In an example of excellence in cross-disciplinary work, researchers at The University of Manchester’s School of Physics and Astronomy created a functioning virtual replica of a sheep heart to better study how it functions. The simulation was created by slicing a real sheep heart using a microtome, photographing each slice, and then rendering a composite of the 3D volume using a computer algorithm.
The fiber structure and the electrical activity within the relevant parts of the heart were also modeled into the representation, allowing for the researchers to study atrial fibrillation (AF), hopefully leading to new clinical approaches to treating the disease.
From U of Manchester:
Professor Zhang and his team focussed on the pulmonary vein which is a common area that initially triggers AF. They simulated erratic electrical waves passing through the vein and the surrounding atrial tissue, and then studied the impact this had on the rest of the heart.
What they found was that regional differences in the electrical activity across the tissue of the heart, known as electrical heterogeneity, is key to the initiation of AF. The largest electrical difference was between the pulmonary vein and the left atrium which may go some way to explaining why the pulmonary vein region is a common source of irregular heartbeats.
The scientists also identified that the fibre structure of the heart plays an important role in the development of AF. There were directional variations in the conduction of electrical waves along and across the fibres, this is known as anisotropy. The fibre structure in the left atrium is much more organised compared with the complex structures of the pulmonary vein region. The sudden variation in conduction at the junction between the left atrium and the pulmonary vein regions appeared to contribute to the development of AF.
Professor Zhang says: “This study has for the first time identified the individual role of electrical heterogeneity and fibre structure in the initiation and development of AF. It has not previously been possible to study the contribution of the two separately but using our computational model we’ve been able to clearly see that both electrical heterogeneity and fibre structure need to be taken into consideration when treatment strategies for AF are being devised.”
The next step for Professor Zhang and his team will be to find a way to target the electrical conduction in specific regions of the heart to better protect against AF. They also want to use their virtual heart to gain a deeper understands of AF and to apply their findings to the development of more effective treatments.
Press release: Virtual heart sheds new light on heart defect