Impedance Cardiographya

Salt induces oxidative stress in salt-sensitive (SS) animals and man. It is unknown in SS subjects if the low-sodium Dietary Approaches to Stop Hypertension (LS-DASH) reduces oxidative stress more than DASH, which is high in anti-oxidants. To assess the effects of DASH and LS-DASH on oxidative stress, 19 volunteers were studied after 3-weeks of a standardized usual low fruits and vegetables diet (ULFV), followed by 3-weeks on DASH (both diets ∼120 mmol Na+/day), then 3-weeks on low-sodium (LS)-DASH (60 mmol Na+/d). SS was defined as systolic blood pressure ≥5 mmHg lower on LS-DASH than DASH. In SS subjects (N=9), systolic blood pressure was lower on LS-DASH (111.0±2.0 mmHg) than DASH (118.0±2.2, p<0.01) and ULFV (122.3±2.7, p=0.002). In salt-resistant (SR) volunteers (N=10), systolic blood pressure was lower on DASH (113.0±1.6) than ULFV (119.0±1.8, p<0.05) but not LS-DASH (115.7±1.8). Urine F2-isoprostanes, a marker of oxidative stress, were lower in SS subjects on LS-DASH (1.69±0.24) than ULFV (3.09±0.50, p<0.05) and marginally lower than DASH (2.46±0.44, p<0.20). F2-isoprostanes were not different among the three diets in SR volunteers (2.18±0.29, 2.06±0.29, 2.27±0.53, respectively). Aortic augmentation index, a measure of vascular stiffness, was lower in SS subjects on LS-DASH than either DASH or ULFV, and lower on DASH than ULFV in SR volunteers. In SS but not SR subjects, LS-DASH is associated with lower values for F2-isorprostane and the aortic augmentation index. The results suggest that LS-DASH decreases oxidative stress, improves vascular function and lowers blood pressure in SS but not SR volunteers.

show abstract

“…Cardiac output, thoracic fluid content, and heart rate were measured by BioZ impedance cardiography (CardioDynamics, San Diego, CA). 23…”

Section: Methodsmentioning

confidence: 99%

Low-sodium DASH reduces oxidative stress and improves vascular function in salt-sensitive humans

et al. 2009

View full text Add to dashboard Cite

show abstract

“…In a study published in 2000, the difference in CO levels obtained by IPc and TD was 0.31 L/min and the coefficient of correlation was 0.72 ( p < 0.001) [22]. In another study published in 2003 [23], the correlation was good ( r 2 = 0.658, p < 0.001). In the study conducted by Yung and al.…”

Section: Discussionmentioning

confidence: 99%

Determination of Cardiac Output in Pulmonary Hypertension Using Impedance Cardiography

et al. 2018

View full text Add to dashboard Cite

Background: Cardiac output (CO) is a prognostic factor in pulmonary hypertension (PH). Right heart catheterisation using the direct Fick method or thermodilution (TD) is the reference technique for CO measurement. Impedance cardiography (IPc) is a known non-invasive method of measuring CO. Objectives: In our study, we assume that the measurement of CO by IPc using the PHYSIOFLOW® system is as accurate as TD or using the direct Fick method in patients with PH in group 1 or group 4. Methods: A total of 75 patients were enrolled in a prospective study carried out at the hypertension reference centre of Toulouse University Hospital. Right heart catheterisation was performed for the diagnosis or follow-up of the disease. CO was measured using the Fick method, TD, and IPc simultaneously. A Bland-Altman analysis was plotted. Results: CO was 5.7 ± 1.9 L/min as measured by the Fick method, 5.4 ± 1.5 L/min by TD, and 5.5 ± 1.7 L/min by IPc. The bias between CO measurements by IPc and the direct Fick method was 0.149 L/min (95% CI, –0.298 to 0.596). The bias between CO measurements by IPc and the TD method was –0.153 L/min (95% CI, –0.450 to 0.153). The correlation decreased with the more extreme CO values (< 3 L/min or > 7 L/min). A few factors changed the agreement between measurements (BMI or membership in group 4). Conclusion: To conclude, this study shows that the measurement of CO by IPc in PH patients is reliable compared to the direct Fick method and TD obtained by right heart catheterisation. This accuracy decreases for extreme CO values.

show abstract

“…To date little data exist on ICG use in pregnancy since the recently updated ICG software was updated in 1998. [19] What does exist is either retrospective, has only a single time point, or lacks comparison with other cardiovascular assessments such as thermography or echo. Moreover, there are little comparative data on maternal hemodynamic parameters during labor using ICG and echo.…”

Section: Discussionmentioning

confidence: 99%

“…Indirect, or derived, measures of systolic function include the systolic time ratio (STR) defined as the pre-ejection period (PEP) or electrical systole divided by the left ventricular ejection time (LVET) or mechanical systole; and acceleration index (ACI) [19]. .…”

Section: Introductionmentioning

confidence: 99%

Noninvasive cardiac monitoring in pregnancy: impedance cardiography versus echocardiography

et al. 2013

View full text Add to dashboard Cite

Objectives The objective of this study was to report thoracic impedance cardiography (ICG) measurements and compare them to echocardiography (echo) measurements throughout pregnancy and in varied maternal positions. Methods A prospective cohort study involving 28 healthy parturients was performed using ICG and echo at three time points and in two maternal positions. Pearson correlations, Bland-Altman plots and paired t-tests were used for statistical analysis. Results Significant agreements between many but not all ICG and echo contractility, flow and resistance measurements were demonstrated. Differences in stroke volume due to maternal position were also detected by ICG in the antepartum period. Significant trends were observed by ICG for cardiac output and thoracic fluid content (TFC) (p < 0.025) with advancing pregnancy stages. Conclusions ICG and echo demonstrate significant correlations in some but not all measurements of cardiac function. ICG has the ability to detect small changes in SV associated with maternal position change. ICG measurements reflected maximal cardiac contractility in the antepartum period yet reflected a decrease in contractility and an increase in TFC in the postpartum period.

show abstract

Impedance Cardiographya

Cited by 190 publications

References 15 publications

Low-sodium DASH reduces oxidative stress and improves vascular function in salt-sensitive humans

Low-sodium DASH reduces oxidative stress and improves vascular function in salt-sensitive humans

Determination of Cardiac Output in Pulmonary Hypertension Using Impedance Cardiography

Noninvasive cardiac monitoring in pregnancy: impedance cardiography versus echocardiography

Contact Info

Product

Resources

About