Greetings from healthcaremagic.com
i am Dr Sourav Chakraborty and i will be helping you with your query .
Your symptoms inclusive of your multiple holter reports are suggestive of either panic attacks or general axiety disorder . Both of them can present with fast heart beat, breathlesness , loss of sleep and some times chest pain
, well rarely .
You need to relax and engage yourself in some stress
relieving exercises like yoga
Though there are medications but i would recommend as the first line of management as patients do get addicted to such and then dose are subsequently increased which can lead to added side effects.
Please talk to your primary physician for more information.
Hope i have been able to help you.