What Causes Blurred Vision And Tremors In The Legs?

For several years I have had varying blood pressure. Sometimes too high sometimes too low. A tilt test determined situational hypotension. However, it does not always occur just when getting up. I can be walking a block down the street and experience scope. I have passed out several times. Other times my vision becomes blurred and friends say my legs shake. If I can sit down and wait it goes away. A heart specialist has done tests including stress test, EKG and heart ultrasound and found nothing. She left me about five months ago with You will either get better or it will get worse and we will know what it is. The last month has seemed to have gotten worse. My question is should I continue with a heart specialist, neurologist, ear doctor or what??