CHEST PAIN. Accounts for 5% of all ED visits per yearDifferential diagnosis is extensive. CHEST PAIN. ANATOMYDIFFERENTIAL DIAGNOSISBRIEF OVERVIEW OF DISEASE PROCESSES CAUSING CHEST PAINAPPROACH TO CHEST PAIN. ANATOMY. In devising a differential diagnosis for chest pain, it becomes essential to review the anatomy of the thorax. The various components of the thorax can all be responsible for producing chest pain.