Myocardial remodelling in aortic regurgitation: time to think beyond volumes and function?

Area of Science:

• Cardiology
• Cardiovascular Imaging
• Medical Guidelines

Background:

• Current guidelines for aortic regurgitation (AR) surgery use fixed thresholds for left ventricular size and ejection fraction.
• These metrics may not detect early myocardial injury or account for patient variability, especially in women and older adults.

Purpose of the Study:

• To review the limitations of current AR surgical guidelines.
• To compare echocardiography and cardiovascular magnetic resonance (CMR) for AR assessment.
• To explore myocardial fibrosis detected by CMR as a biomarker for risk stratification and personalized intervention timing.

Main Methods:

• Narrative review of existing literature.
• Comparison of echocardiographic and CMR techniques for assessing AR.
• Summary of observational studies linking CMR-detected fibrosis to clinical outcomes and reverse remodeling post-intervention.

Main Results:

• CMR provides robust quantification of AR, ventricular volumes, and myocardial fibrosis (focal and diffuse).
• CMR-detected fibrosis is associated with poorer outcomes and less favorable reverse remodeling after aortic valve intervention.
• Fibrosis may indicate the transition from compensated overload to irreversible myocardial damage.

Conclusions:

• Myocardial fibrosis identified by CMR shows promise as an imaging biomarker for risk stratification in chronic AR.
• Integrating CMR fibrosis metrics with volumetric and functional data could personalize the timing of aortic valve intervention.
• Prospective studies are needed to validate fibrosis-guided decision-making for improved patient outcomes and preserved ventricular function.