Atypical Chest Pain
Thomas J. Hansen
I. BACKGROUND. “Typical” chest pain is pain that is typical of anginal pain. This pain is usually described as substernal, radiating to the left neck and arm, and is pressure like or has a squeezing sensation. “Atypical” chest pain is defined as the absence of this typical presentation.
II. PATHOPHYSIOLOGY. Atypical chest pain can originate in any of the thoracic organs, as well as from extrathoracic sources (e.g., thyroiditis or panic disorder).
III. EVALUATION. The approach to the evaluation of acute chest pain, whether typical or atypical, should be to rapidly assess whether the pain is due to cardiac disease. Atypical chest pain does not rule out an acute myocardial infarction (AMI), especially in women
(1), patients with diabetes, and the elderly, in whom an AMI may present in an atypical fashion. A clinical history of the chest pain and an electrocardiogram (ECG) should be obtained within 5 minutes after presentation
(2). The ECG is critical for guiding initial therapy and decisions regarding diagnosis and treatment.
A. History.
The clinical history should focus on the time of onset, the characteristic of the pain, the location (retrosubsternal, subxiphoid, diffuse), the frequency of the pain (constant, intermittent, acute onset), the duration of the pain, precipitating factors (exertion, stress, food, respiration, movement), the quality of the pain (burning, squeezing, dull, sharp, tearing, heavy), and any associated symptoms (shortness of breath, diaphoresis, nausea, vomiting, jaw pain, back pain, radiation, palpitations, weakness, fatigue).
Other pertinent questions include assessing risk factors for coronary artery disease (diabetes, smoking, hypertension, hypercholesteremia, family history), anorexia, anxiety, cough and/or wheezing, drug use, fever, previous history of deep vein thrombosis or pulmonary embolism, pain increased with recumbency or relieved by leaning forward, presence of a mass, lesion, or rash on the chest, previous history of cancer, pregnancy/postpartum, oral contraceptive use, or trauma, relationship of pain with eating, and syncopal or near-syncopal episodes.
B. Physical examination.
The physical examination should include a rapid assessment of vital signs, as well as oxygen saturation and electrocardiographic evaluation. Following this, an examination of the chest should be performed. Cardiac examination should focus on pericardial rubs, systolic and diastolic murmurs, third or fourth heart sounds, and distended jugular veins. Auscultation of the lungs should focus on diminished breath sounds, a pleural rub, rales, rhonchi, and wheezes. Examination of the legs should focus on edema and poor perfusion of a limb, which may indicate an aortic dissection. Examination of the musculoskeletal system should focus on reproducible or localized pain. Examination of the skin should assess for lesions, masses, or rashes.
C. Testing
1. Oxygen saturation. Oxygen saturation below 92% may indicate a myocardial infarction, spontaneous pneumothorax, pulmonary embolism, or pneumonia. An arterial blood gas is warranted.
2. ECG. Always compare with an old ECG when available. The presence of T wave inversion is consistent with myocardial ischemia. ST elevation is consistent with myocardial injury, and ST depression is consistent with subendocardial infarction. A Q wave is diagnostic of a myocardial infarction (3). A pulmonary embolism is classically associated with the S1Q3T3 pattern, representing a large S wave in I, an ST depression in II, and a large Q wave in III with T wave inversion. Sensitivity of this is less than 20%, however. Acute pericarditis demonstrates diffuse ST-segment elevation, in which the ST segment is flat or slightly concave, and PR depression.
