Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745523
M. Vizcardo, J. Jiménez, F. Moleiro, A. Marcano, A. Octavio, A. Rodriguez
According to the World wide Organization of the Health, the number of people infected with the Tri-panosoma Cruzi is considered between 16 and 18 million, causal agent of the Chagaspsila disease, and in 100 million the people exposed to the affectation risk. When concluding in 1983 a study longitudinal epidemiologist in patients with the disease evaluated every 3 years, the cardiac affectation: chronic Chagasic myocarditis (MCHC) increased from a 17% at the beginning of the study to a 49, 4% after 15 years. Previous studies of the variability of cardiac frequency in patients with the Chagaspsila disease, show alterations in the spectral indices of the HRV. We analyze the 24-hour heart rate by Holter recordings in 62 patients with ECG alterations (CH2), 32 patients without ECG alterations (CH1) who had positive serological findings for disease of Chagaspsila and 36 healthy subjects (control) matched for sex and age. We find a orthogonal base that is able to discriminate the groups from circadian profiles, control and CH2, and stratify the groups CH1.
{"title":"Analysis of the heart rate variability and stratification of the risk of cardiac patients with Chagas’ disease","authors":"M. Vizcardo, J. Jiménez, F. Moleiro, A. Marcano, A. Octavio, A. Rodriguez","doi":"10.1109/CIC.2007.4745523","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745523","url":null,"abstract":"According to the World wide Organization of the Health, the number of people infected with the Tri-panosoma Cruzi is considered between 16 and 18 million, causal agent of the Chagaspsila disease, and in 100 million the people exposed to the affectation risk. When concluding in 1983 a study longitudinal epidemiologist in patients with the disease evaluated every 3 years, the cardiac affectation: chronic Chagasic myocarditis (MCHC) increased from a 17% at the beginning of the study to a 49, 4% after 15 years. Previous studies of the variability of cardiac frequency in patients with the Chagaspsila disease, show alterations in the spectral indices of the HRV. We analyze the 24-hour heart rate by Holter recordings in 62 patients with ECG alterations (CH2), 32 patients without ECG alterations (CH1) who had positive serological findings for disease of Chagaspsila and 36 healthy subjects (control) matched for sex and age. We find a orthogonal base that is able to discriminate the groups from circadian profiles, control and CH2, and stratify the groups CH1.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128119370","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745420
C. Bescos, M. Harris, R. Bover, R. Schmidt, J. Pérez-Villacastín
Chronic Heart Failure (CHF) is the major cause for hospitalization in adults in western societies, mainly due to decompensation of patients. Active prevention, diagnosis, and personalized treatment contribute to the stabilization of chronic patients and the reduction of events. The approach of the EU FP6 MyHeart project is to collect daily vital body signs on CHF patients in an easy and comfortable way. The data is processed via a decision support system (DSS) and the platform gives instant recommendations to the user. The system also sends the information to the professionals for a better follow-up. The designed DSS is based on Bayesian networks (BN) and combines the accepted standardized clinical guidelines with the most advanced monitoring data in daily routine, in order to provide individualized recommendations to the patient in a concrete situation.
