Background: Experimental mapping and computer modelling provide important platforms to study the fundamental mechanisms underlying normal and abnormal activation of the heart. However, accurate computer modelling requires detailed anatomical models and needs support and validation from experimental data. Aims: 1) Construction of detailed anatomical heart models with the cardiac conduction system (CCS). 2) Mapping of the electrical activation sequence in rabbit atria to support and validate computer simulation. 3) Mapping of the spontaneous activity in the atrioventricular ring tissues (AV rings), which consist of nodal-like myocytes and can be a source of atrial tachycardia. Methods: High-resolution magnetic resonance imaging (MRI) and computed tomography (CT) were used to provide two-dimensional (2D) images for the construction of the detailed anatomical heart models. Immunohistochemistry and Masson's trichrome staining were used to distinguish the CCS in the heart. LabVIEW was used in the development of a multi-electrode mapping system. The multi-electrode mapping technique was employed to map the electrical activation sequence of the rabbit atria. The cellular automaton model was used to simulate electrical activation of the rabbit atria. Results: 1) Three detailed anatomical models were constructed, including a detailed three dimensional (3D) anatomical model of the rabbit heart (whole of the atria and part of the ventricles), a 3D anatomical model of the rat heart with the CCS and AV rings, and a 3D anatomical model of the human atrioventricular node. 2) A multi-electrode mapping system was developed. 3) The electrical activation sequence of the rabbit atria was mapped in detail using the multi-electrode mapping system. The conduction velocity in the rabbit atria was measured. The mapping data showed the coronary sinus and the left superior vena cava do not provide an interatrial conduction route during sinus rhythm in the rabbit heart. 4) Electrical activation of the rabbit atria was simulated with the support of the 3D anatomical model of the rabbit atria and the experimental mapping data. 5) The spontaneous activity in the rat AV rings was mapped using the multi-electrode mapping system. Conclusions: The detailed anatomical models developed in this study can be used to support accurate computer simulation and can also be used in anatomical teaching and research. The experimental mapping data from the rabbit atria can be used to support and validate computer simulation. The computer simulation study demonstrated the importance of anatomical structure and electrophysiological heterogeneity. This study also demonstrated that the AV rings could potentially act as ectopic pacemakers.
|Date of Award||1 Aug 2013|
- The University of Manchester
|Supervisor||Mark Boyett (Supervisor) & Halina Dobrzynski (Supervisor)|
- computer simulation
- rabbit atria
- atrioventricular ring tissues
- 3D anatomical model