Colour Flow And Doppler Assessment Of Ventricular Septal Defect

Abstract

One hundred and eightyfive patients with isolated ventricular septal defect were studied by colour flow Doppler echocardiography and additionally 52 ofthese patients underwent angiography. The purpose was to evaluate the capability of echocardiography to determine the size and location ofventncular septal defect and to estimate intracardiac pressures. Colour flow Doppler imaging showed that in 11 of52 patients, (21.1 per cent) the site of ventricular septal defect was incorrectly identified when compared to angiography. Subcristal ventricular septal defects were diagnosed on short axis left parasternal view by nothing a colour flow disturbance close to the tricuspid valve. Using this criterion supracristal ventricular septal defects were misdiagnosed as paramembranous in 7 of52 (13.5 per cent) patients while 3 posterior ventricular septal defects were wrongly diagnosed as paramembranous. In one patient additional muscular defects were missed. Review ofechocardiograms ofpatients with supracristal defects .howed that in short axis left parasternal plane, flow disturbance was present close to ricuspid valve as well as underneath the pulmonary valve with an interposed, tissue ‘4 hich may be the prolapsed aortic valve. The Doppler pressure gradient at ventricular .eptal defect was inversely linearly related to the peak systolic pulmonary arterial pressure r O.84). It was further noted that end diastolic pulmonary arterial pressure obtained At cardiac catheterization was linearly related to cardiac catheterization derived nulmonary vascular resistance (r 0.79). Diastolic pulmonary arterial pressure can be neasured by Doppler technique, since in patients with pulmonary arterial hypertension, ulmonary arterial regurgitation is often present so that estimates ofpulmonary vascular - istance would be possible by Doppler technique.