心電図の(a)V(L)誘導の陰性T波に関する研究

The negative T wave in lead aVL is one of the electrocardiographic features of left ventricular hypertrophy or myocardial infarction, associated with negative T wave in lead v(5), v(6) and Ⅰ. Whereas the significance of isolated negative TaVL, not associated with other abnormal negative T wave, is of much controversial. The electrocardiographic and vectorcardiographic changes of 146 cases were studied for appreciation of negative TaVL, whose TaVL were negative in 115 cases with or without negative ST, Tv(5), v(6), positive in 23 cases, and flat in 7 cases. The electrocardiographic diagnosis of left ventricular hypertrophy was found in 50 cases, of old myocardial infarction, in 24 cases, and the remaining were admitted to R(Ⅰ)>R(Ⅲ) group (41 cases) and to R(Ⅰ)R(Ⅲ) group, if associated with isolated negative TaVL, T(Ⅲ)>T(Ⅰ) and TV(Ⅰ)/TV(5)≥0.74, the same displacement as in left ventricular hypertrophy and myocardial infarction was found, suggesting ischaemic change of lateral wall. In R(Ⅰ)T(Ⅰ) and TV(Ⅰ)/TV(5)≥0.56, the spatial T loop was in anterior position, but with no pathological meaning. Negative TaVL associated with R(Ⅰ)>R(Ⅲ), T(Ⅲ)>T(Ⅰ) and TV(Ⅰ)/TV(5)<0.74 or R(Ⅰ)T(Ⅰ) and TV(Ⅰ)/TV(5)<0.56, was sign of inferior, posteroinferior, posterior or normal position of spatial T loop, and abnormal T loop (spatial length/width≤2.6, abnormal speed of inscription, irregular shape, wide spatial QRS-T angle) was found more frequent in R(Ⅰ)>R(Ⅲ) group (66.7%) than in R(Ⅰ)