A 60-year-old woman presents with a chief complaint of uncomfortable breathing on exertion. She has had a minimally productive cough for several years that does not bother her. On further questionin g, she states that her breathing gets much worse when she lies down. The most likely cause of her dyspnea is: Cardiac 2. A 68-year-old male presents with a chief complaint of episodes of lightheadedness or dizziness. He states that sweating, tachycardia, and some hand trembling are often associated w...