Histopathological insights into mitral valve prolapse-induced fibrosis

Area of Science:

• Cardiology
• Pathology
• Cardiac Imaging

Background:

• Mitral valve prolapse (MVP) is a cardiac valve disease impacting the mitral valve (MV) and leading to left ventricular (LV) structural changes.
• Regionalized fibrosis in the LV, especially in papillary muscles and the inferobasal wall, is a key maladaptive change observed in MVP.
• This fibrosis is hypothesized to result from mechanical stress and altered annular motion, independent of mitral regurgitation (MR) volume-overload effects.

Purpose of the Study:

• To provide an overview of histopathological studies on LV fibrosis and remodeling in MVP patients.
• To elucidate the role of histopathology in quantifying fibrotic remodeling and understanding MVP pathophysiology.
• To review molecular changes, including collagen expression, in MVP.

Main Methods:

• Review of current histopathological studies investigating LV fibrosis and remodeling in MVP.
• Analysis of histopathology's ability to quantify fibrotic remodeling.
• Review of molecular alterations, such as collagen expression.

Main Results:

• Histopathological studies are crucial for understanding LV fibrosis and remodeling in MVP.
• Fibrosis in MVP occurs in valve-linked regions, potentially due to mechanical stress.
• Cardiovascular magnetic resonance (CMR) imaging has limitations in detecting interstitial fibrosis.

Conclusions:

• Regional LV fibrosis in MVP is clinically relevant, associated with arrhythmias and sudden cardiac death, even without significant MR.
• Fibrosis may also contribute to LV dysfunction post-MV surgery.
• Histopathological investigation offers deeper insights into MVP-related fibrosis and molecular changes.