Long QT syndrome causes?

If they felt that the methadone had caused his cardiac arrhythmia, they would not put in the defibrillator, they would of waited for the drugs to clear his system and observed him. He must of demonstrated while he was in hospital that he had a prolonged QT interval and had a cardiac arrhymia ociated with it. There are several reasons why the QT was prolonged and perhaps your brothers rreason(s) where discovered while he was in hospital. I don't think the drugs had anything to do with his cardiac arrest, unless he had taken them and perhaps stopped breathing. He's only 20, and he is allowed to make mistakes as we all do from time to time. You should be evaluated in case this problem is hereditary also.