M. Jennings, A. Rababah, Daniel Güldenring, J. Mclaughlin, D. Finlay
{"title":"Coefficients for the Derivation of an ST Sensitive Patch Based Lead System from the 12 Lead Electrocardiogram","authors":"M. Jennings, A. Rababah, Daniel Güldenring, J. Mclaughlin, D. Finlay","doi":"10.23919/cinc53138.2021.9662649","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662649","url":null,"abstract":"Background: There are limited datasets available to facilitate the evaluation of patch-based lead systems, so the leads must be derived from existing data, mainly the 12-lead ECG. We have previously introduced a short spaced lead (SSL) system consisting of two leads with the largest ST segment changes during ischaemic-type episodes. In this study, we aim to evaluate the derivation of this patch-based lead system from the 12-lead ECG. Method: Thoracic body surface potential maps (BSPM) were recorded from $n=734$ patients. Using Laplacian interpolation, each recording was expanded to the 352-node Dalhousie torso. The eight independent channels of the 12-lead ECG were extracted (I, II, V1-V6) with the two leads of the SSL patch Coefficients were derived using linear regression from the 12-lead ECG to the SSL patch. Results: The median Pearson correlation coefficients (CC) and root mean square error (RMSE) for each lead were calculated as follows (CC/RMSE): $0.986/74.3 mu V$ (ST monitoring lead); $0.976/65.3 mu V$ (spatially orthogonal lead). Conclusion: We have developed coefficients that allow the derivation of a patch-based lead system from the 12-lead ECG. Given the high correlation, it is possible to generate short spaced lead systems from existing diagnostic lead systems, however, amplitude errors are introduced in the process.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132070980","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":"Repolarization Gradients Alter Post-infarct Ventricular Tachycardia Dynamics in Patient-Specific Computational Heart Models","authors":"E. Sung, A. Prakosa, N. Trayanova","doi":"10.23919/cinc53138.2021.9662786","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662786","url":null,"abstract":"Repolarization heterogeneity contributes to ventricular tachycardia (VT) arrhythmogenesis but the impact of repolarization gradients on post-infarct VT dynamics is not well-characterized. The goal of our study is to assess the effects of repolarization gradients on post-infarct VT dynamics using patient-specific heart models. Baseline models were reconstructed along with the patient-specific scar and infarct border zone from imaging. Models with action potential duration (APD) gradients along apicobasal (AB) and transmural (TM) axes were also reconstructed. Rapid pacing was used to induce VTs. The resultant VT dynamics (inducibility, re-entry pathway, and the exit site) were assessed. Repolarization gradients did not impact VT inducibility but did alter both the reentry pathway and exit site location due to modulations in unidirectional conduction block. Both AB and TM APD gradients alone were also sufficient for inducing these changes in VT dynamics. Lastly, APD gradients revealed multiple distinct morphologies that used similar conducting channels in the patient-specific substrate. These results highlight how the interplay between repolarization gradients and the patient-specific substrate can have consequences on post-infarct VT dynamics.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"306 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123047309","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}
J. Elliott, M. Belen, L. Mainardi, V. Corino, J. F. R. Matas
{"title":"Impacts of Cellular Electrophysiological Variability on Conduction Velocity Within Isolated Tissue and Depolarization and Repolarization Across the Whole Atrial Model","authors":"J. Elliott, M. Belen, L. Mainardi, V. Corino, J. F. R. Matas","doi":"10.23919/cinc53138.2021.9662770","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662770","url":null,"abstract":"Improved understanding of the impact of variability on electrophysiological mechanisms is key to understanding the cause and development of cardiovascular disease. Recent studies suggest cellular variability could have an impact on electrophysiological behavior that homogeneous models are unable to capture. This study investigates the impact of cellular variability on conduction velocity and the depolarization and repolarization phases of the atria. Method: 10 Isolated tissue samples for each atrial region were calibrated for CV and