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Figure 1 Method of pattern determination in representative electrocardiogram complexes of lead V₃. The two horizontal lines represent the Q–Q line and the line parallel to the Q–Q line at the level of the J point, respectively. The arrow marks the J point; the short vertical line marks the point 60 ms after the J point; the oblique line connects the J point with the above point (see text). (A) Female pattern: the J point is at the level of the Q–Q line, and the ST angle is 19°. (B) Male pattern: the J point is >0.1 mV above the Q–Q line, and the ST angle is 36°.(C) Variant of the male pattern in which the T-wave ascends at the J point; the J point is >0.1 mV above the Q–Q line, and the angle between the line parallel to the Q–Q line at the level of the J point and the ascent of the T-wave is 29°. (D) Indeterminate pattern: the J point is >0.1 mV above the Q–Q line, and the ST angle is 15°.