Cath lab technicians also known as cardiac catheterization technologists are cardiovascular technologists who work in facilities that run tests on heart health. They assist with the insertion of catheters into the heart and are responsible for measuring and administering special fluids. These small tubes and fluids are used for tests to determine how well the heart is working. Tests include x-rays pressure checks and pumping strength evaluations. Works under the supervision of a physician and must monitor patients for life-threatening changes during a procedure. Some cath labs also support noninvasive heart health procedures. will use machines that help diagnose various conditions of the heart. Aside from invasive catheterization you might also use other machines. One machine the EKG will allow you to get a reading by attaching electrodes to a patients body and recording electrical variations of the heart.