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

Aims To investigate contraction patterns of the systemic right ventricle (SRV) in patients with transposition of great arteries (TGA) post-atrial switch operation and with congenitally corrected transposition of great arteries (ccTGA). Methods and results Right ventricular (RV) volumes and ejection fraction (EF) were measured by three-dimensional echocardiography in 38 patients with the SRV (24 TGA and 14 ccTGA; mean age 45 +/- 12 years, 63% male), and in 38 healthy volunteers. The RV contraction was decomposed along the longitudinal, radial, and anteroposterior directions providing longitudinal, radial, and anteroposterior EF (LEF, REF, and AEF, respectively) and their contributions to total right ventricular ejection fraction (LEFi, REFi, and AEFi, respectvely). SRV was significantly larger with lower systolic function compared with healthy controls. SRV EF and four-chamber longitudinal strain strongly correlated with B-type natriuretic peptide (BNP) level (Rho -0.73, P < 0.0001 and 0.70, P < 0.0001, respectively). In patients with TGA, anteroposterior component was significantly higher than longitudinal and radial components (AEF 17 +/- 4.5% vs. REF 13 +/- 4.9% vs. LEF 10 +/- 3.3%, P < 0.0001; AEFi 0.48 +/- 0.09 vs. REFi 0.38 +/- 0.1 vs. LEFi 0.29 +/- 0.08, P < 0.0001). In patients with ccTGA, there was no significant difference between three SRV components. AEFi was significantly higher in TGA subgroup compared with ccTGA (0.48 +/- 0.09 vs. 0.36 +/- 0.08, P = 0.0002). Conclusion Contraction patterns of the SRV are different in TGA and ccTGA. Anteroposterior component is dominant in TGA providing compensation for impaired longitudinal and radial components, while in ccTGA all components contribute equally to the total EF. SRV EF and longitudinal strain demonstrate strong correlation with BNP level and should be a part of routine echocardiographic assessment of the SRV.

Automated summary

The contraction patterns of the systemic right ventricle differ between patients with transposition of great arteries post-atrial switch operation and those with congenitally corrected transposition of great arteries. In patients with TGA, the anteroposterior component is dominant in compensating for impaired longitudinal and radial components, while in patients with ccTGA, all components contribute equally to the total ejection fraction. Strong correlations are observed between SRV EF and longitudinal strain with B-type natriuretic peptide levels, indicating the importance of routine echocardiographic assessment of the SRV.