A cevical sympathectomy is an operation that can be useful for some people with long QT syndrome. It reduces the amount of adrenaline that is produced and delivered to the heart by certain nerves (the left cervical ganglia). The operation involves blocking or removing these nerves on the left side of the neck. These nerves are not essential to normal function so you should not notice any major changes following the operation. The operation is a short one but you will need a general anaesthetic. This means that you will feel no pain during the operation and you will not remember anything about it.