Electrode assemblies and associated fixation members for implantable medical devices

摘要

A fixation member of an electrode assembly for an implantable medical device includes a tissue engaging portion extending along a circular path, between a piercing distal tip thereof and a fixed end of the member. The circular path extends around a longitudinal axis of the assembly. A helical structure of the assembly, which includes an electrode surface formed thereon and a piercing distal tip, also extends around the longitudinal axis and is located within a perimeter of the circular path. The tissue engaging portion of the fixation member extends from the distal tip thereof in a direction along the circular path that is the same as that in which the helical structure extends from the distal tip thereof. The electrode assembly may include a pair of the fixation members, wherein each tissue engaging portion may extend approximately one half turn along the circular path.

主权项

1. An electrode assembly for an implantable medical device, the assembly comprising a longitudinal axis, a helical structure coupled to a distal portion of the device and extending distally from the distal portion and around the longitudinal axis, a first electrode surface formed on the helical structure, and a second electrode surface electrically isolated from the first electrode surface, the helical structure including a piercing distal tip located adjacent to the first electrode surface; and an improvement to the assembly comprising: a pair of fixation members, wherein each fixation member of the pair comprises:
a fixed end coupled to the distal portion of the device; and a tissue engaging portion terminated by a piercing distal tip, each tissue engaging portion extending from the corresponding distal tip to the corresponding fixed end along a circular path, the helical structure being located within a perimeter of the circular path; and wherein both tissue engaging portions extend from the corresponding piercing distal tip thereof in a direction along the circular path that is the same as that in which the helical structure extends from the piercing distal tip thereof, either clockwise or counter-clockwise.