Thanks for your question on Healthcare Magic.
I can understand your concern.
Yes, possibility of muscular twitching is more likely in your case but better to rule out heart diseases like
arrhythmia (rhythm disturbances in heart) because it is on left side of chest.
So first 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.
Sometimes calcium and
vitamin D3 deficiency can also cause similar muscular twitches. So get done calcium and vitamin D3 levels and if deficiency then you will need supplements.
You can also apply warm water pad on affected areas to prevent this twitching.
Don't worry, you will be alright.
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.