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Chest pain is a very common complaint. Many patients are well aware that it is a warning of potential life-threatening disorders and seek evaluation for minimal symptoms. Other patients, including many with serious disease, minimize or ignore its warnings. Pain perception (both character and severity) varies greatly between individuals as well as between men and women. However described, chest pain should never be dismissed without an explanation of its cause.

Pathophysiology

The heart, lungs, esophagus, and great vessels provide afferent visceral input through the same thoracic autonomic ganglia. A painful stimulus in these organs is typically perceived as originating in the chest, but because afferent nerve fibers overlap in the dorsal ganglia, thoracic pain may be felt (as referred pain) anywhere between the umbilicus and the ear, including the upper extremities.

Painful stimuli from thoracic organs can produce discomfort described as pressure, tearing, gas with the urge to eructate, indigestion, burning, aching, stabbing, and sometimes sharp needle-like pain. When the sensation is visceral in origin, many patients deny they are having pain and insist it is merely “discomfort.”

Etiology

Many disorders produce chest pain or discomfort. These disorders may involve the cardiovascular, GI, pulmonary, neurologic, or musculoskeletal systems (see Table 6: Approach to the Cardiac Patient: Some Causes of Chest Pain).

Some disorders are immediately life threatening:

• Acute coronary syndromes (acute MI/unstable angina)
• Thoracic aortic dissection
• Tension pneumothorax
• Esophageal rupture
• Pulmonary embolism (PE)

Other causes range from serious, potential threats to life to causes that are simply uncomfortable. Often no cause can be confirmed even after full evaluation.

Overall, the most common causes are

• Chest wall disorders (ie, those involving muscle, rib, or cartilage)
• Pleural disorders
• GI disorders (eg, esophageal reflux or spasm, ulcer disease, cholelithiasis)
• Idiopathic
• Acute coronary syndromes

Table 6
Some Causes of Chest Pain Cause Suggestive Findings Diagnostic Approach* Cardiovascular Myocardial ischemia (acute MI/unstable angina/angina) Acute, crushing pain radiating to the jaw or arm Exertional pain relieved by rest (angina pectoris) S4 gallop Sometimes late systolic murmur Often red flag findings† Serial ECGs and cardiac markers; admit or observe Stress imaging test considered in patients with negative ECG findings and no cardiac marker elevation Often heart catheterization and coronary angiography if findings are positive 1Thoracic aortic dissection Sudden, tearing pain radiating to the back Some patients have syncope, stroke, or leg ischemia Pulse or BP may be unequal in extremities Age > 55 Hypertension Red flag findings† Chest x-ray with findings suggesting diagnosis Enhanced CT scan of aorta for confirmation Transthoracic or transesophageal echocardiography 2Pericarditis Constant or intermittent sharp pain often aggravated by breathing, swallowing food, or supine position and relieved by sitting leaning forward Pericardial friction rub Jugular venous distention ECG usually diagnostic Serum cardiac markers (showing elevated troponin with normal CPK level) 2Myocarditis Fever, dyspnea, fatigue, chest pain, recent viral or other infection Sometimes findings of heart failure, pericarditis, or both ECG Serum cardiac markers ESR C-reactive protein Usually echocardiography GI 1Esophageal rupture Sudden, severe pain following vomiting or instrumentation (eg, esophagogastroscopy or transesophageal echocardiography) Subcutaneous crepitus on auscultation Multiple red flag findings† Chest x-ray findings suggest diagnosis Esophagography with water-soluble contrast for confirmation 2Pancreatitis Pain in the epigastrium or lower chest that is often worse when lying flat and is relieved by leaning forward Vomiting Upper abdominal tenderness Shock Often history of alcohol abuse or biliary tract disease Serum amylase and lipase Sometimes abdominal CT 3Peptic ulcer Recurrent, vague epigastric or right upper quadrant discomfort in a patient who smokes or uses alcohol excessively that is relieved by food, antacids, or both No red flag findings† Clinical evaluation Sometimes endoscopy Sometimes testing for Helicobacter pylori 3Esophageal reflux (GERD) Recurrent burning pain radiating from epigastrium to throat that is exacerbated by bending down or lying down and relieved by antacids Clinical evaluation Sometimes endoscopy Sometimes motility studies 3Biliary tract disease Recurrent right upper quadrant or epigastric discomfort following meals (but not exertion) Ultrasonography of gallbladder 3Esophageal motility disorders Pain, insidious onset, long-standing, may or may not accompany swallowing Usually also swallowing difficulty Barium swallow Pulmonary 1Pulmonary embolism Often pleuritic pain, dyspnea, tachycardia Sometimes mild fever, hemoptysis, shock More likely with risk factors present (see Table 7: Approach to the Cardiac Patient: Clinical Prediction Rule for Diagnosing Pulmonary Embolism) Varies with clinical suspicion (see Fig. 3: Approach to the Cardiac Patient: PE testing algorithm) 1Tension pneumothorax Significant dyspnea, hypotension, neck vein distention, unilateral diminished breath sounds and hyperresonance to percussion Sometimes subcutaneous air Usually clinical Obvious on chest x-ray 2Pneumonia Fever, chills, cough, and purulent sputum Often dyspnea, tachycardia, signs of consolidation on examination Chest x-ray 2Pneumothorax Sometimes, unilateral diminished breath sounds, subcutaneous air Chest x-ray Pleuritis May have preceding pneumonia, pulmonary embolism, or viral respiratory infection Pain with breathing, cough Examination unremarkable Usually clinical evaluation Other 3Musculoskeletal chest wall pain (including trauma, overuse, costochondritis) Often suggested by history Pain typically persistent (typically days or longer), worsened with passive and active motion Diffuse or focal tenderness Clinical evaluation 2Various thoracic cancers Variable sometimes chronic cough, smoking history, signs of chronic illness (weight loss, fever), cervical lymphadenopathy Chest x-ray Chest CT if x-ray findings suggestive Bone scan considered for persistent, focal rib pain 3Herpes zoster infection Sharp, band-like pain mid-thorax unilaterally Classic linear, vesicular rash Pain may precede rash by several days Clinical evaluation 3Idiopathic Various features No red flag findings Diagnosis of exclusion *Most patients with chest pain should have pulse oximetry, ECG, and chest x-ray (basic tests). If there is suspicion of coronary ischemia, serum cardiac markers (troponin, CPK) should also be checked. †Red flag findings include abnormal vital signs (tachycardia, bradycardia, tachypnea, hypotension), signs of hypoperfusion (eg, confusion, ashen color, diaphoresis), shortness of breath, asymmetric breath sounds or pulses, new heart murmurs, or pulsus paradoxus > 10 mm Hg. S4 = 4th heart sound. 1Immediate life threats. 2Potential life threats. 3Uncomfortable but usually not dangerous.

