Computing in cardiology最新文献_第3页

Using UncertainSCI to Quantify Uncertainty in Cardiac Simulations. 用不确定性sci量化心脏模拟中的不确定性。

Computing in cardiology Pub Date : 2020-09-01 DOI: 10.22489/cinc.2020.275

Lindsay C Rupp, Zexin Liu, Jake A Bergquist, Sumientra Rampersad, Dan White, Jess D Tate, Dana H Brooks, Akil Narayan, Rob S MacLeod

{"title":"Using UncertainSCI to Quantify Uncertainty in Cardiac Simulations.","authors":"Lindsay C Rupp, Zexin Liu, Jake A Bergquist, Sumientra Rampersad, Dan White, Jess D Tate, Dana H Brooks, Akil Narayan, Rob S MacLeod","doi":"10.22489/cinc.2020.275","DOIUrl":"https://doi.org/10.22489/cinc.2020.275","url":null,"abstract":"Cardiac simulations have become increasingly accurate at representing physiological processes. However, simulations often fail to capture the impact of parameter uncertainty in predictions. Uncertainty quantification (UQ) is a set of techniques that captures variability in simulation output based on model assumptions. Although many UQ methods exist, practical implementation can be challenging. We created UncertainSCI, a UQ framework that uses polynomial chaos (PC) expansion to model the forward stochastic error in simulations parameterized with random variables. UncertainSCI uses non-intrusive methods that parsimoniously explores parameter space. The result is an efficient, stable, and accurate PC emulator that can be analyzed to compute output statistics. We created a Python API to run UncertainSCI, minimizing user inputs needed to guide the UQ process. We have implemented UncertainSCI to: (1) quantify the sensitivity of computed torso potentials using the boundary element method to uncertainty in the heart position, and (2) quantify the sensitivity of computed torso potentials using the finite element method to uncertainty in the conductivities of biological tissues. With UncertainSCI, it is possible to evaluate the robustness of simulations to parameter uncertainty and establish realistic expectations on the accuracy of the model results and the clinical guidance they can provide.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":"47 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9956381/pdf/nihms-1836950.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9407481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Reconstructing Cardiac Wave Dynamics From Myocardial Motion Data. 从心肌运动数据重构心波动力学。

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/CinC.2020.216

Christopher B Beam, Cristian A Linte, Niels F Otani

{"title":"Reconstructing Cardiac Wave Dynamics From Myocardial Motion Data.","authors":"Christopher B Beam, Cristian A Linte, Niels F Otani","doi":"10.22489/CinC.2020.216","DOIUrl":"https://doi.org/10.22489/CinC.2020.216","url":null,"abstract":"Various models exist to predict the active stresses and membrane potentials within cardiac muscle tissue. However, there exist no methods to reliably measure active stresses, nor do there exist ways to measure transmural membrane potentials that are suitable for in vivo usage. Prior work has devised a linear model to map from the active stresses within the tissue to displacements [1]. In situations where measurements of tissue displacements are entirely precise, we are able to naively solve for the active stresses from the measurements with ease. However, real measurement processes always carry some associated random error and, in the presence of this error, our naive solution to this inverse problem fails. In this work we propose the use of the Ensemble Transform Kalman Filter to more reliably solve this inverse problem. This technique is faster than other related Kalman Filter techniques while still generating high quality estimates which improve on our naive solution. We demonstrate, using in silico simulations, that the Ensemble Transform Kalman Filter produces errors whose standard deviation is an order of magnitude smaller than the least-squares solution.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8159184/pdf/nihms-1705227.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39035099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Deep Learning Based Prediction of Atrial Fibrillation Disease Progression with Endocardial Electrograms in a Canine Model. 基于深度学习的犬模型心内膜电图房颤疾病进展预测。

