Why Do I Feel Rapid Heart Rate While Sitting Or Standing?
Welcome to XXXXXXX forum.
Feeling fast heart rate is called as "Palpitations".
Palpitations may be due to heart problem or due to hormonal problem.
Heart problem may be in form of conduction defects and missed beats.
Hormonal problems may be hyperthyroidism, pheochromocytoma and cushing's syndrome.
You should consult with XXXXXXX medicine speacialist and should go for thorough check up.
You should go for electrocardiography on priliminary basis to rule out any heart related disease.
You should also go for thyroid profile, serum epinephrine & norepinephrine level and vanniyl mandelic acis level, serum ACTH level.
You can also go for electrophysiological studies of heart.
If all these investigations are normal then there may be also be possibility of panic attacks also, as you are already suffering from PTSD and GAD.
You should also consult with psychiatrist.
Treatment depends on the diagnosed disease.
Hope that helps.
Let me know if I can address any more concerns.
Take care,
Dr. Mayank Bhargava
Any type of heart conduction disturbances may be associated with impaired blood supply to brain and may cause dizziness along with pounding sensation in head and eyes.
This may be a part of panic attacks also.
Take care,
Dr. Mayank Bhargava