{"title":"Decision support system for the practical implementation of the Chronic Heart Failure guidelines: The MyHeart approach","authors":"C. Bescos, M. Harris, R. Bover, R. Schmidt, J. Pérez-Villacastín","doi":"10.1109/CIC.2007.4745420","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745420","url":null,"abstract":"Chronic Heart Failure (CHF) is the major cause for hospitalization in adults in western societies, mainly due to decompensation of patients. Active prevention, diagnosis, and personalized treatment contribute to the stabilization of chronic patients and the reduction of events. The approach of the EU FP6 MyHeart project is to collect daily vital body signs on CHF patients in an easy and comfortable way. The data is processed via a decision support system (DSS) and the platform gives instant recommendations to the user. The system also sends the information to the professionals for a better follow-up. The designed DSS is based on Bayesian networks (BN) and combines the accepted standardized clinical guidelines with the most advanced monitoring data in daily routine, in order to provide individualized recommendations to the patient in a concrete situation.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128148150","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745511
E. Aramendi, U. Irusta, S. Ruiz de Gauna, J. Ruiz
In this study pediatric and adult Ventricular Tachycardia (VT) are used to test the efficiency of an AED analysis algorithm. Statistical assessment of the four significant parameters that define the shock-noshock classification algorithm has been performed. The following parameters are considered: Pulse Rate (PR), Waveform Power Ratio (WPR), and two morphological parameters, Baseline Content (BC) and Probability Distribution Width (PDW). A set of 76 adult and 55 pediatric shockable VT episodes is considered to measure the sensitivity of the classification algorithm originally developed for adult patients (100% for rapid adult VT). The sensitivity for the whole pediatric set is 96.36 %, but increases to 100% for the 1-8 years of age subgroup.
{"title":"Comparative analysis of the parameters affecting AED rhythm analysis algorithm applied to pediatric and adult Ventricular Tachycardia","authors":"E. Aramendi, U. Irusta, S. Ruiz de Gauna, J. Ruiz","doi":"10.1109/CIC.2007.4745511","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745511","url":null,"abstract":"In this study pediatric and adult Ventricular Tachycardia (VT) are used to test the efficiency of an AED analysis algorithm. Statistical assessment of the four significant parameters that define the shock-noshock classification algorithm has been performed. The following parameters are considered: Pulse Rate (PR), Waveform Power Ratio (WPR), and two morphological parameters, Baseline Content (BC) and Probability Distribution Width (PDW). A set of 76 adult and 55 pediatric shockable VT episodes is considered to measure the sensitivity of the classification algorithm originally developed for adult patients (100% for rapid adult VT). The sensitivity for the whole pediatric set is 96.36 %, but increases to 100% for the 1-8 years of age subgroup.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"10 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134529281","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745552
J. Rodríguez-Sotelo, D. Cuesta-Frau, G. Castellanos-Domínguez
Clustering is advisable technique for analysis and interpretation of long-term ECG Holter records. As a non-supervised method, several challenges are posed due to factors such as signal length (very long duration), noise presence, dynamic behavior and morphology variability (different patient physiology and/or pathology). This work describes an improved version of the k-means clustering algorithm (J-means) for this task. In order to reduce the number of heartbeats to process, a preclustering stage is also employed. Dissimilarity measure calculation is based on the Dynamic Time Warping approach. To assess the validity of the proposed method, a comparative study is carried out, using k-means, k-medians, hk-means, and J-means. Heartbeat features are extracted by means of WT coefficients and trace segmentation. Best results were achieved by the J-means algorithm, which reduces the clustering error down to 4.5% while the critical error tends to the minimal value.
{"title":"An improved method for unsupervised analysis of ECG beats based on WT features and J-means clustering","authors":"J. Rodríguez-Sotelo, D. Cuesta-Frau, G. Castellanos-Domínguez","doi":"10.1109/CIC.2007.4745552","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745552","url":null,"abstract":"Clustering is advisable technique for analysis and interpretation of long-term ECG Holter records. As a non-supervised method, several challenges are posed due to factors such as signal length (very long duration), noise presence, dynamic behavior and morphology variability (different patient physiology and/or pathology). This work describes an improved version of the k-means clustering algorithm (J-means) for this task. In order to reduce the number of heartbeats to process, a preclustering stage is also employed. Dissimilarity measure calculation is based on the Dynamic Time Warping approach. To assess the validity of the proposed method, a comparative study is carried out, using k-means, k-medians, hk-means, and J-means. Heartbeat features are extracted by means of WT coefficients and trace segmentation. Best results were achieved by the J-means algorithm, which reduces the clustering error down to 4.5% while the critical error tends to the minimal value.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134580140","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745525
S. Babaeizadeh, S.H. Zhou, X. Liu, W.Y. Hu, D. Feild, E. Helfenbein, R. Gregg, J. Lindauer
In this paper, we introduce a new index based on the frequency-domain analysis of heart rate variability, or more precisely, the power spectrum of the instant heart rate signal. This index, called VHFI, is defined as the very high frequency component of the power spectrum normalized to represent its relative value in proportion to the total power minus the very low frequency component. We tested VHFI on patients with known reduced left ventricular function and found that this index has the potential to be a useful tool for quick evaluation of left ventricular function.
