A rate of 250 bpm plus some of the symptoms you describe sounds like vtach.
My advise is that you get a full cardiac workup ASAP and listen to their treatment plan.
When the SVT starts you can try things like valsalva maneuvers or coughing to normalize the rate before it gets out of control. the longer you wait, the worse it will get.
I think it's very important that you get in to see a cardiologist.
p.s., I forgot to mention that VTACH is a ventricular arrhythmia. It's not SVT. It probably won't respond to the techniques I mentioned above.
svt is terrible..oh i really really hate having these episodes i was in the store yesterday and out of the blue i had a bad one..made it to my car(i dont know how)heart was poundings light headed.after about 15 minutes it ended.and i drove home.i have had ablation and it helped for a couple years but now its back and it's worse than ever.i cant take the meds.i cut out caffeine.but still i have the episodes.i'm not having ablation again.vagal works if you catch it soon very soon but not always.my cardio says its not life threating..i dont know..
hi
i would also seek to see a cardio or an ep for a definite diagnosis as fast as svt starts it should stop just as quickly words like almost unconcsious shows u need to have this checked and if needed some sort of meds prescribed .ablation is not as bad as it reads ,i had two for svt and have been feeling really good for mths with just the odd flip flop herre and there ..before i was getting svt attacks several times a day
take care