Experimental investigation of the effect of non-Newtonian behavior of blood flow in the Fontan circulation

Cheng, Andrew L.; Pahlevan, Niema M.; Rinderknecht, Derek; Wood, John C.; Gharib, Morteza

doi:10.1016/j.euromechflu.2017.12.009

Cited by 21 publications

(7 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In these settings, wall shear stress and areas of increased thrombotic potential may be characterized inaccurately when using a Newtonian fluid assumption. Expanding upon our prior clinical and experimental observations (10,11), we similarly demonstrate in the present study that non-Newtonian behavior affects power loss, pulmonary flow distribution, caval flow mixing, and shear stress in patient-derived synthetic models of the low-shear Fontan circulation. Since each of these factors can affect the long-term sequelae of the Fontan circulation, accurate measurements that incorporate non-Newtonian behavior (i.e., using 4D flow MRI in conjunction with computational fluid dynamic modeling) are necessary to properly risk stratify these patients.…”

Section: Discussionsupporting

confidence: 80%

“…We previously demonstrated that non-Newtonian behavior negatively impacts pulmonary blood flow in children with Glenn and Fontan circulations (11) and alters power loss, flows, and wall shear stress in a simplified synthetic model of the Fontan circulation (10). Expanding upon these observations, the goal of this study was to use four-dimensional (4D) flow magnetic resonance imaging (MRI) to evaluate how realistic non-Newtonian viscosity affects flow in patient-specific experimental models of the Fontan circulation.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A 4D flow MRI evaluation of the impact of shear-dependent fluid viscosity on in vitro Fontan circulation flow

Cheng

Wee

Pahlevan

et al. 2019

American Journal of Physiology-Heart and Circulatory Physiology

Self Cite

View full text Add to dashboard Cite

The Fontan procedure for univentricular heart defects creates a nonphysiologic circulation where systemic venous blood drains directly into the pulmonary arteries, leading to multiorgan dysfunction secondary to chronic low-shear nonpulsatile pulmonary blood flow and central venous hypertension. Although blood viscosity increases exponentially in this low-shear environment, the role of shear-dependent (“non-Newtonian”) blood viscosity in this pathophysiology is unclear. We studied three-dimensional (3D)-printed Fontan models in an in vitro flow loop with a Philips 3-T magnetic resonance imaging (MRI) scanner. A 4D flow phase-contrast sequence was used to acquire a time-varying 3D velocity field for each experimental condition. On the basis of blood viscosity of a cohort of patients who had undergone the Fontan procedure, it was decided to use 0.04% xanthan gum as a non-Newtonian blood analog; 45% glycerol was used as a Newtonian control fluid. MRI data were analyzed using GTFlow and MATLAB software. The primary outcome, power loss, was significantly higher with the Newtonian fluid [14.8 (13.3, 16.4) vs. 8.1 (6.4, 9.8)%, medians with 95% confidence interval, P < 0.0001]. The Newtonian fluid also demonstrated marginally higher right pulmonary artery flow, marginally lower shear stress, and a trend toward higher caval flow mixing. Outcomes were modulated by Fontan model complexity, cardiac output, and caval flow ratio. Vortexes, helical flow, and stagnant flow were more prevalent with the non-Newtonian fluid. Our data demonstrate that shear-dependent viscosity significantly alters qualitative flow patterns, power loss, pulmonary flow distribution, shear stress, and caval flow mixing in synthetic models of the Fontan circulation. Potential clinical implications include effects on exercise capacity, ventilation-perfusion matching, risk of pulmonary arteriovenous malformations, and risk of thromboembolism. NEW & NOTEWORTHY Although blood viscosity increases exponentially in low-shear environments, the role of shear-dependent (“non-Newtonian”) blood viscosity in the pathophysiology of the low-shear Fontan circulation is unclear. We demonstrate that shear-dependent viscosity significantly alters qualitative flow patterns, power loss, pulmonary flow distribution, shear stress, and caval flow mixing in synthetic models of the Fontan circulation. Potential clinical implications include effects on exercise capacity, ventilation-perfusion matching, risk of pulmonary arteriovenous malformations, and risk of thromboembolism.

show abstract

Section: Discussionsupporting

confidence: 80%

Section: Introductionmentioning

confidence: 99%

A 4D flow MRI evaluation of the impact of shear-dependent fluid viscosity on in vitro Fontan circulation flow

Cheng

Wee

Pahlevan

et al. 2019

American Journal of Physiology-Heart and Circulatory Physiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…The measurement uncertainties regarding the pressure transducers and owmeters were approximately 2%. A non-Newtonian single-phase blood analog that has been reported to closely match the blood viscosity of Fontan patients [51,52] was prepared and used as the working uid.…”

