Hello, Thank you for your query. You seem to have orthostatic hypotension. Would you clarify a few things for me? *what heart problems do you have? *what do you mean by low blood pressure? Please mention values. *do you take any medications? Any recent changes in prescription *have you made any diet changes? *how is your urine in quantity and color? *how long does the light headedness last? *any tinnitus (ringing in the ears), nausea, sweating during these episodes? *does it occur more often when you are on an empty stomach? Orthostatic hypotension is when your body doesn t adjust to changes in pressure adequately during a change in body position. This can happen as age advances, in dehydration, those who have certain heart condition or take certain medications. All these can alter the way our body adjusts to different pressures and position. I recommend : -a consult with your cardiologist and physician -blood tests (complete blood count, Thyroid stimulating hormone, electrolyte levels, blood glucose panel, HBA1C ). -multiple blood pressure readings in different positions (lying down, sitting and standing and on both arms) -an electrocardiogram and echocardiogram. Based on these we can arrive at a diagnosis. I suggest: -gradual change in posture. If lying down, turn to one side (stay in this position for 30 seconds), the gradually sit up (another 30 seconds), then slowly stand up (30 seconds) then begin to walk. -please consult your doctor ASAP. Hope this helps. Please let me know if there is anything else I can help you with. Wish you good health