Brief Answer:
Get investigated as advised

Detailed Answer:
Hello,
I have gone through your question and understand your concern.
Shortness of breath can be due to pulmonary cause, cardiac cause or neural cause.
If respiratory examination and investigations are normal then respiratory cause is unlikely.
If 2D Echo testing is normal then cardiac cause is unlikely. Possibility of pulmonary hypertension should be ruled out on echo and ecg.
Myasthenia gravis is weakness of body muscle along with bulbar muscles causing fatiguablity, weakness, dysphagia and breathlessness.
Antibody testing for myasthenia, Repetitive nerve stimulation testing and neostigmine testing should be done for diagnosis.
Pyrridostigmine should be added along with steroids for benefits.
Hope you found the answer helpful.
Do get back to me for further information.
Regards
Dr N Kumar
Neurologist

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