[Mapping of the cardiac electric activity. Applications to experimental surgery]

The results reported by French and other groups of workers have shown that peroperative epicardial mapping is a valuable technique for locating the accessory pathway in the Wolff-Parkinson-White syndrome and also in the surgical treatment of certain forms of chronic ventricular tachycardia. The aim of this study was to develop a completely automatic method of mapping potentials recorded at many points during the same systole. A system of acquisition and automatic treatment of 256 cardiac potentials called SATAPEC was constructed at the University of Caen. The system comprises specialized recorders, a multiplexing system on 256 leads with analogical-digital conversion and a PDP 11-23 mini computer. The results presented are based on the location of the His bundle and the right bundle branch in the dog from recordings of the H potential. The recording device with 240 (20 x 12) measuring points is a silk net on which 50 micrometers diameter silver wires are attached. The wires are insulated except at their tips and are separated one from another by a distance of 2 mm. After infundibulotomy the recording device was placed over the interventricular or right interatrial septum. The 240 unipolar electrograms were recorded during a single systole. The programmes which have been developed automatically produce maps of the amplitude of the H potential. The computer detects the presence or absence of a H potential on each electrogram and then displays on a cathode ray tube points of variable size indicating the locations of the electrodes which have recorded a H potential.(ABSTRACT TRUNCATED AT 250 WORDS)