I AM 43 YEAR OLD FEMALE, THE SYMPTOS A HAVE BEEN EXPERIENCING ARE PALPITATIONES Y SOME TIMES CHEST PAIN, FOR 2 YEARS . MAY HEART SPEED UP 140, 150 BEATS FOR MINUTE, THERE IS NO EVIDENCE FOR SVT, ONLY SINUS TACHICARDYA. MY DOCTTOR DID A LOT OF TEST, BUT NO DIAGNOSTIC. I NEED HELP PLEASE.