A cardiac electrode arrangement has one or several heart electrodes arranged on the exterior surface of a heart or attached to the heart from the outside and/or arranged with a pole in the cardiac tissue. The electrodes, which can be fixed in the operating position by an anchor, run to an implanted heart pacemaker. For positioning and affixing the anchor, a tool is used that is designed as a rod or stylet and acts on an attachment site of the anchor, whereby the anchor can be pushed into or through the myocardium. The anchor is, at the same time, attached to a tension element or thread, over which the electrode, which has an inner guide channel that accommodates the tension element or thread, can be moved in a fitted and controlled manner. In the operating position, the electrode can be connected to the tension element or thread located in the guide channel.