter to an area of a totally occluded artery;   delivering a medicament into the artery from the ultrasound/drug delivery catheter; and   activating the ultrasound catheter to emit ultrasound energy while delivering the medicament.   
     
     
         35 . The method of  claim 34 , wherein advancing a distal end of a combined ultrasound/drug delivery catheter to an area of occlusion in an artery is performed without ablating or removing plaque material. 
     
     
         36 . The method of  claim 34 , wherein treating a totally occluded artery by delivering a medicament into the artery and enhancing absorption of the medicament into a wall of the artery using ultrasound energy includes ablating or removal of material.