A 59-year-old man is brought to the emergency department by his wife because of a 3-day history of worsening shortness of breath. He has a history of long-standing hypertension, type 2 diabetes mellitus, and gout. Current medications include enalapril, amlodipine, metformin, and ibuprofen as needed. His wife reports that he only takes his medications every second or third day. He has smoked one pack of cigarettes daily for 30 years. He stopped drinking alcohol after his first acute gout attack 3 years ago. His temperature is 37.1°C (98.9°F), pulse is 86/min, and blood pressure is 167/95 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 91%. There is pitting edema in the bilateral lower extremities. Levels of which of the following substances will be higher in the pulmonary vein compared to the pulmonary artery in this patient?

Question

A 59-year-old man is brought to the emergency department by his wife because of a 3-day history of worsening shortness of breath. He has a history of long-standing hypertension, type 2 diabetes mellitus, and gout. Current medications include enalapril, amlodipine, metformin, and ibuprofen as needed. His wife reports that he only takes his medications every second or third day. He has smoked one pack of cigarettes daily for 30 years. He stopped drinking alcohol after his first acute gout attack 3 years ago. His temperature is 37.1°C (98.9°F), pulse is 86/min, and blood pressure is 167/95 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 91%. There is pitting edema in the bilateral lower extremities.  Levels of which of the following substances will be higher in the pulmonary vein compared to the pulmonary artery in this patient?

Quizplus · Accepted Answer

Eductional Objective: The reduced cardiac output in heart failure leads to decreased renal perfusion and consequent stimulation of the renin-angiotensin-aldosterone system in a maladaptive effort to maintain effective blood volume.  Inactive angiotensin I is converted into active angiotensin II by endothelial-bound angiotensin-converting enzyme in the lungs.

A 59-Year-Old Man Is Brought to the Emergency Department by His