What could cause difficulties with a cardiac perfusion scan?

Variable entities: Some difficulties with a perfiusion scan can cause the quality of the scan to be diminshed, thus reducing its predictive ability. These include motion artifact, rapid heart rates or disrhythmias such as atrial fibrillation. Certain body habitus, for example very obese, a high riding diaphram or large pendulous breats can also cuase artifacts and affect test results.

Movement: Am unclear as to your question, but if i understand right, then moving during the scan would cause problems. Not removing a bra containing wires could cause problems. Severe claustrophobia can also cause problems.