Non‐invasive cardiovascular profiling using combined electrocardiogram– D oppler ultrasonography and impedance cardiography: An experimental approach

In the present study, the feasibility of cardiovascular profiling using both combined electrocardiogram (ECG)-Doppler ultrasonography and impedance cardiography (ICG) was evaluated. Fourteen non-pregnant healthy women received 500 mL saline solution (NaCl 0.9% at 999 mL/h) intravenously by steady state infusion. Before and after this acute volume loading, we measured orthostatic-challenged cardiac and arterial characteristics using ICG and assessed venous characteristics by combined ECG-Doppler before and during the Valsalva manoeuvre. Changes are expressed as the mean ± SEM and were evaluated by the one-sample Wilcoxon signed-rank test. After volume loading, the observed fall in stroke volume after postural change from supine to standing decreased (-14 ± 3 vs -23 ± 2%; P = 0.011). Hepatic A wave velocity increased 63 ± 28% after volume loading (P = 0.007) and decreased during the Valsalva manoeuvre (-205 ± 21%; P = 0.001). Volume loading raised the thoracic fluid content index in both the supine and standing positions (7 ± 2% and 10 ± 1%, respectively; P ≤ 0.014). Combined ECG-Doppler ultrasonography and ICG enables the non-invasive identification of concomitant haemodynamic changes at the level of the heart, the arterial bed and the venous compartment. Our data support the view that non-invasive cardiovascular profiling is feasible, which seems particularly useful for the evaluation of patients who are not critically ill, such as pregnant women.