Lately i`ve had a tachycardic heart and sometime dizziness and chest pain what could cause it? I`m an 18 year old girl who keeps herself fit, never had to stay in a hospital, and never had any kind of procedures.

CP. This is, of course, too little information to give you a firm answer. Posssibilites range from anemia (low blood count) to anxiety or high thyroid function. If these are new symptoms, please see your family doctor for a checkup!
Fast . Fast heart beats and tachy cardia is a common finding in young ladies. Approximately 1 in sixteen ladies will get tachy cardia due to avnrt. Usually the first step is to capture the arrythmia on a moniter. I usually start with a 24 hour moniter or an event moniter. The treatment can range from beta blockers to vagal maneuvers ot ablation. You do need to get an ECG done to see if you have wpw.