[ECG mapping studies for optimal electrode placement for the detection of stress-induced changes in R-amplitude in the diagnosis of chronic ischemic heart disease].

: The evidence on the clinical relevance of the behaviour of the R-amplitude under load for the non-invasive diagnosis of the chronic ischaemic heart disease is contradictory in literature. One of the causes for the variable estimation is possibly to be found in the different localization of the lead electrodes. With the help of the ECG mapping using 30 electrodes at the anterior thoracic wall 15 males were examined with typical syndrome of angina pectoris and a clearly pathological reaction of the ST-distance in a preceding usual bicycle ergometry. The ECG mapping was carried out before, during and after an ergometer load in lying position with 50 Watt. The most frequent pathological reactions of the R-amplitude were found below the chest wall electrodes V4, V5 and V6 after Wilson. The estimation of the valency of this first observation must be performed in further examinations.