A 75-year-old man is brought to the emergency department 20 minutes after he lost consciousness. He was playing with his 3-year-old granddaughter when he suddenly collapsed and was unresponsive. He has had episodes of mild chest pain and dyspnea for the past 2 months, especially while working on his car. He has hypertension treated with hydrochlorothiazide. Examination shows a grade 3/6 late systolic murmur at the right sternal border that radiates to the carotids. His blood pressure is 90/60 mm Hg and his heart rate is 130/min with an irregularly irregular rhythm. Electrocardiogram shows new-onset atrial fibrillation without significant ST-segment or T-wave changes. Chest x-ray shows bilateral pulmonary edema. Which of the following hemodynamic changes is most likely associated with this patient's current presentation?

Question

A 75-year-old man is brought to the emergency department 20 minutes after he lost consciousness. He was playing with his 3-year-old granddaughter when he suddenly collapsed and was unresponsive. He has had episodes of mild chest pain and dyspnea for the past 2 months, especially while working on his car. He has hypertension treated with hydrochlorothiazide. Examination shows a grade 3/6 late systolic murmur at the right sternal border that radiates to the carotids. His blood pressure is 90/60 mm Hg and his heart rate is 130/min with an irregularly irregular rhythm.  Electrocardiogram shows new-onset atrial fibrillation without significant ST-segment or T-wave changes.  Chest x-ray shows bilateral pulmonary edema.  Which of the following hemodynamic changes is most likely associated with this patient's current presentation?

Quizplus · Accepted Answer

Eductional Objective: In patients with chronic aortic stenosis and concentric left ventricular hypertrophy, atrial contraction contributes significantly to left ventricular filling.  Loss of atrial contraction due to atrial fibrillation can reduce left ventricular preload and cardiac output sufficiently to cause systemic hypotension.  Decreased forward filling of the left ventricle can also result in backup of blood in the left atrium and pulmonary veins, leading to acute pulmonary edema.

A 75-Year-Old Man Is Brought to the Emergency Department 20