1. Dr. Zahoor 1

2. A 26 year old woman presents to the ER complaining of sudden onset of palpitations and severe shortness of breath and coughing. She reports that she experienced several episodes of palpitations in the past, often lasting a day or two, but never with dyspnea like this. She has a history of rheumatic fever at the age of 14 years. She is now 20 weeks pregnant with her first child and takes prenatal vitamins. She denies use of any other medications, tobacco and alcohol. 2

3. On examination, her heart rate is between 110 and 150 bpm and is irregularly irregular, with blood pressure of 92/65mmHg, respiratory rate of 24 breaths per minute and oxygen saturated of 94% on room air. She appears uncomfortable with laboured respirations. She is coughing, producing scant amounts of frothy sputum with pinkish tint. She has ruddy cheeks and a normal jugular venous pressure. She has bilateral inspiratory crackles in the lower lung fields. 3

4. On cardiac examination, her heart rhythm is irregularly irregular with a loud S 1, and low pitched diastolic murmur at the apex. Her apical impulse is nondisplaced. Her uterine fundus is palpable at the umbilicus, and she has no peripheral edema. An ECG is obtained: 4

5. 1. What is the most likely diagnosis? 2. What is your next step? 5

6. 1. Atrial fibrillation caused by mitral stenosis 2. Cardiac rate control with intravenous beta blockers 6

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