Catheter and Method for Focal Cardiac Ablation by Irreversible Electroporation

A catheter for focal cardiac ablation by irreversible electroporation, the catheter comprising:

• a flexible catheter body extending from a proximal end to a distal end, the catheter body forming a lumen extending from the proximal end to the distal end, the catheter body defining a longitudinal axis;
• a plurality of tines disposed at the distal end of the catheter body, the plurality of tines formed of an electrically conductive material and configured to deploy from the lumen at the distal end of the catheter body, each tine of the plurality of tines configured to self-bias from a linear configuration within the lumen to a curved configuration when deployed from the lumen;
• a flexible shaft formed of an electrically conductive material, the shaft mechanically and electrically coupled to the plurality of tines and extending through the lumen from the proximal end of the catheter body, the shaft configured to deploy the tines from the lumen when the shaft is moved toward the distal end of the catheter body;
• a return electrode configured to deploy from the catheter body at the distal end of the catheter body and to form a loop extending from the catheter body;
• and
• an electrical conductor electrically coupled to the return electrode, the electrical conductor extending through the catheter body from the proximal end of the catheter body.

A method for focal cardiac ablation by irreversible electroporation, the method comprising:

• inserting a distal end of a catheter into a heart and adjacent to tissue containing cells to be ablated, the catheter including a flexible catheter body and a plurality of electrically conductive tines configured to deploy from a lumen at the distal end of the catheter body;
• moving a shaft extending through the lumen toward the distal end to deploy the plurality of electrically conductive tines from the lumen and into the tissue containing the cells to be ablated, each tine of the plurality of electrically conductive tines self-biasing from a linear configuration within the lumen to a curved configuration when deployed into the tissue;
• applying a series of voltage pulses between the plurality of electrically conductive tines and a return electrode disposed on an outer surface of the catheter body and spaced apart from the distal end of the catheter body, the voltage pulses forming an electric field causing irreversible electroporation of the cells to be ablated;
• moving the shaft extending through the lumen toward a proximal end of the catheter body to retract the tines into the lumen;
• and
• withdrawing the distal end of the catheter from the heart.