Hemodynamic differences among hypertensive patients with and without heart failure using impedance cardiography

Abstract

Background:Impedance cardiography is a reliable, well-tolerated, and non-invasive method used to obtain hemodynamic measurements and could potentially be useful in heart failure (HF) diagnosis, hemodynamic monitoring of critically ill patients, and help in the choice of antihypertensive therapy. The objective of this study was to determine the differences between hemodynamic parameters in a study population of hypertensive patients with and without HF, using impedance cardiography.Methods:A case-control study was designed and named the TARGET study. Participants were enrolled in two study groups: control group C, hypertensive patients without HF and the HF group, hypertensive patients with HF. A descriptive analysis was carried out to characterize the sample and differences in continuous variables were tested for statistical significance by independent sample t test.Results:The study included 102 hypertensive outpatients. The control group consisted of 77 individuals (58.4% males; mean age 63.9 ± 12.5 years old) and the HF group consisted of 25 individuals (44.0% males; mean age 74.2 ± 8.7 years old). The mean Cardiac Index (CI) was 2.70 ± 1.02 L.min.m−2(2.89 ± 1.04 versus 2.12 ± 0.70; p < 0.001), mean Stroke Index (SI) was 35.5 ± 14.7 mL.m−2(37.7 ± 15.2 versus 28.5 ± 10.8; p = 0.006), mean Ejection Phase Contractility Index (EPCI) was 33.7 ± 12.7 1000 s−2(35.8 ± 13.1 versus 27.2 ± 9.2; p = 0.003), mean Inotropic State Index (ISI) was 74.3 ± 28.2 100 s−2(78.8 ± 28.9 versus 60.6 ± 20.7; p = 0.005), and mean Left Stroke Work Index (LSWI) was 51.3 ± 23.1 g.min.m−2(55.4 ± 23.5 versus 38.9 ± 16.6; p = 0.002).Conclusions:In this study, hypertensive patients with HF had significantly lower values of blood flow parameters, contractility, and left work indices compared with hypertensive patients without HF. These differences reflected the incorrect hemodynamic pattern (mostly hypodynamic) of these patients. Impedance cardiography (ICG) seems to be an adequate method to reflect these differences.

Validation of a new impedance cardiography analysis algorithm for clinical classification of stress states

“…Our findings have important potential clinical applications and public health implications, which call for more research in this area. Accurate PEP examination with TEA may improve prediction of mortality in the general population (Medina‐Lezama et al, 2018), evaluation of early cardiovascular disease, management of hypertension (DeMarzo, 2020; Silva Lopes et al, 2019), and for assessing stress levels in persons with PTSD and monitoring autonomic function (Czarnek et al, 2021; Kelsey et al, 2007; Kibler, 2018; Malcolm et al, 2016; Meijer et al, 2011; Silvia et al, 2020).…”

Impedance cardiogram based exploration of cardiac mechanisms in post‐traumatic stress disorder during trauma recall

“…• Velocity index (VI): VI, also known as systolic amplitude, ejection phase contractility index, and index of contractility, is a variable proportional to blood flow in the aorta, indicating maximum myocardial contractility during systole (DeMarzo, 2020;Silva Lopes et al, 2019). It was computed via the synchronized EA ICG beat as 1000.…”

“…It was computed via the synchronized EA ICG beat as 1000. (−dZ/dt) max •Z 0 −1 , [0.001.s −1 ], where Z 0 was the time average of the EA Z(t) beat, and (−dZ/dt) max was the maximum amplitude of EA −dZ/dt beat (Peng et al, 2004;Silva Lopes et al, 2019).…”

Cardiovascular diseases diagnosis by impedance cardiography

“…In [ 50 ], hypertensive patients with heart failure (HF) had significantly lower values of blood flow parameters, contractility, and left work indices compared with hypertensive patients without HF. These differences reflected the incorrect hemodynamic pattern (mostly hypodynamic) of these patients.…”