EchocardiographyExercise StressMiscEchocardiography
Aortic Valve Velocity RatioLV EF (Modified Quinones Equation)Myocardial Performance Index (RV)
AVA (Continuity Equation VTI)LV EF (Simplified Quinones Equation)PCWP by E/Ea (Nagueh Formula)
AVA (Continuity Equation VMax)LV Fractional ShorteningPISA (Mitral regurgitation)
dP/dt (LV contractility)LV Mass and LV Mass IndexPISA (Mitral stenosis)
dP/dt (RV contractility)Mitral valve area (PHT)Qp/Qs
Left atrial pressure (MR)Mitral Valvuloplasty Score (MGH)RVSP (TR)
LA Volume (Biplane Method)Modified Bernoulli EquationStroke Volume, Cardiac Output
LV EF (Dumesnil Method)Myocardial Performance Index (LV)

PCWP by E/Ea (Nagueh Formula)


e' (lateral) cm/s
e' (septal) cm/s

e' (average) cm/s



e', the early diastolic velocity of mitral annulus as obtained by tissue Doppler imaging (TDI) of the septal and lateral sides of the mitral annulus behaves as a pre-load-independent index of LV relaxation. Mitral inflow E velocity as obtained by pulsed-wave (PW) Doppler when corrected for the influence of relaxation by using E/e' ratio correlates well to the mean pulmonary capillary wedge pressure (PCWP) as obtained by simultaneous catheter measurements.

It is preferable to use the average e' velocity obtained from the septal and lateral sides of the mitral annulus for the prediction of LV filling pressures. Because septal e' is usually lower than lateral e' velocity, the E/e’ ratio using septal signals is usually higher than the ratio derived by lateral e', and different cutoff values should be applied on the basis of LV EF, as well as e' location.

E/e' ratio < 8 is usually associated with normal LV filling pressures (PCWP < 15 mmHg), while a ratio > 15 is associated with increased filling pressures (PCWP > 15mmHg). Between 8 and 15, there is a gray zone with overlapping of values for filling pressures.

e' = (e'lateral + e'septal) / 2
PCWP = 1.24 * (E/e') + 1.9

Variable Definition
E Mitral inflow E velocity (m/s or cm/s)
e' (lateral) Early diastolic velocity of lateral mitral annulus (m/s or cm/s)
e' (septal) Early diastolic velocity of medial mitral annulus (m/s or cm/s)
e' Average of the lateral and septal e' values.
E/e' E/Ea ratio
PCWP Mean pulmonary capillary wedge pressure (mmHg)


Nagueh SF, Middleton KJ, Kopelen HA, Zoghbi WA, Quinones MA. Doppler tissue imaging: a noninvasive technique for evaluation of left ventricular relaxation and estimation of filling pressures. J Am Coll Cardiol 1997;30:1527-1533


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