Chest Pain

History and Physical Examination
Despite major innovations in diagnostic technology and advances in medical therapy, a well-performed history and physical examination remain the cornerstone of good patient care. In addition to providing important clues about a patient’s illness, a thorough evaluation helps to direct further diagnostic testing and therapy. It also provides the physician an opportunity to establish rapport with the patient; strong physician-patient relationships establish trust and help to ensure compliance with treatment regimens. Conversely, an inadequate or poorly obtained history may trigger inappropriate or incomplete testing and contribute to additional morbidity and mortality.

The cardinal symptoms of heart disease include chest pain, dyspnea, and palpitations. These symptoms will be discussed in this and the following sections. A thorough history of each symptom includes information regarding symptom duration, frequency, quality, severity, aggravating or alleviating factors, and associated symptoms. With regard to chest pain, location and radiation are also important features.

Clinical Manifestations

History
Angina is the cardinal symptom of coronary artery disease (CAD) and results from inadequate oxygen delivery to the myocardium. It is usually an uncomfortable sensation rather than a pain, and may he described as:

  • an ache
  • hearthurn
  • indigestion
  • a choking sensation
  • constriction
  • pressure

The symptom is generally substernal in location, but may radiate or localize to the precordium, neck, jaw, shoulders, anns, or epigastrium. Patients with angina often use a clenched fist to indicate the site of discomfort (Levine’s sign). Anginal pain is generally triggered by exertion, relieved by rest, and resolves more rapidly (within 1 to 5 minutes) with sublingual nitroglycerin.

Other precipitating factors include cold weather, walking on inclines, emotional upset, fright, and the postprandial state. Occasionally, it may occur spontaneously in the early morning hours.
Anginal chest pain may occur in several patterns:

  • Stable angina is angina that occurs in a welldefined, reproducible pattern-usually on exertion.
  • Unstable angina refers to angina that is new, occurs at rest, or occurs more frequently than the person’s usual angina.
  • The pain of a myocardial infarction is usually more intense and longer lasting than angina, radiates more widely, and is often accompanied by dyspnea, diaphoresis, palpitations, nausea, and vomiting.

Importantly, many patients, especially diabetics, do not have typical anginal chest pain during an ischemic episode or a myocardial infarction. Rather, they may present with atypical chest pain, restlessness, dyspnea, or diaphoresis.

Physical Examination
Physical findings can be quite helpful in the evaluation of chest pain and may occasionally implicate specific etiologies. A pericardial friction rub is pathognomonic for pericarditis. A late-peaking systolic murmur at the upper sternal border indicates aortic stenosis. Unequal pulses or blood pressure in the arms and the presence of an aortic insufficiency murmur strongly suggest aortic dissection.

Angina may be associated with a normal physical examination; however, an S3), S4, or murmur of mitral regurgitation is often heard during the ischemic episode.

Differential Diagnosis of chest pain

The key to differentiating innocuous causes of chest pain from those that are potentially life threatening lies in the history (see Table 1 -1). The chest pain of aortic stenosis, hypertrophic cardiomyopathy, and pulmonary hypertension may be indistinguishable from angina.

Aortic dissection classically presents with severe substernal chest pain that is tearing in quality, comes on abruptly, and radiates to the interscapular or lumbar region. The sudden onset of chest pain that is associated with dyspnea may berald a Pulmonary embolism; this pain is usually worse upon inspiration (pleuritic) and may be substernal or more lateral in location. A similar pain can occur with pneumonia or a spontaneous pneumothorax. Pericarditis causes chest pain that is substernal or precordial, radiates to the shoulder, is often pleuritic, sharp, worse when swallowing or lying supine, and improved by leaning forward.

Several gastrointestinal disorders (e.g., peptic ulcer disease, gastroesophageal reflux disease, pancreatitis, gall bladder disease) can present with chest pain, but frequently have an abdominal component to the discomfort or are temporally associated with eating, and may be relieved with antacids. Esophageal spasm may mimic angina but it is not related to exertion and is frequently provoked by food. Pain resulting from diseases of the muscles, ligaments, or bones of the chest tends to be localized and is exacerbated by movement or certain postures. Sharp, stabbing chest pains localized to the precordium and lasting only a few seconds are rarely cardiac in etiology and are usually associated with anxiety. Several other historical factors are important to note when evaluating a patient with chest pain. These include:

  • risk factors for CAD (suggests angina)
  • cocaine use (suggests coronary spasm)
  • recent viral illness (suggests pericarditis or pneumonia)
  • recent prolonged immobility (suggests Pulmonary embolism)
  • history of bullous lung disease (suggests pneumothorax)
  • recent injury (suggests musculoskeletal pain)
  • history of Marfan’s syndrome (suggests aortic dissection)

Diagnostic Evaluation

The initial tests for patients with chest pain should include an electrocardiogram (ECC) and a chest x-ray.

The ECC may demonstrate regional ST segment depression/elevation indicating myocardial ischemia/ infarction, or may reveal the diffuse ST segment elevation of pericarditis. A chest x-ray may reveal rib fractures, focal infiltrates of pneumonia, wedge-shaped peripheral infiltrates of pulmonary emboli, or the radiolucency of a pneumothorax. It may also suggest aortic dissection (widened mediastinum), or hiatal hernia (stomach in the thoracic cavity).

If an acute coronary syndrome is suspected, medical therapy should be immediately started and serial ECGs and cardiac enzymes (creatine kinase and troponin) checked to confirm or exclude a myocardial infarction. For patients in whom the diagnosis remains uncertain but CAD is suspected, a stress test can be perfonned for clarification. Chest pain associated with ST segment depression during a stress test is diagnostic of angina. Cardiac catheterization remains the gold standard for the diagnosis of coronary artery disease and may be necessary to rule out significant CAD in a subset of patients for whom other tests are unable to confirm or exclude the diagnosis.

In patients with pulmonary emboli, arterial blood gases usually reveal hypoxia and/or widened A-a gradient, and ventilation/perfusion (V/Q) scanning or spiral CT scanning may confirm the diagnosis. Patients suspected of having an aortic dissection should undergo urgent transesophageal echocardiography, CT scanning with intravenous contrast, or magnetic resonance imaging (MRI). Patients suspected of having a gastroesophageal cause of their chest pain may need a barium swallow (esophageal reflux or rupture), endoscopy (esophagitis, gastritis, peptic ulcer disease), hepatobiliary hydroxyiminodiacetic acid (HIDA) scan or abdominal ultrasound (gall bladder disease), esophageal manometry (esophageal spasm), or continuous esophageal pH measurement (reflux) to confirm the diagnosis.

KEY POINTS
1. The initial evaluation of the patient with chest pain should focus on possible life-threatening causes, including acute cardiac ischemia, aortic dissection, and Pulmonary embolism.
2. Angina classically causes chest pain that is substernal, precipitated by exertion, and relieved with rest or after sublingual nitroglycerin.
3. A variety of pulmonary, musculoskeletal, and gastrointestinal disorders can present with chest pain and may be difficult to distinguish from true angina.

Provided by ArmMed Media
Revision date: July 3, 2011
Last revised: by Andrew G. Epstein, M.D.