later combined in a detailed anatomical atrial model. Variable models were compared with equivalent homogeneous models. Activation maps and APD maps were used for comparison. Results: In isolated tissue simulations, differences in tissue conductance (Gi) ranged between 5.5% reduction to 5.4% increase as a result of heterogeneity, despite differences in CV being <1%. Activation maps showed no significant differences between regionally homogeneous and heterogeneous atrial models. Repolarization across the atria differed significantly between regionally homogeneous and heterogeneous atrial models. Conclusion: Cellular variability has no significant impact on depolarization but significantly influences atrial repolarization. This could result in increased susceptibility to re-entries and atrial fibrillation.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124457370","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":"Towards Generalization of Cardiac Abnormality Classification Using ECG Signal","authors":"Xiaoyu Li, Chen Li, Xian Xu, Yuhua Wei, Jishang Wei, Yuyao Sun, B. Qian, Xiao Xu","doi":"10.23919/cinc53138.2021.9662822","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662822","url":null,"abstract":"In the PhysioNet/Computing in Cardiology Challenge 2021, our team, DrCubic, develops a novel approach to classify cardiac abnormalities using reduced-lead ECG recordings. In our approach, we incorporate peak detection as a self-supervised auxiliary task. We build the model based on SE-ResNet, and integrate models of different input lengths and sampling rates. Inspired by last year's challenge results, we investigate various settings and techniques, and select the best ones, considering the intra-source performance and inter-source generalization simultaneously. Our classifiers receive scores of 0.49, 0.50, 0.50, 0.51, and 0.48 (ranked 9th, 8th, 7th, 5th, and 9th out of 39 scored teams) for the 12 -lead, 6-lead, 4-lead, 3-lead, and 2 -lead versions of the hidden test sets with the Challenge evaluation metric.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128992671","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}
Narimane Gassa, Benjamin Sacristan, N. Zemzemi, M. Laborde, Juan Garrido Oliver, Clara Matencio Perabla, G. Jiménez-Pérez, O. Camara, S. Ploux, M. Strik, P. Bordachar, R. Dubois
{"title":"Benchmark of deep learning algorithms for the automatic screening in electrocardiograms transmitted by implantable cardiac devices","authors":"Narimane Gassa, Benjamin Sacristan, N. Zemzemi, M. Laborde, Juan Garrido Oliver, Clara Matencio Perabla, G. Jiménez-Pérez, O. Camara, S. Ploux, M. Strik, P. Bordachar, R. Dubois","doi":"10.23919/cinc53138.2021.9662651","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662651","url":null,"abstract":"The objective of this work was to benchmark different deep learning architectures for noise detection against cardiac arrhythmia episodes recorded by pacemakers and implantable cardioverter-defibrillators (PM/ICDs) and transmitted for remote monitoring. Up to now, most signal processing from ICD data has been based on classical hand-crafted algorithms, not AI or DL-based ones. The database consist of PM/ICD data from 805 patients representing a total of 10471 recordings from three different channels: the right ventricular (RV), the right atria (RA), and the shock channel. Four deep learning approaches were trained and optimized to classify PM/ICDs' records as actual ventricular signal vs noise episodes. We evaluated the performance of the different models using the F2 score. Results show that the use of 2D representations of 1D signals led to better performances than the direct use of 1D signals, suggesting that the detection of noise takes advantage of a spectral decomposition of the signal, which remains to be confirmed in other contexts. This study proposes deep learning approaches for the analysis of remote monitoring recordings from PM/ICDs. The detection of noise allows efficient management of this large daily flow of data.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129154275","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}
M. Hansen, B. Grønfeldt, Tue Rømer, Mathilde Fogelstrøm, Kasper Sørensen, S. Schmidt, J. Helge
