An 87-year-old woman with a history of scleroderma treated with methotrexate presented with respiratory distress. An electrocardiogram (ECG) was recorded on presentation (Figure 1). There were no prior ECGs available for comparison. She denied any previous cardiac history. On examination she was visibly dyspneic; blood pressure, 104/48 mm Hg; pulse, 106 bpm; and a room air oxygen saturation of 65% that quickly improved with nasal cannula oxygenation. Pulmonary examination revealed bilateral rales, and cardiac auscultation revealed distant heart sounds along the left precordium. The remainder of the examination findings were unremarkable.