{"title":"A novel heart rate variability index for evaluation of left ventricular function using five-minute electrocardiogram","authors":"S. Babaeizadeh, S.H. Zhou, X. Liu, W.Y. Hu, D. Feild, E. Helfenbein, R. Gregg, J. Lindauer","doi":"10.1109/CIC.2007.4745525","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745525","url":null,"abstract":"In this paper, we introduce a new index based on the frequency-domain analysis of heart rate variability, or more precisely, the power spectrum of the instant heart rate signal. This index, called VHFI, is defined as the very high frequency component of the power spectrum normalized to represent its relative value in proportion to the total power minus the very low frequency component. We tested VHFI on patients with known reduced left ventricular function and found that this index has the potential to be a useful tool for quick evaluation of left ventricular function.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124841757","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745531
R. Alcaraz, J. J. Rieta
Recently, it has been suggested that many episodes of atrial fibrillation (AF) may be partially organized at the onset. Moreover, several clinical studies have demonstrated that an AF organization increase occurs prior to its spontaneous termination (paroxysmal AF), which could be used to predict the paroxysmal AF termination. However, although severals AF organization estimators based on invasive and non-invasive analysis have been proposed, the time course of organization in the first and last minutes of AF has not been quantified yet. Thereby, the aim of this work was to study the organization variations within the first and last minutes of paroxysmal AF episodes from surface ECG recordings making use of sample entropy. An organization decrease in the first minutes after AF onset and an increase within the last minute before spontaneous AF termination were obtained, these results were coincident with the conclusions presented in previous clinical works. Thus, it can be concluded that paroxysmal AF organization variations can be assessed from surface recordings without the need of invasive measurements.
{"title":"Organization deterioration assessment from the surface ECG in the onset and termination of paroxysmal atrial fibrillation","authors":"R. Alcaraz, J. J. Rieta","doi":"10.1109/CIC.2007.4745531","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745531","url":null,"abstract":"Recently, it has been suggested that many episodes of atrial fibrillation (AF) may be partially organized at the onset. Moreover, several clinical studies have demonstrated that an AF organization increase occurs prior to its spontaneous termination (paroxysmal AF), which could be used to predict the paroxysmal AF termination. However, although severals AF organization estimators based on invasive and non-invasive analysis have been proposed, the time course of organization in the first and last minutes of AF has not been quantified yet. Thereby, the aim of this work was to study the organization variations within the first and last minutes of paroxysmal AF episodes from surface ECG recordings making use of sample entropy. An organization decrease in the first minutes after AF onset and an increase within the last minute before spontaneous AF termination were obtained, these results were coincident with the conclusions presented in previous clinical works. Thus, it can be concluded that paroxysmal AF organization variations can be assessed from surface recordings without the need of invasive measurements.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131671797","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745499
S. Sayeram, D. Lalush
The purpose of this study is to evaluate 4D reconstruction methods for the processing of gated cardiac single photon emission computed tomography (SPECT) images from obese patients. Clinical gated SPECT projection data were reconstructed using the ordered-sub sets expectation- maximization (OS-EM) and the 4D reseated block- iterative maximum a posteriori (RBI-MAP) reconstruction algorithms. The data were used to derive a relative distribution of quantitative tetrofosmin uptake ratios for the various organs. Using anthropometric data, body sizes were determined for a standard obese male and female NURBS-based cardiac torso (NCAT) phantom. Tetrofosmin uptake ratios were modeled in the obese phantoms and projection data were generated. Poisson noise was simulated, and the noisy data were reconstructed with OS-EM and 4D RBI-MAP. The projected and reconstructed data from the obese phantoms make for a realistic model of tetrofosmin uptake distribution. Qualitatively, 4D processing methods substantially improve visualization of cardiac motion in these very noisy images. We conclude that the tetrofosmin patient models provide a realistic, controllable test vehicle on which to evaluate 4D processing methods for gated cardiac SPECT. 4D processing methods improve the quality of gated SPECT images in obese patients, providing a usable representation of cardiac motion in these difficult-to-image patients.
