Use and Limitations of E/e' to Assess Left Ventricular Filling Pressure by Echocardiography

Abstract

Measurement of left ventricular (LV) filling pressure is useful in decision making and prediction of outcomes in various cardiovascular diseases. Invasive cardiac catheterization has been the gold standard in LV filling pressure measurement, but carries the risk of complications and has a similar predictive value for clinical outcomes compared with non-invasive LV filling pressure estimation by echocardiography. A variety of echocardiographic measurement methods have been suggested to estimate LV filling pressure. The most frequently used method for this purpose is the ratio between early mitral inflow velocity and mitral annular early diastolic velocity (E/e'), which has become central in the guidelines for diastolic evaluation. This review will discuss the use the E/e' ratio in prediction of LV filling pressure and its potential pitfalls.

Keywords: Doppler echocardiography; Echocardiography; Left ventricular filling pressure.

Fig. 1

Diagram of intracardiac pressures according to the cardiac cycle. During diastole, pressure gradient between left ventricle and left atrium derives blood flow.

Fig. 2

Mitral inflow velocities obtained by pulsed wave Doppler technique and their schematic diagram. Peak mitral inflow velocity during early diastole (E wave), peak mitral inflow velocity at atrial contraction (A wave), mitral deceleration time (DT), duration of A wave (Adur), and interval between aortic valve closure (Ac) and start of mitral inflow (IVRT) are labelled. IVRT: isovolumic relaxation time.

Fig. 3

Mitral annular velocities obtained by tissue Doppler echocardiography. s' velocity: systolic velocity, e' velocity: early diastolic velocity, a' velocity: late diastolic velocity, IVCT: isovolumic contraction time, ET: ejection time, IVRT: isovolumic relaxation time.