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The heart, lungs, esophagus, and great vessels provide afferent visceral input through the same thoracic autonomic ganglia. A painful stimulus in these organs is typically perceived as originating in the chest, but because afferent nerve fibers overlap in the dorsal ganglia, thoracic pain may be felt anywhere between the epigastrium and the jaw, including the arms or shoulders (as referred pain). Painful stimuli from thoracic organs can produce discomfort described as pressure, gas, burning, aching, and sometimes sharp pain. Because the sensation is visceral in origin, many patients deny they are having pain and insist it is merely discomfort.
Etiology
Many disorders produce chest pain or discomfort. Some (eg, acute MI, unstable angina, thoracic aortic dissection, tension pneumothorax, esophageal rupture, pulmonary embolism) are immediately life threatening. Some (eg, angina pectoris, pericarditis, myocarditis, pneumothorax, pneumonia, pancreatitis, various thoracic malignancies) are potentially life threatening. Others (eg, gastroesophageal reflux disease [GERD], peptic ulcer, esophageal motility disorders, costochondritis, chest trauma, biliary tract disease, herpes zoster) are uncomfortable but usually not dangerous.
Chest pain in children and young adults (< 30 yr) is less likely to result from myocardial ischemia, although MI can occur in people in their 20s. Musculoskeletal or pulmonary disorders are more common causes in these age groups.
Evaluation
History:
Location, duration, character, and quality of the pain and triggering and relieving factors are important. Past cardiac disorders, use of drugs that can trigger coronary artery spasm (eg, cocaine, triptans, phosphodiesterase inhibitors), and presence of risk factors for coronary artery disease (CAD) or pulmonary embolism (eg, leg pain or injury, recent immobilization, travel, pregnancy) may be important. The presence or absence of risk factors for CAD (eg, hypertension, hypercholesterolemia, smoking, positive family history) alters the probability of underlying CAD but does not help diagnose the cause of acute chest pain.
Symptoms due to serious thoracic disorders overlap and vary greatly, but distinctions can sometimes be made. Crushing pain radiating to the jaw or arm suggests acute ischemia or MI. Patients often ascribe myocardial ischemic pain to indigestion. Exertional pain relieved by rest indicates angina pectoris. Tearing pain radiating to the back suggests thoracic aortic dissection. Burning pain radiating from epigastrium to throat, exacerbated by lying down and relieved by antacids, suggests GERD. Fever, chills, and cough suggest pneumonia. Significant dyspnea suggests pulmonary embolism or pneumonia.
Pain can be exacerbated by respiration, movement, or both in serious or minor disorders; these triggers are not specific. Brief (< 5 sec), sharp, intermittent pains rarely result from serious disorders.
Physical examination:
Although not specific, tachycardia, bradycardia, tachypnea, hypotension, or signs of hypoperfusion (eg, confusion, ashen color, diaphoresis) increase the likelihood of a serious underlying disorder.
Unilateral absence of breath sounds suggests pneumothorax; resonance to percussion and dilated neck veins suggest tension pneumothorax. Fever and rales suggest pneumonia. Fever alone may be due to pulmonary embolism, pericarditis, acute MI, or esophageal rupture. Pericardial rub suggests pericarditis. The 4th heart sound (S4), late systolic murmur of papillary muscle dysfunction, or both suggest MI. Focal CNS abnormalities, an aortic regurgitant murmur, or marked asymmetry in pulse or BP between arms suggests thoracic aortic dissection. Leg swelling and tenderness suggest deep venous thrombosis and thus possible pulmonary embolism. Tenderness of the chest to palpation, present in about 15% of patients with acute MI, is not specific for origin of pain in chest wall.
Testing:
For anyone with chest pain, minimal testing includes pulse oximetry, ECG, and chest x-ray. For adults, blood tests for cardiac markers are often done. Results of these tests should be integrated with findings from the history and physical examination, and specific diagnoses should be pursued. Blood tests are not valuable as a primary screen. In particular, a single normal set of cardiac markers should not be used to rule out a cardiac cause. If myocardial ischemia is likely, tests should include serial measurement of cardiac markers and ECGs and possibly stress ECG or a stress imaging test (see Coronary Artery Disease: Stress testing).
A diagnostic trial of sublingual nitroglycerin or an oral liquid antacid does not adequately differentiate myocardial ischemia from GERD or gastritis. Either drug may relieve symptoms of either disorder.
Treatment:
Specific identified disorders are treated. If etiology is not clearly benign, patients are usually admitted to the hospital or an observation unit for cardiac monitoring and more extensive evaluation. Symptoms are treated with acetaminophen or opioids as needed, pending a diagnosis.
Last full review/revision November 2005
Content last modified November 2005
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