a bioelectric interface is disclosed which provides three einthoven triangle equivalent lead forming electrodes positioned on a subject &# 39 ; s chest so as to provide a wilson common terminal voltage essentially equivalent to that provided by an einthoven triangle formed using leads positioned conventionally on a subject &# 39 ; s limbs . wilson common terminal forming resistors can be of fixed values or variable to allow adjustment of a produced wilson common terminal voltage . additional precordial electrodes are also typiclaly present . electrodes can consist of single elements or groups of electrode elements , and are present in locational regions of the bioelectric interface which allow a single size system to fit to patients with various sized bodies . the electrodes can be of various physical shapes to allow not only direct signal measurement , but also to allow monitoring of high frequency content of signals and to allow enhanced resolution of a region from which measured signals originate . in addition , the present invention bioelectric interface is preferably held in place on a subject &# 39 ; s chest with hydropolymer , and need not be removed to allow cardio - pulmonary - resuscitation , defibrillation , cardiac pacing , electro surgery , electro ablation or impedance cardiography to be performed , and it serves to preserve the relative spatial integrity of the positioning of the electrodes present during use . the presence of a number of spatially separated electrocardiogram system electrodes facilitates reduction of the adverse electrode edge effects when defibrillation is performed through the bioelectric interface .