Pressure-sensing catheters for improved frequency response, and related devices and methods of use thereof

A pressure-sensing medical device, comprising:

• a pressure-sensing catheter including:
• an elongate catheter body extending from a proximal end to a distal end and having an outer surface;
• a primary lumen extending along at least a portion of the elongate catheter body;
• one or more secondary lumens extending along at least a portion of the elongate catheter body, the one or more secondary lumens exhibiting a non-circular cross-sectional shape;
• and
• at least one collapsible vessel disposed on the body, each collapsible vessel in fluid communication with a secondary lumen of the one or more secondary lumens;
• and
• a pressure-sensing transducer located and configured to sense a pressure within the at least one collapsible vessel and the secondary lumen of the one or more secondary lumens.

A method of manufacturing a pressure-sensing catheter, the method comprising:

• extruding an elongate catheter shaft having a proximal end and a distal end, the catheter shaft including a polymeric shaft wall defining a primary lumen extending between the proximal and distal ends and at least one secondary lumen extending between the proximal and distal ends, wherein the at least one secondary lumen has a non-circular cross-sectional shape;
• forming, in a distal portion of the catheter shaft, at least one opening extending between the at least one secondary lumen and an exterior of the catheter shaft;
• positioning a compliant member about the distal portion of the catheter shaft over the at least one opening, the compliant member having a proximal cuff portion and a distal cuff portion contacting an outer surface of the catheter shaft;
• and
• laser-welding the compliant member to the catheter shaft to form a sealed chamber in fluid communication with the at least one secondary lumen, wherein laser-welding comprises:
• performing a first low-power laser pass along a first side of the compliant member, the first low-power laser pass beginning adjacent a first edge of the compliant member and translating axially away from the compliant member to apply heat sufficient to conform the compliant member to the catheter shaft;
• performing a second low-power laser pass along the first side, the second low-power laser pass beginning adjacent the first edge of the compliant member and translating axially away from the compliant member to melt and fuse compliant member material to shaft material to create a first weld seam;
• performing a third low-power laser pass along a second side of the compliant member opposite the first side, the third low-power laser pass beginning adjacent a second edge of the compliant member and translating axially away from the compliant member;
• and
• performing a fourth low-power laser pass along the second side, the fourth low-power laser pass beginning adjacent the second edge of the compliant member and translating axially away from the compliant member to melt and fuse compliant member material to shaft material to create a second weld seam;
• wherein the first and second weld seams cooperate to seal the compliant member to the catheter shaft while maintaining patency of the primary lumen and the at least one secondary lumen.