Rapid exchange infusion catheter

Abstract

An infusion catheter and method, with an elongated shaft having a guidewire lumen which has a proximal section and a common distal section extending to a distal port at a distal end of the shaft, and an infusion lumen which is in fluid communication with the distal port of the guidewire lumen and which joins the common distal section of the guidewire lumen at a location distal to the guidewire proximal port. A restricted passage from the infusion lumen to the common distal section of the guidewire lumen has a smaller transverse dimension than the guidewire lumen and a guidewire slidably disposed in the guidewire lumen.

1 . An infusion balloon catheter, comprising:
 a) an elongated shaft having a proximal end, a distal end, an inflation lumen, a guidewire lumen which has a proximal section and a common distal section and which extends from a guidewire distal port at the shaft distal end to a guidewire proximal port spaced distally from the proximal end of the shaft, and an infusion lumen which is in fluid communication with the guidewire distal port and which extends alongside the proximal section of the guidewire lumen and proximally of the guidewire proximal port to the proximal end of the shaft, and which joins the common distal section of the guidewire lumen at a location distal to the guidewire proximal port and proximal to a distal end of the inflation lumen, with a restricted passage from the infusion lumen to the common distal section of the guidewire lumen having a smaller transverse dimension than at least a portion of the guidewire lumen so that the passage is configured to prevent a guidewire from slidably extending therethrough between the infusion and guidewire lumens; and   b) an inflatable balloon on a distal section of the elongated shaft, having an interior in fluid communication with the inflation lumen.   
     
     
         2 . The balloon catheter of  claim 1  wherein the restricted passage from the infusion lumen to the common distal section of the guidewire lumen is a crescent-shaped section of the infusion lumen extending along at least a portion of the proximal section of the guidewire lumen. 
     
     
         3 . The balloon catheter of  claim 2  wherein the infusion lumen has a circular-shaped proximal section located proximal to the crescent-shaped section. 
     
     
         4 . The balloon catheter of  claim 3  wherein the proximal section of the infusion lumen has an inner diameter which is larger than the transverse dimension of the crescent-shaped section of the infusion lumen. 
     
     
         5 . The balloon catheter of  claim 3  wherein the crescent-shaped section of the infusion lumen has a proximal end, a distal end and a length extending from the proximal to the distal end thereof, and the length of the crescent-shaped section is substantially equal to the length of the proximal section of the guidewire lumen which extends alongside the infusion lumen. 
     
     
         6 . The balloon catheter of  claim 1  wherein the restricted passage from the infusion lumen to the common distal section of the guidewire lumen is a noncircular section of the infusion lumen extending along at least a portion of the proximal section of the guidewire lumen. 
     
     
         7 . The balloon catheter of  claim 1  wherein the infusion lumen has a circular transverse cross sectional shape along an entire length thereof, such that the restricted passage from the infusion lumen to the common distal section of the guidewire lumen is a circular-shaped section of the infusion lumen having a smaller inner diameter than both the common distal section of the guidewire lumen and a circular-shaped proximal section of the infusion lumen. 
     
     
         8 . The balloon catheter of  claim 1  wherein the infusion lumen is defined by a first inner tubular member having a proximal end at the proximal end of the shaft and a distal end located distal to the guidewire proximal port, and the guidewire lumen proximal section is defined by a second inner tubular member having a proximal end at the guidewire proximal port. 
     
     
         9 . The balloon catheter of  claim 8  wherein the second inner tubular member defining the guidewire lumen proximal section has a distal end at the distal end of the restricted passage from the infusion lumen to the common distal section of the guidewire lumen, such that the common distal section of the guidewire lumen is defined by a distal section of the first inner tubular member. 
     
     
         10 . The balloon catheter of  claim 9  wherein the shaft includes an outer tubular member around the first and second inner tubular members, and the inflation lumen is within the outer tubular member around the first and second inner tubular members. 
     
     
         11 . The balloon catheter of  claim 1  wherein the inflation lumen has an annular proximal section, an annular distal section, and a crescent-shaped section therebetween along the proximal section of the guidewire lumen. 
     
     
         12 . The balloon catheter of  claim 1  wherein a distal tip of the shaft distal to an inflatable interior of the balloon has a single lumen circular transverse cross section with a circular section of the common distal section of the guidewire lumen therein. 
     
