Actively anchored electrode for electrode catheters

Claim 1

An actively anchored electrode catheter comprising: a protective insulating tubular sheath having an enlarged end portion; at least one spiral wound stimulation signal conductor accommodated internally of the sheath; a spiraled anchor point ending in a tip, positioned at and projecting from a distal end of the tubular sheath a rotation control means, connected stably to the protective tubular sheath in a position coinciding with the enlarged end portion of the sheath and isolated electrically from the spiral wound conductor, for rotating the spiraled anchor point causing the spiraled anchor point to penetrate a cardiac muscle thereby anchoring the electrode catheter; a stimulation head disposed coaxially with the sheath and connected to the spiral wound conductor, at least partly encircled by the spiraled anchor point, of which an exposed surface is disposed in alignment at least with the tip of the point in a non-operative configuration of the catheter; conductive elastic means interposed between the stimulation head and the spiral wound conductor for allowing a measured retraction of the head into the sheath as the spiraled anchor point is made to penetrate the cardiac muscle, in such a way that the contact induced between the head and the surface of the cardiac muscle can be maintained constant independently of the penetrating movement of the point.