MRI of perivalvular infectious pseudoaneurysms

Area of Science:

• Cardiovascular Imaging
• Infectious Diseases
• Medical Diagnostics

Background:

• Infective endocarditis complicating cardiac surgery can lead to serious complications like perivalvular pseudoaneurysms.
• Accurate and timely diagnosis of these pseudoaneurysms is crucial for effective patient management.
• Traditional imaging modalities may have limitations in visualizing these complex structures, especially in the presence of prosthetic materials.

Purpose of the Study:

• To evaluate the utility of Magnetic Resonance Imaging (MRI) in detecting and characterizing perivalvular infectious pseudoaneurysms.
• To assess the precision of MRI in localizing these pseudoaneurysms in relation to cardiac structures.
• To highlight the advantages of MRI over other imaging techniques in this specific clinical scenario.

Main Methods:

• Retrospective analysis of three patients with infective endocarditis following cardiac surgery.
• Utilization of cardiac-gated MRI sequences to visualize perivalvular regions.
• Assessment of signal characteristics within pseudoaneurysms to infer blood flow.

Main Results:

• MRI successfully identified perivalvular infectious pseudoaneurysms in all three patients.
• Absence of MR signal within the pseudoaneurysms indicated free blood flow, consistent with abscess cavities.
• Precise localization of pseudoaneurysms was achieved: between the aortic root and left atrium, in the ventricular septum outflow, and surrounding a Rastelli conduit.

Conclusions:

• MRI is a valuable non-invasive tool for diagnosing perivalvular infectious pseudoaneurysms.
• MRI offers precise anatomical localization and demonstrates blood flow dynamics within these lesions.
• Advantages include independence from IV contrast, lack of artifacts from prosthetic valves, and accurate site determination.