Left Ventricular Global Strain for Estimating Relaxation and Filling Pressure　- A Multicenter Study

Area of Science:

• Cardiology
• Echocardiography
• Diastology

Background:

• Speckle-tracking echocardiography (STE) parameters may offer superior correlation with left ventricular (LV) relaxation and filling pressures compared to tissue Doppler imaging.
• The relative utility of STE-derived strain versus strain rate, and longitudinal versus circumferential deformation, for assessing LV relaxation and filling pressure remains unclear.

Purpose of the Study:

• To compare the correlation of various STE- and tissue Doppler-derived parameters with LV pressure decay (τ) and mean diastolic pressure (MDP).
• To determine the most effective echocardiographic marker for estimating LV filling pressure.

Main Methods:

• A prospective multicenter study involving 77 patients.
• Comparison of correlations between tissue Doppler parameters (e.g., e´, E/e´) and STE parameters (e.g., longitudinal strain [LS]) with τ and LV mean diastolic pressure (MDP).
• Receiver-operating characteristic (ROC) analysis to evaluate the diagnostic performance of E/LS and E/e´ for elevated LVMDP.

Main Results:

• Early diastolic mitral annular velocity (e´) showed a weak correlation with τ (r=-0.32).
• Peak longitudinal strain (LS) demonstrated the strongest correlation among STE parameters with τ (r=-0.45).
• The ratio of early diastolic inflow velocity to longitudinal strain (E/LS) correlated strongly with LVMDP (r=0.70), outperforming the E/e´ ratio (r=0.50).
• E/LS exhibited a significantly better correlation with LVMDP than E/e´ (P<0.01) and showed the largest area under the curve in ROC analysis for distinguishing elevated LVMDP (0.86).

Conclusions:

• STE-derived longitudinal parameters, particularly LS, correlate well with LV relaxation and filling pressures.
• The E/LS ratio appears to be a more accurate and effective parameter than E/e´ for estimating LV filling pressure.