I am 52 years old, overweight, no HTN, no high cholesterol, hypothyroid w / MNG. MY ECG says sinus rhythm, minimal high -lateral repolarization disturbance, probalbly aspecific change. flat or low negative T in aVL. normal variant of ECG. but...I have had a few epsiodes of tachyicardia and lightheadedness, SOB sometimes. I go for my echo this week and see a cardiologist soon, but I want to know possibilities. I can papate an irregulate beat also.