Optimal noninvasive assessment of initial left ventricular dysfunction in children with ectopic atrial tachycardia.

UNLABELLED: Tissue Doppler imaging (TDI) can identify cardiac dysfunction in adults. This study is aimed to improve early identification of initial left ventricular (LV) dysfunction secondary to ectopic atrial tachycardia (EAT) in children by TDI. A total of 70 children with EAT were included in the present study. Cardiac function was evaluated by conventional echocardiography, TDI, and plasma N-terminal pro-brain natriuretic peptide (NT-proBNP). Doppler signals obtained from the mitral inflow and TDI of the mitral annulus were the average values of three consecutive heartbeats. Left ventricular ejection fraction (LVEF), peak early diastolic transmitral velocity (E), peak systolic mitral annulus velocity (S'), early diastolic mitral annular velocity (E'), the ratio E/E', and TDI-derived myocardial performance index (TDI-MPI) were compared between two groups of children with normal or elevated plasma NT-proBNP concentrations. Of the children, 18.6% demonstrated tachycardia-induced cardiomyopathy (TIC). Compared with LVEF, the TDI-MPI and E/E' showed better correlations with elevated plasma NT-proBNP. Addition of TDI-MPI and E/E' to LVEF provided increased information to detect elevated plasma NT-proBNP (91.67% sensitivity).
CONCLUSIONS: TIC occurred in 18.6% of children with EAT. Initial LV dysfunction assessed by the TDI-MPI and E/E' is associated with elevated plasma NT-proBNP, even the LVEF is normal.