. . . "The position of the movable electrodes 18, 118 may be adjusted to optimize detection of atrial EGM signals emanating from near the S-A node or the fat pads in the triangle of Koch as described in the above-incorporated '356 patent or other areas of the atrial wall or the SVC 106 that the lead outer sheath 14 bears against to detect desired signals or apply electrical stimulation to." .