If you have a strong family history of irregular heart rhythms then the little one too could be having a problem. Infants are known to suffer from arrhythmias. This can be serious or it may revert to normal rhythm on its own. For this further tests will be required. Please consult a cardiologist immediately if the emergency department detected something. Even otherwise, please show the child to a cardiologist. Take care!
The medical advice given should not be considered a substitute for medical care provided by a doctor who can examine you. The advice may not be completely correct for you as the doctor cannot examine you and does not know your complete medical history. Hence this reply to your post should only be considered as a guiding line and you must consult your doctor at the earliest for your medical problem.