3. Other laboratory tests
a. Comprehensive metabolic profile. Used to detect metabolic abnormality as the cause of chest pain as well as abnormalities of the liver
b. Complete blood count. Used to detect infection and inflammatory disorders
c. Creatine kinase-MB and troponin. High positive predictive value for an AMI if elevated, but may be negative initially
d. D-dimer. Sensitive but not specific for a pulmonary embolism
e. Liver function tests, amylase, Helicobacter pylori. Used to determine a gastrointestinal etiology of the pain, such as liver distention, pancreatitis, and gastric or duodenal ulcers due to H. pylori
f. Toxicology screen. Recommended if cocaine use is believed to be the cause of the chest pain
4. Imaging studies
a. Chest x-ray. Useful in diagnosing pneumonia, pneumothorax, aortic dissection, acute pericarditis, and esophageal rupture
b. Ultrasound. Helpful to diagnose pericardial, valvular disease and to demonstrate cardiac wall motion abnormalities
c. Stress echocardiogram. Used for stable patients who have been ruled out for infarction to determine if cardiac disease is present
d. Computed tomography. Used to diagnose aortic dissection in stable patients and may identify pulmonary embolism or cardiac effusion
IV. DIAGNOSIS
A. Differential diagnosis. The differential diagnosis for atypical chest pain includes (4)
1. Breast lesions. Abscess, carcinoma, fibroadenosis, mastitis
2. Cardiovascular. AMI, angina pectoris, aortic dissection, aortic valvular disease, hypertrophic cardiomyopathy, mitral valve prolapse, myocarditis, pericarditis, primary pulmonary hypertension, thoracic aortic aneurysm, neoplasm
3. Gastrointestinal disease. Esophageal rupture, esophagitis, foreign body presence, gastric distention, gastritis, liver distention, Mallory-Weiss syndrome, pancreatitis, peptic ulcer disease, Plummer-Vinson syndrome, splenic infarct, subphrenic abscess, Zenker’s diverticulum
4. Musculoskeletal disorder. Bruised or fractured rib, cervical disc herniation, costochondritis, intercostal muscle cramp, intercostal myositis, pectoral strain, osteoarthritis, thoracic outlet syndrome
5. Neuralgia. Herpes zoster, neurofibroma, neoplasm, tabes dorsalis, sensitization of dorsal horn spinal neurons in the territory of the intercostobrachial nerve (5)
6. Psychogenic causes. Anxiety, panic attack
7. Pulmonary disease. Bronchitis, neoplasm, pleuritis, pneumonia, pulmonary hypertension, pulmonary embolism
8. Thyroid. Thyroiditis
B. Clinical approach. Once a cardiac etiology for atypical chest pain has been eliminated, a careful history and physical examination usually yield a diagnosis. The aforementioned tests are useful in making the diagnosis and determining an appropriate treatment plan
Thomas J. Hansen
I. BACKGROUND. “Typical” chest pain is pain that is typical of anginal pain. This pain is usually described as substernal, radiating to the left neck and arm, and is pressure like or has a squeezing sensation. “Atypical” chest pain is defined as the absence of this typical presentation.
II. PATHOPHYSIOLOGY. Atypical chest pain can originate in any of the thoracic organs, as well as from extrathoracic sources (e.g., thyroiditis or panic disorder).
III. EVALUATION. The approach to the evaluation of acute chest pain, whether typical or atypical, should be to rapidly assess whether the pain is due to cardiac disease. Atypical chest pain does not rule out an acute myocardial infarction (AMI), especially in women
(1), patients with diabetes, and the elderly, in whom an AMI may present in an atypical fashion. A clinical history of the chest pain and an electrocardiogram (ECG) should be obtained within 5 minutes after presentation
(2). The ECG is critical for guiding initial therapy and decisions regarding diagnosis and treatment.
A. History.
The clinical history should focus on the time of onset, the characteristic of the pain, the location (retrosubsternal, subxiphoid, diffuse), the frequency of the pain (constant, intermittent, acute onset), the duration of the pain, precipitating factors (exertion, stress, food, respiration, movement), the quality of the pain (burning, squeezing, dull, sharp, tearing, heavy), and any associated symptoms (shortness of breath, diaphoresis, nausea, vomiting, jaw pain, back pain, radiation, palpitations, weakness, fatigue).
Other pertinent questions include assessing risk factors for coronary artery disease (diabetes, smoking, hypertension, hypercholesteremia, family history), anorexia, anxiety, cough and/or wheezing, drug use, fever, previous history of deep vein thrombosis or pulmonary embolism, pain increased with recumbency or relieved by leaning forward, presence of a mass, lesion, or rash on the chest, previous history of cancer, pregnancy/postpartum, oral contraceptive use, or trauma, relationship of pain with eating, and syncopal or near-syncopal episodes.
