Pulmonary Embolism (See also Chap. 256) Chest pain due to pulmonary embolism is believed to be due to distention of the pulmonary artery or infarction of a segment of the lung adjacent to the pleura. Massive pulmonary emboli may lead to substernal pain that is suggestive of acute myocardial infarction. More commonly, smaller emboli lead to focal pulmonary infarctions that cause pain that is lateral and pleuritic. Associated symptoms include dyspnea and, occasionally, hemoptysis. Tachycardia is usually present. Although not always present, certain characteristic ECG changes can support the diagnosis. Pneumothorax (See also Chap. 257) Sudden onset of pleuritic chest pain and respiratory. | Chapter 013. Chest Discomfort Part 4 Pulmonary Embolism See also Chap. 256 Chest pain due to pulmonary embolism is believed to be due to distention of the pulmonary artery or infarction of a segment of the lung adjacent to the pleura. Massive pulmonary emboli may lead to substernal pain that is suggestive of acute myocardial infarction. More commonly smaller emboli lead to focal pulmonary infarctions that cause pain that is lateral and pleuritic. Associated symptoms include dyspnea and occasionally hemoptysis. Tachycardia is usually present. Although not always present certain characteristic ECG changes can support the diagnosis. Pneumothorax See also Chap. 257 Sudden onset of pleuritic chest pain and respiratory distress should lead to consideration of spontaneous pneumothorax as well as pulmonary embolism. Such events may occur without a precipitating event in persons without lung disease or as a consequence of underlying lung disorders. Pneumonia or Pleuritis See also Chaps. 251 and 257 Lung diseases that damage and cause inflammation of the pleura of the lung usually cause a sharp knifelike pain that is aggravated by inspiration or coughing. Gastrointestinal Conditions See also Chap. 286 Esophageal pain from acid reflux from the stomach spasm obstruction or injury can be difficult to discern from myocardial syndromes. Acid reflux typically causes a deep burning discomfort that may be exacerbated by alcohol aspirin or some foods this discomfort is often relieved by antacid or other acid-reducing therapies. Acid reflux tends to be exacerbated by lying down and may be worse in early morning when the stomach is empty of food that might otherwise absorb gastric acid. Esophageal spasm may occur in the presence or absence of acid reflux and leads to a squeezing pain indistinguishable from angina. Prompt relief of esophageal spasm is often provided by antianginal therapies such as sublingual nifedipine further promoting confusion between these syndromes. Chest pain can
