Relation of Right Atrial Strain to Mortality in Infants With Single Right Ventricles

Area of Science:

• Pediatric Cardiology
• Echocardiography
• Congenital Heart Disease

Background:

• Infants with single right ventricle (sRV) physiology often undergo palliative surgery.
• Post-operative surveillance is crucial for monitoring clinical outcomes in these high-risk patients.
• Echocardiography and B-type natriuretic peptide (BNP) are commonly used biomarkers.

Purpose of the Study:

• To investigate the association between echocardiographic parameters and B-type natriuretic peptide (BNP) levels with clinical outcomes in infants with sRV.
• To identify potential imaging markers for risk stratification in this population.

Main Methods:

• Prospective, single-center study of 26 infants with sRV following initial palliative surgery (Sept 2019 - Dec 2020).
• Echocardiograms and paired B-type natriuretic peptide (BNP) measurements were collected.
• sRV functional assessment included subjective grade, fractional area change, tricuspid annular plane systolic excursion, global longitudinal strain, and right atrial strain (RAS).

Main Results:

• Five patients (19%) experienced the primary outcome (death/heart transplant), showing significantly lower right atrial strain (RAS) compared to survivors (14.1% vs 21.3%, p=0.038).
• RAS demonstrated the highest area under the curve (0.83) for predicting outcomes, followed by global longitudinal strain (-14.4%, 0.77).
• Higher RAS was associated with shorter milrinone duration (p=0.02) and increased odds of digoxin use (p=0.047), while higher BNP was linked to lower odds of digoxin use (p=0.03).

Conclusions:

• Right atrial strain (RAS) emerged as a significant imaging marker in infants with sRV, potentially predicting clinical outcomes.
• RAS may be a valuable tool for risk stratification and guiding management in this vulnerable population.
• Further investigation in larger cohorts is warranted to validate these findings.