(来学网)M型超声心动图,正常成人主动脉瓣开放幅度应不小于()
  • A.
    (来学网)10mm
  • B.
    (来学网)30mm
  • C.
    (来学网)18mm
  • D.
    (来学网)20mm
  • E.
    (来学网)16mm