A cardiac catheterization (or cardiac cath) is a procedure that examines how well your heart is functioning. To do so, a catheter, which is a thin hollow tube, is inserted into a large blood vessel (artery) that leads to your heart. This can be done through an artery in your groin area or your wrist. Your heart and artery anatomy can be assessed, using a small amount of “dye,” during the procedure. Depending on the cardiac cath findings, patients can be discharged home the same day.