Evaluation

History: History of present illness should note the location, duration, character, and quality of the pain. The patient should be asked about any precipitating events (eg, straining or overuse of chest muscles), as well as any triggering and relieving factors. Specific factors to note include whether pain is present during exertion or at rest, presence of psychologic stress, whether pain occurs during respiration or coughing, difficulty swallowing, relationship to meals, and positions that relieve or exacerbate pain (eg, lying flat, leaning forward). Previous similar episodes and their circumstances should be noted with attention to the similarity or lack thereof. Important associated symptoms to seek include dyspnea, palpitations, syncope, diaphoresis, nausea or vomiting, cough, fever, and chills.

Review of systems should seek symptoms of possible causes, including leg pain, swelling, or both (deep venous thrombosis [DVT] and therefore possible PE) and chronic weakness, malaise, and weight loss (cancer).

Past medical history should document known causes, particularly cardiovascular and GI disorders, and any cardiac investigations or procedures (eg, stress testing, catheterization). Risk factors for coronary artery disease (CAD—eg, hypertension, hyperlipidemia, diabetes, cerebrovascular disease, tobacco use) or PE (eg, lower extremity injury, recent surgery, immobilization, known cancer, pregnancy) should also be noted.

Drug history should note use of drugs that can trigger coronary artery spasm (eg, cocaine, triptans, phosphodiesterase inhibitors) or GI disease (particularly alcohol, NSAIDs).

Family history should note history of MI (particularly at an early age) and hyperlipidemia.

Physical examination: Vital signs and weight are measured, and body mass index (BMI) is calculated. Pulses are palpated in both arms and both legs, BP is measured in both arms, and pulsus paradoxus is measured.

General appearance is noted (eg, pallor, diaphoresis, cyanosis, anxiety).

Neck is inspected for venous distention and hepatojugular reflux, and the venous wave forms are noted. The neck is palpated for carotid pulses, lymphadenopathy, or thyroid abnormality. The carotid arteries are auscultated for bruit.

Lungs are percussed and auscultated for presence and symmetry of breath sounds, signs of congestion (dry or wet rales, rhonchi), consolidation (pectorilloquy), pleural friction rubs, and effusion (decreased breath sounds, dullness to percussion).

