What are the immediate steps to rule out pulmonary embolism, pericarditis, or aortic dissection in a patient with intermittent chest pain after angioplasty?

Diagnostic Approach to Rule Out Pulmonary Embolism, Pericarditis, or Aortic Dissection

For patients with intermittent chest pain after angioplasty, a systematic diagnostic approach using specific imaging studies is essential to rule out life-threatening conditions like pulmonary embolism, pericarditis, or aortic dissection.

Initial Assessment

• Perform a focused physical examination checking vital signs (consciousness, respiration, blood pressure, heart rate, body temperature) to identify signs of hemodynamic instability 1
• Obtain an ECG within 10 minutes of presentation to identify ST-segment changes, signs of pericarditis, or other abnormalities 1
• Draw blood for laboratory tests including troponin, complete blood count, CRP, arterial blood gas, and creatinine 1

Specific Diagnostic Tests for Each Condition

For Aortic Dissection

• Use the ADD (Aortic Dissection Detection) score to assess probability of aortic dissection 1
• Look for physical findings such as pulse differential between extremities (though sensitivity is only about 30%) 1
• Perform transthoracic echocardiography (TTE) as an initial imaging modality 1
• If TTE is inconclusive or positive, proceed to:
  • Transesophageal echocardiography if aortic dissection is suspected 1
  • CT or MRI scan for definitive diagnosis of aortic dissection 1

For Pulmonary Embolism

• Use validated clinical prediction scores to determine the likelihood of pulmonary embolism 1
• Perform point-of-care focused cardiac ultrasound (FoCUS) to look for right ventricular dilation and D-shaped left ventricle in short-axis view 2
• Order pulmonary scintigraphy or spiral CT examination for definitive diagnosis 1
• Monitor oxygen saturation and establish intravenous access during evaluation 1

For Pericarditis

• Look for characteristic ECG changes and pleuritic chest pain that increases in the supine position 1
• Perform transthoracic echocardiography to assess for pericardial effusion, which may indicate pericarditis 1, 2
• Consider that pericarditis can sometimes be the initial manifestation of aortic dissection, especially in younger patients 3

Special Considerations After Angioplasty

• Be aware that chest pain after coronary interventional procedures is common and may be due to:
  • Coronary artery spasm (4.2% of cases)
  • Coronary occlusion (4.6% of cases)
  • Myocardial infarction (4.8% of cases)
  • Non-ischemic "stretch pain" from arterial wall stretching, especially after stent placement 4

Diagnostic Algorithm

1. If hemodynamically unstable:

   • Perform immediate bedside echocardiography (EASY screening protocol) to assess for:
     • Effusion in pericardial space (suggesting pericarditis or aortic dissection)
     • Aortic abnormalities (suggesting aortic dissection)
     • Ventricle size and shape (right ventricular dilation suggesting pulmonary embolism)
     • Left ventricular wall motion abnormalities 2
   • Proceed to definitive imaging based on echocardiographic findings

2. If hemodynamically stable:

   • Complete the initial assessment (physical exam, ECG, laboratory tests)
   • Perform chest X-ray to rule out other causes of chest pain 1
   • Proceed with transthoracic echocardiography 1
   • Based on clinical suspicion and initial findings, order:
     • CT angiography for suspected pulmonary embolism or aortic dissection 1
     • Additional cardiac testing as indicated

Management During Diagnostic Workup

• Provide appropriate pain relief with opioids if pain is severe 1
• Monitor vital signs continuously 1
• Be prepared for rapid intervention if patient condition deteriorates 1
• Transfer unstable patients to appropriate level of care (ICU, cardiac care unit) 1

Caution

• Do not delay transfer to emergency department for diagnostic testing if patient is initially evaluated in an office setting 1
• Remember that post-angioplasty chest pain may be benign but requires thorough evaluation to rule out life-threatening causes 4
• Consider that these conditions can coexist - one study reported a case of simultaneous acute myocardial infarction, aortic dissection, and pulmonary embolism 5