[Pathoetiological aspects of mitral valve prolapse].

Area of Science:

• Cardiovascular Pathology
• Histology
• Electron Microscopy

Context:

• Myxomatous degeneration of the mitral valve is a primary factor in mitral valve prolapse (MVP).
• Understanding the pathological characteristics of myxomatous lesions is crucial for diagnosing and managing MVP.
• This study investigates the extent and histological features of myxomatous lesions in various cardiac conditions.

Purpose:

• To analyze and compare the area and histological characteristics of myxomatous lesions in the mitral valve across different patient groups.
• To determine the specific pathological findings associated with idiopathic MVP.
• To investigate the secondary development of myxomatous lesions in conditions like hypertension and right ventricular hypertrophy.

Summary:

• Myxomatous lesions in mitral valve leaflets were quantified and analyzed histologically and electron-microscopically in idiopathic MVP, secondary MVP, hypertension, right ventricular hypertrophy, and control groups.
• Idiopathic MVP cases exhibited significantly larger myxomatous lesions (≥50% area) compared to other conditions.
• Histological analysis revealed diffuse lesions, loss of collagen, and disrupted elastic fibers, replaced by mesenchymal cells in electron microscopy, indicating active pathological remodeling.

Impact:

• The findings highlight that increased myxomatous lesion is an essential pathological hallmark of idiopathic MVP.
• This research clarifies that while myxomatous lesions are characteristic of idiopathic MVP, they can also develop secondarily in other cardiovascular conditions, albeit to a lesser extent.
• Provides a deeper understanding of the pathophysiology of mitral valve prolapse, aiding in differential diagnosis and potential therapeutic strategies.