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Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology.

Krishnamoorthi S, Perotti LE, Borgstrom NP, Ajijola OA, Frid A, Ponnaluri AV, Weiss JN, Qu Z, Klug WS, Ennis DB, Garfinkel A - PLoS ONE (2014)

Bottom Line: We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG) and the activation wavefronts over time.We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential.Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical and Aerospace Engineering, University of California Los Angeles, Los Angeles, California, United States of America.

ABSTRACT
We describe a sequence of methods to produce a partial differential equation model of the electrical activation of the ventricles. In our framework, we incorporate the anatomy and cardiac microstructure obtained from magnetic resonance imaging and diffusion tensor imaging of a New Zealand White rabbit, the Purkinje structure and the Purkinje-muscle junctions, and an electrophysiologically accurate model of the ventricular myocytes and tissue, which includes transmural and apex-to-base gradients of action potential characteristics. We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG) and the activation wavefronts over time. We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential. These include producing a physiologically accurate ECG, a correct ventricular activation sequence, and the inducibility of ventricular fibrillation. Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations.

No MeSH data available.


Related in: MedlinePlus

Sustained wave breakup and chaotic meandering during simulated Ventricular Fibrillation (VF).VF was induced using an S1-S2 protocol with the second stimulus applied between  and . The voltage contour plot is shown at .
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pone-0114494-g010: Sustained wave breakup and chaotic meandering during simulated Ventricular Fibrillation (VF).VF was induced using an S1-S2 protocol with the second stimulus applied between and . The voltage contour plot is shown at .

Mentions: In a normal heart, one strong second stimulus (S2) delivered in the refractory tail of the previous wave (stimulated by a normal S1) can initiate reentry [40], [43]–[45]. Under pro-arrhythmic conditions, once initiated, reentry is unstable, and, within seconds, breaks up into a multi-wave chaotic state in which wavefronts are being continually generated and extinguished [40], [43], [46]. In small electrical substrates such as a rabbit heart, sustained chaotic wave break-up can be induced by decreasing conduction velocity [43]. We observed sustained fibrillation in our primary model (described in the beginning of the “Results" section) with reduced by 25%. Application of a stimulus of in a 60-degree wedge-shaped region of the LV freewall covering half the height of the heart (S2) at 219ms following normal Purkinje activation (S1) initiated a reentrant wave. This wave broke up into a sustained multi-wave state representing ventricular fibrillation (Fig. 10 and voltage propagation video provided as supplementary material as S2 Movie and S3 Movie).


Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology.

Krishnamoorthi S, Perotti LE, Borgstrom NP, Ajijola OA, Frid A, Ponnaluri AV, Weiss JN, Qu Z, Klug WS, Ennis DB, Garfinkel A - PLoS ONE (2014)

Sustained wave breakup and chaotic meandering during simulated Ventricular Fibrillation (VF).VF was induced using an S1-S2 protocol with the second stimulus applied between  and . The voltage contour plot is shown at .
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4262432&req=5

pone-0114494-g010: Sustained wave breakup and chaotic meandering during simulated Ventricular Fibrillation (VF).VF was induced using an S1-S2 protocol with the second stimulus applied between and . The voltage contour plot is shown at .
Mentions: In a normal heart, one strong second stimulus (S2) delivered in the refractory tail of the previous wave (stimulated by a normal S1) can initiate reentry [40], [43]–[45]. Under pro-arrhythmic conditions, once initiated, reentry is unstable, and, within seconds, breaks up into a multi-wave chaotic state in which wavefronts are being continually generated and extinguished [40], [43], [46]. In small electrical substrates such as a rabbit heart, sustained chaotic wave break-up can be induced by decreasing conduction velocity [43]. We observed sustained fibrillation in our primary model (described in the beginning of the “Results" section) with reduced by 25%. Application of a stimulus of in a 60-degree wedge-shaped region of the LV freewall covering half the height of the heart (S2) at 219ms following normal Purkinje activation (S1) initiated a reentrant wave. This wave broke up into a sustained multi-wave state representing ventricular fibrillation (Fig. 10 and voltage propagation video provided as supplementary material as S2 Movie and S3 Movie).

Bottom Line: We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG) and the activation wavefronts over time.We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential.Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical and Aerospace Engineering, University of California Los Angeles, Los Angeles, California, United States of America.

ABSTRACT
We describe a sequence of methods to produce a partial differential equation model of the electrical activation of the ventricles. In our framework, we incorporate the anatomy and cardiac microstructure obtained from magnetic resonance imaging and diffusion tensor imaging of a New Zealand White rabbit, the Purkinje structure and the Purkinje-muscle junctions, and an electrophysiologically accurate model of the ventricular myocytes and tissue, which includes transmural and apex-to-base gradients of action potential characteristics. We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG) and the activation wavefronts over time. We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential. These include producing a physiologically accurate ECG, a correct ventricular activation sequence, and the inducibility of ventricular fibrillation. Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations.

No MeSH data available.


Related in: MedlinePlus