Echocardiography Textbook


The time at which the maximum gradient of the transmitral diastolic flow is halved can be used to measure Mitral Valve Area (MVA). This is the so-called pressure half-time (T ½) or PHТ (Pressure Half-time).

Empirically, if the Mitral Valve Area (MVA) is 1 cm2, then the Pressure Half-Time (PHT) is 220 s. From here we can find the MVA:



MVA - Mitral Valve Area. PHT - Pressure Half-Time


Assessment of mitral stenosis by the Mitral Valve Area (MVA):

  • Mild > 1.5 cm2
  • Moderate 1.0 - 1.5 cm2
  • Severe < 1.0 cm2


Apical 4 Chamber View. Sample Volume position for examining the transmitral diastolic flow. Simulation By Echocardiography Online Simulator


Apical 4 Chamber View. CW doppler. Transmitral diastolic flow. Measurement of the Pressure Half-Time (PHT). Simulation By Echocardiography Online Simulator



ASE Guideline - Echocardiographic Assessment of Valve Stenosis


How to Simulate Assessment degree of Mitral Stenosis by PHT? >>>