Are inverted T waves significant?

Hi there,
I have recently undergone various investigations for palpitations and tachycardia. All routine bloods and a chest xray have been normal, however I was found to have episodes of sinus tachycardia of 160 bpm (max) and inverted 'T' waves on a 24hr ecg. An ecg at my surgery also showed me to have an isolated episode of a QTc of 490. I was then referred for an echocardiogram which was normal. I have now been placed on a beta-blocker (Bisoprosol 2.5 mg) which is helping with my racing heart rate but I still get palpitations on mild excertion and even after just one glass of wine!  I am regularly very tired and feel faint when I stand up.

I am a 29 year old non-smoking female, I am not overweight, nor do I drink much alcohol. I do have a family history of myocardial degeneration and cornonary sclerosis.

I would be very grateful for any advice and thank you.

[Cleveland Clinic]

I would recommend being seen by an electrophysiologist to sort this out, because there are some conditions that could cause abnormal T waves and a prolonged QT interval.  In the setting of palpitations one would worry about abnormal rhythms coming from the lower chambers of the heart and this would be of significant concern necessitating further workup.  

[Sheshez]

Thank you so much for your prompt reply, I will take this information to my GP and see if he can arrange for me to be referred to a cardiologist.

Many thanks again