Section: Pulsatile In Vitro Mock Circulatory Loopmentioning

confidence: 99%

In Vitro Hemodynamic Performance of a Blood Pump for Self-powered Venous Assist in Univentricular Hearts

Rasooli,

Holmstrom,

Giljarhus

et al. 2023

Preprint

View full text Add to dashboard Cite

Univentricular heart anomalies represent a group of severe congenital heart defects necessitating early surgical intervention in infancy. The Fontan procedure, the final stage of single-ventricle palliation, establishes a serial connection between systemic and pulmonary circulation by channeling venous return to the lungs. The absence of the subpulmonary ventricle in this peculiar circulation progressively eventuates in failure, primarily due to chronic elevation in inferior vena cava (IVC) pressure. This study experimentally validates the effectiveness of an intracorporeally-powered venous ejector pump (VEP) in reducing IVC pressure in Fontan patients. The VEP exploits a fraction of aortic flow to create a jet-venturi effect for the IVC, negating the external power requirement and driveline infections. A multi-scale in-vitro Fontan mock-up circulation loop is developed and the impact of VEP design parameters and physiological conditions is assessed using both idealized and patient-specific total cavopulmonary connection (TCPC) phantoms. The VEP performance in reducing IVC pressure exhibited an inverse relationship with the cardiac output and extra-cardiac conduit (ECC) size and a proportional relationship with the transpulmonary pressure gradient (TPG) and mean arterial pressure (MAP). The ideal VEP with fail-safe features provided an IVC pressure drop of 1.82 ± 0.49, 2.45 ± 0.54, and 3.12 ± 0.43 mm Hg for TPG values of 6, 8, and 10 mm Hg, respectively, averaged over all ECC sizes and cardiac outputs. Furthermore, the arterial oxygen saturation was consistently maintained above 85% in all conditions. These results emphasize the potential utility of the VEP to mitigate elevated venous pressure in Fontan patients.

show abstract

“…However, recent studies on simplified dilation geometries, such as is seen in the sinus, reveals the significant differences in WSS-related parameters seen with even small changes in the viscoelastic and shear-thinning behavior of blood ( Bilgi and Atalik, 2019 , 2020 ). Furthermore, experiments on Fontan hemodynamics highlight that neglecting non-Newtonian behavior like shear-thinning can produce significant errors and misinterpretation of the hemodynamics ( Cheng et al, 2018a , b , 2019 ; Wei H. et al, 2020 ; Wei Z. et al, 2020 ). These studies demonstrate the important role of shear-thinning relevant to specific clinical problems such as Fontan flows and aneurysms.…”

Section: The Unique Flow and Shear Stress Characteristics Of The Carotid Sinusmentioning

confidence: 99%

The Rheology of the Carotid Sinus: A Path Toward Bioinspired Intervention

Iskander

Bilgi

Naftalovich

et al. 2021

Front. Bioeng. Biotechnol.

View full text Add to dashboard Cite

The association between blood viscosity and pathological conditions involving a number of organ systems is well known. However, how the body measures and maintains appropriate blood viscosity is not well-described. The literature endorsing the function of the carotid sinus as a site of baroreception can be traced back to some of the earliest descriptions of digital pressure on the neck producing a drop in blood delivery to the brain. For the last 30 years, improved computational fluid dynamic (CFD) simulations of blood flow within the carotid sinus have demonstrated a more nuanced understanding of the changes in the region as it relates to changes in conventional metrics of cardiovascular function, including blood pressure. We suggest that the unique flow patterns within the carotid sinus may make it an ideal site to transduce flow data that can, in turn, enable real-time measurement of blood viscosity. The recent characterization of the PIEZO receptor family in the sinus vessel wall may provide a biological basis for this characterization. When coupled with other biomarkers of cardiovascular performance and descriptions of the blood rheology unique to the sinus region, this represents a novel venue for bioinspired design that may enable end-users to manipulate and optimize blood flow.

show abstract

Experimental investigation of the effect of non-Newtonian behavior of blood flow in the Fontan circulation

Cited by 21 publications

References 40 publications

A 4D flow MRI evaluation of the impact of shear-dependent fluid viscosity on in vitro Fontan circulation flow

A 4D flow MRI evaluation of the impact of shear-dependent fluid viscosity on in vitro Fontan circulation flow

In Vitro Hemodynamic Performance of a Blood Pump for Self-powered Venous Assist in Univentricular Hearts

The Rheology of the Carotid Sinus: A Path Toward Bioinspired Intervention

Contact Info

Product

Resources

About