Brief Answer:

Need some further details regarding.

Detailed Answer:

Hello,

Please note, at this age group the first and foremost priority is to rule out the major causes for this.

The Cardiac check-up should be done thoroughly. So it's the right decision to go ahead with the further check-ups to rule out any cardiological risks.

Apart from the ECG, a 2D-echocardiography is a must which will show the heart's chambers as well functions, if normal, then the next step will be a TMT or treadmill test to evaluate the cardiac rhythm and coronary blood -flow, if that comes normal then it's pretty much confirmed that there's no concern from the cardiological point of view.

4years is a long time, please let me know what all blood tests were done during that time and how long back the ECG was done.

Any history of any other medical/surgical ailments?
Are you taking any medications for any other reasons?
Any history of trauma/injury to the upper limb/spine?
Any history of smoking/alcohol?
Any family history of cardiac ailments?

However, from your present complaints, since there's also feeling faint and pins & needle feeling in Chest arms and left thigh.

I'd suggest to go ahead and take another opinion of a Neurologist as TOS (I believe you meant Thoracic Outlet Syndrome) needs a complete neurological check-up as well as few specific investigations (X-rays and MRI of the Upper limb as well as the Cervical and Thoracic spine, EMG studies etc).

Additionally, the Vitamin-B12; VitD3, serum Calcium levels, ESR and CRP (mainly done to check the inflammatory markers) should also be checked (if already done then fine)...

Costochondritis may cause some of those symptoms but definitely no fainting and involvement of left thing...

Hope I have answered your query.

Take care

Regards,
Dr Arnab Banerjee, Critical Care Specialist

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