Table 1 Demographic features and baseline clinical features of the study group

Features	Description	No.
Age at presentation	3 Weeks–8 months (median 5.3 months)	16
Sex	Male	10
Race	Afro-Caribbean	10
	Indian subcontinent	6
Presenting season	February to May	10
Feeding	Exclusively breast fed	12
	Breast fed + solids	4
Cardiac presentation	Heart failure	10
	Cardiac arrest	6
Intensive care support	Ventilation	8
	Inotropic support	12
	Extracorporeal membrane oxygenation	2