NhsContractionModel Class Reference

#include <NhsContractionModel.hpp>

Inheritance diagram for NhsContractionModel:

Collaboration diagram for NhsContractionModel:

List of all members.

Public Member Functions

NhsContractionModel ()

void SetStretchAndStretchRate (double lambda, double dlambdaDt)

void SetInputParameters (ContractionModelInputParameters &rInputParameters)

void SetIntracellularCalciumConcentration (double calciumConcentration)

double GetCalciumTroponinValue ()

void EvaluateYDerivatives (double time, const std::vector< double > &rY, std::vector< double > &rDY)

double GetActiveTension ()

double GetNextActiveTension ()

bool IsStretchDependent ()

bool IsStretchRateDependent ()

Protected Member Functions

void CalculateCalciumTrop50 ()

double CalculateT0 (double z)

Protected Attributes

double mLambda

double mDLambdaDt

double mCalciumI

double mCalciumTrop50

double mK1

double mK2

Static Protected Attributes

static const double mKon = 100

static const double mKrefoff = 0.2

static const double mGamma = 2

static const double mCalciumTroponinMax = 0.07

static const double mAlphaR1 = 0.002

static const double mAlphaR2 = 0.0017

static const double mKZ = 0.15

static const unsigned mNr = 3u

static const double mBeta1 = -4

static const double mAlpha0 = 0.008

static const unsigned mN = 3u

static const double mZp = 0.85

static const double mCalcium50ref = 0.00105

static const double mTref = 56.2

static const double mBeta0 = 4.9

static const double mA = 0.35

static const double mA1 = -29

static const double mA2 = 138

static const double mA3 = 129

static const double mAlpha1 = 0.03

static const double mAlpha2 = 0.130

static const double mAlpha3 = 0.625

Friends

class TestContractionModels

Detailed Description

NHS (Niederer, Hunter, Smith) model of active tension in cardiac cells.

A system of ODEs which determines the active potential, given the intracellular calcium concentration, the stretch (lambda) of the cell, and the stretch rate (dlambda_dt) of the cell.

The state variables are, in order: Calcium_troponin, z, Q1, Q2, Q3

Reference: S.A. Niederer, N.P. Smith, P.J. Hunter, "New developments in a strongly coupled cardiac electro-mechanical model" Europace 7, S118-S127

The active tension is returned in KPa.

Definition at line 49 of file NhsContractionModel.hpp.

Constructor & Destructor Documentation

NhsContractionModel::NhsContractionModel ( )

Constructor. Initialises all state variables to zero, lambda to 1, dlambda_dt to 0 and intracellular calcium concentration to 0

Definition at line 93 of file NhsContractionModel.cpp.

References CalculateCalciumTrop50(), OdeSystemInformation< ODE_SYSTEM >::Instance(), mAlphaR2, mCalciumI, mDLambdaDt, mK1, mK2, mKZ, mLambda, mNr, AbstractParameterisedSystem< std::vector< double > >::mpSystemInfo, mZp, and AbstractParameterisedSystem< std::vector< double > >::ResetToInitialConditions().

Member Function Documentation

void NhsContractionModel::CalculateCalciumTrop50 ( ) [protected]

Compute the calcium_trop50 concentration. This is a function of constants and lambda, so only needs to be called in the constructor or when lambda is set

Definition at line 67 of file NhsContractionModel.cpp.

References mBeta0, mBeta1, mCalcium50ref, mCalciumTrop50, mCalciumTroponinMax, mGamma, mKon, mKrefoff, and mLambda.

Referenced by NhsContractionModel(), and SetStretchAndStretchRate().

double NhsContractionModel::CalculateT0 ( double z ) [protected]

Calculate T0. This is a function of constants, lambda and z

Parameters:

z

Definition at line 77 of file NhsContractionModel.cpp.

