U. Illindala, R. Grimm, A. Morehead, S. Chandra, N. Greenberg, J.D. Thomas
Spectral Doppler echocardiography has been accepted as the standard non-invasive diagnostic procedure for evaluating cardiac hemodynamics. However, clinical ability to draw conclusions from derived parameters is dependent on manual tracings of the Doppler flow patterns. These manual tracings are cumbersome and subjective, with very poor reproducibility. A new automated signal analysis and envelope detection method has been developed which can trace continuous as well as pulsed Doppler flows and offers reliable results while eliminating inter-observer variability. Audio Doppler signals are acquired from normal subjects simultaneous with routine video storage of the spectral velocity data. A signal processing technique highlighted by a method of flow generation using short time Fourier transforms provides a digital Doppler flow pattern. Customized software, using the modal velocity as a guide, has been developed for envelope detection and parameter estimation of such digital signals. These results have been compared with the observer traced and estimated parameters.
{"title":"Automated analysis of transmitral and aortic Doppler velocity profiles using audio signal processing","authors":"U. Illindala, R. Grimm, A. Morehead, S. Chandra, N. Greenberg, J.D. Thomas","doi":"10.1109/CIC.1996.542505","DOIUrl":"https://doi.org/10.1109/CIC.1996.542505","url":null,"abstract":"Spectral Doppler echocardiography has been accepted as the standard non-invasive diagnostic procedure for evaluating cardiac hemodynamics. However, clinical ability to draw conclusions from derived parameters is dependent on manual tracings of the Doppler flow patterns. These manual tracings are cumbersome and subjective, with very poor reproducibility. A new automated signal analysis and envelope detection method has been developed which can trace continuous as well as pulsed Doppler flows and offers reliable results while eliminating inter-observer variability. Audio Doppler signals are acquired from normal subjects simultaneous with routine video storage of the spectral velocity data. A signal processing technique highlighted by a method of flow generation using short time Fourier transforms provides a digital Doppler flow pattern. Customized software, using the modal velocity as a guide, has been developed for envelope detection and parameter estimation of such digital signals. These results have been compared with the observer traced and estimated parameters.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130071368","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}
In previous studies on the inverse problem of electrocardiography, Generalized Eigensystem (GES) methods performed better than more conventional techniques such as singular valve decomposition or Tikhonov regularization. Here, the authors introduce Geometric Eigenvector Mapping (GEM) as a technique for accelerating the eigenvector computations which are the basis for the GES methods. The GEM method provided substantial reductions in eigenvector computation time with improvements ranging from 22% to 74%.
{"title":"Accelerating eigenvector computations for inverse electrocardiography applications","authors":"J. Schelert, L. Olson, M. Muff, R. Throne","doi":"10.1109/CIC.1996.542554","DOIUrl":"https://doi.org/10.1109/CIC.1996.542554","url":null,"abstract":"In previous studies on the inverse problem of electrocardiography, Generalized Eigensystem (GES) methods performed better than more conventional techniques such as singular valve decomposition or Tikhonov regularization. Here, the authors introduce Geometric Eigenvector Mapping (GEM) as a technique for accelerating the eigenvector computations which are the basis for the GES methods. The GEM method provided substantial reductions in eigenvector computation time with improvements ranging from 22% to 74%.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"254 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116391631","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}
G. Porenta, D. Moertl, M. Haddad, T. Binder, H. Baumgartner, G. Maurer, P. Probst
State-of-the-art sensor technology permits development of miniaturized probes to perform intracoronary measurements. To facilitate signal analysis and diagnostic interpretation, we developed a computer based signal processing system for on-line use to acquire, store, display and process intracoronary signals of peak Doppler flow velocity and coronary pressures. The system consists of a desktop workstation (Apple Macintosh 840 av) that is equipped with an A/D processing board (NB-MIO 16X, National Instruments). Acquisition is controlled by a graphical user interface simulating a virtual instrument (LabView 3.0). ECG, Doppler velocity and pressure are continuously displayed and can be stored in 40s time blocks to document hemodynamics at baseline conditions and after pharmacologic interventions such as adenosine or dipyridamole to delineate coronary reserve. Signal analysis is performed using commercially available software (Mathlab 4.0). With this system, graphical displays of coronary hemodynamics such as pressure velocity curves under different conditions can be quickly generated and presented to the physician during the catheterization procedure.
