This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
Swan Ganz catheter is used for what ? 
Select and explain. 
A. LV filling pressure, B. Pulmonary capillary pressure, C. Pulmonary aery occlussion pressure, D. saturation in mixed venous blood
A: LV filling pressure
Answer: A: LV filling pressure 
Explanation: Positioning of a balloon flotation (Swan-Ganz) catheter in the pulmonary aery permits monitoring of LV filling pressure; this technique is useful in patients who exhibit hypotension and/or clinical evidence of CHF. Cardiac output can also be determined with a pulmonary aery catheter. There is controversy regarding the use of pulmonary aery (Swan-Ganz) catheters in patients with established or suspected CS . Their use is generally recommended for measurement of filling pressures and cardiac output to confirm the diagnosis and optimize the use of IV fluids, inotropic agents, and vasopressors in persistent shock . REF : Harrison&;s principle of internal medicine,20th edition,pg no.2234