Right Ventricular Outflow Tract Systolic Excursion and Fractional Shortening: Can These Echocardiographic Parameters be used for Assessment of Right Ventricular Function?

Abstract

Right ventricle is the cardiac chamber that receives the blood from right atrium and pumps it to the lungs through pulmonary artery. Unlike left ventricle, right ventricle structure is complex. It can be divided into three parts: the inlet containing tricuspid valve, apex which is the most trabeculated part and outlet (right ventricular outflow tract) which is the smooth part that connects the RV to the pulmonary valve and pulmonary trunk. Traditionally right ventricular function assessment was ignored because of its complex structure and the lack of awareness of its clinical importance. Right ventricle was found to be very important determinant of prognosis in patients with heart failure, pulmonary hypertension, pulmonary embolism and congenital heart diseases. Echocardiography is the main tool used for assessment of the heart including right ventricular function. The current used parameters used for right ventricular function assessment mainly assess its inlet part ignoring its outlet part. Only few small studies had studied right ventricular outflow tract function and its contribution to the overall RV function but still there is a controversy. We have studied the role of right ventricular outflow tract fractional shortening and right ventricular outflow tract systolic excursion in assessment of RV function. RVOT FS is defined as the percentage of maximum decrease of RVOT diameter during systole relative to RVOT diameter at end diastole and RVOT SE is defined as distance of excursion of endocardium of RVOT anterior wall from end diastole to end systole.