Thanks for your question on Healthcare Magic.
I can understand your concern.
By your history and description, possibility of
arrhythmia (rhythm disturbances in heart) and COPD (chronic
obstructive pulmonary disease) is more.
Fluttering sensations in chest are mostly due to arrhythmia. And arrhythmia is common in smokers.
So
consult doctor and get done ecg, 2d echo and Holter monitoring (24 hours continuous recording of ecg).
If all these are normal then no need to worry for arrhythmia or other heart diseases.
You are also having breathlessness. So chances of COPD (emphysema or
bronchitis) is also high as you are active smoker.
Smokers are prone ti develop emphysema after the age of 40 years. So at 44 years of age, you are at risk of developing emphysema.
So
consult pulmonologist and get done clinical examination of respiratory system and PFT (pulmonary function test).
PFT will not only diagnose COPD but it will also tell you about severity of the disease and treatment is based on severity only.
You will improve with inhaled
bronchodilator and inhaled
corticosteroids (ICS).
In any case, quit smoking as soon as possible.
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.