Did he smoke?Poor circulation sounds like he has some trouble with his arteries. You don't state what he died of. He could have died of many things related to the poor condition of his arteries or to do with his operation.Cardiovascular disease is a broad category of diseases to do with the heart and the blood vessels. The one thing they have in common is the wear and tear and inflammation of the blood vessels (atherosclerosis - hardening of the arteries).Risk factors for these sorts of diseases include

iabetes (you mentioned that he is NOT a diabetic)High blood pressureCigarette SmokingHigh CholesterolFamily History (your brother counts if he is immediate family to you - strike 1 already?)These and many other factors combine to cause inflammatory changes in the insides of the arteries and a build up of a fatty plaque.This accumulation can lead to narrowing of the arteries and so lead to less blood getting to the cells at the end of the artery - like in your brother's case the big toe. This is called Peripheral Vascular Disease.However, if this artery is one that supplies the heart, then the patient is in for a tough time. This condition can then lead to heart attacks or angina chest pains.Heart attacks can kill you, of course.Other bad things can happen depending on which artery is affected.Arteries to the brain: strokeAorta: abdominal aortic aneurysm
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