Pulsed Doppler echocardiographic evaluation of the shunt flow in ventricular septal defect.

Abstract

Pulsed Doppler echocardiography (PDE) was performed on 67 patients with ventricular septal defect (VSD) using an ATL 500A pulsed Doppler system. The subjects were divided into 3 groups according to their clinical diagnosis. Group 1 consisted of 39 patients with isolated VSD and 15 with associated cardiac malformations. The VSD jet was recognized through the interventricular septum (IVS) and was followed into the right ventricular cavity. These PDE findings were obtained in 52 of the 54 Group 1 cases. There was a false negative PDE diagnosis in 2 patients who showed a bidirectional communication at the ventricular level. Thus the sensitivity of PDE to this lesion was 94%. The disturbed systolic flow within the IVS was mainly detected below the aortic root, near the septal tricuspid leaflet (STL) and between them. In 23 patients, regurgitant flow was recognized only at the defect. In 12 of the 54 cases, PDE revealed the VSD jet from the defect to the distal right ventricular outflow tract (RVOT) toward the pulmonary valve. These PDE findings were frequently obtained from patients with supracristal VSD; 8 of the 12 had angiographically and/or surgically proven supracristal VSD, 3 had clinical signs and echocardiographic findings that implied this type of defect and the remaining one was a type II VSD (Kirklin) with hyperkinetic pulmonary hypertension. Six patients showed a systolic flutter of the tricuspid valve and/or systolic anterior movement on M-mode echocardiogram. Five of them were shown to have aneurysms of the membranous septum and another one had a type III VSD at surgery. A disturbed systolic flow pattern was obtained when the sample volume was placed on the fluttered valve and also within the aneurysmal sac. Group 2 was composed of 3 cases with Eisenmenger's complex and 7 with tetralogy of Fallot. PDE revealed no disturbed flow at the defect. In 2 patients with Eisenmenger's complex, systolic turbulence was seen within the left ventricular outflow tract, while in 8 cases, an early diastolic right-to-left communication was demonstrated as a laminar reversed flow, a finding consistent with an abrupt posterior movement of the remnant of the tricuspid leaflet into the left ventricle in one of this group. Group 3 was comprised of 3 cases with left ventricular-right atrial communication. The regurgitant flow was detected as a systolic wide band pattern through the IVS near the STL and was followed into the right atrium. No patients in this group showed clinical signs or echocardiographic findings of this lesion. Based upon our findings, PDE was thought to be useful for noninvasive identification of various types of VSD.