The best answer is "It depends"
I never passed out but sometimes when I was in a-fib my rate would vary so widely that there wold be priods where my rate was below 30bmp - 2 seconds or longer between beats. I never had those periodd (ove brady) last very long but if the bout of brady lasted more than a minute or so I did start to gray out.
Are you currently on any rhythm medication? How frequent do these bouts of a-fib seem to be? I was having problems for over a year before it was caught at an annual physical. BTW, recurring bouts of a-fib is called PAT (Paroxysmzl Atrial Tachycardia) or PAF (Paroxysmzl Atrial Fibrillation) and it can be completely idiopathic - i.e. no observable cause.
If you are not on any meds but the a-fib episodes are frequent you need to talk to your cardiologist about controlling your atrial rhythm with medication. My cardiologist told me that PAT is not usually life threatening since by definition the rhythm wold return to normal sinus on its own.
Unfortunately, it is not uncommon for PAT/F to degenerate into chronic a-fib. Once that happens you need to be on "blood thinners" (meds to icrease your clotting time) because chronic a-fib can lead to the formation of clots. If those clots get out of the heart bad things happen.
If you are not already under a Cardiologist's care I urge your to find one and start working with them. A-fib is not of itself lethal but it can have lethal effects.
FYI, I was diagnosed with PAT in 1998. I went through several different rhythm meds. Untimately in the fall of '07 I was found to be in continuous a-fib. The result was not only an irregular rhythm but an irregularly irregular rhythm. My rate would go from 130 bpm from moment to moment with no rhyme or reason. They tried cardioversion but it didn't take. We tried RF ablation but my atria are too large. In April of '08 I had my AV node ablated and a pulse generator (pacemaker) installed. I nonow have a steady rate of 60 bpm. It even sounds normal if you listen to it.
Good luck keep us posted.
Any level of AFib suggest to me some anticoagulant therapy is needed. If AFib is rare a simple aspirin a day may be sufficient, if your stomach can tolerate the aspirin.
I am in full-time AFib, so I take warfarin to reduce the chance of clot formation, the main concern for those of us with AFib but few other symptoms. I also take Metoprolol to control/reduce my HR. With Metoprolol my rest HR ranges from the 70s to upper 80s, an acceptable range. I have never blacked out, and the few times I have been dizzy/ligh-headed were when I was on a high dose of Metoprolol, I was as high as 200 mg a day. I've just today dropped from 100 mg to 50 mg, and will see how my HR reacts.
Some of us AFib'ers are "lucky" symptom-wise, unlucky treatment wise, e.g., my EP and my cardiologist both advise against trying an ablation, which has some risks, especially for AFib and the required entry into the left atrium from the right atrium. Over the years I've been cardioconverted with the electric shock/defibrillation, and have had a maze procedure done while I was open for other reasons. But, I always return to AFib, and I too have an enlarged atrium, left, it being 5.11 cm in diameter. I think anything over 4 cm is problematic, over 5 cm is out of business...there are no fixes in most cases.
More than your asked for I think, but sometimes it helps all just to talk about it.
Thanks for reply. I am currently with an Ep cardiologist. I am on meterolol 100 and flecanide. When I had afib last week I was off flecanide per dr orders. But I am still having arrythmias. I'm just not sure which one. It's not the same as last week. Since I got out of the hospital I have not seen my dr. My appt isn't until April 7. And it feels like a life time for me. I'm tired short of breath at times and chest hurts from time to time.
Doc says since I'm under 50 and echo was good in august that the svt and skipped beats are fine. But he told me that before I went to hospital last weekend.
Should I try to move up that appt? Or should it be fine?
If you have new or worse symptoms, you said you went to the hospital since you last talked with your EP, I think you have good reason to notify your EP/doctor that your condition has worsened and you are worried about waiting until April for your next appointment.
Right before I had my ablation for a-fib and flutter I was passing out almost on a daily basis. I had a very rapid fib and flutter that was called "1 to 1 conduction". This would make my heart rate go over 300.