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Basic Electrocardiography Normal and abnormal ECG patterns - Part 2

Quan sát (dòng liên tục) tích cực và một phần tiêu cực (dòng chấm) mỗi chì. (C) vector khác nhau (1-6) sản xuất dự đoán khác nhau theo vị trí của họ. Ví dụ, vector 1 có một dự báo tích cực dẫn tôi, lưởng tướng II và tiêu cực trong III trong khi vector 3 là lưởng tướng trong tôi, | Figure 11 A Einthoven s triangle. B Einthoven s triangle superimposed on a human thorax. Observe the positive continuous line and negative dotted line part of each lead. C Different vectors from 1 to 6 produce different projections according to their location. For example vector 1 has a positive projection in lead I diphasic in II and negative in III while vector 3 is diphasic in I positive in II and III. For example vector 1 has a positive deflection in I diphasic in II and negative in III and vector 3 is diphasic in 1 and positive in II and III. In both cases II I III. A vector located to 60 originates a positive deflection in I II and III but also with II I III. Figure 13 A Sites where the explorer electrodes are located in unipolar precordial leads and B sites where positive poles of the six precordial leads are located. Electrophysiological principles 13 Figure 14Positive an d negative hemifields of the six frontalplane leads and the horizontal plane leads depanding on the magnitude and direct ion of the different vectors which represent the corresponding loops positive and negative deflections with different voltes are originated see the text . the same manner drawing lines that are pgrpendicular to the corresponding lead passing through the centre of the heart Figure 14 . Inall 4he cases the negative hemifields are opposed to the pasitive ones. A loop of p QRS or T or its maximum vector located in the positive or the negative hemifidd or on the borderlrnpbetween both hemifields in any of the 12 leads gives rise respectively to a positive deflection negative deflection or isodiphasic deflection of p QRS or T waves in that given lead. A isodiphasic deflection has a maximum vector but may have a different morphology it can bepositive-negative or negative-positive accordingti the direction of the loo- rotation tpat repcesente the it etlttiiait the stimulusfollows gfgure4 . The degree o.poeifivifyor no sivity .e.ends-o two .actors tie- cnagnihode and the .