2015 Computing in Cardiology Conference (CinC)最新文献_第2页

Parameter estimation of a mathematical model describing the cardiovascular-respiratory interaction 描述心血管-呼吸相互作用的数学模型的参数估计

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-06 DOI: 10.1109/CIC.2015.7410986

Layli S. Goldoozian, A. Hidalgo-Muñoz, V. Zarzoso, E. Zahedi

{"title":"Parameter estimation of a mathematical model describing the cardiovascular-respiratory interaction","authors":"Layli S. Goldoozian, A. Hidalgo-Muñoz, V. Zarzoso, E. Zahedi","doi":"10.1109/CIC.2015.7410986","DOIUrl":"https://doi.org/10.1109/CIC.2015.7410986","url":null,"abstract":"Short-term interaction between heart rate (HR) and physiological measures like blood pressure and respiration reveals relevant information about autonomic nervous system (ANS) function. Complex mathematical models for describing their couplings have been proposed in the literature. However, an accurate estimation of their parameters in an inverse modeling problem is crucial to extract reliable ANS related indices. This study considers a physiologically-based model of the cardiovascular-respiratory system and ANS control that presents the neural and mechanical effects of respiration separately. The estimation method is evaluated on synthetic signals. An accurate estimation of the highest-sensitivity model parameter (intrinsic HR) is achieved with an error of 4:7 ± 3:4% over the actual values. One of the parameters reflecting the amplitude of the respiratory-mediated variations presents an even better approximation with a mean relative error as low as 3:8±3:3%. Our results show that most of the high-sensitivity parameters and also respiratory-related parameters that are specifically considered in our physiologically-based framework can be well approximated regardless of their initial values.","PeriodicalId":414802,"journal":{"name":"2015 Computing in Cardiology Conference (CinC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130224423","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}

引用次数: 1

Robust framework for quantitative analysis of optical mapping signals without filtering 无滤波光学映射信号定量分析的鲁棒框架

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7408686

I. Uzelac, F. Fenton

{"title":"Robust framework for quantitative analysis of optical mapping signals without filtering","authors":"I. Uzelac, F. Fenton","doi":"10.1109/CIC.2015.7408686","DOIUrl":"https://doi.org/10.1109/CIC.2015.7408686","url":null,"abstract":"Experimental studies with in-vitro isolated hearts using optical mapping techniques have had a significant impact on our understanding of cardiac electrophysiology. The trans-membrane voltage Vm, and intracellular free calcium concentration [Cai]+2 signals obtained from optical mapping experiments can often be corrupted with noise. This is mostly due to the small light intensities and very short exposure times when high speed cameras are used at frames rates of 500-1000 fps. In addition, for small preparations or recordings of small areas, the noise floor levels are even greater and can be comparable to the amplitude of the signal (S/N ≈1). In general strong spatial and temporal filtering is necessary to remove the noise at the expenses of signal degradation and loss of critical information especially at high frequencies that are of a particular interest. In this paper we present and analyze an oversampling image processing technique where due to the cycling processes in cardiac activity during steady state dynamics we are able to stack (sum up) the images recorded at specific equidistant time intervals. The stacking process reduces the noise effectively as the square root of the number of stacked images used. We show that no spatial or temporal filtering is needed to obtain useful data with the stacking technique that allows us to resolve information on a time scale only limited with a sampling rate.","PeriodicalId":414802,"journal":{"name":"2015 Computing in Cardiology Conference (CinC)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115145623","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}

引用次数: 15

Automatic detection of atrial fibrillation using MEMS accelerometer 基于MEMS加速度计的房颤自动检测

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7411039

T. Koivisto, Mikko Pänkäälä, Tero Hurnanen, T. Vasankari, T. Kiviniemi, A. Saraste, J. Airaksinen

引用次数: 16

Autonomic nervous system assessment in critically ill patients undergoing a cognitive rehabilitation therapy 危重患者接受认知康复治疗的自主神经系统评估

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7411028

D. Hernando, M. Turón, R. Bailón, S. Fernández-Gonzalo, J. Lázaro, G. Gomà, E. Gil, J. Montanyà, J. López-Aguilar, C. D. Haro, P. Laguna, L. Blanch

引用次数: 1

Mental stress assessment - a comparison between HRV based and respiration based techniques 精神压力评估-基于HRV和基于呼吸的技术之间的比较

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7411089

Shreyansh Gandhi, M. Baghini, S. Mukherji

引用次数: 10

Load-dependency in mechanical properties of subepicardial and subendocardial cardiomyocytes 心外膜下和心内膜下心肌细胞力学特性的负荷依赖性

