Methods for Assessing Left Ventricular Diastolic Distensibility

Abstract

The major property of the myocardium that determines left ventricular (LV) filling is its distensibility. The simplest measure for its assessment is the LV end-diastolic pressure–volume ratio, although it can vary within a wide range and is highly dependent on inflow and resistance boundary conditions, making distensibility difficult to assess. Here, we consider six calculated indices of LV diastolic stiffness, most of which are based on Hooke’s law, comparing their stability, variation, and correlation coefficients with different hemodynamic parameters. The diastolic stiffness index No. 4 proved to be the only measure that takes into account an increase in LV stiffness over diastole. It shows a weak dependence on LV ejection fraction, heart rate, and other parameters of LV hemodynamics, and hence can be used to assess LV diastolic distensibility in various cardiac pathologies.