05341807 is referenced by 540 patents and cites 17 patents.

A multi-electrode cardiac catheter has pairs of electrodes connected to sensing circuitry to produce a differential signal. The sensing output is sharply defined and self-normalizing. Preferably a catheter ablation tip electrode is an electrode of one pair, and the differential signal becomes non-zero when the tip contacts surrounding tissue. The shape of the differential signal provides information on the degree of electrode contact, as well as on the on the amount of locally-sensed tissue impedance change. The signal may be used as a trigger enable signal for a cardiac ablation catheter, and the applied level of RF power may be controlled based on the indicated degree of electrode contact and value of tissue impedance.

Title
Ablation catheter positioning system
Application Number
7/906529
Publication Number
5341807
Application Date
June 30, 1992
Publication Date
August 30, 1994
Inventor
Paul C Nardella
North Easton
MA, US
Agent
Lahive & Cockfield
Assignee
American Cardiac Ablation Co
MA, US
IPC
A61B 5/04
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