Three-dimensional frontal

Repolarization of the ventricle leads to the T wave. The T wave usually goes in the same direction as the QRS complex. The normal axis of the ECG is 30 degrees (above the horizontal) to 4-110 degrees (away from the horizontal) (Fig. 11-5). The six frontal plane (A) and the six horizontal plane (B) leads provide a three-dimensional representation of cardiac electrical activity. 

FIGURE 11-5. The six frontal plane (A) and six horizontal plane (6) leads provide a three-dimensional representation of cardiac electrical activity. (Redrawn from ref. 7 with permission.)... 

Fig. 6. A photograph of a three-dimensional CT. scan of a twenty-eight-week old fetal skull, frontal orientation. Notice the triangular defect between the hemimandibles (arrow).

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