Comparison between Modelflow® and echocardiography in the determination of cardiac output during and following pregnancy at rest and during exercise




Prenatal, Submaximal exercise, Finger photoplethysmography, Validity


During pregnancy, assessment of cardiac output (Q ̇), a fundamental measure of cardiovascular function, provides important insight into maternal adaptation. However, methods for dynamic Q ̇ measurement require validation. The purpose of this study was to estimate the agreement of Q ̇ measured by echocardiography and Modelflow® at rest and during submaximal exercise in non-pregnant (n = 18), pregnant (n = 15, 22-26 weeks gestation) and postpartum women (n = 12, 12-16 weeks post-delivery). Simultaneous measurements of Q ̇ derived from echocardiography [criterion] and Modelflow® were obtained at rest and during low-moderate intensity (25% and 50% peak power output) cycling exercise and compared using Bland-Altman analysis and limits of agreement. Agreement between echocardiography and Modelflow® was poor in non-pregnant, pregnant and postpartum women at rest (mean difference ± SD: -1.1 ± 3.4; -1.2 ± 2.9; -1.9 ± 3.2 L.min-1), and this remained evident during exercise. The Modelflow® method is not recommended for Q ̇ determination in research involving young, healthy non-pregnant and pregnant women at rest or during dynamic challenge. Previously published Q ̇ data from studies utilising this method should be interpreted with caution.




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How to Cite

Meah, V. L., Backx, K., Shave, R. E., Stöhr, E. J., & Cooper, S.-M. (2022). Comparison between Modelflow® and echocardiography in the determination of cardiac output during and following pregnancy at rest and during exercise. Journal of Human Sport and Exercise, 17(1), 116–135.



Sport Medicine, Nutrition & Health