(来学网)一度房室传导阻滞时的心电图改变是
  • A.
    (来学网)PR间期<0.21s
  • B.
    (来学网)PR间期逐渐延长
  • C.
    (来学网)P波增宽≥0.12s
  • D.
    (来学网)QRS增宽≥0.12s
  • E.
    (来学网)PR间期≥0.21s