During cardiac catheterization, a thin catheter is inserted into an artery and dye is injected to evaluate narrowing or occlusion of the coronary arteries and to measure blood pressure in the heart and oxygen in the blood.

• A. Lung volumes
• B. Narrowing or occlusion of the coronary arteries and measure blood pressure in the heart and oxygen in the blood
• C. Spinal alignment
• D. Abdominal aorta diameter

Answer: (B)

The main concept is using cardiac catheterization with coronary angiography to evaluate coronary artery disease and obtain intracardiac hemodynamics and oxygenation data. A thin catheter threaded into an artery allows contrast dye to be injected so the coronary arteries are visualized and any narrowing or occlusion is seen on imaging. Placing the catheter in the heart enables direct measurement of chamber pressures and collection of blood samples to determine oxygen content in each chamber, which helps assess cardiac function and detect issues like shunts or valve problems. This combination—visualizing coronary vessels and measuring pressures and oxygenation—matches the described procedure. Other options don’t fit because they relate to lung volumes, spinal alignment, or abdominal aorta diameter, not the coronary evaluation and intracardiac measurements performed in this procedure.