Artifacts seem to have different meanings in different cardiology departments. My second echo scan had a circular blur on the image which couldn't be focused no matter how much they tried. She referred to this as an artifact, an anolomy which would be later investigated. However, later scans had no problems and there was nothing there.
I don't know what the term artifact means in a nuclear scan but I agree with Jon, it is probably an imaging system glitch.
When I had my second set of my 2 part nuclear scans I had a scarey experience. The first scan I had the xray device over the top of my chest, virtually in line with my chin.
The second scan was done by a different operator, and it was further down, by about 5 inches. I commented on the difference but was just told "lay still and no talking".
They checked the images afterwards and the bottom of my heart was missing. Now, it took a couple of seconds for the penny to drop, but in those few seconds I can tell you I felt my heart nearly burst out of my chest. They did a second attempt with the scanner higher up and my heart was complete after all.
Gladys,
The 71% is your EF% which is normal, nothing to worry about there. The "small defect that may be an artifact" means that there was a small area of your heart that showed no tracer uptake meaning that there may be some damaged heart cells from on old MI. Before you panic, it is more likely that it was due to soft tissue attenuation which simply means that part of your heart did not x-ray well due to the soft tissue that the x-ray was taken through, this is fairly common. Did your doctor say anything about this? I would ask your doctor to explain what was seen and his interpretation of it.
Hope this helps,
Jon