References mAlpha0, mAlphaR1, mBeta0, mCalciumTrop50, mCalciumTroponinMax, mK1, mK2, mLambda, mN, and mTref.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), EvaluateYDerivatives(), GetActiveTension(), and NhsModelWithBackwardSolver::GetNextActiveTension().

void NhsContractionModel::SetStretchAndStretchRate	(	double	lambda,
		double	dlambdaDt
	)			`[virtual]`

Set the current stretch and the stretch rate of the cell/fibre

Parameters:

	lambda	current stretch
	dlambdaDt	current stretch rate

Implements AbstractContractionModel.

Definition at line 115 of file NhsContractionModel.cpp.

References CalculateCalciumTrop50(), mDLambdaDt, and mLambda.

void NhsContractionModel::SetInputParameters ( ContractionModelInputParameters & rInputParameters ) [virtual]

Set the current intracellular calcium concentration

Parameters:

rInputParameters

input parameters (calcium, voltage, time, of which only calcium is used)

Implements AbstractContractionModel.

Definition at line 124 of file NhsContractionModel.cpp.

References DOUBLE_UNSET, ContractionModelInputParameters_::intracellularCalciumConcentration, and mCalciumI.

void NhsContractionModel::SetIntracellularCalciumConcentration ( double calciumConcentration )

Directly set the intracellular calcium concentration.

Parameters:

calciumConcentration

calcium concentration.

Definition at line 131 of file NhsContractionModel.cpp.

References mCalciumI.

double NhsContractionModel::GetCalciumTroponinValue ( )

Get the current Calcium Troponin (one of the state variables) value. This may be needed if the cell model has Calcium troponin and might need overwriting

Definition at line 137 of file NhsContractionModel.cpp.

References AbstractParameterisedSystem< std::vector< double > >::mStateVariables.

void NhsContractionModel::EvaluateYDerivatives	(	double	time,
		const std::vector< double > &	rY,
		std::vector< double > &	rDY
	)			`[virtual]`

Evaluate the derivatives of the state variables

Parameters:

	time	the current time, in milliseconds
	rY	current values of the state variables
	rDY	to be filled in with derivatives

Implements AbstractOdeSystem.

Definition at line 142 of file NhsContractionModel.cpp.

References CalculateT0(), EXCEPTION, mA, mA1, mA2, mA3, mAlpha0, mAlpha1, mAlpha2, mAlpha3, mAlphaR1, mAlphaR2, mCalciumI, mCalciumTrop50, mCalciumTroponinMax, mDLambdaDt, mGamma, mKon, mKrefoff, mKZ, mN, mNr, and mTref.

double NhsContractionModel::GetActiveTension ( ) [virtual]

Get the active tension, which is a function of the constants and current state variables. KILOPASCALS

Implements AbstractContractionModel.

Definition at line 200 of file NhsContractionModel.cpp.

References CalculateT0(), mA, and AbstractParameterisedSystem< std::vector< double > >::mStateVariables.

double NhsContractionModel::GetNextActiveTension ( ) [inline, virtual]

GetNextActiveTension() normally returns the active tension corresponding to the state variables that have been computed in RunDoNotUpdate. However, this only applies to when an implicit cardiac mechanics solver is used, in which case the NhsModelWithBackwardSolver should be used.

Implements AbstractContractionModel.

Reimplemented in NhsModelWithBackwardSolver.

Definition at line 204 of file NhsContractionModel.hpp.

References EXCEPTION.

bool NhsContractionModel::IsStretchDependent ( ) [inline, virtual]

This model is stretch-dependent

Implements AbstractContractionModel.

Definition at line 212 of file NhsContractionModel.hpp.

bool NhsContractionModel::IsStretchRateDependent ( ) [inline, virtual]

This model is stretch-rate-dependent

Implements AbstractContractionModel.

Definition at line 220 of file NhsContractionModel.hpp.

Member Data Documentation

double NhsContractionModel::mLambda [protected]

The stretch. To be specified by the caller

Definition at line 55 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50(), CalculateT0(), NhsContractionModel(), and SetStretchAndStretchRate().

double NhsContractionModel::mDLambdaDt [protected]

The stretch rate. To be specified by the caller

Definition at line 57 of file NhsContractionModel.hpp.

