Novel Z Scores to Correct Biases Due to Ventricular Volume Indexing to Body Surface Area in Adolescents and Young Adults

Mikhail-Paul Cardinal, Samuel Blais, Anne Dumas, Vincent Hamilton, Eric Larose, Stéphanie LeBlanc, Julie Déry, Heynric Grotenhuis, Tim Leiner, Wadi Mawad, Cassandre Têtu, Steven C Greenway, Nicole Dahl, David Patton, Arif Hussain, Christian Drolet, Gérald Gahide, Paul Farand, Daryl Schantz, Frederic Dallaire

Research output: Contribution to journalArticleAcademicpeer-review


Background: Reference values for cardiac magnetic resonance imaging (cMRI) in children and young adults are scarce. This leads to risk stratification of patients with congenital heart diseases being based on volumes indexed to body surface area (BSA). We aimed to produce cMRI Z score equations for ventricular volumes in children and young adults and to test whether indexing to BSA resulted in an incorrect assessment of ventricular dilation according to sex, body composition, and growth. Methods: We retrospectively included 372 subjects aged < 26 years with either normal hearts or conditions with no impact on ventricular volumes (reference group), and 205 subjects with repaired tetralogy of Fallot (TOF) aged < 26 years. We generated Z score equations by means of multivariable regression modelling. Right ventricular dilation was assessed with the use of Z scores and compared with indexing to BSA in TOF subjects. Results: Ventricular volume Z scores were independent from age, sex, and anthropometric measurements, although volumes indexed to BSA showed significant residual association with sex and body size. In TOF subjects, indexing overestimated dilation in growing children and underestimated dilation in female compared with male subjects, and in overweight compared with lean subjects. Conclusions: Indexed ventricular volumes measured with cMRI did not completely adjust for body size and resulted in a differential error in the assessment of ventricular dilation according to sex and body size. Our proposed Z score equations solved this problem. Future studies should evaluate if ventricular volumes expressed as Z scores have a better prognostic value than volumes indexed to BSA.

Original languageEnglish
Pages (from-to)417-424
Number of pages8
JournalThe Canadian Journal of Cardiology
Issue number3
Early online date22 Jun 2020
Publication statusPublished - Mar 2021


Dive into the research topics of 'Novel Z Scores to Correct Biases Due to Ventricular Volume Indexing to Body Surface Area in Adolescents and Young Adults'. Together they form a unique fingerprint.

Cite this