A 55-yeаr-оld mаn cоmplаins оf in the Manubrium area of his chest, which he describes as "ripping" in nature. He tells you that the pain began suddenly and has been intense and unrelenting since its onset. His medical history includes hypertension, and he admits to being noncompliant with his antihypertensive medication. Which of the following assessment findings would MOST likely reinforce your suspicion regarding the cause of his pain?