Referenced by EvaluateYDerivatives(), NhsModelWithBackwardSolver::ImplicitSolveForQ(), NhsContractionModel(), and SetStretchAndStretchRate().

double NhsContractionModel::mCalciumI [protected]

The intracellular calcium concentration. To be specified by the caller

Definition at line 59 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), EvaluateYDerivatives(), NhsContractionModel(), SetInputParameters(), and SetIntracellularCalciumConcentration().

double NhsContractionModel::mCalciumTrop50 [protected]

A parameter only dependent on constants and lambda, so updated whenever lambda is updated

Definition at line 63 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50(), NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), CalculateT0(), and EvaluateYDerivatives().

double NhsContractionModel::mK1 [protected]

A constant determined from the other constrants. Set up in the constructor

Definition at line 66 of file NhsContractionModel.hpp.

Referenced by CalculateT0(), and NhsContractionModel().

double NhsContractionModel::mK2 [protected]

A constant determined from the other constrants. Set up in the constructor

Definition at line 68 of file NhsContractionModel.hpp.

Referenced by CalculateT0(), and NhsContractionModel().

const double NhsContractionModel::mKon = 100 [static, protected]

See reference. (mMols)^-1 (ms)^-1

Definition at line 73 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50(), NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), and EvaluateYDerivatives().

const double NhsContractionModel::mKrefoff = 0.2 [static, protected]

See reference. (ms)^-1

Definition at line 76 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50(), NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), and EvaluateYDerivatives().

const double NhsContractionModel::mGamma = 2 [static, protected]

See reference. Dimensionless

Definition at line 79 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50(), NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), and EvaluateYDerivatives().

const double NhsContractionModel::mCalciumTroponinMax = 0.07 [static, protected]

See reference. mMols

Definition at line 82 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50(), NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), CalculateT0(), and EvaluateYDerivatives().

const double NhsContractionModel::mAlphaR1 = 0.002 [static, protected]

See reference. (ms)^-1

Definition at line 85 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), CalculateT0(), and EvaluateYDerivatives().

const double NhsContractionModel::mAlphaR2 = 0.0017 [static, protected]

See reference. (ms)^-1

Definition at line 88 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), EvaluateYDerivatives(), and NhsContractionModel().

const double NhsContractionModel::mKZ = 0.15 [static, protected]

See reference. Dimensionless

Definition at line 91 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), EvaluateYDerivatives(), and NhsContractionModel().

const unsigned NhsContractionModel::mNr = 3u [static, protected]

See reference. Dimensionless

Definition at line 94 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), EvaluateYDerivatives(), and NhsContractionModel().

const double NhsContractionModel::mBeta1 = -4 [static, protected]

See reference. Dimensionless

Definition at line 97 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50().

const double NhsContractionModel::mAlpha0 = 0.008 [static, protected]

See reference. (ms)^-1

Definition at line 100 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), CalculateT0(), and EvaluateYDerivatives().

const unsigned NhsContractionModel::mN = 3u [static, protected]

See reference. Dimensionless

Definition at line 103 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), CalculateT0(), and EvaluateYDerivatives().

const double NhsContractionModel::mZp = 0.85 [static, protected]

See reference. Dimensionless

Definition at line 106 of file NhsContractionModel.hpp.

Referenced by NhsContractionModel().

const double NhsContractionModel::mCalcium50ref = 0.00105 [static, protected]

See reference. mMols

Definition at line 109 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50().

const double NhsContractionModel::mTref = 56.2 [static, protected]

See reference. kPa

Definition at line 112 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), CalculateT0(), and EvaluateYDerivatives().

const double NhsContractionModel::mBeta0 = 4.9 [static, protected]

See reference. Dimensionless

Definition at line 115 of file NhsContractionModel.hpp.