     
         13 . An infusion balloon catheter, comprising:
 a) an elongated shaft having a proximal end, a distal end, an inflation lumen, a guidewire lumen which has a circular-shaped transverse cross section and which is configured to slidably receive a guidewire therethrough and which extends from a guidewire distal port at the shaft distal end to a guidewire proximal port spaced distally from the proximal end of the shaft, and an infusion lumen having a proximal section which has a circular-shaped transverse cross section and which extends proximally of the guidewire proximal port to the proximal end of the shaft, and a distal section which has crescent-shaped transverse cross section and which extends alongside a proximal section of the guidewire lumen and which joins the guidewire lumen at a distal end of the crescent-shaped section such that the infusion lumen is in fluid communication with the guidewire distal port through a common distal section of the guidewire lumen; and   b) an inflatable balloon on a distal section of the elongated shaft, having an interior in fluid communication with the inflation lumen.   
     
     
         14 . An infusion catheter, comprising an elongated shaft having a proximal end, a distal end, and
 a) a first lumen which extends from the shaft proximal end toward the shaft distal end;   b) a guidewire lumen which is configured to slidably receive a guidewire therein and which has a proximal section and a common distal section, and which extends from a distal port at the shaft distal end to a proximal port spaced distally from the proximal end of the shaft, the guidewire lumen being off-set from the first lumen to not communicate with the first lumen; and   c) an infusion lumen which is in fluid communication with the distal port of the guidewire lumen, and which extends alongside the proximal section of the second lumen and proximally of the second lumen proximal port to the proximal end of the shaft, and which joins the common distal section of the guidewire lumen at a location distal to the guidewire proximal port and proximal to a distal end of the first lumen, with a restricted passage from the infusion lumen to the common distal section of the guidewire lumen having a smaller inner transverse dimension than at least a portion of the guidewire lumen so that the passage is configured to prevent a guidewire from slidably extending therethrough between the infusion and guidewire lumens.   
     
     
         15 . A method of performing a medical procedure in a patient's body lumen, comprising:
 a) advancing within the patient's body lumen an infusion balloon catheter comprising an elongated shaft having a proximal end, a distal end, an inflation lumen, a guidewire lumen which has a proximal section and a common distal section and which extends from a guidewire distal port at the shaft distal end to a guidewire proximal port spaced distally from the proximal end of the shaft, and an infusion lumen which is in fluid communication with the guidewire distal port, and which extends alongside the proximal section of the guidewire lumen and proximally of the guidewire proximal port to the proximal end of the shaft, and which joins the common distal section of the guidewire lumen at a location distal to the guidewire proximal port and proximal to a distal end of the inflation lumen, and a balloon on a distal section of the elongated shaft having an interior in fluid communication with the inflation lumen;   b) positioning the distal end of the shaft at a desired location in the body lumen, with a guidewire slidably disposed in the guidewire lumen, the guidewire having a proximal end and a distal end and extending from the guidewire proximal port to the guidewire distal port; and   c) proximally retracting the guidewire relative to the shaft to position a distal section of the guidewire in the proximal section of the guidewire lumen, and delivering a fluid to the patient's body lumen with the guidewire in the proximally retracted position, by infusing the fluid through the infusion lumen to the common distal section of the guidewire lumen and out the guidewire distal port.   
     
     
         16 . The method of  claim 15  wherein the infusion lumen joins the guidewire lumen with a restricted passage from the infusion lumen to the guidewire lumen having a smaller transverse dimension than the guidewire lumen so that the passage is configured to prevent the proximal end of the guidewire from slidably extending proximally therethrough into the infusion lumen, and wherein before (b) the catheter is slidably disposed over the guidewire by threading the guidewire proximal end into the guidewire distal port, through the guidewire lumen, and out guidewire proximal port. 
     
     
         17 . The method of  claim 16  wherein the restricted passageway has a transverse cross section with a crescent-shape which is narrower in a first direction than in a perpendicular second direction, and the guidewire proximal end has a circular transverse cross section with a larger diameter than the narrower first direction of the crescent-shaped restricted passageway such that the guidewire proximal end is prevented from entering the infusion lumen by the restricted passage. 
     
     
         18 . The method of  claim 15  wherein the guidewire in the proximally retracted position substantially occludes the proximal section of the guidewire lumen to thereby inhibit the fluid from back-flowing proximally out the guidewire proximal port, and including longitudinally displacing the guidewire in the guidewire lumen after c) to slidably dispose the guidewire distal end through the guidewire distal port. 
     
     
         19 . The method of  claim 15  including inflating the balloon after b) and before c).