The distribution of cardiac potentials around the chest in one hundred and three normal men.

Chest leads farther right to V, and farther left to V6 have been suggested, and are increasingly used, for diagnosis of right ventricular or posterior wall lesions. Normal standards are provided for the regional distribution of seven arbitrarily defined patterns and amplitudes of main deflections , in five positional groups, in 15 leads around the chest, resulting in statistical evaluation of 600 electrocardiographic items. In general, the results favor a much more conservative interpretation than has been noted in the past. Some implications to electrocardiographic theory are discussed. ALTHOUGH MULTIPLE precordial leads have been generally introduced in clinical routine electrocardiography, a normal sample adequate in size for normal standards of the leads V1 to V6 has not been available until very recently (Sokolow and Friedlander'). For many years Kossmann and Johnston's2 material of only 30 normal subjects was used as a normal reference.3 In the series of 52 cases of Myers and co-workers4 the normality of the heart was shown by autopsy, but no statistical analysis was made; the presentation of their material was of a descriptive character. Even Sokolow and Friedlander's larger sample is not satisfactory because of the heterogeneous character of their group and the failure to differentiate between the electrical heart positions. Dolgin and associates5 investigated the differences between CR, CL, CF and V leads, but the samples were too small to be used for the calculation of normal standards. It has been recognized that in conditions of pronounced clockwise or counterclockwise rotation around the long axis, the six conventional precordial leads V, to V6 are not sufficient to arrive at a definite interpretation. Right lateral leads have been suggested for suspected right ventricular preponderance6-9 and V7, V8 or other left back leads for suspected coronary Grants Division of the United States Public Health Service. 201 insufficiency or infarct of the posterior wall.10'1' In the absence of normal-standard material, the standards for other leads, such as V, or VR for the right lateral leads, and V6, VL or VF for the back leads, are used currently as criteria of normality. In this paper information is provided on the distribution of electrocardiographic patterns around the chest at the level of the heart in 103 normal men. These should have immediate value as a background for clinical interpretation but the results also have a bearing on some theoretic aspects of unipolar electrocardi-ography. METHOD Fifteen leads were taken around the …