Cardiac catheterization has been historically the most important procedure performed by a cardiologist to assess heart disease. In the early days of cardiology, it was performed to assess various kinds of congenital and valvular heart disease. Today it is the most commonly performed invasive cardiac procedure. It can be safely performed either through a radial artery access in your wrist or a femoral artery access through your groin. Venous catheterization can also be useful to introduce a Swan-Ganz (Pulmonary Artery) catheter to accurately assess pulmonary artery pressures. In conjunction with left heart catheterization it is a very important tool in understanding the functioning of the heart, its valves and its overall performance. Cardiac catheterization also can include coronary angiography which is a procedure to assess the three main arteries that supply blood to the heart. Significant obstruction in these arteries can cause chest pain (angina) or a heart attack. Coronary artery disease is the most common cause of death related to heart disease.