Abstract: Objective To explore the prevalence and predictors of left ventricular reverse remodeling after drug therapy in children with new-onset dilated cardiomyopathy. Methods The clinical data of new-onset dilated cardiomyopathy and endocardial fibroelastosis were retrospectively analyzed in 55 children who were hospitalized from February 2012 to November 2018 and were followed up to January 2020 or death. The standard drug treatment was given to the children after hospitalization and discharge. Left ventricular inverse remodeling was defined as an increase in left ventricular ejection fraction (LVEF) by ≥ 10% from baseline and LVEF≥ 55 % during follow-up, and at the same time a decrease by ≥ 10% in left ventricular enddiastolic dimension z score (LVEDD-Z) after body surface area standardization from baseline and LVEDD-Z≤ 2 . The incidence of left ventricular inverse remodeling was investigated according to echocardiography results. The clinical and echocardiographic findings were collected at children's first admission. The baseline predictors of left ventricular reverse remodeling were analyzed by multivariate logistic regression. Results There were 55 children ( 16 males and 39 females) with a median age of 7 months (range: 23 days to 13 years and 2 months). After a median follow-up of 33 months (range 1 ~ 85 months), 25 children were found to have left ventricular reverse remodeling by echocardiography. The LVEF increased from ( 37 . 1 ±7 . 4 )% at admission to ( 65 . 7 ± 5 . 4 )% at follow-up, LVEDD-Z decreased from ( 9 . 5 ± 3 . 0 ) at admission to ( 1 . 3 ± 0 . 6 ) at follow-up, and the differences were statistically significant (P< 0 . 001 ). Univariate logistic regression analysis showed that pulmonary hypertension, moderate to severe tricuspid regurgitation and serum albumin level were associated with left ventricular reverse remodeling in new-onset dilated cardiomyopathy in children. Multivariate logistic regression analysis showed that neither moderate nor severe tricuspid regurgitation was an independent predictor of left ventricular reverse remodeling in recent-onset dilated cardiomyopathy in children (OR= 9 . 75 , 95 %CI: 1 . 03 ~ 87 . 62 , P< 0 . 05 ). Conclusions Nearly half of the children with recent-onset dilated cardiomyopathy can develop left ventricular remodeling after medical treatment, and children with moderate to severe tricuspid regurgitation are more likely to have left ventricular remodeling.

Key words: dilated cardiomyopathy; endocardial fibroelastosis; left ventricular reverse remodeling; drug therapy; child