One-point carotid wave intensity predicts cardiac mortality in patients with congestive heart failure and reduced ejection fraction

Abstract

Wave intensity (WI) is a hemodynamic index used to evaluate the interaction between the heart and the arterial system, measured with an echo-Doppler system at the level of the common carotid artery. WI has two peaks: W1 during early systole that represents left ventricular (LV) contractility, and W2 in late systole that is related to the inertia force during isovolumetric relaxation. The aim of this study was to determine whether WI parameters improve the prediction of poor outcome in patients with heart failure and reduced ejection fraction (HFrEF). Sixty-two patients (mean age 69.4 ± 11.5 years) in NYHA class II-III were followed up for 43.5 months. They underwent routine clinical work-up, transthoracic echocardiography and WI measurement. A stratified survival analysis was conducted using the Kaplan-Meier method. During follow-up, 23 patients died from cardiovascular causes. Survivors and non-survivors were similar in age, blood pressure, heart rate and echocardiographic parameters, except for LV end-diastolic volume indexed to body surface area, E/A ratio (higher in non-survivors) and deceleration time (lower in non-survivors). W2 (1950 ± 1006 vs 1117 ± 708 mmHg m/s(3), p = 0.001) was significantly lower in non-survivors, whereas W1 (6951 ± 4119 vs 5748 ± 3891 mmHg m/s(3), p = NS) was similar. At the end of follow-up, cardiovascular mortality was higher in patients with W1 ≤ 3900 mmHg m/s(3) (p = 0.02) and W2 ≤ 1000 mmHg m/s(3) (p = 0.0002). Only E/A (cut-off 1.5) was predictive of mortality (p = 0.05). In patients with HFrEF, WI parameters derived from the carotid artery better identified patients with poor prognosis and were significant predictors of cardiovascular mortality.

Comparison of arterial wave intensity analysis by pressure–velocity and diameter–velocity methods in a virtual population of adult subjects

“…The increase in arterial diameter with increasing age causes a decrease in both viscoelasticity and strain-stiffening as modelled by equations (5), (6) and (10). Hence, the older the subject, the smaller the differences Figure 8.…”

“…As a result of these variations, the stiffness parameter b and the viscoelastic parameter G calculated through equations (6) and 7were changed through a combination of the formula for estimating wall thickness and the multipliers for diameter, PWV and wall viscosity.…”

“…Analysis of wave intensity (WI) 1 is clinically useful, as arterial waves carry information about the performance of the heart and blood vessels, [2][3][4][5][6] but its utility is restricted by its reliance upon measurements of blood pressure with high temporal resolution, which can only be measured invasively or estimated inaccurately from noninvasive methods. To obviate this restriction, Feng and Khir 7 introduced a new formulation of WI that instead relies only upon diameter and velocity; both can be obtained from spatiotemporally coincident ultrasound images, but there is a lack of research on the efficacy of this noninvasive formulation as a surrogate for conventional WI.…”

Clinical usefulness of cardio-ankle vascular index, local artery carotid stiffness and global longitudinal strain in subjects with cardiovascular risk factors

“…[4] For all these reasons, efforts are increasingly being targeted toward early diagnosis for intervening at an earlier stage of disease. Italian Society of Echocardiography has been involved from its origins in preventive field, developing several research programs,[4567891011121314] including Disfunzione Asintomatica VEntricolare Sinistra[15] study (on cardiac field), and considering deeply prognostic implications of vascular disease.…”

Wave Intensity Analysis Combined With Machine Learning can Detect Impaired Stroke Volume in Simulations of Heart Failure

“…Arterial pulse waves carry information about the performance of the heart and vessels, and several studies have identified statistically significant changes in the metrics derived from wave intensity (WI) in the presence of impaired heart performance (Curtis et al, 2007;Siniawski et al, 2009;Li and Guo, 2013;Takaya et al, 2013;Vriz et al, 2015) but only when averaged over groups. Furthermore, WI has generally been determined from measurements of blood velocity and pressure made throughout the cardiac cycle (Parker, 2009), but pressure waveforms with sufficient temporal resolution can only be obtained accurately by invasive methods or estimated inaccurately by noninvasive ones, which has inhibited the clinical realisability of WI-based diagnostic methods.…”