A Hidden Solution

A 51-year-old woman presented to the ER with a 6-month history of intermittent palpitations, which had worsened that day. She described her pulse as fast but regular. She also reported worsening fatigue, heat intolerance, and an 18-kg (40-lb) weight loss. Foreword In this Journal feature, information about a real patient is presented in stages (boldface type) to an expert clinician, who responds to the information, sharing his or her reasoning with the reader (regular type). The authors' commentary follows. Stage A 51-year-old woman presented to her local emergency room with a 6-month history of intermittent palpitations, which had worsened that day. She described her pulse as fast (it was approximately 140 beats per minute) but regular. She also reported recent worsening fatigue, heat intolerance, and an 18-kg (40-lb) weight loss despite a good appetite. She reported no dyspnea, orthopnea, syncopal episodes, headaches, tremors, or profuse sweating. She did not have a history of cardiovascular disease. Response The patient's pulse of 140 beats per minute is consistent with sinus tachycardia. The occurrence of palpitations in a relatively young woman without . . .