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Potassium of 7.5 is surely high .High potassium is not good
for heart;but reports are a supportive evidence along with symptom to diagnose the disease a person is suffering from.You had some problem or symptom for which i guess you got investigated also you have not written any details about your age;sex;or the disease or problem you have .If the other reports are normal then please ask your doctor
whether increase in potassium has any relation with your symptoms
as he will be the better person to give opinion.