Hello and thank you for using HCM. I carefully read your question and i totally understand your concern. I will try to explain you something and give you my opinion. You should not worry for your electrocardiogram report. First of all, you should not read what the paper says, because it is just a computer explanation. The electrocardiogram should allways be interpret by the doctor, not the machine. If it is the doctor that gave this interpretation, again you should not worry. Sinus arrhythmia might be normal at your age. Re polarization disturbance is just an electrical term that means nothing at your age. What we should worry are your symtoms during this years. As you explain we are dealing with a rhythm issue. Someone might experience fast heart beats for very different reasons and pathologies. It might be simple sinus tachycardia to other arhythmias like supra-ventricular tachycardia, atrial fibrillation ect. This are caused from different problems from simple emotional stress to other pathologies like anemia, hyperthiroidism or electrical conduction system anomalies. The aberrant subclavian artery does not cause this symptoms but might rise a suspicion of any anatomic variation on your electrical conduction system of your heart. So my opinion is that now its time to meet the cardiologist and do all the thinks that you have planed to do. The most important the holter monitoring, preferably for 48 h. This will help to see what are this fast heart beats. In mean time avoid caffeine products because they rise your heart frequency. Hope I was helpful. Best regards