Load-Independent Indices of Left Ventricular Function Using Automated Border Detection

Area of Science:

• Cardiovascular imaging
• Echocardiography
• Cardiac physiology

Background:

• Automated border detection in echocardiography enables assessment of left ventricular (LV) cross-sectional cavity areas and volumes.
• This facilitates the use of LV pressure-volume relationships for determining LV function, largely independent of loading conditions.

Purpose of the Study:

• To review validation studies of LV cross-sectional area as a surrogate for LV volume in animal models and humans.
• To discuss clinical applications of LV pressure-area relations.
• To explore the use of arterial pressure as a substitute for LV ejection pressure and assess right ventricular performance using pressure-area relations.
• To discuss preload-adjusted maximal power as a load-insensitive method for LV performance assessment.

Main Methods:

• Review of existing validation studies on echocardiographic automated border detection.
• Analysis of clinical applications of LV pressure-area relations.
• Evaluation of the use of arterial pressure and preload-adjusted maximal power in assessing cardiac function.

Main Results:

• LV cross-sectional area has been validated as a surrogate for LV volume.
• LV pressure-area relations provide a load-independent assessment of LV function.
• Arterial pressure can substitute for LV ejection pressure in pressure-area relation analysis.
• Pressure-area relations and preload-adjusted maximal power offer alternative methods for evaluating cardiac performance.

Conclusions:

• Echocardiographic automated border detection and LV pressure-area relations offer valuable, load-independent methods for assessing cardiac function.
• These techniques have broad clinical applications for both left and right ventricular performance evaluation.
• Preload-adjusted maximal power presents a promising alternative for load-insensitive assessment of LV performance.