Could heart mri detect breast cancer?

Yes: It's possible that breast cancer could be detected on a heart mri, depending on whether the breasts were included in the images. However, the radiologist reading the heart MRI is not looking for breast cancer, so even if it's there it's very likely to be missed. But if a radiology report mentions a breast abnormality, your doctor needs to know right away!

Possible: It is possible for an abnormal area in the breast to show up on a heart mri. If this is the case, then a mammogram and possibly a breast MRI should be performed. If an abnormality is seen then a biopsy should be preformed.I recommend getting evaluated by a breast surgeon.

It is: possible, but a cardiac MR is not optimized for breast evaluation, so breast cancer detection on cardiac MR is likely to be accidental and imprecise. It cannot substitute for the standard breast imaging techniques such as mammography, sonography, and breast MR.