From the Guidelines
Myxomatous degeneration is a pathological process where normal tissue becomes weakened and floppy due to abnormal accumulation of mucopolysaccharides in the extracellular matrix, most commonly affecting the mitral valve and leading to mitral valve prolapse. This condition occurs when fibroblasts produce excessive amounts of proteoglycans, causing the tissue to lose its normal architecture and mechanical properties 1. The degeneration can affect other connective tissues throughout the body, including tendons, ligaments, and the aortic wall.
Key Characteristics
- The condition is often genetic but can also develop with aging or as part of certain connective tissue disorders like Marfan syndrome 1.
- Myxomatous degeneration can lead to significant regurgitation or other cardiac complications, necessitating surgical repair or replacement in severe cases 1.
- Regular cardiac monitoring is crucial for patients with known myxomatous changes to track disease progression 1.
Clinical Implications
- Mitral valve prolapse (MVP) is mostly associated with myxomatous degeneration of the valve, and can lead to mitral regurgitation, rhythm disorders, endocarditis, syncope, or embolism 1.
- The natural history of asymptomatic MVP is heterogeneous and can vary from benign and normal life expectancy to adverse with significant morbidity or mortality 1.
- Severe myxomatous degeneration of heart valves may eventually necessitate surgical repair or replacement if it causes significant regurgitation or other cardiac complications.
Management and Prevention
- Patients with myxomatous degeneration should be closely monitored for disease progression and cardiac complications 1.
- Surgical intervention may be necessary in severe cases, and intraoperative transesophageal echocardiography can be used to evaluate the results of mitral valve repair or replacement 1.
From the Research
Definition of Myxomatous Degeneration
- Myxomatous degeneration, also known as myxomatous mitral valve disease (MMVD), is a condition characterized by the degeneration of the mitral valve, leading to mitral regurgitation 2, 3, 4, 5.
- This condition involves the morphological changes of the mitral valve, including the thickening and prolapse of the valve leaflets, as well as the dilation and displacement of the mitral annulus 3, 4.
Pathophysiology of Myxomatous Degeneration
- The pathophysiology of myxomatous mitral valve degeneration is complex and involves the activation and transformation of mitral valve valvular interstitial cells (VICs) into an active phenotype, leading to remodeling of the extracellular matrix and compromise of the structural components of the mitral valve leaflets 5.
- The neurotransmitter serotonin (5HT) and transforming growth factor beta (TGF-β) have been linked to the development of myxomatous mitral valve degeneration, and understanding their role may lead to potential therapies 5.
Clinical Significance of Myxomatous Degeneration
- Myxomatous degeneration is a leading cause of valve repair or replacement, and can lead to mitral regurgitation, cardiac enlargement, systolic dysfunction, and heart failure 2, 3, 5.
- The condition can also be associated with ventricular arrhythmias and sudden cardiac death, particularly in cases with mitral annular disjunction (MAD) 4.
Treatment and Management of Myxomatous Degeneration
- Mitral valve repair is the procedure of choice for treating myxomatous degeneration, and can provide excellent early functional results, although late recurrent regurgitation is common 2, 3.
- Beta-blockers may also have a role in the management of patients with valvular disorders, including those with myxomatous degeneration, although their use is not specifically tailored to this condition 6.