Chest pain (or chest discomfort)
Chest pain (or chest discomfort) is a common symptom that can occur as a result of cardiovascular, pulmonary, pleural, or musculoskeletal disease, esophageal or other gastrointestinal disorders, herpes zoster, cocaine use, or anxiety states. The frequency and distribution of life-threatening causes of chest pain, such as acute coronary syndrome (ACS), pericarditis, aortic dissection, vasospastic angina, pulmonary embolism, pneumonia, and esophageal perforation, vary substantially between clinical settings.
Systemic lupus erythematosus, rheumatoid arthritis, reduced estimated glomerular filtration rate, and HIV infection are conditions that confer a strong risk of coronary artery disease. Precocious ACS may represent acute thrombosis independent of underlying atherosclerotic disease. In patients aged 35 years or younger, risk factors for ACS are obesity, hyperlipidemia, and smoking.
Causes of Acute Chest Pain
In a typical population of patients presenting for the evaluation of acute chest pain in EDs, about 15% to 25% have acute MI or unstable angina. A small percentage have other life-threatening problems, such as pulmonary embolism or acute aortic dissection, but most are discharged without a diagnosis or with a diagnosis of a non-cardiac condition. These non-cardiac conditions include musculoskeletal syndromes, disorders of the abdominal viscera (including gastroesophageal reflux disease), and psychological conditions
Myocardial Ischemia or Infarction
The most common serious cause of acute chest discomfort is myocardial ischemia or infarction, which occurs when the supply of myocardial oxygen is inadequate compared with the demand. Myocardial ischemia usually occurs in the setting of coronary atherosclerosis, but it may also reflect dynamic components of coronary vascular resistance. Coronary spasm can occur in normal coronary arteries or, in patients with coronary disease, near atherosclerotic plaques and in smaller coronary arteries
The classic manifestation of ischemia is angina, which is usually described as a heavy chest pressure or squeezing, a burning feeling, or difficulty breathing. The discomfort often radiates to the left shoulder, neck, or arm. It typically builds in intensity over a period of a few minutes. The pain may begin with exercise or psycho-logical stress, but ACS most commonly occurs without obvious precipitating factors.
Atypical descriptions of chest pain reduce the likelihood that the symptoms represent myocardial ischemia or injury. The American College of Cardiology (ACC) and American Heart Association (AHA) guidelines list the following as pain descriptions that are not characteristic of myocardial ischemia
- Pleuritic pain (i.e., sharp or knifelike pain brought on by respiratory movements or cough)
- Primary or sole location of discomfort in the middle or lower abdominal region
- Pain that may be localized at the tip of one finger, particularly over the left ventricular apex
- Pain reproduced with movement or palpation of the chest wall or arms
- Constant pain that persists for many hours
- Very brief episodes of pain that last a few seconds or less
- Pain that radiates into the lower extremities
The visceral surface of the pericardium is insensitive to pain, as is most of the parietal surface. Therefore, noninfectious causes of pericarditis (e.g., uremia) usually cause little or no pain. In contrast, infectious pericarditis almost always involves surrounding pleura, so that patients typically experience pleuritic pain with breathing, coughing, and changes in position.
Swallowing may induce the pain because of the proximity of the esophagus to the posterior heart. Because the central diaphragm receives its sensory supply from the phrenic nerve, and the phrenic nerve arises from the third to fifth cervical segments of the spinal cord, pain from infectious pericarditis is frequently felt in the shoulders and neck.
Acute aortic dissection usually causes the sudden onset of excruciating ripping pain, the location of which reflects the site and progression of the dissection. Ascending aortic dissections tend to manifest with pain in the midline of the anterior chest, and posterior descending aortic dissections tend to manifest with pain in the back of the chest. Aortic dissections are rare, with an estimated annual incidence of 3/100,000, and usually occur in the presence of risk factors including Marfan and Ehlers-Danlos syndromes, bicuspid aortic valve, pregnancy (for proximal dissections), and hypertension (for distal dissections).
Pulmonary conditions that cause chest pain usually produce dyspnea and pleuritic symptoms, the location of which reflects the site of pulmonary disease. Tracheobronchitis tends to be associated with a burning midline pain, whereas pneumonia can produce pain over the involved lung. The pain of a pneumothorax is sudden in onset and is usually accompanied by dyspnea. Primary pneumothorax typically occurs in tall, thin young men; secondary pneumothorax occurs in the setting of pulmonary disease such as chronic obstructive pulmonary disease, asthma, or cystic fibrosis. Asthma exacerbations can present with chest discomfort, typically characterized as tightness
Irritation of the esophagus by acid reflux can produce a burning dis-comfort that is exacerbated by alcohol, aspirin, and some foods. Symptoms often are worsened by a recumbent position and relieved by sitting upright and by acid-reducing therapies. Esophageal spasm can produce a squeezing chest discomfort similar to that of angina.
Mallory-Weiss tears of the esophagus can occur in patients who have had prolonged vomiting episodes. Severe vomiting can also cause esophageal rupture (Boerhaave syndrome) with mediastinitis. Chest pain caused by peptic ulcer disease usually occurs 60 to 90 minutes after meals and is typically relieved rapidly by acid-reducing therapies. This pain is usually epigastric in location but can radiate into the chest and shoulders.
Musculoskeletal and Other Causes
Chest pain can arise from musculoskeletal disorders involving the chest wall, such as costochondritis, by conditions affecting the nerves of the chest wall, such as cervical disc disease, by herpes zoster, or following heavy exercise. Musculoskeletal syndromes causing chest pain are often elicited by direct pressure over the affected area or by movement of the patient’s neck. The pain itself can be fleeting, or can be a dull ache that lasts for hours. Panic syndrome is a major cause of chest discomfort in ED patients. The symptoms typically include chest tightness, often accompanied by shortness of breath and a sense of anxiety, and generally last 30 minutes or longer.
Unless a competing diagnosis can be confirmed, an ECG is warranted in the initial evaluation of most patients with acute chest pain to help exclude ACS. ST-segment elevation is the ECG finding that is the strongest predictor of acute myocardial infarction; however, up to 20% of patients with ACS can have a normal ECG.
Clinically stable patients with cardiovascular disease risk factors, normal ECG, normal cardiac biomarkers, and no alternative diagnoses (such as typical GERD or costochondritis) should be followed up with a timely exercise stress test that includes perfusion imaging. However, more than 25% of patients with stable chest pain referred for noninvasive testing will have normal coronary arteries and no long-term clinical events. The ECG can also provide evidence for alternative diagnoses, such as pericarditis and pulmonary embolism.
Chest radiography is often useful in the evaluation of chest pain, and is always indicated when cough or shortness of breath accompanies chest pain. Findings of pneumomediastinum or new pleural effusion are consistent with esophageal perforation. Stress echocardiography is useful in risk stratifying patients with chest pain, even among those with significant obesity.
Panic disorder is a common cause of chest pain, accounting for up to 25% of cases that present to emergency departments and a higher proportion of cases presenting in primary care office practices. Features that correlate with an increased likelihood of panic disorder include absence of coronary artery disease, atypical quality of chest pain, female sex, younger age, and a high level of self-reported anxiety. Depression is associated with recurrent chest pain with or without coronary artery disease
Treatment of chest pain should be guided by the underlying etiology. The term “non-cardiac chest pain” is used when a diagnosis remains elusive after patients have undergone an extensive workup. Almost half reported symptom improvement with high-dose proton-pump inhibitor therapy.
It is unclear whether tricyclic or selective serotonin reuptake inhibitor antidepressants have benefit in non-cardiac chest pain. Hypnotherapy may offer some benefit.