本文报道3例伴有左房逆传活动的房内传导障碍,(略为 IACD—LARA),本病国内尚少报道,其心电图诊断标准为 P≥120ms,PⅡ、Ⅲ、avF 显正负双向。一些作者尚提出正交心电图及心电向量图的诊断标准。此种传导障碍时,左房除极顺序变为激动先抵达右房底部尔后向上除极左房。IACD—LARA 多伴有左房肥大及房颤或房扑。 This article reports 3 cases with left atrial retrograde conduction of intra-atrial conduction disorders, (slightly IACD-LARA), the disease is still rarely reported in the country, the ECG diagnostic criteria for P ≥ 120ms, P Ⅱ, Ⅲ, avF positive and negative bidirectional. Some authors still proposed orthogonal ECG and ECG vector chart diagnostic criteria. Such conduction disorder, the left atrium depolarization sequence into the first arrived at the right atrium after the top of the house after the top of the diaphragm in addition to a very left atrial. IACD-LARA often accompanied by left atrial hypertrophy and atrial fibrillation or atrial flutter.