EchocardiographyExercise StressMiscExercise Stress
Duke Treadmill ScoreMaximum Predicted Heart Rate (DOB)Mets & VO2 (Treadmill)
Maximum Predicted Heart Rate (Age)Max. Predicted Heart Rate AchievedRate Pressure Product

dP/dt Isovolumic Phase Index of RV Contractility


Time ms (1-2 m/s TR)

dP/dt mmHg/s



The RV contractility dP/dt can be estimated by using time interval between 1 and 2 m/sec on TR velocity CW spectrum during isovolumetric contraction i.e. before pulmonic valve opens when there is no significant change in RA pressure.

Although the time from 1 to 2 m/s is most commonly used, the best correlation between echocardiographic and invasive measures was found by using the time for the TR velocity to increase from 0.5 to 2 m/s. In this case the numerator for the calculation is 15 mmHg.

dP/dt =

Variable Definition
T Time (1 to 2 m/sec TR) (seconds, s)
dP/dt dP/dt (mmHg/s)
Likely Abnormal <400 mmHg/s


Rudski LG, et al. Guidelines for the echocardiographic assessment of the right heart in adults: a report from the American Society of Echocardiography. J Am Soc Echocardiogr. 2010 Jul;23(7):700.
Oh JK, et al. The Echo Manual. 2nd ed. p. 70, 1999.


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