B. Physical examination.
The physical examination should include a rapid assessment of vital signs, as well as oxygen saturation and electrocardiographic evaluation. Following this, an examination of the chest should be performed. Cardiac examination should focus on pericardial rubs, systolic and diastolic murmurs, third or fourth heart sounds, and distended jugular veins. Auscultation of the lungs should focus on diminished breath sounds, a pleural rub, rales, rhonchi, and wheezes. Examination of the legs should focus on edema and poor perfusion of a limb, which may indicate an aortic dissection. Examination of the musculoskeletal system should focus on reproducible or localized pain. Examination of the skin should assess for lesions, masses, or rashes.
C. Testing
1. Oxygen saturation. Oxygen saturation below 92% may indicate a myocardial infarction, spontaneous pneumothorax, pulmonary embolism, or pneumonia. An arterial blood gas is warranted.
2. ECG. Always compare with an old ECG when available. The presence of T wave inversion is consistent with myocardial ischemia. ST elevation is consistent with myocardial injury, and ST depression is consistent with subendocardial infarction. A Q wave is diagnostic of a myocardial infarction (3). A pulmonary embolism is classically associated with the S1Q3T3 pattern, representing a large S wave in I, an ST depression in II, and a large Q wave in III with T wave inversion. Sensitivity of this is less than 20%, however. Acute pericarditis demonstrates diffuse ST-segment elevation, in which the ST segment is flat or slightly concave, and PR depression.
3. Other laboratory tests
a. Comprehensive metabolic profile. Used to detect metabolic abnormality as the cause of chest pain as well as abnormalities of the liver
b. Complete blood count. Used to detect infection and inflammatory disorders
c. Creatine kinase-MB and troponin. High positive predictive value for an AMI if elevated, but may be negative initially
d. D-dimer. Sensitive but not specific for a pulmonary embolism
e. Liver function tests, amylase, Helicobacter pylori. Used to determine a gastrointestinal etiology of the pain, such as liver distention, pancreatitis, and gastric or duodenal ulcers due to H. pylori
f. Toxicology screen. Recommended if cocaine use is believed to be the cause of the chest pain
4. Imaging studies
a. Chest x-ray. Useful in diagnosing pneumonia, pneumothorax, aortic dissection, acute pericarditis, and esophageal rupture
b. Ultrasound. Helpful to diagnose pericardial, valvular disease and to demonstrate cardiac wall motion abnormalities
c. Stress echocardiogram. Used for stable patients who have been ruled out for infarction to determine if cardiac disease is present
d. Computed tomography. Used to diagnose aortic dissection in stable patients and may identify pulmonary embolism or cardiac effusion
IV. DIAGNOSIS
A. Differential diagnosis. The differential diagnosis for atypical chest pain includes (4)
1. Breast lesions. Abscess, carcinoma, fibroadenosis, mastitis
2. Cardiovascular. AMI, angina pectoris, aortic dissection, aortic valvular disease, hypertrophic cardiomyopathy, mitral valve prolapse, myocarditis, pericarditis, primary pulmonary hypertension, thoracic aortic aneurysm, neoplasm
3. Gastrointestinal disease. Esophageal rupture, esophagitis, foreign body presence, gastric distention, gastritis, liver distention, Mallory-Weiss syndrome, pancreatitis, peptic ulcer disease, Plummer-Vinson syndrome, splenic infarct, subphrenic abscess, Zenker’s diverticulum
4. Musculoskeletal disorder. Bruised or fractured rib, cervical disc herniation, costochondritis, intercostal muscle cramp, intercostal myositis, pectoral strain, osteoarthritis, thoracic outlet syndrome
5. Neuralgia. Herpes zoster, neurofibroma, neoplasm, tabes dorsalis, sensitization of dorsal horn spinal neurons in the territory of the intercostobrachial nerve (5)
6. Psychogenic causes. Anxiety, panic attack
7. Pulmonary disease. Bronchitis, neoplasm, pleuritis, pneumonia, pulmonary hypertension, pulmonary embolism
8. Thyroid. Thyroiditis
B. Clinical approach. Once a cardiac etiology for atypical chest pain has been eliminated, a careful history and physical examination usually yield a diagnosis. The aforementioned tests are useful in making the diagnosis and determining an appropriate treatment plan
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