can sinus tachycardia lead to electrical or structure damage of the heart?

[CristianC908]

When i was 18 years old i started experiencing a very disturbing tachycardia. After attempting to walk blocks i would get heart rates in the 100s and upper 200s or lower 200s. At that time my heart would beat very fast but it felt like a strong solid pump so it actually felt healthy to me. Prior to the tachycardia i was severely inactive for about a year or two. Im not sure if the tachycardia began from a lack of a good all around diet, or what was the cause. However this tachycardia continued on for about another year because i was literally unable to do alot of things so i just pretty much got used to my heart beating so fast in a way. I was immediately investigated by a cardiologist (assistant) where i got sent for a blood test, urine, stress test, echo, and chest x ray. Everything came back normal thankfully and again i saw the assistant. I highly regret not actually seeing a cardiologist or asking to see one when i got sent for tests because i believe it would have changed the outcome of my situation in a way. Long story short the tachycardia has never gone away and im not sure if its from again the same cause (lack of good nutrition). I will finally be able to fulfill my dietary needs very soon because i am starting a job regardless of the tachycardia but i am not sure if my heart can become damaged from beating so fast for a year or more. My heart beats alot different now and im getting chest pains constantly and i went from having sinus tachycardia to experiencing svt, pvc, pac, efc. I'm not sure if i have in someway acquired sick sinus syndrome just from my heart beating so fast for so long although there has been alot of rest because i really dont do much as of right now. I am aware that tachycardia episodes of 200 bpm would not damage the heart unless it happened very frequently but in the past year i have had tachycardias that have lasted a few hours or more at that and i hope theres no structural damage with my heart. So mainly my question is, my heart went from feeling healthy and in sync at the time i underwent tests, to a almost constant bounding pulse i feel everyday since 6 or so months after testing was done. I will have insurance in a month or so but i have had ekg's in the past 3 months and im not sure if a ekg can pick up the actual size of the heart. Another thing is, if i get another echo, should it be stress echo or normal echo and should i pick up the results of the echo last year if i can ? Thanks any advice welcome.