Chest Pain

Etiology

It sometimes is helpful to consider the different etiologies of pain. Visceral pain usually presents with a vague distribution pattern meaning that the patient is unlikely to localize the pain to a specific spot. When asking patients to point with one finger where they feel the pain, they will often move their hand around a larger area. Common descriptors of visceral pain are dull, deep, pressure, and squeezing. Visceral pain also refers to other locations as a result of the nerves coursing through somatic nerve fibers as they reach the spinal cord. Ischemic heart pain, for example, may refer to the left or right shoulder, jaw, or left arm. Symptoms like nausea and vomiting may also be a sign of visceral pain. Diaphragmatic irritation may refer to the shoulders as well.[1] Somatic pain is more specific than visceral pain, and patients will usually be able to point to a specific spot. Somatic pain is also less likely to refer to other parts of the body. Common descriptors of somatic pain are sharp, stabbing, and poking.

Epidemiology

In the emergency department, chest pain is the second most common complaint comprising approximately 5% of all emergency department visits. In evaluating for chest pain, the provider should always consider life-threatening causes of chest pain. These are listed below with approximate percent occurrence in patients presenting to the emergency department with chest pain based on a study by Fruerfaard et al. [2]

• Acute coronary syndrome (ACS), 31%
• Pulmonary embolism (PE), 2%
• Pneumothorax (PTX), unreported
• Pericardial tamponade, unreported (pericarditis 4%)
• Aortic dissection, 1%
• Esophageal perforation, unreported

 Other common causes of chest pain with approximate percent occurrence in patients presenting to the emergency department with chest pain include:

• Gastrointestinal reflux disease, 30%
• Musculoskeletal causes, 28%
• Pneumonia/pleuritis, 2%
• Herpes zoster 0.5%
• Pericarditis, unreported

History and Physical

History

Like all workups, chest pain evaluation starts with taking a complete history. Start by getting a good understanding of their complaint.

• Onset: In addition to when the pain started, ask what the patient was doing when the pain started. Was the pain brought on by exertion, or were they at rest?
• Location: Can the patient localize the pain with one finger, or is it diffuse?
• Duration: How long did the pain last?
• Character: Let the patient describe the pain in his or her own words.
• Aggravation/alleviating factors: It is very important to find out what makes the pain worse. Is there an exertional component, is it associated with eating or breathing? Is there a positional component? Don't forget to ask about new workout routines, sports, and lifting. Ask what medications they have tried.
• Radiation: This may clue you into visceral pain.
• Timing: How many times do they experience this pain? For how long does it let up?

Ask about other symptoms, such as:

• Shortness of breath
• Nausea and vomiting
• Fever
• Diaphoresis
• Cough
• Dyspepsia
• Edema
• Calf pain or swelling
• Recent illness

Evaluate for any of the following risk factors:

• ACS risks: prior myocardial infarction(MI), family history of cardiac disease, smoking, hypertension (HTN), hyperlipidemia (HLD), and diabetes
• Pulmonary embolism (PE) risks: prior deep venous thrombosis (DVT) or PE, hormone use (including oral birth control), recent surgery, cancer, or periods of non-ambulation
• Recent gastrointestinal (GI) procedures like scopes
• Drug abuse (cocaine and methamphetamines)

Carefully review the patient’s medical history for cardiac history, coagulopathies, and kidney disease. Ask about family history, especially cardiac, and ask about social histories like drug use and tobacco use.

Once you have thoroughly ruled out life-threatening causes, move on to other possibilities. Pneumonia should be considered in patients with a productive cough and/or recent upper respiratory infection (URI). Gastroesophageal reflux disease (GERD) is a common cause of chest pain so ask about any reflux symptoms. New exercise routines or recent trauma may help support a musculoskeletal cause. [2]

Physical

The physical exam should include:

• Full set of vitals, including blood pressure (BP) measurements in both arms
• General appearance, noting diaphoresis and distress
• Skin exam for the presence of lesions (shingles)
• Neck exam for jugular venous distension (JVD), especially with inspiration (Kussmaul sign)
• Chest, palpate for reproducible pain and crepitus
• Heart exam
• Lung exam
• Abdominal exam
• Extremities for unilateral swelling, calf pain, edema, and symmetric, equal pulses

