Electrode design for directional lithotripsy catheters

A catheter for treating an occlusion in a body lumen, the catheter comprising:

• a fluid lumen configured to receive a conductive fluid and direct the conductive fluid out of a distal end of the catheter;
• an electrode assembly including (i) a cylindrical inner conductive ring having an uninsulated distal side edge that extends circumferentially around a longitudinal axis of the cylindrical inner conductive ring, and (ii) a cylindrical outer conductive ring spaced apart from the inner conductive ring, the outer conductive ring having a distal side edge adjacent to the distal side edge of the inner conductive ring;
• and
• an insulator positioned between the outer conductive ring and the inner conductive ring,
• wherein the electrode assembly is positioned such that conductive fluid flows across the electrode assembly when conductive fluid is received in the fluid lumen, and
• wherein when conductive fluid flows across the electrode assembly and a voltage pulse is applied across the inner conductive ring and the outer conductive ring, current flows across an arcing region between the inner conductive ring and the outer conductive ring to generate at least one of cavitation bubbles and shock waves in the conductive fluid directed out the distal end of the catheter to treat the occlusion.

A catheter for treating an occlusion in a body lumen, the catheter comprising:

• a fluid lumen configured to receive a conductive fluid and direct the conductive fluid out of a distal end of the catheter;
• an aspiration lumen configured to remove debris and the conductive fluid from the body lumen;
• an electrode assembly including (i) an inner conductive cylinder having an uninsulated distal side edge that extends circumferentially around a longitudinal axis of the inner conductive cylinder, and (ii) an outer conductive cylinder spaced apart from the inner conductive cylinder, the outer conductive cylinder having a distal side edge proximate to the distal side edge of the inner conductive cylinder;
• and
• an insulator positioned between the outer conductive cylinder and the inner conductive cylinder,
• wherein the inner conductive cylinder, the outer conductive cylinder, and the insulator are positioned in the fluid lumen such that conductive fluid flows across a portion of the electrode assembly when conductive fluid is received in the fluid lumen, and
• wherein when conductive fluid flows across the electrode assembly and a voltage pulse is applied across the inner conductive cylinder and the outer conductive cylinder, current flows across an arcing region between the inner conductive cylinder and the outer conductive cylinder to generate at least one of cavitation bubbles and shock waves in the conductive fluid directed out the distal end of the catheter to treat the occlusion.