最先进的传感器技术允许开发小型化探针来进行冠状动脉内测量。为了便于信号分析和诊断解释，我们开发了一个基于计算机的信号处理系统，用于在线获取、存储、显示和处理冠状动脉内峰值多普勒血流速度和冠状动脉压力的信号。该系统由一个桌面工作站(Apple Macintosh 840 av)和一个a /D处理板(NB-MIO 16X, National Instruments)组成。采集由模拟虚拟仪器的图形用户界面(LabView 3.0)控制。心电图、多普勒速度和压力可连续显示，并可每隔40个时间块存储，以记录基线条件下和经腺苷或双嘧达莫等药物干预后的血流动力学，以描绘冠状动脉储备。信号分析使用市售软件(Mathlab 4.0)进行。使用该系统，可以快速生成冠状动脉血流动力学的图形显示，如不同条件下的压力速度曲线，并在导管插入过程中呈现给医生。
{"title":"A signal processing system for the analysis of coronary hemodynamics based on guidewire measurements","authors":"G. Porenta, D. Moertl, M. Haddad, T. Binder, H. Baumgartner, G. Maurer, P. Probst","doi":"10.1109/CIC.1996.542510","DOIUrl":"https://doi.org/10.1109/CIC.1996.542510","url":null,"abstract":"State-of-the-art sensor technology permits development of miniaturized probes to perform intracoronary measurements. To facilitate signal analysis and diagnostic interpretation, we developed a computer based signal processing system for on-line use to acquire, store, display and process intracoronary signals of peak Doppler flow velocity and coronary pressures. The system consists of a desktop workstation (Apple Macintosh 840 av) that is equipped with an A/D processing board (NB-MIO 16X, National Instruments). Acquisition is controlled by a graphical user interface simulating a virtual instrument (LabView 3.0). ECG, Doppler velocity and pressure are continuously displayed and can be stored in 40s time blocks to document hemodynamics at baseline conditions and after pharmacologic interventions such as adenosine or dipyridamole to delineate coronary reserve. Signal analysis is performed using commercially available software (Mathlab 4.0). With this system, graphical displays of coronary hemodynamics such as pressure velocity curves under different conditions can be quickly generated and presented to the physician during the catheterization procedure.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114695073","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}
Development and evaluation of automated decision support systems requires large amounts of well-characterized, reproducible test data. The MIMIC (Multi-parameter Intelligent Monitoring for Intensive Care) Database is intended to meet these needs. The database, currently nearing completion, will include 100 patient records, each typically containing between 24 and 48 hours of continuous data recorded from patient monitors in the medical, surgical, and cardiac intensive care units of Boston's Beth Israel Hospital. Each record will be accompanied by detailed clinical data derived from the patient's medical record and from the hospital's on-line medical information systems. We select patients to record from those likely to be hemodynamically unstable during the planned recording period. We expect to complete the selection of the recordings to be included in the database by the end of 1996, and to make the database available to other researchers shortly thereafter.