Evaluation

Many facilities have protocols in place to evaluate for chest pain, but at a minimum, the provider should order the following:

• Electrocardiogram (ECG) preferably in the first 10min of arrival (consider serial ECGs)     
• Chest x-ray
• Complete blood count (CBC), basic metabolic panel (BMP), troponin level (consider serial troponin levels 4hr apart), lipase
• Computed tomography pulmonary angiography (CTPA) if you are considering PE or ventilation-perfusion (VQ) scan if CTPA is contraindicated
• Bedside ultrasound (US) if you are considering pericardial tamponade

Treatment / Management

Acute coronary syndrome (ACS)

A complete discussion of the management of ACS is beyond the scope of this paper; however, initial steps should be performed in patients with a diagnosis of ACS. Place patient on a cardiac monitor, establish intravascular access (IV) access, give 162 mg to 325 mg chewable aspirin, clopidogrel, or ticagrelor (unless bypass surgery is imminent), control pain and consider oxygen (O2) therapy. Nitroglycerin has shown a mortality benefit, aiming for a 10% mean arterial pressure (MAP) reduction in normotensive patients and a 30% MAP reduction in hypertensive patients; avoid in hypotensive patients and those with inferior ST elevation. Patients with ST elevation on ECG patients should receive immediate reperfusion therapy, either pharmacologic (thrombolytics) or transfer to the catheterization laboratory for percutaneous coronary intervention (PCI). PCI is preferred and should be initiated within 90 minutes onsite or 120 minutes if transferred to an outside facility. If PCI is not possible, thrombolytics should be initiated within 30 min. Patients with non-ST elevation myocardial infarction (NSTEMI) and unstable angina should be admitted for a cardiology consult and workup. Patients with stable angina may be appropriate for outpatient workup. In elderly patients and those with comorbidities, patients should be admitted for observation and further cardiac workup. [3][4]

Pulmonary embolism (PE)

CT pulmonary angiogram (CTPA) is the best confirmatory test, a VQ scan can also be used, but this test is not as accurate in patients with chronic lung disease. Patients who are hemodynamically unstable should be started on thrombolytics; stable patients should be started on anticoagulants. [5][6](B2)

Pneumothorax (PTX)

Pneumothorax should be decompressed with a chest tube. [7][8](B3)

Pericardial tamponade

Bedside ultrasound is useful for establishing a diagnosis. A fluid bolus may be used as a temporizing measure. Needle pericardiotomy or pericardial window to relieve pressure inside the pericardial sack.[9]

Aortic dissection

Often immediate surgery is required; consult cardiothoracic surgery early. CT angiography is the best test to evaluate for dissection. Place two large-boar IVs and quickly lower the patient’s blood pressure to systolic between 100 mmHg to 130 mmHg. Start with beta-blocker therapy to prevent reflux tachycardia. [10][11][12]

Esophageal perforation

A left pleural effusion on a chest x-ray may suggest esophageal rupture. A contrast esophagram is the best confirmatory test. This is a medical emergency, and an immediate surgical consult is warranted. [11]

Gastrointestinal reflux disease

The patient can be given viscous lidocaine mixed with Maalox (known as a GI cocktail). While this is therapeutic, it is not diagnostic. ACS can present with dyspepsia and may respond to a GI cocktail; it is, therefore, important to rule out ACS before assigning GERD as a final diagnosis. Long-term treatment of GERD is best accomplished with proton pump inhibitor (PPI) or H2 blocker therapy.[13]

Differential Diagnosis

• Acute coronary syndrome

• Aortic dissection

• Embolism

• Gastroesophageal reflux

• Muscle or skeletal pain

• Esophageal rupture

• Pericarditis

• Pneumonia shingles

• Pneumothorax

• Pulmonary embolism
• Cervical radiculopathy
• Esophageal spasm