0164: Validation of two-dimensional speckle tracking strain for assessment of early right ventricular dysfunction: in vivo and ex vivo study

Background Right ventricular (RV) dysfunction is a major determinant of long-term survival in congenital heart diseases. Early echo detection of RV failure is mandatory, but recent indices need to be validated. Aims Objectives were to: (1) validate standard and strain echo indices for evaluation of RV systolic function, compared to hemodynamic parameters; (2) assess the accuracy of these indices for early detection of RV failure. Methods Combined RV overload as observed in repaired tetralogy of Fallot was surgically reproduced in 2-month-old piglets (n=6). Age-matched piglets were used as controls (n=4). RV function was evaluated at baseline and 4 months of follow-up by standard and strain echo indices, compared to conductance catheter. Sarcomere shortening and calcium transients were recorded in RV isolated myocytes (IonOptix). Contractile reserve was assessed by in-vivo (dobutamine 5µg/kg) and ex-vivo (isoprenaline 100nM) β adrenergic stimulation. The integrity of T-tubules was controlled after Di-4-Anepps labeling. Results 4 months after surgery, hemodynamic RV ejection fraction (FEVD) was significantly decreased (29.7% [26.2-34] vs 42.9% [40.7-48.6], p Conclusion In this model, both standard and strain echo indices allowed the detection of early impairments of RV function and cardiac reserve, which are associated with cardiac excitation-contraction coupling alterations.