Project Overview
The Interactive Left Atrium Model is a GPU-accelerated N-body computational simulation that enables real-time, interactive exploration of cardiac arrhythmias. Implemented in CUDA C++ with OpenGL visualization, this project combines physics-based cardiac muscle modeling with interactive ablation capabilities for both research and medical education.
Published: Journal of Electrocardiology, Volume 86 (2024), Article 153762 | DOI: 10.1016/j.jelectrocard.2024.153762
GPU-Accelerated
CUDA implementation on NVIDIA GPUs (Dual RTX A6000) for real-time interactive simulation of thousands of cardiac myocytes
Multidimensional Models
Validated progression from 1D strands to patient-specific 3D geometries from medical imaging
Clinically Relevant
Reproduces real arrhythmias (micro-reentry, flutter, SVT) and demonstrates ablation effectiveness
Quick Facts
- Programming: C++ with CUDA for GPU-accelerated parallel computing
- Graphics: OpenGL 3D rendering with ImGui interface and GLFW windowing
- Interactive Features: Real-time ablation tools, ectopic beat triggering, parameter adjustment during simulation
- Visualization: Multiple camera angles, Color coded contraction phases, video recording, screenshot capture
- Model Flexibility: Supports simple 1D strands to complex 13,000+ node patient-specific anatomies
- Open Source: Freely available on GitHub for research and educational use
Clinical Background
Cardiac Arrhythmias
Irregular heartbeats affect millions worldwide and are leading contributors to stroke and heart failure. The left atrium is the primary site of complex arrhythmias, particularly atrial fibrillation (AF) and supraventricular tachycardia (SVT).
Current Treatment
Catheter ablation is the gold standard intervention, but success rates vary widely (70-80%). Procedural planning relies heavily on operator experience rather than patient-specific computational modeling.
Our Solution
An interactive digital twin enables researchers and clinicians to understand arrhythmia mechanisms, test ablation strategies, and plan procedures without patient risk—all in real time.
Cardiac Muscle Physiology
Cardiac muscle has a unique property that distinguishes it from other muscle types: a long refractory period. This means that once the heart muscle contracts, it must wait before it can contract again. This built-in delay is essential for proper heart function, ensuring that the heart chambers fill with blood between beats. Our model simulates this critical physiological behavior, allowing researchers to study how disruptions in this timing can lead to arrhythmias.
Model Architecture & Validation
Technical Architecture
Our model uses an N-body simulation approach where individual nodes represent cardiac muscle cells (myocytes) connected by virtual muscle fibers. These connections allow electrical signals to propagate through the tissue, mimicking how real heart muscle conducts impulses. The model captures both electrical activation and mechanical contraction, enabling users to observe and manipulate cardiac behavior in real-time. This interactive framework makes it possible to induce arrhythmias and test virtual ablation strategies.
The model was systematically validated through dimensional progression, starting with simple geometries and advancing to anatomically accurate structures:
1D Strand (11 nodes)
Validated electrical wavefront propagation and conduction blockage. The fundamental unit for testing signal transmission.
2D Ring (24–200 nodes)
Demonstrated macro-reentrant circuits and reentry tachycardia. Tests boundary conditions and circular wave propagation.
3D Sphere (340–5,680 nodes)
Stable 3D spiral wave dynamics and multidirectional propagation. Validates 3D behavior before anatomical complexity.
Idealized LA (13,000 nodes)
Anatomical features: pulmonary veins, mitral valve, Bachmann's bundle. Tests realistic geometry before patient data.
Patient-Specific LA
Real left atrial geometries from medical imaging (CTA, MRI). Clinically relevant models for arrhythmia reproduction and ablation planning.
Research Results
The digital twin successfully reproduced multiple clinically relevant arrhythmia mechanisms observed in patients. By adjusting conduction velocities and applying precisely timed ectopic events, we induced various forms of reentrant activity including micro-reentry, macro-reentry, and atrial flutter. These arrhythmias demonstrated self-sustaining propagation patterns consistent with clinical observations.
Arrhythmia Induction
We successfully induced left atrial flutter by slowing conduction velocity between pulmonary vein openings and triggering ectopic events at specific locations and times. Reentrant circuits and rotors emerged naturally, producing sustained activation patterns that resembled those seen in real patients.
Virtual Ablation
Simulated catheter ablation reliably terminated reentrant activity and restored organized conduction patterns. We successfully eliminated induced flutters using virtual ablations, allowing the system to return to normal rhythm. The model demonstrated effectiveness on both idealized and patient-specific atrial geometries.
Interactive Features
The interactive GUI lets you trigger single ectopic events, schedule recurring ectopic beats, perform virtual ablations, and adjust beat period and visualization—all in real time without digging through menus.
Mouse-Based Interventions
- Ablate: Block electrical conduction in selected regions
- Ectopic Trigger: Initiate single beats from chosen locations
- Ectopic Beat: Create recurrent pacing from specific nodes
- Adjust Area: Modify muscle contractile properties in real time
- Identify Node: Query individual node IDs and states
Visualization & Control
- 3D Rotation & Zoom: Freely rotate and inspect geometry
- Node Coloring: Toggle Color coded contraction phases
- Draw Front Half: Render only near half for clarity
- Recording: Capture simulation videos for analysis
- Beat Period Control: Adjust heart rate (millisecond precision)
- Simulation Speed: Adjust computational rate independent of display
Data Management
- Save/Load State: Persist and restore complete simulation configurations
- Export Settings: Save parameters for reproducible experiments
- Import Configuration: Load pre-defined model setups
Research Team
PI & Co-Investigators
Principal Investigator:
Dr. Bryant Wyatt
Tarleton State University, Department of Mathematics
Co-Investigator:
Dr. Charles Puelz
University of Houston, Department of Mathematics
Collaborators & Team
- Mason Bane
- Leah Rogers
- Kyla Moore
- Philip Alcorn
- Melanie Little
- Avery Campbell
- Gavin McIntosh
- Gabriella Williams
- Kinsey Brawner
- Brandon Wyatt — Biosense Webster
Funding & Support
- NIH Grant: #1R15HL179671-01
- NVIDIA: Applied Research Accelerator Program
- Tarleton State University: Presidential Excellence in Research
- Bill & Winnie Wyatt Foundation
Recognition
Accepted Poster Presentation
1st Place Poster
1st Place Undergraduate Poster
Publications
Studying Left Atrial Arrhythmias Using a Real-Time Interactive Digital Twin
Heart Rhythm O2, 6(9):S2
Published: September 2025
Simulating left atrial arrhythmias with an interactive N-body model
Journal of Electrocardiology, 86 (2024), 153762
Published: July 22, 2024 | Open Access
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