Quentin Gillardin, V. Rolle, Anca Nica, A. Biraben, Benoît Martin, Alfredo I. Hernández
{"title":"Recursive Model Identification for the Analysis of Cardiovascular Autonomic Modulation During Epileptic Seizure","authors":"Quentin Gillardin, V. Rolle, Anca Nica, A. Biraben, Benoît Martin, Alfredo I. Hernández","doi":"10.22489/CinC.2020.206","DOIUrl":"https://doi.org/10.22489/CinC.2020.206","url":null,"abstract":"Significant cardio-respiratory fluctuations are often observed during and after an epileptic seizure event. The mechanisms underlying these acute modifications are considered to be involved in sudden and unexpected death in epilepsy (SUDEP). We hypothesize that these acute events are mediated by specific dynamics of the autonomic nervous system (ANS). However, the evaluation of the ANS during seizures remains particularly challenging, mainly due to the lack of observability. Computational modelling could help to override these limitations, to assess ANS modulation and to evaluate this hypothesis. In this study, we propose and apply a recursive identification algorithm of a system-level model of the autonomic modulation of the sino-atrial node, integrating a Tikhonov regularization, in order to assess sympathetic and parasympathetic activities during ictal tachy-bradycardia events. We evaluate the feasibility of the method on heart rate (HR) data from 4 seizures observed in the same patient. After parameter optimization and identification we were able to reproduce observed HR data with a maximum root mean squared error equals to 1.7bpm. The estimated autonomic series show sympathetic activation and parasympathetic inhibition at the seizure onset, and a massive vagal discharge as the leading factor to ictal bradycardia.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114477738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Young, J. Ramírez, S. Duijvenboden, A. Tinker, P. Lambiase, P. Munroe, M. Orini
{"title":"Will Genetic Data Significantly Change Cardiovascular Risk Prediction in Daily Practice?","authors":"W. Young, J. Ramírez, S. Duijvenboden, A. Tinker, P. Lambiase, P. Munroe, M. Orini","doi":"10.22489/CinC.2020.481","DOIUrl":"https://doi.org/10.22489/CinC.2020.481","url":null,"abstract":"Precision medicine has been heralded as an opportunity to improve risk prediction, driven significantly by an increasing availability of genetic data. Genetic testing for rare mutations linked with Mendelian monogenic syndromes is available in specialised clinics. For complex diseases however, aggregation of common and low frequency variants into a “polygenic risk score” (PRS) is necessary due to their small individual effect sizes. PRSs for coronary artery disease (CAD), hypertension and atrial fibrillation have shown some modest success at a population level. However, scepticism remains whether the genetic effects in CV disease are sufficient to have meaningful clinical impact. This review explores recent efforts to utilise genomic data for risk prediction using CAD as an example.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"142 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116587185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Breakthrough Wave Detection in a 3D Computer Model of Atrial Endo-Epicardial Dissociation","authors":"Eric Irakoze, V. Jacquemet","doi":"10.22489/CinC.2020.425","DOIUrl":"https://doi.org/10.22489/CinC.2020.425","url":null,"abstract":"Experimental and clinical mapping of atrial fibrillation has revealed the occurrence of breakthrough activation patterns. These focal waves have been associated with endo-epicardial (endo-epi) dissociation and three-dimensional anatomical structures. To assess breakthrough detection techniques in computer models of atrial fibrillation, we created a 3D cubic-mesh atrial model with locally controllable endo-epi dissociation. In this model, epi and endo layers were electrically coupled only at randomly-distributed discrete connection sites. Eighteen endo-epi connection patterns were generated. Dedicated finite-difference numerical methods were developed to handle these discontinuities in conduction. These configurations were designed to generate breakthroughs at predictable locations. We developed a breakthrough detection algorithm based on full-resolution activation maps of both the epi- and endocardial surfaces. Wave tracking was used to calculate the lifespan of breakthroughs. Non-propagating passive responses and breakthroughs with too short lifespan were eliminated. The approach was manually and automatically validated in 48 episodes of fibrillation in models with varying number of endo-epi connections.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117049391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amina Ghrissi, F. Squara, J. Montagnat, V. Zarzoso
