Related Experiment Video

Updated: Feb 23, 2026

Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations

Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations

Published on: January 8, 2013

Simulation study of the ionic mechanisms underlying Torsade de Pointes in a 2D cardiac tissue

Ponnuraj Kirthi Priya¹, M Ramasubba Reddy¹

¹Biomedical Engineering Group, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai 600036, India.

Computers in Biology and Medicine

|September 1, 2017

Abstract

Background:

To understand the ionic mechanism behind the genesis of Torsade de Pointes (TdP) occurring with long QT syndrome 2 (LQTS2) in a remodelled transmural tissue.

Methods:

The TP06 model is used to simulate the electrical activity of cells in a 2D transmural ventricular model. LQTS2 is realised by reducing the potassium current (I_Kr) to 0.5 in each cell. Each cell of the tissue is remodelled by increasing the conductance of calcium current (G_CaL). The above two factors make the cells prone to early after depolarizations (EADs) development. The rise in G_CaL that can develop a sustained TdP at normal pacing rate is determined from this study. A look at the calcium dynamics, sodium-calcium exchanger current (I_NaCa) and slow delayed rectifier potassium current (I_Ks) distribution maps of the tissue helps us in analysing the mechanism of TdP generation.

Results:

A TdP type pattern at normal pacing rate is generated when G_CaL is more than 3.5 times the control parameter. From the M-cell island, an adequate number of cells spontaneously release calcium from their sarcoplasmic reticulum leading to increased intracellular calcium and inward sodium current through the sodium calcium exchanger current (I_NaCa). These contribute to the development of EADs which create a depolarising wavefront that triggers TdP in the tissue. When G_CaL is less than 3.5 times the control value, premature ventricular complexes (PVC) occur interspersed between normal beats.

Conclusion:

Normal pacing rates can induce a multi focal TdP when sufficient number of M-cells simultaneously undergo spontaneous calcium release (SCR) events.

Keywords:

Early afterdepolarization Long QT syndrome 2 Spontaneous calcium release Torsade de Pointes Ventricular remodelling

More Related Videos

Creating a Structurally Realistic Finite Element Geometric Model of a Cardiomyocyte to Study the Role of Cellular Architecture in Cardiomyocyte Systems Biology

Creating a Structurally Realistic Finite Element Geometric Model of a Cardiomyocyte to Study the Role of Cellular Architecture in Cardiomyocyte Systems Biology

Published on: April 18, 2018

In Silico Clinical Trials for Cardiovascular Disease

In Silico Clinical Trials for Cardiovascular Disease

Published on: May 27, 2022

Related Concept Videos

Mechanism of Cardiac Arrhythmias

Mechanism of Cardiac Arrhythmias

Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.

Cardiac Action Potential

Cardiac Action Potential

Cardiac action potentials are essential for proper heart function, enabling the rhythmic contractions needed for adequate blood circulation. Nodal cells and Purkinje fibers, specialized for electrical conduction, generate these action potentials.
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials

Electrophysiology of Normal Cardiac Rhythm

Electrophysiology of Normal Cardiac Rhythm

The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase...

Articles linked to this work by shared authors, journal, and citation graph.

CNN models in time-frequency domain for identification of motor imagery tasks from EEG signals.

Physical and engineering sciences in medicine·2026

Enhancing the performance of a deep convolutional neural network model for motor imagery classification using EEG channel-wise attention module.

Medical engineering & physics·2026

Frontal EEG correlation based human emotion identification and classification.

Physical and engineering sciences in medicine·2024

Narrow band-pass filtered canonical correlation analysis for frequency identification in SSVEP signals.

Biomedical physics & engineering express·2024

Classification of Motor Imagery EEG signals using high resolution time-frequency representations and convolutional neural network.

Biomedical physics & engineering express·2024

Performance of Empirical Mode Decomposition for Frequency Identification in SSVEP Based BCI.

Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference·2023

See all related articles