Nektar1D is our in-house code for solving the nonlinear, one-dimensional (1-D) equations of
blood flow in a given network of compliant vessels subject to boundary and initial conditions. To request all the files needed to compile Nektar1D on your computer, together with examples of 1-D model simulations used in our articles, please drop an email to
jordi.alastruey-arimon@kcl.ac.uk.
You can download a
reference manual for Nektar1D describing how to compile the code, create and run your own simulations, and interpret the results from
here.
For a
review on arterial pulse wave haemodynamics and a description of the 1-D equations and the numerical scheme used to solve them in Nektar1D, we refer to the following publications:
Jordi Alastruey, Peter H. Charlton, et al.
Arterial pulse wave modelling and analysis for vascular age studies: a review from VascAgeNet.
Am. J. Physiol. Heart Circ. Physiol.,
325(1):H1-H29, 2023.
Jordi Alastruey, Kim H. Parker, and Spencer J. Sherwin.
Arterial pulse wave haemodynamics.
In Anderson S (Ed.), 11th International Conference on Pressure Surges,
Virtual PiE Led t/a BHR Group,
Chapter 7, 401–442, 2012.
Several
tools for analysing the simulated pressure and flow waveforms are described in the following articles:
Marie Willemet and Jordi Alastruey.
Arterial pressure and flow wave analysis using time-domain 1-D hemodynamics.
Ann. Biomed. Eng.
43(1), 190–206, 2014.
PH Charlton, P Celka, B Farukh, P Chowienczyk, and J Alastruey.
Assessing mental stress from the photoplethysmogram: a numerical study.
Physiological Measurement
39(5), 054001, 2018.
1-D modelling provides a good balance between accuracy and computational cost, as we have demonstrated by comparison against
(i) experimental data in a 1:1 scale cardiovascular simulator rig of the aorta and its larger branches made of silicone tubes (J Biomech,
2011 &
2007),
(ii)
in vivo data in humans (
Heliyon, 2024;
J Royal Soc Interface, 2016), rabbits (
J. Biomech, 2009)
and
(iii) numerical data obtained by solving the full 3-D equations of blood flow in compliant vessels (J Royal Soc Interface,
2021 &
2016;
Ann Biomed Eng, 2016; Int J Numer Meth Biomed Engng,
2015 &
2014).
We have used Nektar1D to create
populations of thousands of virtual subjects for
in silico evaluation of pulse wave indices and algorithms (
Symmetry, 2021; Am J Physiol,
2015 and
2019;
J Biomech, 2016). Nektar1D has also been used in the
clinically relevant studies described here.
Nektar1D has recently been
coupled to a 3-D cardiac electromechanics model that allows us to study the effects of pulse wave propagation on cardiac function (
Comput Mech, 2022).