Ejection Fraction in the Fast Lane

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Cardiac Mechanics

Background:

• Ventricular performance is commonly assessed using pressure, volume, and flow measurements.
• Traditional metrics like ejection fraction (EF) are dimensionless ratios and may be incomplete.
• Existing EF variations, such as first-third EF (⅓EF) and first-phase EF1, have limitations.

Purpose of the Study:

• To introduce a novel, more powerful metric for evaluating ventricular performance.
• To address the limitations of existing dimensionless metrics like EF.
• To propose a metric with physical units for a more complete assessment.

Main Methods:

• Utilized representative recordings from a chronically instrumented conscious dog model.
• Analyzed early events during ejection time (ET).
• Developed the Kerkhof-Diaz-Handly (KDH) metric based on these analyses.

Main Results:

• The KDH metric was proposed as a more powerful alternative to traditional EF.
• The KDH metric possesses physical units, unlike dimensionless EF ratios.
• The study highlights the variability of the diastolic phase (TD) in the cardiac cycle.

Conclusions:

• The KDH metric offers a more complete and physically meaningful assessment of ventricular performance.
• This new metric overcomes the inherent limitations of dimensionless ratios.
• Further investigation into the KDH metric could enhance cardiovascular diagnostics.