Reference Values for Pediatric Atrial Volumes Assessed by Steady‐State Free‐Precession Magnetic Resonance Imaging Using Monoplane and Biplane Area‐Length Methods.

Background: Measurement of atrial volumes by MRI is becoming increasingly important in pediatric cardiac disorders. However, MRI normal values for atrial volumes in children are lacking. Purpose: To establish pediatric reference values for atrial volumes. Study Type: Retrospective. Subjects: A total of 155 healthy children from two large institutions (103 male, age 13.9 ± 2.8 years, range 4–18 years). Field Strength/Sequence: A 1.5 T; balanced steady‐state free precession (bSSFP) sequence. Assessment: The monoplane and biplane area‐length methods were used to measure minimal and maximal left and right atrial volumes (LAmin, LAmax, RAmin, and RAmax) from four‐chamber (4ch) and two‐chamber (2ch) MR cine images. Centile charts and tables for atrial volumes were created. Statistical Tests: Descriptive statistics, lambda‐mu‐sigma (LMS)‐method of Cole and Green, univariable and multivariable linear regression models. A P value < 0.05 was considered to be statistically significant. Results: In the multivariable linear model, body surface area was significantly associated with all atrial volumes and sex was significantly associated with RA volumes, LA volumes measured in the 2ch‐view as well as biplane LAmax. Average atrial volumes measured: monoplane 4ch: LAmin 13.1 ± 4.8 mL/m2, LAmax 33.4 ± 8.8 mL/m2, RAmin 18.5 ± 6.8 mL/m2, RAmax 33.2 ± 9.6 mL/m2; monoplane 2ch: LAmin 12.7 ± 4.9 mL/m2, LAmax 30.5 ± 9.5 mL/m2; biplane: LAmin 12.3 ± 4.5 mL/m2, LAmax 30.9 ± 8.7 mL/m2. Data Conclusion: Pediatric MRI reference values for atrial volumes have been provided. Technical Efficacy: 2 Evidence Level: 4 [ABSTRACT FROM AUTHOR]