Can mural thrombi cause fever?

Can Mural Thrombi Cause Fever?

Mural thrombi themselves are generally non-pyrogenic, but can be associated with fever in specific clinical scenarios, particularly when infected or when part of an underlying inflammatory condition. 1

Relationship Between Mural Thrombi and Fever

Primary Mechanisms

• Infected thrombi: Mycotic (infected) aneurysms with mural thrombi frequently present with fever (65-85% of cases) and leukocytosis 1
• Inflammatory response: Mural thrombi can trigger fever through:
  • Post-implantation syndrome
  • Arterial wall inflammation
  • Systemic inflammatory response with cytokine release 1

Epidemiology

• Approximately 10% of patients with left ventricular thrombus following myocardial infarction may develop fever 1
• Fever is present in ≥70% of cases with infected aortic mural thrombi 1
• Patients with inflammatory bowel disease may develop aortic mural thrombi associated with systemic inflammation and fever 1

Diagnostic Approach for Fever in Patients with Mural Thrombi

When a patient with known mural thrombus presents with fever, a systematic evaluation is essential:

1. Imaging assessment:

   • CTA or MRI to assess thrombus characteristics and look for signs of infection 1
   • Evaluate for thrombus mobility, which may indicate higher risk for complications

2. Laboratory evaluation:

   • Blood cultures (essential to rule out infection)
   • Inflammatory markers (CRP, ESR, WBC count)
   • Coagulation studies 1

3. Differential diagnosis - Consider other causes of fever:

   • Endocarditis (present in 2.2-7.1% of catheter-related thrombi) 1
   • Pulmonary infarction
   • Venous thromboembolism
   • Underlying inflammatory conditions 1

Management Approach

For Infected Mural Thrombi

1. Antibiotic therapy based on culture results 1
2. Surgical intervention may be necessary in cases of:
   • Persistent fever despite appropriate antibiotics
   • Recurrent embolization
   • Mobile thrombi 1

For Non-Infected Mural Thrombi

1. Anticoagulation therapy:

   • Oral anticoagulation with target INR 2.0-3.0 for at least 3 months for LV mural thrombi 1
   • Anticoagulation has been shown to be effective for aortic mural thrombi 2

2. Monitor for resolution:

   • Serial imaging to assess thrombus resolution
   • Anticoagulation therapy has shown resolution of aortic mural thrombi at a median of 60 days 2

Special Considerations

• Hypercoagulable states: Many patients with aortic mural thrombi in the absence of aortic disease have underlying coagulation disorders 2
• Embolic risk: Untreated mural thrombi carry significant risk of embolization, with studies showing up to 86% embolic events within three months in untreated left ventricular thrombi 3
• Treatment efficacy: Anticoagulation therapy alone allows resolution of aortic mural thrombi in most cases, with surgical intervention reserved for management of end-organ ischemia 2

Pitfalls to Avoid

• Misattribution of fever: Don't assume fever is always due to the thrombus itself; thorough evaluation for other sources is critical 1
• Delayed diagnosis: Fever in a patient with known cardiovascular disease should prompt evaluation for mural thrombus, especially if accompanied by embolic phenomena
• Inadequate follow-up: Serial imaging is essential to monitor thrombus resolution and detect complications early

Remember that while mural thrombi themselves are not typically primary causes of fever, the presence of fever in a patient with mural thrombus should prompt a thorough evaluation for infection or other underlying inflammatory conditions.