I always feel my afib, maybe because heart rate goes up to 180+. I had a seven hour episode last summer and am still not on meds. I have diltiazem at home but have only used it twice, when I had an episode. I have episodes about once a year. I always end up in ER (and last time ICU) because diltiazem lowers my already low blood pressure so they are careful. Still not on blood thinners. The last one was my longest and they did an echocardiogram to check for clots. My monitors did not show afib over 7-30 days.