The implantable cardiac treatment system of the present invention is capable of choosing the most appropriate electrode vector to sense within a particular patient. Also included is a modulator for receiving the Fourier image. The slackened portion is accommodated in a groove portion arranged at the wiring surface of the connector portion in order to minimize the possibility of damaging the wire improving reliability of the connection between the terminal pin and the coil. During the fabrication of each chamber half, the interior spherical surface is completed first and then the outer spherical surface.