What non‑cardiac, non‑reflux causes could explain chest pain or discomfort after ruling out heart disease and proton‑pump inhibitor‑responsive heartburn?

Non-Cardiac, Non-Reflux Causes of Chest Pain

After excluding cardiac disease and GERD/PPI-responsive heartburn, musculoskeletal causes are the most common explanation for chest pain, followed by esophageal motility disorders, psychological conditions, and less commonly respiratory causes. 1

Systematic Approach to Differential Diagnosis

Most Common: Musculoskeletal Causes

The 2021 AHA/ACC/CHEST Guidelines explicitly state that musculoskeletal causes are the most common non-cardiac source of chest pain 1. These include:

• Costochondritis – inflammation of costochondral joints
• Muscle strain – from overuse or minor trauma
• Rib fracture – may be occult or from recent chest trauma

Key diagnostic feature: Chest wall tenderness on palpation or pain that worsens with inspiration markedly reduces the probability of cardiac causes and points toward musculoskeletal origin 1.

Gastrointestinal Causes Beyond Simple Reflux

Since you've ruled out PPI-responsive heartburn, consider these non-reflux esophageal disorders:

Esophageal Motility Disorders

These present with squeezing retrosternal pain or spasm, often with dysphagia 1:

• Achalasia
• Distal esophageal spasm
• Nutcracker esophagus (hypercontractile esophagus)

Diagnostic pathway: If upper endoscopy is normal and symptoms persist despite acid suppression trial, proceed to esophageal function testing (high-resolution manometry) and pH monitoring 1.

Non-Reflux Esophagitis

• Medication-induced esophagitis – specifically ask about NSAIDs, potassium supplements, iron, or bisphosphonates 1
• Infectious esophagitis – candidiasis in immunocompromised patients
• Eosinophilic esophagitis – consider in patients with dysphagia, food impaction, or atopic history 2
• Radiation-induced esophagitis

Other GI Causes

• Peptic ulcer disease – from medications or H. pylori
• Gastritis – particularly medication-induced

Red flags requiring urgent evaluation (within 2 weeks): dysphagia, odynophagia, GI bleeding, unexplained iron deficiency anemia, weight loss, recurrent vomiting 1.

Respiratory Causes

While less frequent, these are potentially life-threatening and must be excluded 1:

• Pulmonary embolism – often accompanied by dyspnea, tachycardia
• Pneumonia – localized pleuritic pain with friction rub
• Pneumothorax – pleuritic pain with unilateral absent breath sounds

Clinical clue: Many patients will have dyspnea in addition to chest pain 1.

Psychological Causes

These are diagnoses of exclusion but merit serious consideration 1. The 2021 guidelines give a Class 2a recommendation for cognitive-behavioral therapy referral in patients with recurrent presentations and negative workup 1.

Common psychological contributors include:

• Panic disorder
• Anxiety disorders
• Major depression

Important caveat: Epidemiologic studies show high prevalence of these conditions in non-cardiac chest pain patients 3, 4. However, detection of one condition (e.g., anxiety) does not exclude another organic cause.

Less Common Considerations

• Herpes zoster – painful rash in dermatomal distribution (may precede rash)
• Esophageal rupture – severe pain with tympanic abdomen (life-threatening)

Recommended Diagnostic Algorithm

1. Careful history focusing on:

   • Medication use (NSAIDs, bisphosphonates, potassium, iron)
   • Chest wall tenderness or pain with palpation/inspiration
   • Associated dysphagia, odynophagia, or food impaction
   • Atopic history (asthma, allergies)
   • Psychological stressors

2. Physical examination:

   • Palpate costochondral joints for tenderness
   • Assess for chest wall tenderness
   • Listen for friction rubs, absent breath sounds
   • Check for dermatomal rash

3. If esophageal symptoms present:

   • Consider upper endoscopy (especially with red flags)
   • If endoscopy normal and symptoms persist: esophageal manometry and pH monitoring

4. If musculoskeletal features predominate:

   • Trial of NSAIDs (if not contraindicated)
   • Physical therapy referral

5. If recurrent presentations with negative workup:

   • Consider cognitive-behavioral therapy referral 1
   • Evaluate for neuromodulator therapy (venlafaxine, sertraline, imipramine) 3

Critical Pitfalls to Avoid

• Don't assume one diagnosis excludes another – patients can have multiple concurrent causes of chest pain
• Don't overlook medication-induced esophagitis – specifically inquire about common culprits
• Don't dismiss psychological causes – they are common and treatable, not "all in the patient's head"
• Don't forget that absence of heartburn doesn't exclude esophageal pathology – motility disorders and non-reflux esophagitis don't present with typical reflux symptoms