Right Ventricular Outflow Tract Velocity Time Integral Determination in 570 Healthy Children and in 52 Pediatric Atrial Septal Defect Patients

Abstract

Determination of the right ventricular outflow tract velocity time integral (RVOT VTI) is an important part of the noninvasive investigation of pulmonary blood flow in adults; however, age-related pediatric reference data are lacking. We examined growth-related changes of RVOT VTI values in children and the predictive value of RVOT VTI values in identifying enhanced pulmonary blood flow in children with secundum type atrial septal defect (ASD). A prospective study was conducted in a group of 570 healthy children and 52 children with a moderate-sized to large ASD. We determined the effects of age, body length (BL), body weight (BW), and body surface area (BSA) on RVOT VTI values. The predictive value of normal values stratified for age, BW, BL, and BSA was tested in our 52 ASD children. RVOT VTI values ranged from mean 9.7 ± 1.2 cm in neonates to 23.3 ± 2.7 cm in children with 18 years of age and showed a positive correlation with age, BL, BSA, and BW. In our population, RVOT VTI z-scores showed a high specificity for detecting ASD patients (>97 %) with sensitivity up to 71 %. We provide normal ranges and calculated z-scores of pediatric RVOT VTI values. Normal RVOT VTI z-scores might be additional predictors in identifying increased pulmonary blood flow in patients with ASD.

Transthoracic Echocardiography in the Evaluation of Pediatric Pulmonary Hypertension and Ventricular Dysfunction

“…Normative pediatric RVOT VTI values were recently published. 45 These normative RVOT VTI values will help to overcome the problem of the currently limited use of the TRV/RVOT VTI ratio in children.…”

The right ventricular outflow tract in pediatric pulmonary hypertension—Data from the European Pediatric Pulmonary Vascular Disease Network

“…Importantly, patients must be in sinus rhythm at the time of the echocardiogram. After manually tracing the PW Doppler spectrum, RVOT VTI values were measured by applying the calculation package of the ultrasound unit and are equal to the area enclosed by the baseline and Doppler spectrum …”

“…Data are presented as mean and standard deviation or median and range for continuous data, and absolute and relative frequency for categorical data, respectively. Age‐adjusted RVOT VTI z ‐scores were calculated according to a previous study …”

“…Inter‐observer and intra‐observer reliability of echocardiographic measurements ranges from ICCintra: .97‐.99 for intra‐observer reliability and from ICCintra: .88‐.99 for inter‐observer reliability . Data are presented as mean ± SD.…”

“…Data are presented as mean ± SD. Age‐specific z ‐scores were calculated according to published algorithms (RVOT diameter, RVOT SE, and RVOT VTI). One sample t test was used to analyze whether age‐specific z ‐scores differ from zero and therefore are increased or decreased compared to normal age‐specific values.…”