{"title":"Performance evaluation of 4D reconstruction methods for gated cardiac single photon emission computed tomography in obese patients","authors":"S. Sayeram, D. Lalush","doi":"10.1109/CIC.2007.4745499","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745499","url":null,"abstract":"The purpose of this study is to evaluate 4D reconstruction methods for the processing of gated cardiac single photon emission computed tomography (SPECT) images from obese patients. Clinical gated SPECT projection data were reconstructed using the ordered-sub sets expectation- maximization (OS-EM) and the 4D reseated block- iterative maximum a posteriori (RBI-MAP) reconstruction algorithms. The data were used to derive a relative distribution of quantitative tetrofosmin uptake ratios for the various organs. Using anthropometric data, body sizes were determined for a standard obese male and female NURBS-based cardiac torso (NCAT) phantom. Tetrofosmin uptake ratios were modeled in the obese phantoms and projection data were generated. Poisson noise was simulated, and the noisy data were reconstructed with OS-EM and 4D RBI-MAP. The projected and reconstructed data from the obese phantoms make for a realistic model of tetrofosmin uptake distribution. Qualitatively, 4D processing methods substantially improve visualization of cardiac motion in these very noisy images. We conclude that the tetrofosmin patient models provide a realistic, controllable test vehicle on which to evaluate 4D processing methods for gated cardiac SPECT. 4D processing methods improve the quality of gated SPECT images in obese patients, providing a usable representation of cardiac motion in these difficult-to-image patients.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132490026","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745449
D. Farina, O. Dossel
A model-based approach to noninvasively determine the location and size of the infarction scar is proposed, that in addition helps to estimate the risk of arrhythmias. The approach is based on the optimization of an electrophysiological heart model with an introduced infarction scar to fit the multichannel ECG measured on the surface of the patient's thorax. This model delivers the distributions of transmembrane voltages (TMV) within the ventricles during a single heart cycle. The forward problem of electrocardiography is solved in order to obtain the simulated ECG of the patient. This ECG is compared with the measured one, the difference is used as the criterion for optimization of model parameters, which include the site and size of infarction scar.
{"title":"Model-based approach to the localization of infarction","authors":"D. Farina, O. Dossel","doi":"10.1109/CIC.2007.4745449","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745449","url":null,"abstract":"A model-based approach to noninvasively determine the location and size of the infarction scar is proposed, that in addition helps to estimate the risk of arrhythmias. The approach is based on the optimization of an electrophysiological heart model with an introduced infarction scar to fit the multichannel ECG measured on the surface of the patient's thorax. This model delivers the distributions of transmembrane voltages (TMV) within the ventricles during a single heart cycle. The forward problem of electrocardiography is solved in order to obtain the simulated ECG of the patient. This ECG is compared with the measured one, the difference is used as the criterion for optimization of model parameters, which include the site and size of infarction scar.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131663243","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745588
E. Pueyo, E. Laciar, E. Anzuola, P. Laguna, R. Jané
In this study the slopes of the QRS complex are evaluated for determination of the degree of myocardial damage in chronic chagasic patients. Previous studies have demonstrated the ability of the slope indices to reflect alterations in the conduction velocity of the cardiac impulse. Results obtained in the present study show that chronic chagasic patients have significantly flatter QRS slopes as compared to healthy subjects. Not only that but the extent of slope lessening turns out to be proportional to the degree of myocardial damage caused by the disease. Additionally, when incorporating the slope indices into a classification analysis together with other indices indicative of the presence of ventricular late potentials obtained from high resolution electrocardiography, results show that the percentages of correct classification increase up to 62.5%, which means eight points above the percentages obtained prior to incorporation of the slope indices. It can be concluded that QRS slopes have great potential for assessing the degree of severity associated with Chagaspsila disease.
