Description

The long axis parasternal view is one of the most widely used in neonatal intensive care. A lot of useful information may be derived from it. This includes shortening fraction (as a guide for left ventricular contractility), left atrial to aortic root ratio (to assess PDA related volume loading), ventricular filling, the diameter of the aortic and pulmonary roots (used to calculate outputs), the tricuspid valve regurgitant jet if present (used to calculate right sided pressure), in addition to visual inspection of the thickness of the ventricular walls including the septum. This view is ideal for the examination of the interventricular septum for defects, the presence of aortic and mitral valve regurgitation, and the origins of the great arteries. The long axis parasternal window is situated at the left sternal border and the lower to middle third section of the sternum. The probe is positioned straight down with the probe marker pointing towards the right shoulder. Rotate the probe anti-clockwise (or clockwise) to catch the full length of the left ventricle and avoid shortening the left ventricle. The aorta, left atrium, and the left ventricular cavity all the way to the apex should be visible. Colour Doppler interrogation of the aorta and the mitral valve is carried out to assess valve competency. In addition, a colour Doppler interrogation of the interventricular septum is necessary to look for ventricular septal defects. This is also carried out in the apical 4 chamber and parasternal short axis views.