Hi, Prolonged QT interval can result in irregular heart beats leading to unexplained fainting, seizures and life threatening conditions with irregular heart rates like Torsades de pointes(ventricular tachycardia), ventricular fibrillation or even sudden cardiac death. It can be congenital(from birth), or due to drug induced, metabolic abnormalities like hypocalcemia etc. The abnormal irregular heart rhythms can be precipitated by strenuous exercise or emotional excitement or in some case even sleep and loud noises may precipitate. I would suggest you to consult a Cardiologist at the earliest at OPD/ER who will take a detailed personal and family history to check for any similar episodes in any of the members of your family and do the appropriate investigations to find out the underlying cause for the condition and plan efficient management which can be medical or surgical. Hope I have answered your question. Please let me know if I can assist you further. Regards Dr Devi Venugopal Rita, MD General Medicine.