Is it possible to have 1 or more 80-90% blocked artery to or from heart and still have a 'normal' heart? will stress test show blockage? treatment?

Hear Disease: It does sound like a blockage that large be normal. First it depends on the location of the artery, what part of the heart it irrigates. Sress thallium should show the blockage and definetely a cardia catherization would allow for diagnos and treatment.,

"Normal?": If by "normal" you mean can the heart pump function still be normal then the answer is yes! Usually some form of stress test would pick such a condition up but not always. The most sensitive test for fiinding out the exact details you described above would be an arteriogram or angiogram. With this test a small tube is inserted in the arm or leg and dye injected directly into the heart vessels.

See answer below:: Stress test would show this abnormality. Next step would be cardiac catheterization. Coronary artery bypass is a potential treatment if severe. Medications like aspirin and cholesterol lowering medications are recommended in people with coronary artery disease.

No: If there is a definitively diagnosed blockage then the person does not have a normal heart. Person gets the diagnosis of Coronary Artery Disease and will need treatment and prevention of further blockages. Other treatment besides bypass include angioplasty/stenting of blockage depending on location of the blockage. Prevention includes medicine to lower cholesterol, Aspirin, quitting smoking.