Right Ventricular Outflow Tract (RVOT) Changes in Children with an Atrial Septal Defect: Focus on RVOT Velocity Time Integral, RVOT Diameter, and RVOT Systolic Excursion.
OBJECTIVE
Aim of the study was to determine the influence of right heart volume overload in children with atrial septal defect (ASD) on right ventricular outflow tract (RVOT) variables.


METHODS
A prospective study was conducted in 115 children (age range: 2 days-18.1 years) with a moderate to large ASD. We determined effects of age, body length (BL), body weight (BW), and body surface area (BSA) on the variables RVOT diameter, RVOT velocity time integral (VTI), and RVOT systolic excursion (SE), and tested the predictive value of published normal values for age, BW, BL, and BSA in our ASD patients.


RESULTS
In our pediatric ASD patients, the age-specific RVOT diameter (z-score: +2.2, 95% CI: 2.0-2.4, P < 0.001) was significantly increased compared to normal values with 54% of our ASD patients having a z-score >2.0. The age-specific RVOT VTI z-score (z-score: +3.6, 95% CI: 3.2-3.9, P < 0.001) was significantly increased compared to normal values with 81% of our ASD patients having a z-score >2.0. The age-specific RVOT SE z-score was not increased but slightly lower compared to normal values (z-score: -0.5, 95% CI: -0.7 to -0.3, P < 0.001) with 3% of our ASD patients having a z-score >2.0 while 12% of the patients had a z-score <-2.


CONCLUSIONS
In our study population, we show the RVOT VTI and diameter to be relevant predictors in identifying an enlarged RVOT size and flow in children with moderate to large ASD.
Division of Pediatric Cardiology, Department of Pediatrics, Medical University Graz, Graz, Austria. martin.koestenberger@medunigraz.at, koestenbergerm@gmx.at.
Martin
M
Koestenberger
Division of Pediatric Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
William
W
Ravekes
Institute for Medical Informatics, Statistics and Documentation, Medical University Graz, Graz, Austria.
Alexander
A
Avian
Division of Pediatric Cardiology, Department of Pediatrics, Medical University Graz, Graz, Austria.
Gernot
G
Grangl
Division of Pediatric Cardiology, Department of Pediatrics, Medical University Graz, Graz, Austria.
Ante
A
Burmas
Division of Neonatology, Department of Pediatrics, Medical University Graz, Graz, Austria.
Wolfgang
W
Raith
Institute of Physiological Chemistry, Centre of Physiological Medicine, Medical University Graz, Graz, Austria.
Gerhard
G
Cvirn
Division of Pediatric Cardiology, Department of Pediatrics, Medical University Graz, Graz, Austria.
Marlene
M
Grillitsch
Division of Pediatric Cardiology, Department of Pediatrics, Medical University Graz, Graz, Austria.
Andreas
A
Gamillscheg
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D014694:Ventricular Outflow Obstruction / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*
RVOT systolic excursion; RVOT velocity time integral; atrial septal defect; children; right ventricular outflow tract (RVOT) diameter