Reason Of Tachycardia Tachycardia, But All Tests Are Normal?

Tachycardia, but all tests are normal? - reason of tachycardia

'm 24 years, Non smoking. My heart was about 115 beats per minute and up to 130-40, as with any type of activity. I had blood tests, EKG and echo. Everything was normal. The only symptom if you are short of breath and blows most of the time complain about the feeling. I must admit I was very vague, almost nothing, and depressed in recent months and wondered if the reason for my tachycardia, that I'm in shape? Is this possible?

My brother had similar problems and the cardiologist, who is basically saying that he is overweight and out of shape.