{"title":"Determination of Maximal Oxygen Uptake Using Seismocardiography at Rest","authors":"M. Hansen, B. Grønfeldt, Tue Rømer, Mathilde Fogelstrøm, Kasper Sørensen, S. Schmidt, J. Helge","doi":"10.23919/cinc53138.2021.9662756","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662756","url":null,"abstract":"Introduction: Assessment of maximal oxygen consumption (VO<inf>2</inf>max) is an important clinical tool when examining both healthy and unhealthy populations, as a low VO<inf>2</inf>max is associated with cardiovascular disease and all-cause mortality. Aim: This study investigated the accuracy of a non-exercise test for assessment of VO<inf>2</inf>max using seismocardiography (SCG). Methods: 97 participants (20–45 years, 50 males) underwent a nonexercise test using SCG at rest in the supine position (SCG VO<inf>2</inf>max) and a graded exercise test to voluntary exhaustion on a cycle ergometer with indirect calorimetry (IC VO<inf>2</inf>max). An interim analysis was applied after 50 participants had completed testing (SCG VO<inf>2</inf>max 1.0) allowing for the algorithm to be modified (SCG VO<inf>2</inf>max 2.1). Results: SCG VO<inf>2</inf>max 2.1 (<tex>$n=47$</tex>, test set) estimation was <tex>$3.5 pm 1.8 mlcdot min^{-1}cdot kg^{-1} (p < 0.001)$</tex> lower compared to IC VO<inf>2</inf>max, with a Pearson correlation of <tex>$r=0.65 (p < 0.0001)$</tex> and a standard error of estimate of 7.1 ml·min<sup>−1</sup> ·kg<sup>−1</sup>. The coefficient of variation between tests was <tex>$8 pm 1%$</tex>. Conclusion: The accuracy of VO<inf>2</inf>max assessment using SCG requires further optimization prior to clinical application, as SCG VO<inf>2</inf>max was systematically lower than IC VO<inf>2</inf>max, and only a moderate correlation together with considerable variation were observed between tests.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128834014","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}
Martin Schmidt, Filip Karisik, S. Zaunseder, A. Linke, H. Malberg, M. Baumert
{"title":"Evaluation of Ventricular Repolarization Variability in Patients With Nonischemic Dilated Cardiomyopathy From Vectorcardiography","authors":"Martin Schmidt, Filip Karisik, S. Zaunseder, A. Linke, H. Malberg, M. Baumert","doi":"10.23919/cinc53138.2021.9662932","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662932","url":null,"abstract":"To investigate the predictive value of Ventricular repo-larization variability (VRV) in patients with nonischemic dilated cardiomyopathy, we analyzed the Defibrillator in Non-Ischemic Cardiomyopathy Treatment Evaluation trial (DEFINITE). The Telemetric and Holter ECG Warehouse (THEW) data set E-HOL-03-0401-017 comprises 393 recordings from 236 patients. All patients had a left ventricular ejection fraction $< 36$ % and were randomized to receiving standard medical therapy with or without an ICD. 24h-Holter 3-lead (Frank lead system) ECGs were performed at enrollment and after up to 5 years' follow-up. The all-cause mortality during the follow-up period was 4.8 %. We analyzed three-dimensional variability of the T-loop and QT interval variability on a single lead basis by employing three-dimensional signals adaptation and two-dimensional signal warping, respectively, to quantify VRV. To assess the predictive value of VRV parameters, Kaplan-Meier survival curves of baseline Holter ECGs were calculated. Our results showed significant association to survival ( $P < 0.01$ by the log-rank test) for T wave amplitude corrected QT interval variability index (cQTVi) on single lead basis. Low cQTVi group showed no mortality for the entire observation period. We found no associations between cQTVi groups and patient-specific parameters.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128581088","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":"Advances in ECG-Based Cardiac Ischemia Monitoring - A Review","authors":"John Wang","doi":"10.23919/cinc53138.2021.9662691","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662691","url":null,"abstract":"Real-time ST-segment monitoring for ischemia detection was introduced for clinical use in the 80s. To overcome the earlier systems' limitation on the number of leads monitored, systems that support continuous 12-lead ECG acquisition were developed. Derived 12-lead ECGs from 5-wire and 6-wire lead sets were also developed when direct 12 -lead acquisition was not practical. Several innovative graphical solutions were developed to manage the large amount of date from continuous 12-lead ST monitoring, including ST Map for better visual tracking of ST measurements, STEMI Map for more accurate tracking of STEMI criteria, and ST Topology for more efficient ST trending review. To further improve the accuracy of acute ischemia/infraction detection, two advanced 12-lead based lead derivation methods are being developed. The vessel-specific leads (VSLs) method measures ST elevation from three optimal leads, calculated from the 12-lead ECG, for detecting ST-segment deviation during coronary occlusion. The computed electrocardiographic imaging (CEI) method presents a bulls-eye polar plot of the heart surface potentials based on inverse calculation from the body-surface potential mapping derived from the 12-lead ECG. Early results show that these methods could be a useful clinical decision support tool for improving the accuracy of ECG-based triage of chest-pain patients.