What initial tests should be done for a patient with potential cardiac or neurological symptoms?

Initial Testing for Patients with Potential Cardiac or Neurological Symptoms

For patients with potential cardiac or neurological symptoms, initial testing should include brain imaging, vascular imaging, 12-lead ECG, and basic laboratory tests to assess for life-threatening conditions and establish a diagnosis. 1

Core Initial Tests for All Patients

Imaging Studies

• Brain imaging:

  • Non-contrast CT or MRI of the brain 1
  • Should be performed immediately for patients with suspected stroke 1
  • CT is typically faster and more readily available in emergency settings

• Vascular imaging:

  • CTA from aortic arch to vertex (both extracranial and intracranial vasculature) 1
  • Alternatives: Carotid ultrasound and MR angiography if CTA unavailable 1

Cardiac Assessment

• 12-lead ECG 1

  • Essential for all patients with potential cardiac or neurological symptoms
  • Can identify arrhythmias, conduction abnormalities, ischemia, or structural heart disease
  • Heart failure is very unlikely (<2%) in patients with acute presentation and normal ECG 1

• Echocardiography 1

  • Provides information on chamber volumes, ventricular function, wall thickness, valve function
  • Essential for patients with suspected heart failure or structural heart disease
  • Particularly important for patients with syncope and suspected cardiac etiology 1

Laboratory Tests

• Essential blood tests:

  • Complete blood count with platelet count 1, 2
  • Electrolytes and renal function tests 1, 2
  • Blood glucose 1, 2
  • Cardiac enzymes/troponin 1
  • Coagulation studies (PT/INR, aPTT) 1
  • Thyroid-stimulating hormone (TSH) 2

• Additional tests based on clinical suspicion:

  • Lipid profile 1, 2
  • HbA1c or glucose tolerance test 1
  • Hepatic function tests 1
  • Toxicology screen if intoxication suspected 1
  • Arterial blood gases if hypoxia suspected 1

Symptom-Specific Additional Testing

For Suspected Stroke

• National Institutes of Health Stroke Scale (NIHSS) assessment 1
• Chest radiography if lung disease suspected 1
• Lumbar puncture if subarachnoid hemorrhage suspected and CT negative 1

For Suspected Heart Failure

• Natriuretic peptides (BNP or NT-proBNP) 1
• Stress testing if ischemia suspected 1

For Syncope

• Tilt testing for younger patients with recurrent syncope without heart disease 1
• Carotid sinus massage for older patients or those with syncope during neck turning 1
• Prolonged ECG monitoring (Holter, external or implantable loop recorder) for suspected arrhythmic syncope 1

Important Considerations

• Timing is critical: For suspected stroke, thrombolytic therapy should not be delayed while waiting for lab results unless bleeding abnormality is suspected or the patient is on anticoagulants 1

• Prioritize based on presentation:

  • For acute presentations with high-risk features (focal neurological deficits, chest pain, severe dyspnea), brain imaging and cardiac assessment should be performed immediately 1
  • For less acute presentations, testing can be completed within appropriate timeframes based on risk stratification 1

• Common pitfall: Relying solely on normal ECG to rule out cardiac disease. While a normal ECG makes heart failure unlikely in acute presentations (<2%), it has lower negative predictive value in non-acute presentations (10-14%) 1

• Avoid unnecessary testing: Basic laboratory tests are only indicated if syncope may be due to volume loss or if a metabolic cause is suspected 1

By following this structured approach to initial testing, clinicians can efficiently identify life-threatening conditions and establish appropriate diagnoses for patients with potential cardiac or neurological symptoms.