Valvular Heart Disease USMLE Step 1 Practice Question
A 45-year-old woman with a history of chronic mitral regurgitation presents to the emergency department with acute onset dyspnea, orthopnea, and pink frothy sputum. She reports palpitations that began 6 hours ago. Vital signs show blood pressure 145/92 mmHg, heart rate 142 bpm and irregularly irregular, respiratory rate 28/min, and oxygen saturation 88% on room air. Cardiac examination reveals a holosystolic apical murmur, prominent S3 gallop, and bibasilar crackles. An ECG shows atrial fibrillation with a rapid ventricular response. Chest X-ray demonstrates bilateral pulmonary edema with an enlarged cardiac silhouette. Which of the following best explains this patient's acute decompensation?
Answer choices
- AAcute myocardial infarction with papillary muscle rupture
- BAcute atrial fibrillation with rapid ventricular responseCorrect answer
- CSpontaneous rupture of the chordae tendineae
- DAcute development of mitral stenosis
- EAortic valve endocarditis with aortic regurgitation
- FMechanical failure of a prosthetic mitral valve
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