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/cinc.2020.291

Bram Hunt, Eugene Kwan, Mark McMillan, Derek Dosdall, Rob MacLeod, Ravi Ranjan

{"title":"Deep Learning Based Prediction of Atrial Fibrillation Disease Progression with Endocardial Electrograms in a Canine Model.","authors":"Bram Hunt, Eugene Kwan, Mark McMillan, Derek Dosdall, Rob MacLeod, Ravi Ranjan","doi":"10.22489/cinc.2020.291","DOIUrl":"https://doi.org/10.22489/cinc.2020.291","url":null,"abstract":"Objective: We sought to determine whether electrical patterns in endocardial wavefronts contained elements specific to atrial fibrillation (AF) disease progression.Methods: A canine paced model (n=7, female mongrel, 29±2 kg) of persistent AF was endocardially mapped with a 64-electrode basket catheter during periods of AF at 1 month, 3 month, and 6 months post-implant of stimulator. A 50-layer residual network was then trained to map half-second electrogram samples to their source timepoint.Results: The trained network achieved final validation and testing accuracies of 51.6 and 48.5% respectively. Per class F1 scores were 24%, 59%, and 53% for 1 month, 3 month, and 6 month inputs from the testing dataset.Conclusion: Differentiation of AF based on its time progression was shown to be feasible with a deep learning method. This is promising for differentiating treatment based on disease progression though low accuracy with earlier timepoints may be an obstacle to identifying nascent AF.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8286069/pdf/nihms-1722621.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39198138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Quantifying the Spatiotemporal Influence of Acute Myocardial Ischemia on Volumetric Conduction Speeds. 量化急性心肌缺血对容量传导速度的时空影响。

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/cinc.2020.279

Wilson W Good, Brian Zenger, Jake A Bergquist, Lindsay C Rupp, Karli Gillette, Gernot Plank, Rob S MacLeod

{"title":"Quantifying the Spatiotemporal Influence of Acute Myocardial Ischemia on Volumetric Conduction Speeds.","authors":"Wilson W Good, Brian Zenger, Jake A Bergquist, Lindsay C Rupp, Karli Gillette, Gernot Plank, Rob S MacLeod","doi":"10.22489/cinc.2020.279","DOIUrl":"https://doi.org/10.22489/cinc.2020.279","url":null,"abstract":"Acute myocardial ischemia compromises the ordered electrical activation of the heart, however, because of sampling limitations, volumetric changes in activation have not been measured. We used a large-animal experimental model and high-resolution volumetric mapping to study the effects of ischemia on conduction speeds (CS) throughout the myocardium. We estimated CS and electrocardiographic changes (ST segments) and evaluated the spatial and temporal correlations between them across 11 controlled episodes. We found that ischemia induces significant conduction slowing, reducing the global median speed by 25 cm/s. Furthermore, there was a high temporal correlation between the development of ischemic severity and CS (corr. = 0.93) through each episode. The spatial correlations between ST-segment changes and CS slowing were more spatially complex than expected with substantial slowing at the periphery of the zones that showed ST-segment changes. This is the first study that has documented in an experimental model volumetric changes of CS during acute myocardial ischemia and explored the relationships between ischemia development in space and time. We showed that conduction speed changes are spatiotemporally correlated to ischemic severity and illustrated the biphasic response long proposed from cellular studies.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8082333/pdf/nihms-1695017.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38950938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Experimental Validation of a Novel Extracellular-Based Source Representation of Acute Myocardial Ischemia. 一种新的基于细胞外的急性心肌缺血源表征的实验验证。

