Did you possible intend PACs vs 'AVCs'? PACs are generally innocuous unless their burden exceeds about 3%, at which the cardiologist/electrophysiologist will want more frequent monitoring to see if there is a progression. Above 8%, it generally merits an intervention, often an ablation.

It sounds to me, based on your episodic experience as you describe them, that you are in a form of presyncope, but without the typical sensation that you are about to faint (or you simply forget later when you are more conscious that you actually were sensing it...). Atrial flutter is probably not the issue here as a heart in AFl usually wants to stay in AFl. Atrial fibrillation is a distinct possibility, as is supraventricular tachycardia. PACs and PVCs don't normally cause the sensations you describe, although we're each individuals with individual reactions to bodily functions/malfunctions.

If I were you, with everything you have related in your original post, including your cardiologist's apparent indifference, I would seek advice and diagnosis further afield. I think you need a 24/7 monitoring device and you should wear it probably for a full week while doing everything (and I do mean EVERYTHING) you do during a typical week with all its routines and cycles. You do not want to fall and injure yourself, certainly not hit your head on the floor....that's never good. Secondly, knowing what I know about heart arrhythmias after years of learning, I would ask a ('nuther) cardiologist if you shouldn't be on a DOAC...just in case (Direct Oral Anti-Coagulant). If it turns out to be AF, there is a generally unacceptable risk of stroke due to blood pooling and 'going stale' in the left atrial appendage (LAA), a small grotto-like space at upper left of the left atrium. If that blood stagnates and begins to clot while you are in AF, the return to NSR will possibly/often dislodge the clot and it will be pumped into the left ventricle and up the aorta to be sent to some place where it will cause a loss of blood supply and result in local tissue death. In the heart, the lungs, or in the brain.............................................