Dizziness/presyncope can be divided into cardiovasular source and non
cardiovascular source.Cardiovascular causes include heartblocks, dysrthymias
,aortic stenosis,cardiomyopathy,so on....
Noncardiovasuclar causes include vasovagal reflex failure, systemic
orthostatic hypotension and neurogenic orthostatic hypotension(OH)..
If you don't have cardiac history, go back to noncardiogenic reasons. As
your MD said, 10% of pts can't find causes at all with these symptoms.
Hotbath will cause vasodilation inducing OH. Sitting or standing too long
will induce venous pooling and decrease blood volume back to heart causing
OH.Large meal will pool your blood to your GI tract and also reduce blood
volume to your heart. If you are young and also have a prodome of
diaphoresis,nausea,fatigue and pallor, I will go for vasovagal syncope for
your symptoms.
If you are vegetarian or on diet, please modify your diet.If you start some
new drugs or regimen right before this happening, please hold it to see the
difference. Try some salty food to increase your blood volume. Wear
compressing stocking or support socks to help you with venous blood return.
Check your Blood pressures while you are lying, sitting and standing. Avoid
hot bath, large meal and sudden position changes.
If you need find a different doctor, go to a neurologist or cardiologist.
Take care,