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/cinc.2020.190

Brian Zenger, Jake A Bergquist, Wilson W Good, Lindsay C Rupp, Rob S MacLeod

{"title":"Experimental Validation of a Novel Extracellular-Based Source Representation of Acute Myocardial Ischemia.","authors":"Brian Zenger, Jake A Bergquist, Wilson W Good, Lindsay C Rupp, Rob S MacLeod","doi":"10.22489/cinc.2020.190","DOIUrl":"https://doi.org/10.22489/cinc.2020.190","url":null,"abstract":"Electrocardiographic imaging (ECGI) based detection of myocardial ischemia requires an accurate formulation of the source model, which includes a relationship between extracellular and transmembrane potentials (TMPs). In this study, we used high-resolution intramural experimental recordings and forward modeling to examine the relationship between extracellular potentials and TMPs during myocardial ischemia. We measured extracellular electro-grams from intramural plunge needle arrays during seven controlled ischemia episodes in an animal model. We used three TMP source representations: (1) parameterized and distance-based (defined previously), (2) extracellular-based linear transform, and (3) extracellular-based sigmoidal transform. TMPs for each source formulation were then used to compute extracellular potentials by calculating the passive bidomain forward solution throughout the myocardium. We compared measured and computed potentials. Linear and sigmoidal approaches produced improved results compared to the parameterized method. The RMSE, SC, and TC of linear, sigmoidal, and parameterized methods were 0.85 mV, 1.21 mV, and 3.37 mV; 0.91, 0.88, and 0.47; 0.90, 0.77, and 0.33 respectively. We found extracellular-based calculations of TMPs produced superior forward computations compared to parameterized zones.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8084598/pdf/nihms-1695009.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38950939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Image-based Approach for 3D Left Atrium Functional Measurements. 基于图像的三维左心房功能测量方法。

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/cinc.2020.459

Alan Morris, Eugene Kholmovski, Nassir Marrouche, Joshua Cates, Shireen Elhabian

引用次数: 2

Novel Experimental Preparation to Assess Electrocardiographic Imaging Reconstruction Techniques. 评估心电图成像重构技术的新型实验准备。

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/cinc.2020.458

Jake A Bergquist, Brian Zenger, Wilson W Good, Lindsay C Rupp, Laura R Bear, Rob S MacLeod

{"title":"Novel Experimental Preparation to Assess Electrocardiographic Imaging Reconstruction Techniques.","authors":"Jake A Bergquist, Brian Zenger, Wilson W Good, Lindsay C Rupp, Laura R Bear, Rob S MacLeod","doi":"10.22489/cinc.2020.458","DOIUrl":"10.22489/cinc.2020.458","url":null,"abstract":"Electrocardiographic imaging (ECGI) systems are still plagued by a myriad of controllable and uncontrollable sources of error, which makes studying and improving these systems difficult. To mitigate these errors, we developed a novel experimental preparation using a rigid pericardiac cage suspended in a torso-shaped electrolytic tank. The 256-electrode cage was designed to record signals 0.5-1.0 cm above the entire epicardial surface of an isolated heart. The cage and heart were fixed in a 192-electrode torso tank filled with electrolyte with predetermined conductivity. The resulting signals served as ground truth for ECGI performed using the boundary element method (BEM) and method of fundamental solutions (MFS) with three regularization techniques: Tikhonov zero-order (Tik0), Tikhonov second-order (Tik2), truncated singular value decomposition (TSVD). Each ECGI regularization technique reconstructed cage potentials from recorded torso potentials well with spatial correlation above 0.7, temporal correlation above 0.8, and root mean squared error values below 0.7 mV. The earliest site of activation was best identified by MFS using Tik0, which localized it to within a range of 1.9 and 4.8 cm. Our novel experimental preparation has shown unprecedented agreement with simulations and represents a new standard for ECGI validation studies.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8082331/pdf/nihms-1695016.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38941199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Personalized Low-Energy Defibrillation Through Feedback Based Resynchronization Therapy. 通过基于反馈的再同步疗法实现个性化低能量除颤。