{"title":"Identification of Ablation Sites in Persistent Atrial Fibrillation Based on Spatiotemporal Dispersion of Electrograms Using Machine Learning","authors":"Amina Ghrissi, F. Squara, J. Montagnat, V. Zarzoso","doi":"10.22489/CinC.2020.221","DOIUrl":"https://doi.org/10.22489/CinC.2020.221","url":null,"abstract":"A recent patient-tailored ablation protocol to treat atrial fibrillation consists in identifying ablation sites based on their spatiotemporal dispersion (STD). STD represents a delay of the cardiac activation observed in intracardiac electrograms (EGMs) across contiguous leads. This work aims at automatically identifying ablation sites by classifying EGM data acquired by the PentaRay catheter into ablated vs. non-ablated groups using machine learning. More than 35000 multichannel recordings are acquired from 15 persistent AF patients. An annotation model is designed to label the dataset. The classifiers include: (1) multivariate logistic regression; (2) LeNet-STD, a shallow convolutional neural network. A binary label identifying whether the mapped site contains STD pattern according to the interventional cardiologist is combined to raw EGMs as classifiers input. The LeNet-STD combined with data augmentation yields the best performance with an F1-score of 76%.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123153902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multi-Class Classification of Pathologies Found on Short ECG Signals","authors":"G. Nalbantov, Svetoslav Ivanov, J. V. Prehn","doi":"10.22489/CinC.2020.071","DOIUrl":"https://doi.org/10.22489/CinC.2020.071","url":null,"abstract":"The ability to detect several key cardiac pathologies simultaneously, based on ECG signals, is key towards establishing a real-world application of AI models in cardiology. Such a multi-label classification task requires not only well-performing binary classification models, but also a way to combine such models into an overall classification modeling structure. We have approached this task using materials from Classification of 12-1ead ECGs for the PhysioNet/Computing in Cardiology Challenge 2020. Duplicate ECG strips have been removed. An annotation tool for labeling ECG wave points and intervals/templates has been created in MATLAB®, and used for labeling pathological intervals, as well as noisy intervals and inconsistencies between the ECG data and the pre-assigned labels. Several one-vs-rest binary classifiers were built, where morphological features specific to each pathology had been generated from the signals. The binary classifiers were augmented by a multi-class classifier using an Error Correcting Output Codes (ECOC) methodology. Our approach achieved a challenge validation score of 0.616, and full test score of 0.194, placing us 23 (team DSC) out of 41 in the official ranking.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121389961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multi-Label Classification of 12-lead ECGs by Using Residual CNN and Class-Wise Attention","authors":"Yang Liu, Kuanquan Wang, Yongfeng Yuan, Qince Li, Yacong Li, Yongpeng Xu, Henggui Zhang","doi":"10.22489/CinC.2020.285","DOIUrl":"https://doi.org/10.22489/CinC.2020.285","url":null,"abstract":"Cardiovascular diseases have become the leading cause of illness and death worldwide. Due to their chronic nature, early screening and follow-up management will effectively improve the prevention and treatment of cardiovascular diseases, where automatic electrocardiogram (ECG) classification will play an important role. In this work, we take part in the 2020 PhysioNet - CinC Challenge (in the team ECGMaster) and propose a novel multi-label classifier of 12-lead ECG recordings which combines a residual convolutional network (residual CNN) with a class-wise attention mechanism. To deal with the problem of data imbalance between classes, we utilize a novel weighted focal loss in the training of our models. Our models were trained and tested in a 5-fold cross validation on the training data with resulting scores of 0.5501 ± 0.0223 according to the challenge metric, demonstrating a promising method for the classification of ECGs. We note that we were unable to score and rank our model on the official test data, the results were obtained on the training set only and may be over-optimistic.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125530191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Proarrhythmia in KCNJ2 E299V-linked Short QT Syndrome: A Simulation Study","authors":"Cunjin Luo, Tong Liu, Ying He, Kuanquan Wang, Henggui Zhang","doi":"10.22489/CinC.2020.432","DOIUrl":"https://doi.org/10.22489/CinC.2020.432","url":null,"abstract":"Short QT syndrome (SQTS) is a clinical disorder associated with cardiac arrhythmias and sudden cardiac death (SCD). Short QT syndrome variant 3 (SQT3) has been linked to the D172N or E299V gain-in-function mutation to Kir2.1, which preferentially increases outward current through channels responsible for inward rectifier K+ current $(I_{K1})$. There is a novel blocker of Kir2.1, Styrax, which is a kind of natural compound selected from traditional Chinese medicine. In this study, the ten Tusscher et al model of ventricular action potential was used to investigate the potential effects of Styrax on the short QT syndrome associated with the Kir2.1 D172N mutation and E299V mutation. Our data showed that Styrax can prolong the action potential (AP) and QT interval on the ECG under the condition of SQT3 associated with D172N and E299V mutations. We suggested that Styrax may be a potential drug for the treatment of SQT3.