The cardiac examination notes the intensity and timing of the 1st heart sound (S₁) and 2nd heart sound (S₂), the respiratory movement of the pulmonic component of S₂, clicks and snap of the mitral apparatus, pericardial friction rubs, murmurs, and gallops. When murmurs are detected, the timing, duration, pitch, shape, and intensity and the response to changes of position, handgrip, and the Valsalva maneuver should be noted. When gallops are detected, differentiation should be made between the 4th heart sound (S₄), which is often present with diastolic dysfunction or myocardial ischemia, and the 3rd heart sound (S₃), which is present with systolic dysfunction.

The chest is inspected for skin lesions of trauma or herpes zoster infection and palpated for crepitance (suggesting subcutaneous air) and tenderness. The abdomen is palpated for tenderness, organomegaly, and masses or tenderness, particularly in the epigastric and right upper quadrant regions.

The legs are examined for arterial pulses, adequacy of perfusion, edema, varicose veins, and signs of DVT (eg, swelling, erythema, and tenderness).

Red flags: Certain findings raise suspicion of a more serious etiology of chest pain:

• Abnormal vital signs (tachycardia, bradycardia, tachypnea, hypotension)
• Signs of hypoperfusion (eg, confusion, ashen color, diaphoresis)
• Shortness of breath
• Asymmetric breath sounds or pulses
• New heart murmurs
• Pulsus paradoxus > 10 mm Hg

Interpretation of findings: Symptoms and signs of thoracic disorders vary greatly, and those of serious and nonserious conditions often overlap. Although red flag findings indicate a high likelihood of serious disease, and many disorders have “classic” manifestations (see Table 6: Approach to the Cardiac Patient: Some Causes of Chest Pain), many patients who have serious illness do not present with these classic symptoms and signs. For example, patients with myocardial ischemia may complain only of indigestion or have a very tender chest wall on palpation. A high index of suspicion is important when evaluating patients with chest pain. Nonetheless, some distinctions and generalizations are possible.

Duration of pain can provide clues to the severity of the disorder. Long-standing pain (ie, for weeks or months) is not a manifestation of a disorder that is immediately life threatening. Such pain is often musculoskeletal in origin, although GI origin or a cancer should be considered, particularly in patients who are elderly. Similarly, brief (< 5 sec), sharp, intermittent pains rarely result from serious disorders. Serious disorders typically manifest pain lasting minutes to hours, although episodes may be recurrent (eg, unstable angina may cause several bouts of pain over 1 or more days).

Patient age is helpful in evaluating chest pain. Chest pain in children and young adults (< 30 yr) is less likely to result from myocardial ischemia, although MI can occur in people in their 20s. Musculoskeletal and pulmonary disorders are more common causes in these age groups.

Exacerbation and relief of symptoms also is helpful in evaluating chest pain. Although angina can be felt anywhere between the ear and the umbilicus (and often not in the chest), it is typically consistently related to physical or emotional stress, ie, patients do not experience angina from climbing one flight of stairs one day and tolerate 3 flights the next day. Nocturnal angina is characteristic of heart failure or coronary artery spasm.

Pain from many disorders, both serious and minor, can be exacerbated by respiration, movement, or palpation of the chest. These findings are not specific for origin in the chest wall; about 15% of patients with acute MI have chest tenderness on palpation.

Nitroglycerin Some Trade Names
NITRO-BID
NITRO-DUR
NITROL
NITROQUICK
Click for Drug Monograph
may relieve pain of both myocardial ischemia and noncardiac smooth muscle spasm (eg, esophageal or biliary disorders); its efficacy or lack thereof should not be used for diagnosis.

Associated findings may also suggest a cause. Fever is nonspecific but, if accompanied by cough, suggests a pulmonary cause. Patients with Raynaud's syndrome or migraine headaches sometimes have coronary spasm.

The presence or absence of risk factors for CAD (eg, hypertension, hypercholesterolemia, smoking, obesity, diabetes, positive family history) alters the probability of underlying CAD but does not help diagnose the cause of a given episode of acute chest pain. Patients with those factors may well have another cause of chest pain, and patients without them may have an acute coronary syndrome. However, known CAD in a patient with chest pain raises the likelihood of that diagnosis as the cause (particularly if the patient describes the symptoms as “like my angina” or “like my last heart attack”).

Testing: For adults with acute chest pain, immediate life threats must be ruled out. Most patients should initially have pulse oximetry, ECG, and chest x-ray. If symptoms suggest an acute coronary syndrome or if no other cause is clear (particularly in at-risk patients), troponin and CPK levels are measured. If a PE is considered possible, D-dimer testing is done. Expeditious evaluation is essential because if MI or other acute coronary syndrome is present, the patient should be sent immediately to the heart catheterization laboratory (when available); the therapeutic window for primary percutaneous coronary intervention is 90 min and that for thrombolysis is only slightly longer.

