I am 67 years old, very fit (swim, ride horses, work on a ranch), and I have low blood pressure normally and sometimes low pulse rate (30 resting at night). My heart rate goes up when i am active and i am never dizzy. I have had the treadmill test and a 24 hour heart monito about 2 years ago.
Today I was dizzy in bed twice, then again about an hour later and spells persisted for a couple of hours. My husband is a veterinarian and i have a pulse rates between 40 and 52 beat a minute resting. I feel fine now. Beat is irregular.