Echocardiographic definition of the left ventricular centroid. I. Analysis of methods for centroid calculation from a...

Area of Science:

• Cardiovascular Physiology
• Biomedical Imaging Analysis
• Cardiac Mechanics

Background:

• Accurate quantitation of myocardial contraction necessitates a stable reference frame.
• Identifying a reliable centroid for the left ventricle is challenging due to the absence of clear anatomical landmarks.
• Previous studies explored fixed vs. floating reference frames, but defining the optimal centroid calculation method remains unresolved.

Purpose of the Study:

• To evaluate and compare various methods for defining the left ventricular centroid.
• To determine the most reproducible and accurate method for centroid calculation through variance analysis.
• To establish a standardized approach for reference frame selection in myocardial motion analysis.

Main Methods:

• Digitization of endocardial and epicardial borders from canine cardiac cycles by two observers.
• Calculation of the left ventricular centroid using six distinct methods (coordinate-based and area-based).
• Analysis of variance (ANOVA) applied to centroid path correlations across observers, cycles, and animals.

Main Results:

• Significant variations in centroid path reproducibility were observed among the six tested methods.
• The 'center of endocardial area' method demonstrated the lowest observer-to-observer and cycle-to-cycle variance.
• This area-based method proved superior in minimizing variability compared to coordinate-based approaches.

Conclusions:

• The 'center of endocardial area' is the most robust method for defining the left ventricular centroid.
• This finding provides a more reliable reference frame for quantitating myocardial contraction and assessing cardiac function.
• Standardizing centroid definition enhances the accuracy and comparability of cardiovascular research.