Yesterday I went to the ER for presyncope. I ve always had pvcs and I was told they were benign. Yesterday I was sitting and relaxing when I felt a hard beat, then no beat for several seconds, my vision blacked so I put my head between my legs, when I raised my head all I saw were starts. Er doctor said my potassium was a little low and sent me home. Everything I read on the internet says this could be a fatal heart arhythmia v should I be concerned? I have no history of heart disease myself but a strong family history of early onset heart disease. My blood pressure and cholesterol are good and I had a stress test 3 years ago that only showed an abnormal raise in blood pressure.