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/cinc.2020.471

Ilija Uzelac, Flavio H Fenton

{"title":"Personalized Low-Energy Defibrillation Through Feedback Based Resynchronization Therapy.","authors":"Ilija Uzelac, Flavio H Fenton","doi":"10.22489/cinc.2020.471","DOIUrl":"10.22489/cinc.2020.471","url":null,"abstract":"Aims: Defibrillation shocks may cause AV node burnout, scar formation, and pain. In this study, we present a real-time feedback-based control of ventricular fibrillation (VF) with a series of low-energy shocks using ventricular electrical activity as the feedback input.Methods: Isolated rabbit hearts were Langendorff perfused and stained with a fluorescent Vm dye. The ventricular activity was measured with a pair of photodiodes, and processed with a feedback controller to calculate defibrillation shock parameters in real-time. Shock timing was based on desynchronized activation of the left and right ventricles during VF, and the strength was proportional to the amplitude difference of the photodiode signals. Shocks were delivered with a custom-developed arbitrary waveform trans-conductance amplifier.Results: Feedback based resynchronization therapy converts VT to MT before sinus rhythm is restored with a reduction of defibrillation energy, compared to a single biphasic shock.Conclusions: Feedback based resynchronization therapy is based on real-time sensing of ventricular activity, while a series of low-energy shocks are delivered, reducing the risk of associated side effects.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":"2020 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8378784/pdf/nihms-1703417.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39335329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development, Implementation and Testing of a Multicellular Dynamic Action Potential Clamp Simulator for Drug Cardiac Safety Assessment. 用于药物心脏安全性评估的多细胞动态动作电位钳模拟器的开发、实施和测试。

Computing in cardiology Pub Date : 2020-09-01 DOI: 10.22489/CinC.2020.416

Maria Camporesi, Chiara Bartolucci, Chon Lok Lei, Gary R Mirams, Teun P de Boer, Stefano Severi

引用次数: 0

Right Ventricular Shape Distortion in Tricuspid Regurgitation. 三尖瓣反流的右心室形状变形

Computing in cardiology Pub Date : 2020-09-01 Epub Date: 2021-02-10 DOI: 10.22489/cinc.2020.346

Ashley E Morgan, Atefeh Kashani, Brian Zenger, Lindsay C Rupp, Maura D Perez, Markus D Foote, Alan K Morris, Mark B Ratcliffe, Jiwon J Kim, Jonathan W Weinsaft, Vikas Sharma, Rob S MacLeod, Shireen Elhabian

{"title":"Right Ventricular Shape Distortion in Tricuspid Regurgitation.","authors":"Ashley E Morgan, Atefeh Kashani, Brian Zenger, Lindsay C Rupp, Maura D Perez, Markus D Foote, Alan K Morris, Mark B Ratcliffe, Jiwon J Kim, Jonathan W Weinsaft, Vikas Sharma, Rob S MacLeod, Shireen Elhabian","doi":"10.22489/cinc.2020.346","DOIUrl":"10.22489/cinc.2020.346","url":null,"abstract":"Tricuspid regurgitation (TR) is a failure in right-sided AV valve function which, if left untreated, leads to marked cardiac shape changes and heart failure. However, the specific right ventricular shape changes resulting from TR are unknown. The goal of this study is to characterize the RV shape changes of patients with severe TR. RVs were segmented from CINE MRI images. Using particle-based shape modeling (PSM), a dense set of homologous landmarks were placed with geometric consistency on the endocardial surface of each RV, via an entropy-based optimization of the information content of the shape model. Principal component analysis (PCA) identified the significant modes of shape variation across the population. These modes were used to create a patient-prediction model. 32 patients and 6 healthy controls were studied. The mean RV shape of TR patients demonstrated increased sphericity relative to controls, with the three most dominant modes of variation showing significant widening of the short axis of the heart, narrowing of the base at the RV outflow tract (RVOT), and blunting of the RV apex. By PCA, shape changes based on the first three modes of variation correctly identified patient vs. control hearts 86.5% of the time. The shape variation may further illuminate the mechanics of TR-induced RV failure and recovery, providing potential targets for therapies including novel devices and surgical interventions.","PeriodicalId":72683,"journal":{"name":"Computing in cardiology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7992117/pdf/nihms-1677201.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25540037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0