Computational Modelling of Electro-Mechanical Coupling in the Atria and Its Changes During Atrial Fibrillation

TY - GEN

T1 - Computational Modelling of Electro-Mechanical Coupling in the Atria and Its Changes During Atrial Fibrillation

AU - Monaci, Sofia

AU - Nordsletten, David

AU - Aslanidi, Oleg

PY - 2019/2/14

Y1 - 2019/2/14

N2 - Atrial fibrillation (AF) is a very common, multifaceted disease that affects atrial structure as well as electrophysiological and biomechanical function. However, the mechanistic links between structural and functional factors underlying AF are poorly understood. To explore these mechanisms, a 3D atrial electro-mechanical (EM) model was developed that includes 3D atrial geometry based on the Visible Female dataset, rule-based fibre orientation, CRN human atrial electrophysiology model and activation-based mechanical contraction model. Electrical activation in the 3D atria was simulated under control condition and two AF scenarios: sinus rhythm (SR), functional re-entry in the right atrium (RA) and structural re-entry around fibrotic patches in the left atrium (LA). Fibrosis distributions were obtained from patient LGE MRI data. In both AF scenarios, re-entrant behaviours led to substantial reductions in the displacement at peak contraction compared to SR. Specifically, high-frequency re-entry led to a decrease in maximal displacement from 6.8 to 6.1 mm in the posterior RA, and a larger decrease from 7.8 to 4.5 mm in the LA in the presence of fibrotic patches. The simulated displacement values agreed with available clinical data. In conclusion, the novel model of EM coupling in the 3D human atria provided new insights into the mechanistic links between atrial electrics and mechanics during normal activation and re-entry sustaining AF. Re-entry in the RA and LA resulted in weaker contractions compared to SR, with additional effect of fibrosis on the atrial wall stiffness further reducing the contraction.

AB - Atrial fibrillation (AF) is a very common, multifaceted disease that affects atrial structure as well as electrophysiological and biomechanical function. However, the mechanistic links between structural and functional factors underlying AF are poorly understood. To explore these mechanisms, a 3D atrial electro-mechanical (EM) model was developed that includes 3D atrial geometry based on the Visible Female dataset, rule-based fibre orientation, CRN human atrial electrophysiology model and activation-based mechanical contraction model. Electrical activation in the 3D atria was simulated under control condition and two AF scenarios: sinus rhythm (SR), functional re-entry in the right atrium (RA) and structural re-entry around fibrotic patches in the left atrium (LA). Fibrosis distributions were obtained from patient LGE MRI data. In both AF scenarios, re-entrant behaviours led to substantial reductions in the displacement at peak contraction compared to SR. Specifically, high-frequency re-entry led to a decrease in maximal displacement from 6.8 to 6.1 mm in the posterior RA, and a larger decrease from 7.8 to 4.5 mm in the LA in the presence of fibrotic patches. The simulated displacement values agreed with available clinical data. In conclusion, the novel model of EM coupling in the 3D human atria provided new insights into the mechanistic links between atrial electrics and mechanics during normal activation and re-entry sustaining AF. Re-entry in the RA and LA resulted in weaker contractions compared to SR, with additional effect of fibrosis on the atrial wall stiffness further reducing the contraction.

KW - Atrial fibrillation

KW - Electro-mechanical coupling

KW - Fibrosis

KW - Mechanical contraction

KW - Re-entry

KW - Sinus rhythm

UR - http://www.scopus.com/inward/record.url?scp=85064053043&partnerID=8YFLogxK

U2 - 10.1007/978-3-030-12029-0_12

DO - 10.1007/978-3-030-12029-0_12

M3 - Conference contribution

SN - 978-3-030-12028-3

VL - 11395

SP - 103

EP - 113

BT - Lecture Notes in Computer Science

A2 - Zhao, Jichao

A2 - Sermesant, Maxime

A2 - Young, Alistair

A2 - Rhode, Kawal

A2 - Li, Shuo

A2 - McLeod, Kristin

A2 - Pop, Mihaela

A2 - Mansi, Tommaso

PB - Springer‐Verlag Berlin Heidelberg

ER -