Catheter with multifunctional microinjection-molded housing

Abstract

An electrophysiology catheter has a distal electrode section having a generally-cylindrical, hollow housing body, a lumen and an opening in a sidewall. A flex circuit has a first portion supported on the outer surface the housing body, and a second portion that extends into the lumen via the opening for connection to cables and/or wires in the lumen. The flex circuit has a first and second magnetic field sensing coil traces generally perpendicular to each other and a magnetic field sensing coil wire generally perpendicular thereto is wound around the housing body to form an x/y/z position sensor. One or more ring electrodes are carried on the housing body, separated by ring spacers. A force sensor is mounted on a distal end of the housing body, with strain gauges electrically connected to the flex circuit. The housing is configured to provide a distal anchor for a puller tensile.

What is claimed is: 
     
         1 . An electrophysiology catheter having:
 an elongated catheter body;   a deflection section distal of the catheter body;   a distal electrode section having:
 a housing with a generally-cylindrical, hollow housing body with an outer surface, the housing body defining a lumen and an opening in a sidewall allowing access into the lumen, and the housing body comprising:
 a distal portion having a distal outer diameter, and a distal end portion having a distal end diameter, and 
 a proximal portion having a proximal outer diameter, 
 the distal outer diameter being smaller than the proximal outer diameter such that the housing body has a first step at a junction between the distal portion and the proximal portion, and 
 the distal end diameter of the distal end portion being smaller than the distal outer diameter of the distal portion such that the housing body has a second step distal of the first step, and 
 
 a flex circuit having a first portion supported on the outer surface of the housing body and a second portion extending into the lumen via the opening in the housing body; and 
   a control handle proximal of the catheter body.   
     
     
         2 . The catheter of  claim 1 , wherein the flex circuit has a first magnetic field sensing coil trace, and a second magnetic field sensing coil trace generally perpendicular to the first magnetic field sensing coil. 
     
     
         3 . The catheter of  claim 2 , wherein the first and second magnetic field sensing coil traces are electrically connected to one or more cables extending through the catheter body and the deflection section. 
     
     
         4 . The catheter of  claim 3 , wherein the distal electrode section includes a magnetic field sensing coil wire wound around the housing body, the third magnetic field sensing coil wire being generally perpendicular to the first and second magnetic field sensing coil traces. 
     
     
         5 . The catheter of  claim 4 , wherein the outer surface of the housing body has a circumferential recess and the third magnetic field sensing coil wire is situated in the circumferential recess. 
     
     
         6 . The catheter of  claim 1 , wherein the distal electrode assembly includes a ring electrode and a ring spacer on the outer surface of the housing body. 
     
     
         7 . The catheter of  claim 6 , wherein the housing body has a ridge at its proximal end, and the ring electrode abuts the ridge, and the ring spacer abuts the ring electrode. 
     
     
         8 . The catheter of  claim 6 , wherein the housing body has a ridge at its proximal end, and the ring spacer abuts the ridge, and the ring electrode abuts the ring spacer. 
     
     
         9 . The catheter of  claim 1 , wherein the opening in the housing body comprises a proximal edge that lies along the first step and a distal edge having an arcuate configuration. 
     
     
         10 . The catheter of  claim 1 , wherein the housing body further comprises an annular ridge at its proximal end, the annular ridge having an outer ridge diameter greater than the proximal outer diameter of the proximal portion of the housing body. 
     
     
         11 . The catheter of  claim 1 , wherein the lumen is partially occluded at least at its distal end by a partial peripheral lip that projects inwardly into the lumen. 
     
     
         12 . The catheter of  claim 11 , further comprising a puller member having first and second proximal portions and U-bend portion connecting the first and second proximal portions,
 wherein the partial peripheral lip comprises first and second axial through holes connected by a curved elongated recess on a distal face of the lip, the first and second axial through holes configured to receive the first and second portions of the puller member, and the curved elongated recess configured to receive the U-bend portion of the puller member.   
     
     
         13 . The catheter of  claim 1 , wherein the distal electrode section includes a tip electrode distal of the housing body, the tip electrode having a shell portion, a plug portion and an internal chamber configured to receive fluid. 
     
     
         14 . The catheter of  claim 13 , wherein the catheter includes a fluid tubing extending through the catheter body and the deflection and into the distal electrode section, the fluid tubing having a distal end configured to pass fluid into the internal chamber of the tip electrode. 
     
     
         15 . The catheter of  claim 1 , wherein the first portion of the flex circuit is supported on the distal portion of the housing body. 
     
     
         16 . The catheter of  claim 15 , wherein a magnetic field sensing coil wire is wound on the proximal portion of the housing body. 
     
     
         17 . The catheter of  claim 1 , wherein the flex circuit has a T-configuration in which the first portion is generally rectangular and wrapped around the outer surface of the distal portion of the housing body, and the second portion is elongated and extends from the first portion into the lumen via the opening in the housing body. 
     
     
         18 . The catheter of  claim 17 , wherein the first portion of the flex circuit comprises a first magnetic field sensing coil trace, and a second magnetic field sensing coil trace generally perpendicular to the first magnetic field sensing coil. 
     
     
         19 . The catheter of  claim 18 , wherein the second portion of the flex circuit comprises connection pads that connect to one or more electrical components and are configured to pass electrical signals arising in the first and second magnetic field sensing coil traces toward the control handle.