Mr. B is a 50-year-old male who comes into the office complaining of sharp chest pain in his mid-sternum of 24 hour duration. The pain has been steady and radiates to his left arm, worsened by swallowing, deep breathing and relieved by sitting up or leaning forward. He notes occasional tightness in his chest but denies shortness of breath, cough or diaphoresis. He denies any association with eating. This is his first episode of chest pain, but he worries that he may be having a heart attack because his father died of an MI at the age of 62. Based on his history, your differential diagnoses would include: 1. acute MI 2. pericarditis 3. costrochrondritis 4. pleuritic pain 5. GERD