Some abnormal findings on these tests confirm a diagnosis (eg, acute MI, pneumothorax, pneumonia). Other abnormalities suggest a diagnosis or at least the need to pursue further investigation (eg, abnormal aortic contour suggests need for testing for thoracic aortic dissection). Thus, if these initial test results are normal, thoracic aortic dissection, tension pneumothorax, and esophageal rupture are highly unlikely. However, in acute coronary syndromes, ECG may not change for several hours or sometimes not at all, and in PE, oxygenation may be normal. Thus, other studies may need to be obtained based on findings from the history and physical examination (see Table 6: Approach to the Cardiac Patient: Some Causes of Chest Pain).

Because a single normal set of cardiac markers does not rule out a cardiac cause, patients whose symptoms suggest an acute coronary syndrome should have serial measurement of cardiac markers (troponin and CPK-MB fraction) and ECGs. Some clinicians follow these tests (acutely or within several days) with a stress ECG or a stress imaging test. Drug treatment is begun while awaiting results from the 2nd set of markers unless there is a clear contraindication. A diagnostic trial of sublingual nitroglycerin Some Trade Names
NITRO-BID
NITRO-DUR
NITROL
NITROQUICK
Click for Drug Monograph
or an oral liquid antacid does not adequately differentiate myocardial ischemia from gastroesophageal reflux disease or gastritis. Either drug may relieve symptoms of either disorder. Troponin will be elevated in all acute coronary syndromes except new-onset angina and often in other disorders that damage the myocardium (eg, myocarditis, pericarditis, aortic dissection involving coronary artery flow, PE, heart failure, severe sepsis). CPK may be elevated from damage to any muscle tissue, but CPK-MB elevation is specific to damage to the myocardium. ST-segment abnormality on the ECG may be nonspecific or due to antecedent disorders, so comparison with previous ECGs is important.

The likelihood of PE is affected by a number of factors (see Table 7: Approach to the Cardiac Patient: Clinical Prediction Rule for Diagnosing Pulmonary Embolism), which can be used in an algorithm (see Fig. 3: Approach to the Cardiac Patient: PE testing algorithm) to derive an approach to testing.

In patients with chronic chest pain, immediate threats to life are unlikely. Most clinicians initially obtain a chest x-ray and do other tests based on symptoms and signs.

Fig. 3
PE testing algorithm Use pretest probability to determine testing

Table 7
Clinical Prediction Rule for Diagnosing Pulmonary Embolism I. Establish clinical probability — add points to determine total score and thus probability Clinical Risk Points Clinical signs and symptoms of DVT (objective leg swelling, pain with palpation) 3 PE as or more likely than alternative diagnosis 3 Heart rate > 100 beats/min 1.5 Immobilization ≥ 3 days 1.5 Surgery in previous 4 wk 1.5 Previous DVT or PE 1.5 Hemoptysis 1 Malignancy (including in those stopping cancer treatment within 6 mo) 1 Total Score Probability > 6 High 2–6 Moderate < 2 Low II. Use pretest probability to determine testing DVT = Deep venous thrombosis; PE = pulmonary embolism; V/Q = ventilation/perfusion.

Treatment

Specific identified disorders are treated. If etiology is not clearly benign, patients are usually admitted to the hospital or an observation unit for cardiac monitoring and more extensive evaluation. Symptoms are treated with acetaminophen Some Trade Names
GENAPAP
TYLENOL
VALORIN
Click for Drug Monograph
or opioids as needed (see Pain: Introduction), pending a diagnosis. Pain relief following opioid treatment should not diminish the urgency of ruling out serious and life-threatening disease.

Geriatrics Essentials

The probability of serious and life-threatening disease increases with age. Many elderly patients recover more slowly than younger patients but survive for significant time if properly diagnosed and treated. Drug doses are usually lower, and rapidity of dose escalation is slower. Chronic disorders (eg, decreased renal function) are often present and may complicate diagnosis and treatment.

Key Points

• Immediate life threats must be ruled out first.
• Some serious disorders, particularly coronary ischemia and PE, often do not have a classic presentation.
• Most patients should have pulse oximetry, ECG, cardiac markers, and chest x-ray.
• Evaluation must be prompt so that patients with ST-elevation MI can be in the heart catheterization laboratory (or have thrombolysis) within the 90-min standard.
• If PE is highly likely, treat with antithrombin drugs while proving the diagnosis; another embolus in a patient who is not receiving anticoagulants may be fatal.

Last full review/revision April 2009 by Paul H. Tanser, MD

Content last modified April 2009