Outpatient diagnosis of acute chest pain in adults.

Approximately 1 percent of primary care office visits are for chest pain, and 1.5 percent of these patients will have unstable angina or acute myocardial infarction. The initial goal in patients presenting with chest pain is to determine if the patient needs to be referred for further testing to rule in or out acute coronary syndrome and myocardial infarction. The physician should consider patient characteristics and risk factors to help determine initial risk. Twelve-lead electrocardiography is typically the test of choice when looking for ST segment changes, new-onset left bundle branch block, presence of Q waves, and new-onset T wave inversions. For persons in whom the suspicion for ischemia is lower, other diagnoses to consider include chest wall pain/costochondritis (localized pain reproducible by palpation), gastroesophageal reflux disease (burning retrosternal pain, acid regurgitation, and a sour or bitter taste in the mouth), and panic disorder/anxiety state. Other less common but important diagnostic considerations include pneumonia (fever, egophony, and dullness to percussion), heart failure, pulmonary embolism (consider using the Wells criteria), acute pericarditis, and acute thoracic aortic dissection (acute chest or back pain with a pulse differential in the upper extremities). Persons with a higher likelihood of acute coronary syndrome should be referred to the emergency department or hospital.