Thanks for your question on Healthcare Magic.
I can understand your concern.
Fluttering sensations in chest are commonly seen
arrhythmia (rhythm disturbances in heart).
For the diagnosis of arrhythmia, Holter monitoring (24 hours continuous recording of ecg) is required.
I think, you have not undergone this test.
So
consult cardiologist and get done Holter monitoring to rule out arrhythmia.
If this is normal then no need to worry for arrhythmia or other heart diseases.
Sometimes, uncontrolled stress and
anxiety can also cause similar kind of Fluttering sensations.
So
consult psychiatrist and get done
counselling sessions.
Try to identify stressor in your life and start working on it's solution. You may need anxiolytic drugs too.
Don't worry, you will be alright. Avoid stress and tension, be relax and calm.
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.