What procedure used to collect diagnostic information about the cardiac structures by threading a thin tube into the heart?

The procedure used to collect diagnostic information about the cardiac structures by threading a thin tube into the heart is called cardiac catheterization. During this procedure, a catheter is inserted through a blood vessel, usually in the arm or leg, and guided to the heart. It allows for the measurement of pressures within the heart chambers, assessment of blood flow, and can also facilitate the collection of tissue samples or the performance of interventions like angioplasty. Cardiac catheterization is commonly used to diagnose and evaluate various heart conditions.