A 60-year-old man comes to the physician because of progressive shortness of breath for 2-hour. The dyspnea occurs on moderate exertion and during the night; he sometimes wakes up coughing and "gasping for air." He has also had several episodes of heart pounding. Two weeks ago, he had a runny nose and a productive cough. He has type 2 diabetes mellitus and peripheral arterial disease. He has never smoked. He drinks one to two beers occasionally. He has a history of intravenous illicit drugs use but has not used in over 25 years. Current medications include aspirin, atorvastatin, and metformin. Blood pressure is 98/60 mm Hg and pulse is 112/min and regular. A short systolic murmur is heard at the apex. Bilateral crackles are present on lung auscultation. Bedside echocardiography reveals a flail posterior mitral leaflet due to chordal rupture and severe mitral regurgitation. Which of the following best reflects this patient's left ventricular hemodynamics compared to the normal heart?

Question

A 60-year-old man comes to the physician because of progressive shortness of breath for 2-hour. The dyspnea occurs on moderate exertion and during the night; he sometimes wakes up coughing and "gasping for air." He has also had several episodes of heart pounding. Two weeks ago, he had a runny nose and a productive cough. He has type 2 diabetes mellitus and peripheral arterial disease. He has never smoked. He drinks one to two beers occasionally. He has a history of intravenous illicit drugs use but has not used in over 25 years. Current medications include aspirin, atorvastatin, and metformin. Blood pressure is 98/60 mm Hg and pulse is 112/min and regular.  A short systolic murmur is heard at the apex.  Bilateral crackles are present on lung auscultation.  Bedside echocardiography reveals a flail posterior mitral leaflet due to chordal rupture and severe mitral regurgitation.  Which of the following best reflects this patient's left ventricular hemodynamics compared to the normal heart?

Quizplus · Accepted Answer

Eductional Objective: Regurgitant flow into the left atrium in acute mitral regurgitation leads to increased left atrial pressure and increased left ventricular end-diastolic volume (preload).  The low-resistance regurgitant pathway also decreases left ventricular afterload with a resulting increase in ejection fraction but overall decrease in forward stroke volume.  Increased left atrial pressure and decreased cardiac output result in pulmonary edema and severe hypotension, respectively.

A 60-Year-Old Man Comes to the Physician Because of Progressive