{"title":"Assessment of myocardial damage in chronic chagasic patients using QRS slopes","authors":"E. Pueyo, E. Laciar, E. Anzuola, P. Laguna, R. Jané","doi":"10.1109/CIC.2007.4745588","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745588","url":null,"abstract":"In this study the slopes of the QRS complex are evaluated for determination of the degree of myocardial damage in chronic chagasic patients. Previous studies have demonstrated the ability of the slope indices to reflect alterations in the conduction velocity of the cardiac impulse. Results obtained in the present study show that chronic chagasic patients have significantly flatter QRS slopes as compared to healthy subjects. Not only that but the extent of slope lessening turns out to be proportional to the degree of myocardial damage caused by the disease. Additionally, when incorporating the slope indices into a classification analysis together with other indices indicative of the presence of ventricular late potentials obtained from high resolution electrocardiography, results show that the percentages of correct classification increase up to 62.5%, which means eight points above the percentages obtained prior to incorporation of the slope indices. It can be concluded that QRS slopes have great potential for assessing the degree of severity associated with Chagaspsila disease.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132910858","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}
Pub Date : 2007-09-01DOI: 10.1109/CIC.2007.4745573
M. Nováková, K. Nogová, J. Bardoňová, I. Provazník
Voltage-sensitive dyes (VSDpsilas) undergo changes in their electronic structure, and consequently their fluorescence spectra, in response to changes in the surrounding electric field and are therefore used for recording of monophasic action potentials (MAPs) by optical method. S.-c. phototoxic effects of VSDs appear under intense illumination and include alterations in heart electrical signals. To examine putative side effects of VSD di-4-ANEPPS in rabbit hearts, we studied electrogram, mean coronary flow and formation of hydroxyl radicals in the control, staining and washout periods and during illumination. Possible ultrastructural changes were examined by electron microscopy. Rabbit myocardium is resistant to di-4-ANEPPS side effects during staining and also resistant to bleaching during intense illumination since only minor changes in ECG and no change in other parameters were observed.
{"title":"Tissue response during staining and illumination of voltage-sensitive dye in rabbit myocardium","authors":"M. Nováková, K. Nogová, J. Bardoňová, I. Provazník","doi":"10.1109/CIC.2007.4745573","DOIUrl":"https://doi.org/10.1109/CIC.2007.4745573","url":null,"abstract":"Voltage-sensitive dyes (VSDpsilas) undergo changes in their electronic structure, and consequently their fluorescence spectra, in response to changes in the surrounding electric field and are therefore used for recording of monophasic action potentials (MAPs) by optical method. S.-c. phototoxic effects of VSDs appear under intense illumination and include alterations in heart electrical signals. To examine putative side effects of VSD di-4-ANEPPS in rabbit hearts, we studied electrogram, mean coronary flow and formation of hydroxyl radicals in the control, staining and washout periods and during illumination. Possible ultrastructural changes were examined by electron microscopy. Rabbit myocardium is resistant to di-4-ANEPPS side effects during staining and also resistant to bleaching during intense illumination since only minor changes in ECG and no change in other parameters were observed.","PeriodicalId":406683,"journal":{"name":"2007 Computers in Cardiology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121806601","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}
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