女性66岁,有高血压冠心病、糖尿病史、终末期肾病。1周前因缺血性心脏病、冠脉放支架。病人进急诊室时,诉有严重胸骨下方疼痛呼吸困难,神情恍惚约1h之久。体检:生命征正常。无颈静脉怒张,肺部清,心律正常无杂音,无奔马律,无摩擦音(图1)。问:心电图的最佳诊断?左束支传导阻滞(LB 66-year-old female, with coronary heart disease, history of diabetes, end-stage renal disease. A week ago because of ischemic heart disease, coronary stent. When the patient into the emergency room, complained of severe pain in the bottom of the chest pain, trance about 1h. Physical examination: vital signs normal. No jugular vein distention, clear lungs, normal heart rhythm noise, no gallop, no friction sound (Figure 1). Q: The best diagnosis of ECG? Left bundle branch block (LB