Pulmonary Venous Flow Doppler Pattern in Infant Atrial Septal Defect Cases

Rhee, Kyung Shin; Park, Youngshin; Yu, Jeong Jin; Kim, Chang Hwi

Abstract

PURPOSE
Doppler findings of pulmonary venous flow in large atrial septal defect(ASD) has been known to show a contiguous form rather than showing a form with two peaks in a cardiac cycle. The aim of this study was to find out the affecting variables in flow pattern change.
METHODS
The present study was conducted on 16 isolated secondum ASD infants with defect diameters greater than 3 mm(L group), 10 infants with a defect diameter less than 3 mm(S group) and 11 infants with no structural abnormal findings(N group), among infants who visited the Pediatric Department of Soonchunhyang University Hospital and underwent a echocardiographic examination from April 2001 through June 2003. The echocardiographic examination included the midflow ratio of the pulmonary vein, calculated by division(numerator:the minimum velocity between S & D velocities, denominator: the mean value of S & D velocities).
RESULTS
The mean ages of these three groups(L group, S group and N group) were 0.35+/-0.34 years, 0.22+/-0.22 years and 0.45+/-0.27 years, respectively. The midflow ratios were 0.76+/-0.20, 0.54 +/-0.11, 0.53+/-0.11 in groups, and significant difference between L group and the other two groups (P=0.002). The only affecting variable to midflow ratio is the defect area. And there is a significant causal relationship between them(P=0.003).
CONCLUSION
The fact that Doppler findings of the pulmonary venous flow in a large sized atrial septal defect show a contiguous form is thought to be due to the unique hemodynamic characteristics of the ASD. The results of this study showed that such altered pattern ascertained as the defect size became larger.