Contraction patterns of the systemic right ventricle: a three-dimensional echocardiography study

Area of Science:

• Cardiology
• Medical Imaging
• Congenital Heart Disease

Background:

• Transposition of great arteries (TGA) and congenitally corrected TGA (ccTGA) are complex congenital heart defects.
• The systemic right ventricle (SRV) in these conditions undergoes unique functional adaptations.
• Understanding SRV contraction patterns is crucial for managing patients post-surgical correction.

Purpose of the Study:

• To investigate and compare the contraction patterns of the SRV in patients with TGA post-atrial switch and ccTGA.
• To analyze the contributions of longitudinal, radial, and anteroposterior components to SRV ejection fraction (EF).
• To correlate SRV function with clinical markers like B-type natriuretic peptide (BNP).

Main Methods:

• Three-dimensional echocardiography was used to assess RV volumes and EF in 38 SRV patients (24 TGA, 14 ccTGA) and 38 controls.
• SRV contraction was decomposed into longitudinal, radial, and anteroposterior components (LEF, REF, AEF) and their contributions (LEFi, REFi, AEFi).
• Correlation analysis was performed between SRV EF, longitudinal strain, and BNP levels.

Main Results:

• SRV in patients was larger with reduced systolic function compared to healthy controls.
• SRV EF and longitudinal strain strongly correlated with BNP levels.
• In TGA, the anteroposterior component (AEF, AEFi) was dominant, unlike in ccTGA where components were similar. AEFi was higher in TGA vs. ccTGA.

Conclusions:

• SRV contraction patterns are distinct in TGA and ccTGA, with TGA exhibiting a dominant anteroposterior component for compensation.
• In ccTGA, all contraction components contribute equally to SRV EF.
• SRV EF and longitudinal strain are significant indicators of cardiac function and correlate with BNP, warranting routine echocardiographic assessment.