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7411073

A. Khokhlova, G. Iribe, O. Solovyova

{"title":"Load-dependency in mechanical properties of subepicardial and subendocardial cardiomyocytes","authors":"A. Khokhlova, G. Iribe, O. Solovyova","doi":"10.1109/CIC.2015.7411073","DOIUrl":"https://doi.org/10.1109/CIC.2015.7411073","url":null,"abstract":"Electrical and mechanical properties of myocardium vary transmurally in the left ventricular wall. Regional differences in the mechanical environment of cardiomyocytes may potentially contribute to this heterogeneity due to mechano-electric feedback. In the present study, we investigate transmural differences in active and passive tensions at different preloads between the subepicardial (EPI) and subendocardial (ENDO) cells isolated from mouse left ventricle, using our recently developed single cell stretch method where each cell end was held by a pair of carbon fibers to apply various extent of preload to the cells. To predict underlying mechanisms of the transmural differences, we used our electromechanical EPI and ENDO cell models to simulate experimentally obtained results. Wet experiments showed that both passive and active tensions at different preloads are higher in ENDO cardiomyocytes, indicating higher stiffness and contractility in ENDO cells compared to EPI cells. Our mathematical models reproduce experimental results, suggesting differences in the kinetics of cross bridges and calcium-troponin C complexes in ENDO and EPI models may essentially contribute to the differences in mechanical properties between the cells.","PeriodicalId":414802,"journal":{"name":"2015 Computing in Cardiology Conference (CinC)","volume":"2249 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127471834","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}

引用次数: 3

Drug toxicity on cardiac pacemaking: A multi-scale modelling study 药物对心脏起搏的毒性:一项多尺度模型研究

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7408608

Xiangyun Bai, Henggui Zhang, Kuanquan Wang, Yongfeng Yuan, Qince Li, Na Zhao

{"title":"Drug toxicity on cardiac pacemaking: A multi-scale modelling study","authors":"Xiangyun Bai, Henggui Zhang, Kuanquan Wang, Yongfeng Yuan, Qince Li, Na Zhao","doi":"10.1109/CIC.2015.7408608","DOIUrl":"https://doi.org/10.1109/CIC.2015.7408608","url":null,"abstract":"Drugs, such as cisapride, have to be withdrawn from clinical uses due to their side effects, i.e., cardiotoxicity. As an agonist, it can activate 5-Hydroxytryptamine 4 (5-HT4) receptors which are localized in sinoatrial node (SAN) and atrium. Our goal was to investigate the actions of cisapride alone and its combined effects with 5-HT4 receptors that impair cardiac pacemaking action potentials (APs) and their conduction using multi-scale models (the Zhang et al. models of APs of rabbit SAN cells and an anatomically detailed 2-D model of the intact SAN-atrium tissue models). At single cell level, the action of cisapride on IKr had positive chronotropic effect in the central SAN cell, but had virtually no effect on the peripheral cell. When its activation to 5-HT4 receptors was also considered, cisapride increased the pacing rate (PR) in centre SAN cell; but decreased it substantially in the periphery SAN cell. At the tissue level of the intact SAN-atrium, cisapride increased the PR and amplified the tachycardia effect of 5-HT4 receptor activation. It altered the activation sequence of cardiac excitation waves and reduced the maximum up-stroke velocity of the atrium. Moreover, early afterdepolarization was observed in the atrium. Our study shed light on the mechanisms of cisapride-induced arrhythmogenesis, suggesting that 5-HT4 receptors activation should be avoided in designing new anti-arrhythmic drugs.","PeriodicalId":414802,"journal":{"name":"2015 Computing in Cardiology Conference (CinC)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124777975","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}

引用次数: 0

Effect of interpolation on electroanatomical mapping 插值对电解剖成像的影响

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7408661

M. Sanromán-Junquera, Raquel Díaz-Valencia, A. García-Alberola, J. Rojo-álvarez, I. Mora-Jiménez

{"title":"Effect of interpolation on electroanatomical mapping","authors":"M. Sanromán-Junquera, Raquel Díaz-Valencia, A. García-Alberola, J. Rojo-álvarez, I. Mora-Jiménez","doi":"10.1109/CIC.2015.7408661","DOIUrl":"https://doi.org/10.1109/CIC.2015.7408661","url":null,"abstract":"Cardiac navigation systems (CNS) are often used in electrophysiological studies to create spatial-electrical maps supporting the arrhythmia mechanism identification. Sequentially recorded electrograms yield the bioelectrical information from features such as voltage and activation times in terms of their spatial location, which are subsequently interpolated for building the electroanatomical map (EAM) of the cardiac chamber. Our goal was to evaluate quantitatively the effect of interpolation in the EAM accuracy when reconstructed from a set of samples. Triangulated irregular networks (TIN), thin plate spline (TPS), and support vector machines (SVM) were assessed by using: (a) two detailed simulated time activation maps during flutter and sinus rhythm in both atria; (b) a set of real CNS maps, given by 13 activation time and 19 voltage maps, with 6 right atria (RA), 6 left atria (LA), 4 right ventricles (RV), and 16 left ventricles (LV). Interpolation methods were benchmarked using root mean squared error (RMSE), efficiency (EF), and Willmott distance (WD). On the one hand, EF and WD were similar for yielding a clearer cut-off point than RMSE for the number of required samples, which was about 100. Better EAM accuracy was obtained using TPS, followed by SVM and TIN, except for flutter in the RA, where early-meets-late was smoothed by SVM. On the other hand, EAM accuracy (in terms of the average WD) was slightly outperformed by RA than LA (0.57 vs 0.52), whereas RV and LV were similar (0.71 vs 0.71). In reference to the methods, similar average WD was given by the interpolation methods (TIN 0.64 ± 0.14; TPS 0.66 ± 0.15; SVM 0.65 ± 0.18). The EAM accuracy is dependent on the map nature and on the cardiac chamber.","PeriodicalId":414802,"journal":{"name":"2015 Computing in Cardiology Conference (CinC)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124950312","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}

