Thanks or the additional information,
Now there can be a few causes for this symptom of yours and the commonest one is that of Orthostatic Hypotension which would cause the symptoms as well as the rise in heart rate specially on standing up. This is espeically true since youre taking terazosin which is known to cause this problem and also reflex tachycardia. This means that when you stand up the pooling of blood in the extremities is so muc so that the blood doesnt return adequately to your heart and as a result decreased blood flows to your brain due to decreased BP causing the symptoms. The drop in BP would also cause the heart rate to increase as well thus jumping from say 80 to 130 or so. This can be remedied by using stockings and slowly standing up. Plus using a different drug can also be helpful or reducing the dose can help as well.
Now there is another condition which can cause the bloating, tachycardia and even erctile problems which is known as autonomic neuropathy. This can cause resting tachycardia meaning that the heart rate would jump up even if you were doing nothing. This is due to the fact that the autonomic nervous system which is controlling the heart and the stomach is damaged due to some cause which can be diabetes or even other causes. This can be diagnosed by several tests like tilt table testing, QSART testing, Gastric motility tests. there are several treatment options available for this, which you can read about in detail at the link im giving below,
Now another cause can be an arrhythmia which is an abnormal rhythm of the heart or irregular rhythm, this can cause the symptoms as well and the fluctuating heart rate. As youre already wearing a holter monitor then its fine as this will pick up the changes in rhythm and heart rate if any are occuring. Any change in the rhythm would then be analyzed and according to the rhythm treatment can be started with beta blockers or calcium channel blockers etc.
I hope this answers your question
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