Unraveling the complexity of paravalvular leak: The Power of 4D Flow MRI in a Challenging Case (QF_SA_140)

Saturday, February 1, 2025

8:10 AM – 8:20 AM East Coast USA Time

Location: Blue Room PreFunction - Kiosk 1

Presenting Author(s)

RV

Ricardo Villamarin, MD

Cardiac Imaging Fellow
Instituto Nacional de Cardiología Ignacio Chavez, Mexico

Primary Author(s)

RV

Ricardo Villamarin, MD

Cardiac Imaging Fellow
Instituto Nacional de Cardiología Ignacio Chavez, Mexico

Co-Author(s)

MC

Miguel Cruz, MD

Medical physician of cardiac magnetic resonance
National Institute of Cardiology "Ignacio Chávez", Mexico
AM

Aloha Meave Gonzalez, MD

Chair
Instituto Cardiologia, Mexico

Description of Clinical Presentation: A 67-year-old male patient with a history of severe symptomatic aortic stenosis was admitted for transcatheter aortic valve replacement (TAVR) due to high surgical risk. The initial procedure was performed without major complications.

During the first days after the procedure, the patient presented an irregular clinical course with the development of a fever of 38.5°C accompanied by general malaise and chills. Blood cultures were performed and were positive for gram-positive cocci, confirming bacteremia. Targeted antibiotic treatment was initiated.

Given the persistence of symptoms and the clinical scenario, it was decided to perform a detailed evaluation by cardiac magnetic resonance with 4D flow to assess valve function and rule out complications. Imaging studies revealed a significant paravalvular leak in the lateral region of the prosthesis, which explained the hemodynamic instability and inadequate evolution.

Diagnostic Techniques and Their Most Important Findings:

1. Significant paravalvular leak: A paravalvular leak was identified between the prosthetic valve and the right coronary sinus. The regurgitant jet was clearly and directly observed with turbulent flow extending into the aortic root, confirming abnormal communication contributing to left ventricular volume overload.

2. Quantification of Regurgitant Flow: Quantitative flow assessment showed mild to moderate regurgitant volume (RF 20%), suggesting a possible relevant hemodynamic impact that could contribute to the patient's persistent symptoms.

3. Assessment of ventricular function: Preserved global left ventricular systolic function was observed with EF 52%. There was no evidence of significant dysfunction in other ventricles.

4. Vascular anatomy and relationship to the prosthesis: The study highlighted the critical proximity of the leak to the right coronary sinus, which may have facilitated the formation of the regurgitant jet. There was no evidence of thrombosis or vegetation associated with the valve.

5. Ascending aortic reflux: Detailed analysis revealed significant ascending aortic reflux that correlated with the direction and severity of the paravalvular leak. These findings were critical for planning further therapeutic interventions.

Learning Points from this Case:

1. Importance of Comprehensive Post-TAVI Evaluation: 4D flow MRI is a potential tool to identify and characterize paravalvular leaks.

2. Specific location of the leak: Accurate identification of the paravalvular leak underscores the ability of 4D Flow MRI to map the anatomy and direction of the regurgitant jet, which is essential for clinical management and intervention planning.

3. Quantification of hemodynamic impact: Detailed analysis of regurgitant flow allows quantitative assessment of leak severity, providing critical information on left ventricular volume overload.

4. Guide multidisciplinary management: 4D Flow MRI findings can aid decision making in a multidisciplinary setting, highlighting its role not only in diagnosis but also in guiding future interventions to correct paravalvular leak.

5. Relevance to clinical practice: This case highlights the importance of advanced imaging in the evaluation of post-procedural complications and how 4D flow MRI can change the treatment approach and improve patient outcomes.