Welcome to HealthcareMagic forum.
As you have been diagnosed with enlarged left atrium, the size of the enlargement is very important in accessing the severity of it.
I advice you to try and quit smoking
as it is the main cause for your symptoms, the heart is under stress
levels fall , which happen with smoking, also we all know smoking leads to tremors , palpitations ,etc, you could start with nicotine
gums and slowly stop this habit.
If you feel this heaviness and palpitations, try deep breathing exercises and meditate as well, avoid getting anxious or losing temper , as again this puts the heart into stress.
also avoid coffee, tea, etc, minimize them
This will surely help you, continue your medicines .