Abstract:Objective To explore the features of F lead on electrocardiogram(ECG) in diagnosing mirror dextrocardia.MethodsIn health checkup, F lead was utilized to collect mirror dextrocardia ECG which was interpreted afterwards.ResultsThirteen cases of mirror dextrocardia were detected (accounting for 0.018%) by lead F. Each wave of lead Ⅰ in mirror dextrocardia was inverted, that was, P, QRS and T waves were inverted; The forms of waves in leads F2(Ⅱ) and F6 (Ⅲ ), and leads F3 (aVR) and F1 (aVL) were interchanged; The forms of waves in leads V3R and V5R were similar to leads V3 and V5 at normal time, which represented the left ventricular waves.The leads V1 and V2 represented the right ventricular waves.ConclusionThe characteristics of the mirror dextrocardia indicated that: leads F1 (aVL) and F2 (Ⅰ) of P waves displayed mirroring QRS waves; The main waves of P-QRS-T complex in leads F1 (aVL), F2 (Ⅰ), F3 (-aVR) and F4 (Ⅱ) were downward, with rS type and increasing trend in the amplitude of R wave; The lead F5 (aVF) of QRS wave stayed unchanged; The chest leads V1~V6 was in the shape of rS type, with progressively decrease in the amplitude of R wave and relatively increase in the depth of S wave and in the ratio of R/S; The R wave of lead V1 was high and sharp; There were usually accompanied with other ECG changes.