What could be causing left upper chest pain that worsens with deep inhalation (exhale)?

Left Upper Chest Pain Worsening with Deep Exhalation

Your left upper chest pain that worsens with deep breathing most likely represents either pleuritic pain from a pulmonary cause (pneumonia, pleurisy, pulmonary embolism) or musculoskeletal chest wall pain (costochondritis, muscle strain), but you must immediately rule out life-threatening conditions including pulmonary embolism, pneumothorax, and acute coronary syndrome before attributing symptoms to benign causes. 1, 2

Immediate Life-Threatening Conditions to Exclude First

Call 9-1-1 immediately if you experience any of the following: 1, 3

• Severe dyspnea or inability to catch your breath
• Diaphoresis (cold sweats), lightheadedness, or syncope
• Sudden onset of severe "ripping" or "tearing" pain
• Tachycardia or feeling your heart racing

Pulmonary Embolism

• Pulmonary embolism presents with tachycardia and dyspnea in >90% of patients, with pain that occurs with inspiration. 1, 2, 4
• Risk factors include recent immobilization, oral contraceptives, long flights, or family history of clotting disorders. 4
• This is found in 5-21% of emergency department presentations with pleuritic chest pain. 4

Pneumothorax

• Look for unilateral absence of breath sounds on the affected side, dyspnea, and sharp pain with inspiration. 1, 4
• More common in tall, thin young males and those with a history of vaping. 4

Acute Coronary Syndrome

• While ACS typically does not worsen specifically with breathing, it can present atypically, particularly in women, elderly, or diabetic patients. 1, 3
• The American College of Cardiology states that chest tenderness on palpation or pain with inspiration markedly reduces the probability of ACS, but does not eliminate it. 1, 4

Most Likely Benign Causes

Musculoskeletal (Costochondritis/Chest Wall Strain)

• The European Heart Journal reports that musculoskeletal problems cause 43% of chest pain in general practice settings, making this the most common overall cause. 1
• Tenderness of costochondral joints on palpation is diagnostic for costochondritis. 1
• Pain typically worsens with specific movements, deep breathing, coughing, or direct pressure on the chest wall. 1, 5
• Systematic palpation of the costal margin can diagnose painful rib syndrome with high specificity. 4

Pleurisy/Pleuritis

• Pleuritic chest pain is characterized by sharp, localized pain that worsens with deep inspiration or coughing. 6, 7
• The visceral pleura is insensate, so pain arises from irritation or inflammation of the parietal pleura. 6
• May be viral (benign) or associated with pneumonia. 7

Pneumonia

• Pneumonia presents with fever, localized chest pain that may be pleuritic, friction rub, regional dullness to percussion, and egophony. 1, 2

Diagnostic Algorithm

Step 1: Immediate Assessment (If Seeking Medical Care)

• An ECG should be obtained within 10 minutes to exclude ST-segment elevation myocardial infarction. 1, 2
• Cardiac troponin should be measured as soon as possible if presenting to emergency department. 1, 2
• Obtain chest X-ray immediately to evaluate for pneumothorax, pneumonia, pleural effusion, or infiltrates. 4

Step 2: Physical Examination Findings

• Perform focused cardiovascular and respiratory examination, checking vital signs and auscultating for unilateral absence of breath sounds or crackles. 1, 4
• Palpate chest wall systematically for reproducible tenderness to diagnose musculoskeletal pain. 1, 4
• Check for fever, which suggests infectious etiology (pneumonia) or inflammatory process (pericarditis). 1

Step 3: Risk Stratification

• If pain is reproducible with palpation AND there are no high-risk features (dyspnea, tachycardia, fever, risk factors for PE), musculoskeletal cause is most likely. 1, 4
• If dyspnea and tachycardia are present, consider D-dimer only if clinical prediction rule suggests PE is possible. 4

Critical Pitfalls to Avoid

• Do not use nitroglycerin relief as a diagnostic criterion for cardiac vs non-cardiac pain, as esophageal spasm and other conditions also respond to nitroglycerin. 2, 3
• Do not assume a normal examination excludes serious pathology—pulmonary embolism and even acute coronary syndrome can present with minimal physical findings. 1, 2
• Do not delay transfer to emergency department for troponin or diagnostic testing if acute coronary syndrome is suspected. 1, 2
• Do not dismiss cardiac causes in women, elderly, or diabetic patients who frequently present with atypical symptoms including sharp or positional pain. 3

When to Seek Immediate Medical Attention

You should activate 9-1-1 or go to the emergency department immediately if: 1, 3

• Pain is severe or interrupts normal activity
• Associated with dyspnea, cold sweats, nausea, vomiting, or lightheadedness
• Sudden onset with severe intensity
• Unilateral absence of breath sounds or difficulty breathing
• Any concern for pulmonary embolism risk factors

If symptoms are mild, reproducible with palpation, and no high-risk features are present, you may follow up with your primary care provider within 24-48 hours for evaluation of likely musculoskeletal cause. 1