引用次数: 3

A principal component analysis approach to heart rate turbulence assessment in Chagas disease 查加斯病心率湍流评估的主成分分析方法

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7411002

A. C. Alberto, G. A. Limeira, J. Nadal

{"title":"A principal component analysis approach to heart rate turbulence assessment in Chagas disease","authors":"A. C. Alberto, G. A. Limeira, J. Nadal","doi":"10.1109/CIC.2015.7411002","DOIUrl":"https://doi.org/10.1109/CIC.2015.7411002","url":null,"abstract":"The analysis of heart rate turbulence (HRT) is a powerful method to estimate the baroreflex from the 24 h Holter ECG signals, by considering that an isolated premature ventricular contraction (PVC) causes an immediate cardiac acceleration followed by a deceleration in normal subjects. This study aims at developing a method for risk stratification of sudden death in chronic Chagas cardiomyopathy, by applying Principal Component Analysis (PCA) to the averaged tachogram segments extracted for HRT analysis. HRT analysis was applied to a database of high resolution ECG from Chagas disease patients, with 10 min signals in three leads, sampled with 16-bit resolution at 1000 Hz. From a set of 115 records that presented premature ventricular contractions (PVC), it was possible to extract at least one valid tachogram for HRT analysis in just 51 signals. The valid segments from each ECG record were taken to compute a coherent mean, used them for measuring the parameters turbulence onset (TO) and turbulence slope (TS). From this dataset, two groups of eight signals were extract, according to the estimated risk of sudden death: high risk (TO ≥ 0 and TS ≤ 2,5 ms/RR interval) and low risk (TO > 0 and TS > 2,5 ms/RR interval). PCA was thus applied to this 16 coherent means of 19 samples to reduce data representation to three principal components (PC), which represented 99.5% of the original variance. Applied to the respective PC scores, a logistic regression allowed the separation of groups with 94% accuracy, 88% sensibility and 100% specificity. As a conclusion, PCA has a potential for baroreflex assessment throughout HRT in Chagas disease, but this method should be validated with a larger sample with long duration ECG.","PeriodicalId":414802,"journal":{"name":"2015 Computing in Cardiology Conference (CinC)","volume":"267 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126053466","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}

引用次数: 1

Multimodal data classification using signal quality indices and empirical similarity-based reasoning 基于信号质量指标和经验相似度推理的多模态数据分类

2015 Computing in Cardiology Conference (CinC) Pub Date : 2015-09-01 DOI: 10.1109/CIC.2015.7411131

Man Xu, Jiang Shen, Haiyan Yu

{"title":"Multimodal data classification using signal quality indices and empirical similarity-based reasoning","authors":"Man Xu, Jiang Shen, Haiyan Yu","doi":"10.1109/CIC.2015.7411131","DOIUrl":"https://doi.org/10.1109/CIC.2015.7411131","url":null,"abstract":"All bedside monitors are prone to heterogeneity and mis-labeled data, yet each multimodal sample data contains different sets of multi-dimensional attributes. To reduce the incidence of false alarms in the Intensive Care Unit (ICU), a new interactive classifier was proposed. In the algorithm, case was represented with signal quality Indices(SQIs) and RR interval features. With the function wabp, the annotations were obtained from the target signal after preprocessing. Five features were used as the inputs to a case-based reasoning classifier, retrieving the cases with empirical similarity. With the posted 750 records of the PhysioNet/CinC 2015 Challenge, the classifier was trained for answering the alarm types of the query segments. Compared with conventional threshold-based alarm algorithms, the performance of our proposed algthom reduces the maximum number of false alarms while avoiding the suppression of true alarms. Evaluated with the hidden test dataset, both real-time and retrospective, the results show that the overall TPR is 83% and 82% respectively; and TNR 44% and 43% respectively. This algorithm offers a new way of thinking about retrieving heterogeneity patients with multimodal data and classifying the alarm types in the context of mis-labeled cases.","PeriodicalId":414802,"journal":{"name":"2015 Computing in Cardiology Conference (CinC)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125531340","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}

引用次数: 2