A 50-year-old woman presented with fatigue and shortness of breath. One week before presentation, she experienced the gradual onset of dyspnea after moderate exertion, profound malaise, and a non-productive cough. In the 48 hours before admission, her shortness of breath worsened, such that she was dyspneic while at rest. She reported palpitations, nausea, and bilious emesis . . .