What is the differential diagnosis for nocturnal chest pain that is more pronounced on the left side?

Differential Diagnosis for Nocturnal Left-Sided Chest Pain

Nocturnal chest pain with left-sided predominance requires immediate consideration of gastroesophageal reflux disease (GERD)/esophagitis and pericarditis as primary diagnoses, while acute coronary syndrome must be ruled out despite the atypical nocturnal-only pattern. 1

Life-Threatening Causes to Exclude First

Cardiac causes must be evaluated urgently despite the nocturnal pattern:

• Acute Coronary Syndrome (ACS) can occur at rest without exertion, particularly in unstable angina or NSTEMI, presenting with retrosternal pressure building over minutes, radiating to the left arm/jaw/neck, with associated diaphoresis, dyspnea, or nausea 1, 2

  • The examination may be completely normal in uncomplicated cases, so absence of findings does not exclude ACS 1, 2
  • Women, elderly patients, and those with diabetes may present with atypical symptoms including left-sided or sharp pain 1

• Pericarditis is a critical consideration given the nocturnal pattern, as it characteristically presents with sharp, pleuritic chest pain that worsens when lying supine and improves when leaning forward, potentially with a friction rub on examination 1, 3

• Aortic dissection presents with sudden-onset "ripping" or "tearing" chest pain radiating to the back, with pulse differentials between extremities—though less likely given the recurrent nocturnal pattern 1, 2

Most Likely Diagnoses for Nocturnal Left-Sided Pain

Gastroesophageal causes are the leading consideration:

• GERD/Esophagitis presents with burning retrosternal pain that is positionally related (worse when supine at night), may radiate to the left chest, and is typically relieved by antacids 3, 2

  • This is the most common benign cause that worsens at night due to recumbent positioning 3

• Esophageal spasm can mimic cardiac pain and may respond to nitroglycerin, making it a critical pitfall—nitroglycerin response should NOT be used as a diagnostic criterion for cardiac ischemia 1, 3, 2

Musculoskeletal causes:

• Costochondritis/chest wall pain is characterized by tenderness of costochondral joints on palpation, pain reproducible with chest wall pressure, and pain affected by position, breathing, or turning 1, 3, 2
  • Pain localized to a very limited area is unlikely to be cardiac 1

Critical Historical Features to Distinguish Causes

Features suggesting cardiac origin (requiring urgent evaluation):

• Gradual onset over minutes with pressure/heaviness/squeezing quality 1
• Radiation to left arm, neck, or jaw 1, 3
• Associated diaphoresis, dyspnea, nausea, or syncope 1

Features suggesting non-cardiac origin:

• Sharp pain that increases with inspiration and lying supine (suggests pericarditis) 1
• Fleeting pain lasting only seconds (unlikely ischemic) 1
• Pain reproducible with palpation or position changes (suggests musculoskeletal) 1, 3
• Burning quality related to meals or relieved by antacids (suggests GERD) 3

Immediate Diagnostic Approach

Mandatory initial workup:

• ECG should be obtained immediately to evaluate for ST-segment changes, new left bundle branch block, Q waves, or T-wave inversions 1, 2
• Focused cardiovascular examination to assess for murmurs, friction rub, pulse differentials, or signs of heart failure 1, 2
• Cardiac troponin measurement if any suspicion of ACS exists 1, 2

Common Pitfalls to Avoid

• Do not use nitroglycerin response as a diagnostic test—esophageal spasm and other conditions also respond to nitroglycerin 1, 3, 2
• Do not dismiss chest pain in women or elderly patients—they frequently present with atypical symptoms including left-sided or sharp pain 1, 3
• Do not assume a normal examination excludes ACS—uncomplicated myocardial infarction may have no physical findings 1, 2
• Positional chest pain is usually non-ischemic but pericarditis (which is positional) remains a serious cardiac cause 1

Risk Stratification for Urgent Referral

Immediate emergency department transfer is required if:

• Age >75 years with accompanying dyspnea, syncope, or acute delirium 3
• Any ECG abnormalities suggestive of ischemia 1, 2
• Clinical evidence of ACS or other life-threatening causes 1
• Patients with diabetes, renal insufficiency, or known cardiovascular disease 3, 4