<prompt> Commonest cause of hea failure in infancy is:MyocarditisRheumatic feverCardiomyopathyCongenital hea disease  <response>: -- The most common cause of Congestive hea failure CHF in infants-- Congenital hea disease. OTHER IMPOANT ONE LINERS: -- MC congenital hea disease in children -- VSD -- MC congenital acyanotic hea disease in children -- VSD -- MC congenital hea diseases affected by infective endocarditis in children -- VSD -- Congenital hea disease which is least commonly affected by Infective endocarditis -- ASD -- MC congenital hea disease causing moality in 1st wk of life -- Hypoplastic Left Hea Syndrome. 