Colour doppler technique and heart catheterization for haemodynamic evaluation of a ventricular septal defect - Case report

The present case report shows echocardiographic methods used in investigation of a ventricular septal defect. Clinical examination as well as echocardiography were performed at rest and after exercise. The defect of the interventricular septum was clearly visible with the b-mode technique. Additionally colour-coded echocardiography and conventional Doppler technique (PW-/CW-Doppler) revealed informations about the haemodynamics of this defect. The volume of the pathological blood flow (3.3 L/min.) was calculated by the ,,Velocity Time Integral" (using the ,,Vena contracta" method as described elsewhere). The regurgitated volume of blood was also evaluated by comparing right and left ventricular stroke volume. The results of both methods showed a good conformity. A low grade increase in cardiac blood pressure and partial oxygen pressure was measured in the right ventricle by heart catheterisation. The study shows that analysing haemodynamics of a VSD in horses is possible by using colour-coded echocardiography only.