Right heart catheterization provides which measurements not typically obtained from standard left heart cath?

• A. Right-sided pressures (RA/RV/PA)
• B. Left atrial pressure
• C. Coronary artery anatomy
• D. Aortic root size

Answer: (A)

Right heart catheterization is used to directly measure pressures on the venous side of the circulation—the right atrium, right ventricle, and pulmonary artery. These right-sided pressures reflect venous return, right heart filling, and the pressure the right heart must pump against. A standard left heart catheterization, performed via arterial access, is aimed at left-sided hemodynamics and coronary anatomy: it provides left atrial or left ventricular pressures (often directly in the LV) and images of the coronary arteries as well as the aorta. Because the left-sided study does not routinely access the right heart or pulmonary vasculature, direct measurements of RA/RV/PA pressures are not typically obtained during a standard left heart cath. (Note: a wedge pressure from a pulmonary artery catheter can estimate left atrial pressure, but that requires right heart catheterization with a PA approach, not a routine left heart study.) Therefore, the measurements not typically obtained from a standard left heart cath are the right-sided pressures.