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Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat
07:46

Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat

Published on: June 4, 2012

Infected aortic aneurysm, purulent pericarditis, and pulmonary trunk rupture caused by methicillin-resistant

Shunei Saito1, Akio Matsuura, Ken Miyahara

  • 1Division of Cardiovascular Surgery, Aichi Cardiovascular and Respiratory Center, Ichinomiya, Aichi, Japan. shunei0110@ybb.ne.jp

General Thoracic and Cardiovascular Surgery
|May 15, 2009
PubMed

Insights

A severe infection caused by Methicillin-resistant Staphylococcus aureus led to cardiac tamponade and a mycotic pseudoaneurysm. Despite surgical intervention, extensive aortic infection resulted in a fatal outcome.

Area of Science:

  • Cardiology
  • Infectious Diseases
  • Vascular Surgery

Background:

  • Cardiac tamponade is a life-threatening condition requiring prompt diagnosis and management.
  • Mycotic pseudoaneurysms, particularly of the aortic arch, pose significant surgical challenges due to infection and potential rupture.
  • Staphylococcus aureus is a common pathogen in serious infections, including those affecting the cardiovascular system.

Observation:

  • A 66-year-old woman presented with purulent pericarditis and cardiac tamponade.
  • Enhanced CT revealed a saccular aortic arch aneurysm with an adjacent mass suggestive of a mycotic pseudoaneurysm.
  • Post-drainage, massive bleeding occurred, revealing a pulmonary trunk perforation and extensive infection of the aorta.

Findings:

  • Methicillin-resistant Staphylococcus aureus (MRSA) was identified as the causative agent in pericardial effusion, blood, and aortic thrombus.
  • The patient experienced massive hemorrhage from a pulmonary trunk perforation secondary to the infection.
  • Extensive infection of the ascending aorta and aortic arch precluded surgical repair.

Implications:

  • This case highlights the aggressive nature of MRSA infections in the cardiovascular system, leading to complex complications like mycotic pseudoaneurysms and aortic perforation.
  • Prompt recognition and aggressive management are crucial, but outcomes can be poor in cases of extensive aortic involvement.
  • The study underscores the importance of considering infectious etiologies in patients with aortic aneurysms and signs of systemic infection.

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