Hi, I am new to all this. Over the last three years I have had 2 seizures, the first time I was rushed to hospital and had all the usual tests, then couldn't drive for 6 mths, the latest was this June. Had all the usual tests and the original diagnosis was epilepsy. The MRI and EEG tests were ok. Now after having a 24 hr Holter heart monitor the results were SVT, 15 seconds. Which might be the cause for the blackouts, but they were not ordinary fainting spells. I have been on anti depressants for almost 5 years and are decreasing them, lost 2 st In weight intentionally, now I have this problem. My GP prescribed beta blockers to take when I feel anxious etc. which is usual for me. I have felt something was "not quite right' for years, but regular ECGs didn't show any irregularities. Now, I am not panicking but am a bit concerned. Can anyone explain In simple english what all this might mean please . SVT is all new to me, is it serious?