Primary cardiac tumours (PCT) are rare in the paediatric population. They can present in a variety of ways – from being asymptomatic, obstructive with heart failure, strokes, arrhythmias or sudden death. We present a 2-month-old child who was admitted because of heart failure from varying types of arrhythmias and was found on echocardiography to have a large left ventricular tumour. A high clinical suspicion in any infant or child who presents with an unexplained heart murmur, arrhythmias or congestive heart failure should prompt relevant investigations ruling out this entity.