RESUMEN
OBJECTIVE@#In this study,computational modelling was used to study whether different conduction pathways have impact on the AF initiation and maintenance based on a human atrial model.@*METHODS@#MRI images from one patient who has atrial fibrillation were used to reconstruct the human atrial anatomical model.The number of MRI images was 112.In order to study the effect of different conduction pathways to AF,4 different atrial models were generated in this study,which were biatrial conduction via only LFO;biatrial conduction via only CS;biatrial conduction via both LFO and CS;model without biatrial conduction.@*RESULTS@#In the case of biatrial conduction simulation via only LFO,the same re-entries were induced as in the LFO and CS case.But for the two cases of only CS conduction and both LFO and CS cannot conduct electricity,one stimulus site induced unsustained re-entry which only lasted for 2 cycles,and then terminated.The other two sites induced the same re-entries as in the previously described two cases,which were biatrial conduction simulation via both LFO and CS and only LFO.@*CONCLUSIONS@#Our simulation showed that these conduction pathways played a minor role in the re-entry initiation and maintenance,the possible explanation is that all the re-entries induced in our simulation is local drivers and maintained by fibrosis.
Asunto(s)
Humanos , Fibrilación Atrial , Ablación por Catéter , Atrios Cardíacos , Frecuencia CardíacaRESUMEN
Two clinical ablation protocols,2C3L and stepwise,have been routinely used in our group to treat atrial fibrillation (AF),but with a less than 60％ long-term arrhythmia-free outcome achieved in patients.The goal of this study was to examine the underlying mechanism of low success in clinical outcome.MRI images from one patient were used to reconstruct a human atrial anatomical model,and fibrotic tissue was manually added to represent the arrhythmia substrate.AF was induced with standard protocols used in clinical practice.2C3L and stepwise were then used to test the efficacy of arrhythmia termination in our model.The results showed that re-entries induced in our model could not be terminated by using either 2C3L or the stepwise protocol.Although some of the induced re-entries were terminated,others emerged in new areas.Ablation using only the 2C3L or stepwise method was not sufficient to terminate all re-entries in our model,which may partially explain the poor long-term arrhythmiafree outcomes in clinical practice.Our findings also suggest that computational heart modelling is an important tool to assist in the establishment of optimal ablation strategies.
RESUMEN
Two clinical ablation protocols,2C3L and stepwise,have been routinely used in our group to treat atrial fibrillation (AF),but with a less than 60％ long-term arrhythmia-free outcome achieved in patients.The goal of this study was to examine the underlying mechanism of low success in clinical outcome.MRI images from one patient were used to reconstruct a human atrial anatomical model,and fibrotic tissue was manually added to represent the arrhythmia substrate.AF was induced with standard protocols used in clinical practice.2C3L and stepwise were then used to test the efficacy of arrhythmia termination in our model.The results showed that re-entries induced in our model could not be terminated by using either 2C3L or the stepwise protocol.Although some of the induced re-entries were terminated,others emerged in new areas.Ablation using only the 2C3L or stepwise method was not sufficient to terminate all re-entries in our model,which may partially explain the poor long-term arrhythmiafree outcomes in clinical practice.Our findings also suggest that computational heart modelling is an important tool to assist in the establishment of optimal ablation strategies.