Sir I had 2 sudden loss of unconsciousness, , first one in 2004 with sharp pain in hands and felling on the floor losing unconsciousness and second time in 2006 with flashing images in eyes continuously and at last felling unconsciousness , in both the cases I had woken up after some time and had pain all over the body with big deep breaths for some time and I had MRI, CT scan, EMT, every thing but could not find any reason.i smoke in that period from 1997 to 2006 heavily so please tell me what was the reason.last 4 years back I am taking blood pressure medication