What are the likely causes of chest pain that worsens when lying down, and what is the recommended evaluation and management?

Chest Pain Worse with Laying Down

Sharp, pleuritic chest pain that worsens when lying supine and improves when sitting forward is the hallmark of acute pericarditis, but you must immediately exclude acute coronary syndrome, pulmonary embolism, and aortic dissection before confirming this diagnosis. 1, 2

Immediate Life-Threatening Exclusions (First 10 Minutes)

Obtain a 12-lead ECG within 10 minutes to identify ST-elevation myocardial infarction, new ischemic changes, or the pericarditis pattern of diffuse concave ST-elevation with PR-depression. 1, 2

Measure high-sensitivity cardiac troponin immediately because it is the most sensitive biomarker for myocardial injury, even when the presentation appears non-cardiac. 1, 2, 3

Assess vital signs bilaterally (heart rate, respiratory rate, oxygen saturation, blood pressure in both arms) to detect pulse differentials suggesting aortic dissection or tachycardia/tachypnea indicating pulmonary embolism. 1, 2

Critical Pitfall: Positional Pain Does NOT Exclude Cardiac Ischemia

• Approximately 13% of patients with pleuritic-type chest pain have acute myocardial ischemia, so sharp or positional pain does not rule out acute coronary syndrome. 1, 3
• A completely normal physical examination does not exclude myocardial infarction; uncomplicated MI can present with entirely normal findings. 1, 3
• Women, elderly patients, and those with diabetes frequently present with atypical symptoms including sharp, stabbing, or positional pain. 3

Most Likely Diagnosis: Acute Pericarditis

Diagnostic Criteria (Require ≥2 of 4)

Acute pericarditis is diagnosed when at least two of the following are present: 4, 5, 6

1. Sharp, pleuritic chest pain that worsens supine and improves sitting forward (present in ≈90% of cases) 5, 7, 6
2. Pericardial friction rub on auscultation along the left lower sternal border (present in 18-85% of cases, highly specific but transient) 4, 5, 6, 8
3. ECG changes: diffuse concave ST-segment elevation with PR-segment depression (present in 25-50% of cases) 4, 5, 7, 6
4. New or worsening pericardial effusion on echocardiography (present in ≈60% of cases, most often small) 4, 5, 6

Physical Examination Findings

• Pericardial friction rub is a biphasic or triphasic scratching sound best heard at the left lower sternal border with the patient leaning forward. 2, 6, 8
• Fever commonly accompanies pericarditis but may be absent early in the disease course. 1, 6, 8
• Absence of a friction rub does not exclude pericarditis, as it is transient and may not be present at the time of examination. 1, 5

Electrocardiographic Features

Classic ECG findings evolve through four stages: 7, 6, 8

• Stage 1 (acute): Diffuse concave-upward ST-segment elevation without reciprocal changes, plus PR-segment depression 4, 7, 6
• Stage 2: Normalization of ST and PR segments 7
• Stage 3: T-wave inversions 7, 6
• Stage 4: Resolution of T-wave changes 7

Key distinguishing features from myocardial infarction: 7, 6

• ST elevations are diffuse and concave upward (not convex)
• No reciprocal ST depressions (except in aVR and V1)
• No Q waves develop
• PR depression is characteristic of pericarditis

Alternative Diagnoses to Consider

Gastroesophageal Reflux Disease (GERD)

GERD accounts for 10-20% of chest pain presentations and produces burning retrosternal pain after meals or at night, often worsened by lying flat and relieved by antacids. 1, 3

• Pain duration can be minutes to hours and may worsen with stress. 1
• Esophageal spasm can mimic cardiac ischemia and may respond to nitroglycerin; therefore, nitroglycerin response should NOT be used to differentiate cardiac from esophageal pain. 1, 3
• If pericarditis is excluded and symptoms suggest GERD, a trial of empiric proton-pump inhibitor therapy is reasonable. 1

Pulmonary Embolism

Tachycardia occurs in >90% of PE patients, and dyspnea with pleuritic chest pain is the hallmark presentation. 1, 2, 3

• Use Wells criteria or clinical gestalt to estimate pre-test probability before ordering D-dimer or CT pulmonary angiography. 2
• Absence of dyspnea substantially lowers PE likelihood but does not eliminate it. 9

Pneumothorax

Classic triad includes dyspnea, pleuritic pain on inspiration, and unilateral absence of breath sounds with hyperresonant percussion. 1, 2, 3

Costochondritis

Costochondritis accounts for approximately 43% of chest pain presentations in primary care when cardiac causes are excluded. 2, 3

• Pain is reproducible with palpation of costochondral joints and worsens with chest wall movement, breathing, turning, or twisting. 2, 3
• Up to 7% of patients with reproducible chest wall tenderness still have acute coronary syndrome, so ECG and troponin remain mandatory. 2, 3

Management Algorithm for Confirmed Acute Pericarditis

First-Line Pharmacologic Therapy

High-dose aspirin (500 mg–1 g every 6–8 hours) or ibuprofen (600-800 mg three times daily) should be initiated to reduce pain and inflammation, with doses tapered once chest pain resolves and C-reactive protein normalizes, typically over several weeks. 2, 4, 5, 6

Colchicine (0.5–0.6 mg once or twice daily for 3 months) should be added to reduce symptoms and prevent recurrence (recurrence rate 16.7% with colchicine vs. 37.5% without; absolute risk reduction 20.8%). 2, 4, 5, 6

• For patients weighing <70 kg, use a reduced daily colchicine dose. 2
• With first recurrence, continue colchicine for at least 6 months. 5

Medications to Avoid

Glucocorticoids and non-aspirin NSAIDs should be avoided because they may increase the risk of recurrent myocardial infarction or impair myocardial healing. 2, 4, 5

• Reserve glucocorticoids for patients with contraindications to first-line therapy, pregnancy beyond 20 weeks' gestation, or systemic inflammatory conditions. 4, 6

Diagnostic Imaging

Transthoracic echocardiography should be performed in all patients to determine the presence of pericardial effusion, assess ventricular wall motion, and evaluate for restrictive physiology or tamponade. 1, 4, 6, 8

Cardiac MRI with gadolinium contrast is useful if diagnostic uncertainty exists or to determine the extent of pericardial inflammation and fibrosis. 1, 2

Indications for Hospital Admission

Patients with high-risk features require hospital admission: 4, 5

• Fever >38°C
• Subacute onset (symptoms developing over days to weeks)
• Large pericardial effusion (>20 mm echo-free space)
• Cardiac tamponade
• Failure to respond to NSAIDs after 7 days
• Myopericarditis (elevated troponin)
• Immunosuppression
• Trauma
• Oral anticoagulant therapy

When to Reconsider the Diagnosis

If both troponins (initial and 3-6 hour repeat) are normal, ECG shows no ischemic changes, and pain is not reproducible with palpation, then pericarditis becomes the leading diagnosis when positional features are present. 2, 3, 9

If symptoms persist despite negative cardiac workup, evaluate for gastrointestinal causes such as GERD or esophageal motility disorders. 1

For recurrent episodes without physiological cause after thorough evaluation, consider referral to cognitive-behavioral therapy. 1