LV Shortening fraction
Description
Shortening fraction characterises left ventricular function and volume loading using m-mode methods from either a long parasternal axis or short axis view of the left ventricle. It is calculated by measuring left ventricular end diastolic diameter (LVEDD) and left ventricular end systolic diameter (LVESD) using M-mode echo and applying the following formula: SF%= (LVEDD-LVESD) x100 / (LVEDD). Normal neonatal values for FS% are = 28 to 40%. In the setting of a PDA, LVEDD increased with increased LV volume loading and as a result, shortening fraction is often increased in the presence of a PDA.Doppler
Diagram
The cursor is placed through the left ventricle perpendicular to the intraventricular septum at the level of the mitral valve tips. M-Mode is used to measure the widest diameter of the LV during diastole and the narrowest diameter in systole.
Diagram
M-Mode is used to measure the widest diameter of the LV during diastole (LVEDD) and the narrowest diameter during systole (LVESD) to calculate SF. The cursor should be perpendicular to the intraventricular septum at the level of the mitral valve tips.