Is It Still Valid to Measure Ejection Fraction When There Are New Deformation Indices to Evaluate Ventricular Function

Abstract

An echocardiographic study helps in the assessment of systolic and diastolic left ventricular function due to potential clinical implications over the treatment and the prognosis of different heart diseases. Systolic function depends on three factors: the left ventricular (LV) function, arterial coupling (ventriculoarterial coupling) and blood volume. In the particular case of the left ventricular function, this is determined by the preload, afterload, contractility, heart rate, ventricular geometry and synergy of contraction. The interaction of these factors determines the shortening of longitudinal and circumferential fibers, with the consequent thickness of the ventricular wall and the expulsion of systolic volume (SV). A 14% of fiber shortening produces approximately a 40% of ventricular wall thickness. (1) Therefore, parietal thickness and the reduction of ventricular volume are inversely related; the greater the thickness, the lesser the end-systolic volume with greater SV and vice versa. Several indexes related to shortening (Tissue Doppler Imaging, strain rate) may be altered in presence of normal ejection fraction (Ef). However, all these indexes are affected by load conditions and ventricular geometry besides contractility. (2, 3)