Fentanyl is a synthetic opioid that’s 50-100 times stronger than the pain reliever morphine. While some people use fentanyl on purpose, many others get it in their systems without their knowledge.

Abnormal stress test results may suggest an underlying heart condition, such as coronary artery disease, or a blockage in the arteries supplying blood to the heart. Failing a stress test means you can ...

A nuclear stress test, also called myocardial perfusion imaging (MPI) or a thallium stress test, uses a radioactive tracer to show how blood flows through your heart muscles during exercise and at ...