Chest Pain: Clinical Overview

Life-Threatening Causes to Rule Out First ("The Big Six")

Full Differential by System

Cardiac

• ACS (STEMI, NSTEMI, unstable angina)
• Stable angina — exertional, relieved by rest; 2–10 min duration
• Pericarditis — sharp, pleuritic; relieved by sitting forward; friction rub; diffuse ST elevation on ECG
• Myocarditis — younger patients, post-viral
• Aortic stenosis — anginal episodes with severe stenosis
• Hypertrophic cardiomyopathy (HCM) — exertional chest pain from subendocardial ischemia
• Prinzmetal (vasospastic) angina — coronary vasospasm, rest pain, ST elevation
• Cocaine use — coronary vasospasm ± thrombosis

Vascular

• Aortic dissection — ascending (chest → back), descending (back → abdomen); check peripheral pulses; confirm with CTA/TEE/MRI

Pulmonary

• PE — pleuritic pain, dyspnea; most thromboemboli are actually NOT associated with chest pain
• Pneumothorax — pleuritic, sudden onset; spontaneous (tall young males) or traumatic
• Pleuritis/pleurisy — localized, unilateral, sharp pain worsened by deep breathing; referred to ipsilateral shoulder if diaphragmatic
• Pneumonia — bacterial pneumonia may produce pleuritic chest pain
• Pulmonary hypertension — exertional chest discomfort with severe dyspnea, cyanosis
• Herpes zoster — dermatomal pain; rash may appear 1–2 days later

Gastrointestinal

• GERD / esophageal reflux — may mimic angina; can respond to nitroglycerin
• Esophageal spasm — chest pain responsive to nitrates (may fool clinician)
• Peptic ulcer disease
• Biliary colic / cholecystitis

Musculoskeletal

• Costochondritis / Tietze syndrome — point tenderness over costochondral junctions; reproducible on palpation
• Chest wall trauma, rib fractures — focal tenderness
• Cervical radiculopathy — dermatomal radiation
• Intercostal neuritis — lancinating pain unrelated to breathing movements

Other

• Severe anemia — O₂ supply-demand mismatch causing angina-like pain
• Thyrotoxicosis — increased myocardial demand
• Anxiety / panic disorder
• Precordial catch syndrome (Texidor's twinge) — pediatric; sharp, left-sided, self-limited within minutes; benign

Key History Features

Important caveat: 22% of patients with AMI described their pain as sharp or stabbing. Nonclassic ACS presentations are common — especially in women, elderly, diabetics, and racial minorities. Never exclude ACS based on atypical pain quality alone.

Initial Evaluation

1. ECG within 10 minutes — look for ST changes, LBBB, right heart strain pattern (PE)
2. Vital signs — BP in both arms (dissection), O₂ saturation, heart rate
3. Chest X-ray — widened mediastinum (dissection), pneumothorax, infiltrate, effusion
4. Labs — troponin (serial), BNP/NT-proBNP, D-dimer, CBC, BMP
5. History — onset, character, radiation, severity, duration, exacerbating/alleviating factors, associated symptoms (diaphoresis, dyspnea, nausea, palpitations, syncope)
6. Physical exam — pulse symmetry, auscultation (rub, murmur, absent breath sounds), chest wall tenderness

Special Populations

• Women: more likely to present with atypical symptoms; greater diagnostic and treatment delays
• Elderly: may have painless ("silent") MI; diaphoresis or dyspnea may be the predominant complaint
• Diabetics: autonomic neuropathy reduces pain perception — higher rate of silent ischemia
• Pediatric: most common causes are musculoskeletal, asthma, GERD — exertional chest pain with family history of sudden death requires cardiac workup