The Wilkins Score, also known as the Echocardiographic Scoring System for mitral stenosis, is used to assess the suitability of the mitral valve for Percutaneous Mitral Balloon Commissurotomy (PMBC). Developed by Wilkins et al., this scoring system evaluates the morphology of the mitral valve using echocardiographic features and provides a numerical score to guide the decision-making process for intervention.
The Wilkins Score assesses four key aspects of the mitral valve on a scale from 1 to 4 for each feature, with higher scores indicating more extensive disease. The four features include leaflet mobility, leaflet thickening, leaflet calcification, and subvalvular apparatus thickening.
Components of the Wilkins Score
- Leaflet Mobility
- Evaluates how freely the mitral valve leaflets move during diastole.
- Score:
- 1 = Highly mobile valve with only the leaflet tips restricted.
- 2 = Mobility of the leaflets is mostly preserved but with mild restriction of motion.
- 3 = Moderately restricted motion of the entire leaflet.
- 4 = Severely restricted mobility with little or no movement of the leaflets.
- Leaflet Thickening
- Assesses the degree of thickening of the mitral valve leaflets.
- Score:
- 1 = Leaflets are near normal in thickness (4-5 mm or less).
- 2 = Mild leaflet thickening (5-8 mm).
- 3 = Moderate leaflet thickening (8-10 mm).
- 4 = Severe thickening (>10 mm).
- Leaflet Calcification
- Measures the extent of calcium deposits within the leaflets, which affects leaflet flexibility and increases the risk of complications during PMBC.
- Score:
- 1 = No calcification.
- 2 = Mild scattered calcification in the leaflets.
- 3 = Moderate calcification without extending throughout the entire leaflet.
- 4 = Extensive calcification affecting most of the leaflet.
- Subvalvular Apparatus Thickening
- Looks at the condition of the chordae tendineae and papillary muscles that support the mitral valve.
- Score:
- 1 = Minimal or no thickening of the subvalvular structures.
- 2 = Mild thickening below the leaflets.
- 3 = Moderate thickening, extending halfway to the papillary muscles.
- 4 = Severe thickening, extending down to the papillary muscles.
Calculating the Wilkins Score
- The Wilkins Score is the sum of the scores from each of the four components, giving a range from 4 to 16.
- Score 4-8: Considered favorable for PMBC, as this usually indicates mild structural abnormalities in the valve.
- Score >8: Less favorable for PMBC due to extensive leaflet and subvalvular apparatus changes, suggesting limited success and higher risk of complications.
Interpretation and Clinical Use
| Wilkins Score Range | Suitability for PMBC | Clinical Implications |
| 4–8 | Favorable for PMBC | Higher likelihood of successful PMBC with low complication risk. |
| 9–11 | Intermediate Suitability | PMBC may still be considered but with cautious evaluation. |
| >12 | Unfavorable for PMBC | High risk of complications; alternative treatments such as MVR are typically considered. |
Limitations of the Wilkins Score
While the Wilkins Score provides valuable guidance, it has some limitations:
- Does Not Include Commissural Fusion: Commissural fusion, common in rheumatic mitral stenosis, can also impact PMBC outcomes but is not scored in the Wilkins system.
- Operator Dependency: The score is based on echocardiographic interpretation, which can vary between operators.
- Does Not Predict Long-Term Outcomes: The score primarily predicts immediate success and complications but may not reflect long-term durability.