Referenced by CalculateCalciumTrop50(), and CalculateT0().

const double NhsContractionModel::mA = 0.35 [static, protected]

See reference. Dimensionless

Definition at line 118 of file NhsContractionModel.hpp.

Referenced by NhsModelWithBackwardSolver::CalculateCaTropAndZDerivatives(), EvaluateYDerivatives(), GetActiveTension(), and NhsModelWithBackwardSolver::GetNextActiveTension().

const double NhsContractionModel::mA1 = -29 [static, protected]

See reference. Dimensionless

Definition at line 121 of file NhsContractionModel.hpp.

Referenced by EvaluateYDerivatives(), and NhsModelWithBackwardSolver::ImplicitSolveForQ().

const double NhsContractionModel::mA2 = 138 [static, protected]

See reference. Dimensionless

Definition at line 124 of file NhsContractionModel.hpp.

Referenced by EvaluateYDerivatives(), and NhsModelWithBackwardSolver::ImplicitSolveForQ().

const double NhsContractionModel::mA3 = 129 [static, protected]

See reference. Dimensionless

Definition at line 127 of file NhsContractionModel.hpp.

Referenced by EvaluateYDerivatives(), and NhsModelWithBackwardSolver::ImplicitSolveForQ().

const double NhsContractionModel::mAlpha1 = 0.03 [static, protected]

See reference. (ms)^-1

Definition at line 130 of file NhsContractionModel.hpp.

Referenced by EvaluateYDerivatives(), and NhsModelWithBackwardSolver::ImplicitSolveForQ().

const double NhsContractionModel::mAlpha2 = 0.130 [static, protected]

See reference. (ms)^-1

Definition at line 133 of file NhsContractionModel.hpp.

Referenced by EvaluateYDerivatives(), and NhsModelWithBackwardSolver::ImplicitSolveForQ().

const double NhsContractionModel::mAlpha3 = 0.625 [static, protected]

See reference. (ms)^-1

Definition at line 136 of file NhsContractionModel.hpp.

Referenced by EvaluateYDerivatives(), and NhsModelWithBackwardSolver::ImplicitSolveForQ().

The documentation for this class was generated from the following files:

heart/src/odes/contractionmodels/NhsContractionModel.hpp
heart/src/odes/contractionmodels/NhsContractionModel.cpp


Public Member Functions
	NhsContractionModel ()
void	SetStretchAndStretchRate (double lambda, double dlambdaDt)
void	SetInputParameters (ContractionModelInputParameters &rInputParameters)
void	SetIntracellularCalciumConcentration (double calciumConcentration)
double	GetCalciumTroponinValue ()
void	EvaluateYDerivatives (double time, const std::vector< double > &rY, std::vector< double > &rDY)
double	GetActiveTension ()
double	GetNextActiveTension ()
bool	IsStretchDependent ()
bool	IsStretchRateDependent ()
Protected Member Functions
void	CalculateCalciumTrop50 ()
double	CalculateT0 (double z)
Protected Attributes
double	mLambda
double	mDLambdaDt
double	mCalciumI
double	mCalciumTrop50
double	mK1
double	mK2
Static Protected Attributes
static const double	mKon = 100
static const double	mKrefoff = 0.2
static const double	mGamma = 2
static const double	mCalciumTroponinMax = 0.07
static const double	mAlphaR1 = 0.002
static const double	mAlphaR2 = 0.0017
static const double	mKZ = 0.15
static const unsigned	mNr = 3u
static const double	mBeta1 = -4
static const double	mAlpha0 = 0.008
static const unsigned	mN = 3u
static const double	mZp = 0.85
static const double	mCalcium50ref = 0.00105
static const double	mTref = 56.2
static const double	mBeta0 = 4.9
static const double	mA = 0.35
static const double	mA1 = -29
static const double	mA2 = 138
static const double	mA3 = 129
static const double	mAlpha1 = 0.03
static const double	mAlpha2 = 0.130
static const double	mAlpha3 = 0.625
Friends
class	TestContractionModels