Estimation of left ventricular stroke work based on a large cohort of healthy children

Area of Science:

• Pediatric cardiology
• Biomedical engineering
• Cardiovascular physiology

Background:

• Left ventricular stroke work (LVSW) is a key prognostic indicator of cardiac function.
• Standard LVSW values for pediatric populations are currently lacking.
• Established standards are vital for clinical decision-making in pediatric heart failure and for optimizing cardiovascular medical devices.

Purpose of the Study:

• To estimate left ventricular stroke work (LVSW) in children using modeled pressure-volume loops.
• To develop reference curves for standard LVSW values in healthy children based on age, weight, and height.
• To provide a tool for quantifying and comparing LVSW in pediatric patients.

Main Methods:

• A lumped parameter model was fitted to clinical data from 340 healthy children.
• Left ventricular volume was measured using 3D echocardiography.
• Maximal ventricular pressure was approximated using a regression model; the method was validated against conductance catheter measurements.

Main Results:

• The estimation method showed a low absolute mean difference (0.033 J) and a 21.66% error compared to direct measurements.
• Reference curves indicate LVSW increases from a median of 0.06 J in newborns to 1.15 J at 18 years.
• LVSW demonstrated a similar increasing trend with increasing weight and height, with percentile curves illustrating distribution.

Conclusions:

• This study successfully developed reference curves for pediatric left ventricular stroke work (LVSW).
• The established standards provide a valuable tool for clinicians and engineers in pediatric cardiac assessment and device development.
• The reference curves facilitate the quantification of LVSW differences and comparisons in pediatric patients.