Echocardiographic Strain and Nt–probnp in the Systemic Right Ventricle: Complementary Indicators of Hemodynamic Severity

Background The systemic right ventricle (sRV), present in patients with d–TGA after atrial switch and in congenitally corrected TGA (ccTGA), is chronically pressure–loaded, leading to ventricular remodeling and progressive dysfunction. In this setting, markers of myocardial mechanics and wall stress integrating imaging and biomarkers are useful. Aim To evaluate the association between NT–proBNP and sRV longitudinal strain (four–chamber strain, RV4CSL, and free–wall strain, RVFWSL) and, secondarily, to describe its relationship with conventional echocardiographic indices (FAC, TAPSE, TDI S′) in a GUCH cohort with sRV in biventricular circulation (Mustard/Senning and ccTGA). Methods Retrospective study of 20 patients followed at our Center (ARNAS Civico–Di Cristina, Pediatric Cardiology Unit). All underwent comprehensive clinical assessment with functional evaluation, laboratory testing, ECG/Holter and echocardiography; speckle–tracking strain was available in 13/20 patients (Figure 1-2). Associations were explored using linear models and Pearson correlation; NT–proBNP was also log–transformed (log10) and results were checked with Spearman as a sensitivity analysis for outliers. Results In patients with complete echocardiographic strain and NT–proBNP data (n=13), RVFWSL was inversely associated with NT–proBNP (Pearson r=−0.555; p=0.049; Spearman ρ=−0.527; p=0.064) (Figure 3A), suggesting that reduced longitudinal deformation (less negative strain values) is accompanied by greater neurohormonal activation. RV4CSL also showed a consistent inverse association with NT–proBNP (Pearson r=−0.509; p=0.076; Spearman ρ=−0.591; p=0.033) (Figure 3B), with less negative RV4CSL values associated with higher NT–proBNP. As a complementary analysis, higher FAC was associated with higher absolute RV4CSL (r=0.624; p=0.023), whereas TAPSE and TDI S′ showed weaker but concordant associations. Conclusions In our biventricular–circulation sRV cohort, higher NT–proBNP is associated with worse longitudinal mechanics, particularly at the free wall. Interpreted together, strain and NT–proBNP may help grade hemodynamic severity and guide follow–up; these exploratory findings require confirmation, using additional diagnostic modalities.