[Quantification of the function of the left ventricle using 2-dimensional echocardiography]

Area of Science:

• Cardiovascular Imaging
• Diagnostic Ultrasound
• Cardiac Physiology

Context:

• Two-dimensional echocardiography (2D echo) is a key imaging modality for assessing cardiac function.
• Establishing reliable normal values is crucial for accurate interpretation of 2D echo parameters.
• Methodological differences prevent direct transfer of cineventriculographic normal values to 2D echo.

Purpose:

• To establish normal reference values for left ventricular volumes and ejection fraction using 2D echo in healthy individuals.
• To determine the diagnostic accuracy (sensitivity, specificity, predictive accuracy) of 2D echo for detecting impaired left ventricular function.
• To analyze variability (beat-to-beat, day-to-day, intraobserver, interobserver) and establish criteria for significant changes in 2D echo measurements.

Summary:

• Normal values for left ventricular volumes and ejection fraction were established in 55 controls using 2D echo.
• 2D echo demonstrated high sensitivity (84%), specificity (89%), and predictive accuracy (98%) for detecting reduced ejection fraction compared to cineventriculography.
• Analysis revealed optimal beat-to-beat evaluation requires 3 consecutive beats, and significant individual changes exceed 10-12% for volumes and 10% for ejection fraction. Interobserver variability was noted for specific views.

Impact:

• 2D echo serves as a reliable screening tool for left ventricular function assessment.
• The established normal values and variability analysis enhance the clinical utility and interpretation of 2D echo.
• Findings support the use of 2D echo in pharmacodynamic studies by focusing on percentage changes.