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"172 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126401573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"More Reliable Remote Heart Rate Measurement by Signal Quality Indexes","authors":"Hannes Ernst, H. Malberg, Martin Schmidt","doi":"10.22489/CinC.2020.165","DOIUrl":"https://doi.org/10.22489/CinC.2020.165","url":null,"abstract":"Accuracy of camera-based heart rate $(HR_{cb)}$ measurement is often impaired by artifacts, which leads to erroneous $HR_{cb}$ and reduced confidence in the measurement. To avoid erroneous $HR_{cb}$, we investigated six signal quality indexes (SQIs) from the literature in terms of their effect size and combined them to a novel SQI-filter. All analyses were performed on the “Binghamton-Pitts-burgh-RPI Multimodal Spontaneous Emotion Database” (BP4D+) in three important color channels. Signal-to-noise ratio, average maximum cross correlation of consecutive segments, and relative difference of spectral peaks were the most powerful SQIs. The SQI-filter increased accuracies of all color channels. Largest improvements (up to 60 %) were achieved in the green channel resulting in 80 % accuracy. The overall highest accuracy of 84 % was reached in the hue channel. Motion-rich videos benefited most from the developed SQI-filter. The presented methodology helps to discard distorted signals. This enables more reliable $HR_{cb}$ data in further applications and increases confidence in the measurement.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129269461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
X. Jaureguibeitia, U. Irusta, E. Aramendi, He Wang, A. Idris
{"title":"An Impedance-based Algorithm to Detect Ventilations During Cardiopulmonary Resuscitation","authors":"X. Jaureguibeitia, U. Irusta, E. Aramendi, He Wang, A. Idris","doi":"10.22489/CinC.2020.325","DOIUrl":"https://doi.org/10.22489/CinC.2020.325","url":null,"abstract":"Cardiopulmonary resuscitation (CPR) is a core therapy to treat out-of-hospital cardiac arrest (OHCA). Thoracic impedance (TI) can be used to assess ventilations during CPR, but the signal is also affected by chest compression (CC) artifacts. This study presents a method for TI-based ventilation detection during concurrent manual CCs. Data from 152 OHCA patients were analyzed. A total of 423 TI segments of at least 60 s during ongoing CCs were extracted. True ventilations were annotated using the capnogram. The final dataset comprised 1210 min of TI recordings and 9665 ground truth ventilations. A three-stage detection algorithm was developed. First, the TI signal was filtered to obtain ventilation waveforms, including a least mean squares filter to remove artifacts due to CCs. Potential ventilations were then identified with a heuristic detector and characterized by a set of 16 features. These were finally fed to a random forest classifier to discriminate between true ventilations and false positives. Patients were split into 100 distinct training (70%) and test (30%) partitions. The median (interquartile range) sensitivity, PPV and F-score were 83.9 (70.2-91.2) %, 86.1 (75.0-93.3) % and 84.3 (72.1-91.4) %. Our method would allow feedback on ventilation rates as well as surrogate measures of insufflated air volume during CPR.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128277540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Srinivasan, Hassaan A. Bukhari, P. Laguna, C. Sánchez, E. Pueyo
{"title":"Analysis of T Wave Nonlinear Dynamics for Serum Potassium Monitoring in End-Stage Renal Disease Patients","authors":"S. Srinivasan, Hassaan A. Bukhari, P. Laguna, C. Sánchez, E. Pueyo","doi":"10.22489/CinC.2020.461","DOIUrl":"https://doi.org/10.22489/CinC.2020.461","url":null,"abstract":"Non-invasive estimation of serum potassium, [K+], is of major importance to prevent associated risks, but current ambulatory estimation methods are limited. We investigated changes in T wave nonlinear dynamics by quantifying a divergence-related marker ψ on electrocardiograms (ECGs) from 15 end-stage renal disease (ESRD) patients undergoing hemodialysis (HD) and we assessed the relationship between ψ and [K+]. ECGs from 22 simulated transmural ventricular fibers were additionally calculated. In ESRD patients, ψ took the largest values at the beginning and end of the HD session, corresponding to the highest and lowest [K+] values. The median correlation coefficient over patients between the change in ψ and the change in [K+] was 0.92 and decreased to 0.74 after controlling for the effects of [Ca2+] and heart rate. These associations were, however, highly patient-dependent. Both the strength and variability of the ψ -[K+] relationship was reproduced in the simulations, with the variability explained by differences in transmural heterogeneities: 10% variations in the proportion of epicardial and midmyocardial cells led to more than 10% and 8% changes in ψ, respectively. In conclusion, changes in the nonlinear dynamics of the ECG T waves can be related to [K+] variations in ESRD patients, despite the high inter-individual variability.","PeriodicalId":407282,"journal":{"name":"2020 Computing in Cardiology","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124563683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}