ten Tusscher–Panfilov 2006 finitewave model

Implements the ten Tusscher–Panfilov 2006 (TP06) human ventricular ionic model.

The TP06 model is a detailed biophysical model of the human ventricular action potential, designed to simulate realistic electrical behavior in tissue including alternans, reentrant waves, and spiral wave breakup.

This model implementation can be used separately from the Finitewave, allowing for standalone simulations and testing of the model dynamics without the need for the entire framework.

Reference

ten Tusscher KH, Panfilov AV. Alternans and spiral breakup in a human ventricular tissue model. Am J Physiol Heart Circ Physiol. 2006 Sep;291(3):H1088–H1100.

DOI: 10.1152/ajpheart.00109.2006

How to use (quickstart)

python -m examples.ten_tusscher_panfilov_2006_example

How to test

python -m pytest -q

Repository structure

.
├── ten_tusscher_panfilov_2006/                # equations package (ops.py)
│   ├── __init__.py
│   └── ops.py                                 # model equations (pure functions)
├── implementation/                            # 0D model implementation
│   ├── __init__.py
│   └── ten_tusscher_panfilov_2006_0d.py
├── example/
│   └── ten_tusscher_panfilov_2006_example.py  # minimal script to run a short trace
├── tests/
│   └── test.py                                # smoke test; reproducibility checks
├── .gitignore
├── LICENSE                                    # MIT
├── pyproject.toml                             # configuration file
└── README.md                                  # this file

Variables

• u = -84.5 - Membrane potential (mV)
• cai = 0.00007 - Intracellular calcium concentration (mM)
• casr = 1.3 - SR calcium concentration (mM)
• cass = 0.00007 - Subspace calcium concentration (mM)
• nai = 7.67 - Intracellular sodium concentration (mM)
• Ki = 138.3 - Intracellular potassium concentration (mM)
• m = 0.0 - Sodium activation gate
• h = 0.75 - Sodium inactivation gate
• j = 0.75 - Sodium inactivation gate
• xr1 = 0.0 - Rapid delayed rectifier potassium activation gate
• xr2 = 1.0 - Rapid delayed rectifier potassium activation gate
• xs = 0.0 - Slow delayed rectifier potassium activation gate
• r = 0.0 - Transient outward potassium activation gate
• s = 1.0 - Transient outward potassium inactivation gate
• d = 0.0 - L-type calcium channel activation gate
• f = 1.0 - L-type calcium channel inactivation gate
• f2 = 1.0 - L-type calcium channel inactivation gate
• fcass = 1.0 - Calcium release inactivation gate
• rr = 1.0 - Ryanodine receptor activation gate
• oo = 0.0 - Ryanodine receptor open probability

Parameters

• ko = 5.4 - Potassium extracellular concentration

• cao = 2.0 - Calcium extracellular concentration

• nao = 140.0 - Sodium extracellular concentration

• Vc = 0.016404 - Cytoplasmic volume (in uL)

• Vsr = 0.001094 - Sarcoplasmic reticulum volume

• Vss = 0.00005468 - Subsarcolemmal space volume

• Bufc = 0.2 - Cytoplasmic buffer concentration

• Kbufc = 0.001 - Cai half-saturation constant for cytoplasmic buffer

• Bufsr = 10.0 - SR buffer concentration

• Kbufsr = 0.3 - CaSR half-saturation constant for sarcoplasmic buffer

• Bufss = 0.4 - Subsarcolemmal buffer concentration

• Kbufss = 0.00025 - CaSS half-saturation constant for subspace buffer

• Vmaxup = 0.006375 - Maximal calcium uptake rate

• Kup = 0.00025 - Calcium uptake affinity

• Vrel = 0.102 - Calcium release rate from SR

• k1_ = 0.15 - Transition rate for SR calcium release

• k2_ = 0.045 - Transition rate for SR calcium release

• k3 = 0.060 - Transition rate for SR calcium release

• k4_ = 0.005 - Alternative transition rate

• EC = 1.5 - Calcium-induced calcium release sensitivity

• maxsr = 2.5 - Maximum value of kcasr

• minsr = 1.0 - Minimum value of kcasr

• Vleak = 0.00036 - SR calcium leak rate

• Vxfer = 0.0038 - Calcium transfer rate from subspace to cytosol

• R = 8314.472 - Universal gas constant (J/(kmol·K))

• F = 96485.3415 - Faraday constant (C/mol)

• T = 310.0 - Temperature (Kelvin, 37°C)

• RTONF = 26.71376 - RT/F constant for Nernst equation

• CAPACITANCE = 0.185 - Membrane capacitance (μF/cm²)

• gkr = 0.153 - Rapid delayed rectifier K+ conductance

• gks = 0.392 - Slow delayed rectifier K+ conductance

• gk1 = 5.405 - Inward rectifier K+ conductance

• gto = 0.294 - Transient outward K+ conductance

• gna = 14.838 - Fast Na+ conductance

• gbna = 0.00029 - Background Na+ conductance

• gcal = 0.00003980 - L-type Ca2+ channel conductance

• gbca = 0.000592 - Background Ca2+ conductance

• gpca = 0.1238 - Sarcolemmal Ca2+ pump current conductance

• KpCa = 0.0005 - Sarcolemmal Ca2+ pump affinity

• gpk = 0.0146 - Na+/K+ pump current conductance

• pKNa = 0.03 - Na+/K+ permeability ratio

• KmK = 1.0 - Half-saturation for K+ activation

• KmNa = 40.0 - Half-saturation for Na+ activation

• knak = 2.724 - Maximal Na+/K+ pump rate

• knaca = 1000 - Maximal Na+/Ca2+ exchanger current

• KmNai = 87.5 - Half-saturation for Na+ binding

• KmCa = 1.38 - Half-saturation for Ca2+ binding

• ksat = 0.1 - Saturation factor

• n_ = 0.35 - Exponent for Na+ dependence