Table 2 Definitions of heart failure

a) Clinical: probable congestive cardiac failure (CCF) scored on a scale ranging from 0 to 5 based on the following signs listed in the WHO guidelines [1]: (1) tachycardia (heart rate >160/minute in a child <12 months of age or >120/minute in a child aged 12 months to 5 years); (2) tachypnoea; (3) gallop heart rhythm; (4) tender hepatomegaly and (5) raised jugular venous pressure seen as distended neck veins. We used a score ≥3 as the cut-off for probable CCF.

b) Echocardiographic: myocardial dysfunction (MD) definition was based on the left-ventricular Tei index >0.4 [45–47].

c) Biochemical: brain natriuretic protein (BNP) >300 pg/ml [11, 12].