Regional LV Contractility: 17-Segment Model, Dysfunction Scale, and WMSI Index
Note: The provided SOURCE FRAGMENTS block does not contain factual data regarding the 17-segment division model of the LV, the semi-quantitative scoring scale for segmental contractility dysfunction (normokinesis/hypokinesis/akinesis/dyskinesis), and the method for calculating the regional contractility dysfunction index (WMSI). Only those provisions directly confirmed by the available fragments are presented below.
What is confirmed by the source
When examining the LV along the long axis (LAX LV) in M-mode, it is recommended to assess the movement of the LV walls according to the phases of the cardiac cycle and to exclude contractility dysfunction, dyssynchrony, and paradoxical wall motion (when the walls move parallel in the same direction) [Blagodir B.V., 2024].
In the basic assessment of the LV, it is recommended to measure wall thickness, chamber sizes, global function, and valve function, as well as to exclude chamber dilation, wall thickening, contractility dysfunction, and valve anomalies [Blagodir B.V., 2024].
According to ASE and EACVI recommendations (2015 update, J Am Soc Echocardiogr 2015; 28:1–39), linear dimensions should be measured in 2D mode, avoiding M-mode due to possible oblique angles when obtaining one-dimensional images [Blagodir B.V., 2024].
Data missing from the fragments
| Topic Element | Status in Source |
|---|---|
| 17-segment LV model | [clarification needed] — absent |
| Scoring scale (normo-/hypo-/a-/dyskinesis) | [clarification needed] — absent |
| Formula and thresholds of WMSI | [clarification needed] — absent |
For a correct presentation of the 17-segment model, scoring scale, and WMSI calculation, a specialized source is required (e.g., ASE/EACVI recommendations for cardiac chamber quantification), which is only indirectly referenced in the provided fragments [clarification needed].
Frequently asked questions
Is there a description of the 17-segment LV model in the fragments?
No. The provided fragments do not contain data on the 17-segment model [clarification needed].
What regional contractility dysfunctions are mentioned in the source?
It is indicated that contractility dysfunction, dyssynchrony, and paradoxical wall motion (when the walls move parallel in the same direction) should be excluded when assessing LAX LV in M-mode [Blagodir B.V., 2024].
Is the WMSI formula provided in the fragments?
No. The calculation method and threshold values of WMSI are not presented in the fragments [clarification needed].
In which mode is it recommended to measure linear LV dimensions?
In 2D mode, avoiding M-mode due to oblique angles in one-dimensional images (ASE/EACVI, 2015 update).