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116410044","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. Krivenko, A. Pulavskyi, L. Kryvenko, O. Krylova, Sergey A. Krivenko
{"title":"Using Mel-Frequency Cepstrum and Amplitude-Time Heart Variability as XGBoost Handcrafted Features for Heart Disease Detection","authors":"S. Krivenko, A. Pulavskyi, L. Kryvenko, O. Krylova, Sergey A. Krivenko","doi":"10.23919/cinc53138.2021.9662929","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662929","url":null,"abstract":"We have developed the XGBoost model to identify 27 heart pathologies within the challenge Will Two Do? Varying Dimensions in Electrocardiography: The PhysioNet/ Computing in Cardiology Challenge 2021. The technical part included several stages. At the first stage, the ECG was cut off to 10 seconds. At the second stage, resampling to frequencies 125 and 500 Hz was carried out and filtering in the 0.5-45 Hz bands. At the third stage, the features of HRV and symbolic dynamics were extracted from the signal with a sampling rate of 125 Hz. The melspectrograms were calculated based on a signal with a sampling frequency of 500 Hz. Then the features calculated for each lead were concatenated to obtain the final vector of features. We were faced with the task of constructing 27 independent binary classifiers, each of which defines a certain pathology. The fourth important step was to build balanced datasets for the algorithm. For the robustness of the models, the control groups for each contained almost all pathologies presented in the databases, except target disease. Our team Sunset scored 0.22, 0.21, 0.22, 0.21, 0.20 for the 12-lead, 6-lead, 4-lead, 3-lead, and 2-lead models, respectively, ranking 32 out of 39 teams for the first four lead combinations and 31 out of 39 teams for the last.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116756399","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}
K. Čurila, P. Jurák, P. Leinveber, R. Smíšek, P. Stros, F. Plesinger, I. Viscor, V. Vondra, J. Mizner, O. Sussenbek, L. Znojilova, J. Karch, M. Susankova, J. Halámek, F. Prinzen
{"title":"Physiological versus non-physiological cardiac pacing as assessed by Ultra-high-frequency electrocardiography","authors":"K. Čurila, P. Jurák, P. Leinveber, R. Smíšek, P. Stros, F. Plesinger, I. Viscor, V. Vondra, J. Mizner, O. Sussenbek, L. Znojilova, J. Karch, M. Susankova, J. Halámek, F. Prinzen","doi":"10.23919/cinc53138.2021.9662912","DOIUrl":"https://doi.org/10.23919/cinc53138.2021.9662912","url":null,"abstract":"Background: Permanent cardiac pacing can cause heart failure, with the ventricular dyssynchrony being identified as the main cause for its development. Method: His bundle pacing (HBp), left bundle branch pacing (LBBp), and left ventricular myocardial septal pacing (LVSP) were introduced recently. Their impact on ventricular dyssynchrony was not known. We used ultra-high-frequency ECG (UHF-ECG) to compare ventricular depolarization in these pacing techniques. Results: We showed the nonselective HB pacing produces the same pattern of UHF-ECG ventricular depolarization as selective HB pacing. Next, we showed the nonselective His bundle pacing in the area below the tricuspid valve has the best interventricular synchrony from all other RV pacing locations with myocardial capture. We also compared UHF-ECG-derived parameters of ventricular depolarization during HBp, LBBp, and LVSP and we showed that both pacing types from the left septal area are less physiological than nsHBp. Conclusion: UHF-ECG is an effective tool that can be used in clinical practice to assess the electrical dyssynchrony caused by cardiac pacing. Furthermore, its real-time implementation allows recognizing between physiological vs. non-physiological pacing during an implant procedure.","PeriodicalId":126746,"journal":{"name":"2021 Computing in Cardiology (CinC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116813580","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}