A feasibility study of arrhythmia risk prediction in patients with myocardial infarction and preserved ejection fraction

Imaging-Based Simulations for Predicting Sudden Death and Guiding Ventricular Tachycardia Ablation

“…Scar region is considered electrically non-conductive, while finite elements that belonged to non-infarcted tissue and GZ are assigned regionally-uniform human ventricular cell action potential dynamics. Remodeled GZ ionic properties are represented by modifying the human action potential model with data from experimental recordings; detail can be found in recent publications 17,31–33 , showing GZ action potentials characterized by longer durations, decreased upstroke velocity and decreased peak amplitude. Tissue properties representing human ventricular cell-to-cell electrical communication are also assigned to the non-infarcted and GZ regions, with values of conductivities as described previously 17 .…”

“…Since all pacing sites are assigned automatically, typically using AHA nomenclature for segment locations, the number of pacing sites uniformly distributed throughout the left and right ventricles (LV and RV) can be chosen. In recent publications 17,33 , each virtual heart was paced from at least 19 different locations. The distribution of pacing sites throughout the ventricles, and particularly the LV, ensures that the protocol covers a large range of possibilities for potential sites at which ectopic foci could emerge and captures all the possible arrhythmias that could arise from the given structural remodeling distribution.…”

“…Because current guidelines for ICD placement target low LVEF patients who constitute only one-third of SCD victims 53 , VARP has the potential to identify increased SCD risk in a much larger number of at-risk patients. The first step in this direction was recently made by Deng et al 33 , who applied VARP in the analysis of data from 4 patients with MI and average LVEF of 44.0 ± 2.6%. VARP correctly predicted the occurrence of VT in one patient and the lack thereof in the remaining three, as shown in Figure 8.…”

“…Models from patients 2–4 (bottom row) demonstrated no inducible arrhythmia. Modified with permission from Deng et al 33 .…”

Towards personalized computational modelling of the fibrotic substrate for atrial arrhythmia

“…54,55 This includes studies aiming to estimate ablation targets for scar-related ventricular tachycardia 56 and stratify risk of lethal arrhythmias in post-myocardial infarction patients, including individuals for whom insertion of implantable defibrillators is clinically indicated 57 and (as discussed elsewhere in this supplement) those for whom it is not. 58 Furthermore, the field has now progressed to an exciting stage where computer modellers and clinicians are on the precipice of a truly thrilling collaboration that will involve the execution of catheter ablations in patients based on optimal treatment plans derived from pre-procedure simulations that take into account each individual's unique pattern of fibrotic structural remodelling. As this fascinating research trajectory continues to be explored in the future, the usefulness of its findings will depend on continuous adaptation and integration of new elements, including model redesign and evaluation, improvements in the execution time of biophysically detailed atrial models, implementation of consistent strategies for comparison with experimental and clinical measurements, and investment in efforts to ensure repeatability and consistency of simulation results.…”