{"title":"A database to support development and evaluation of intelligent intensive care monitoring","authors":"George Moody, R. G. Mark","doi":"10.1109/CIC.1996.542622","DOIUrl":"https://doi.org/10.1109/CIC.1996.542622","url":null,"abstract":"Development and evaluation of automated decision support systems requires large amounts of well-characterized, reproducible test data. The MIMIC (Multi-parameter Intelligent Monitoring for Intensive Care) Database is intended to meet these needs. The database, currently nearing completion, will include 100 patient records, each typically containing between 24 and 48 hours of continuous data recorded from patient monitors in the medical, surgical, and cardiac intensive care units of Boston's Beth Israel Hospital. Each record will be accompanied by detailed clinical data derived from the patient's medical record and from the hospital's on-line medical information systems. We select patients to record from those likely to be hemodynamically unstable during the planned recording period. We expect to complete the selection of the recordings to be included in the database by the end of 1996, and to make the database available to other researchers shortly thereafter.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114786080","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}
P. Lu, D. Wencker, M. Szulc, P. Supino, R. Mueller, B. Zola, G. Casadei, P. Zanzonico, E. Herrold, J. Borer
To determine whether administration of nitroglycerin (NTG) and computer-aided image analysis applied 3 hr after exercise (ex) can provide data equivalent to those available from redistribution (R) imaging 24 hr post-ex, 3 hr and 24 hr post-ex imaging with and without NTG were employed to study 15 pts with 37 coronary artery territories which were abnormal post-ex. In the 3 hr R images after NTG, 19/37 territories showed R, while only 12 were identified in the absence of NTG (p=.07); at 24 hr post-ex, 24/37 territories had R with NTG vs 13 without (p<.01). At 3 hr, defect size decrease was significantly greater after NTG than without NTG (NTG:12% reduction vs control:6%, p<.03). At 24 hr, defect size decrease was similar with each strategy. NTG administration after ex improves viable myocardium detection compared to standard R imaging without NTG.
{"title":"Computer-aided quantitation of the effect of nitroglycerin and isosorbide dinitrate on thallium-201 redistribution in patients with myocardial infarction","authors":"P. Lu, D. Wencker, M. Szulc, P. Supino, R. Mueller, B. Zola, G. Casadei, P. Zanzonico, E. Herrold, J. Borer","doi":"10.1109/CIC.1996.542542","DOIUrl":"https://doi.org/10.1109/CIC.1996.542542","url":null,"abstract":"To determine whether administration of nitroglycerin (NTG) and computer-aided image analysis applied 3 hr after exercise (ex) can provide data equivalent to those available from redistribution (R) imaging 24 hr post-ex, 3 hr and 24 hr post-ex imaging with and without NTG were employed to study 15 pts with 37 coronary artery territories which were abnormal post-ex. In the 3 hr R images after NTG, 19/37 territories showed R, while only 12 were identified in the absence of NTG (p=.07); at 24 hr post-ex, 24/37 territories had R with NTG vs 13 without (p<.01). At 3 hr, defect size decrease was significantly greater after NTG than without NTG (NTG:12% reduction vs control:6%, p<.03). At 24 hr, defect size decrease was similar with each strategy. NTG administration after ex improves viable myocardium detection compared to standard R imaging without NTG.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134405433","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. R. Román, D. W. Davis, J. Michels, V. Dávila-Román
A model-based method for real-time ECG diagnosis has been formulated in which information from multiple leads is processed simultaneously with a set of multivariable, linear, time-invariant filters in parallel. A diagnosis is reached by examining the filter outputs (residuals) using statistical criteria. Individual criteria diagnostics are fused into a single, final diagnostic. The methodology is applied to the discrimination of complete RBBB and LBBB from normals, using the QRS complex from 30 independent cases of a standard database. The cases are assigned randomly into a design set and a testing set of 15 cases each. Correct diagnosis assessment is 100% for the design set, and 93% for the testing set. The method is extendible to other types of cardiac abnormalities and to multiple, distinct physiologic sensing devices.
{"title":"Model-based multichannel diagnosis of cardiac conduction abnormalities","authors":"J. R. Román, D. W. Davis, J. Michels, V. Dávila-Román","doi":"10.1109/CIC.1996.542572","DOIUrl":"https://doi.org/10.1109/CIC.1996.542572","url":null,"abstract":"A model-based method for real-time ECG diagnosis has been formulated in which information from multiple leads is processed simultaneously with a set of multivariable, linear, time-invariant filters in parallel. A diagnosis is reached by examining the filter outputs (residuals) using statistical criteria. Individual criteria diagnostics are fused into a single, final diagnostic. The methodology is applied to the discrimination of complete RBBB and LBBB from normals, using the QRS complex from 30 independent cases of a standard database. The cases are assigned randomly into a design set and a testing set of 15 cases each. Correct diagnosis assessment is 100% for the design set, and 93% for the testing set. The method is extendible to other types of cardiac abnormalities and to multiple, distinct physiologic sensing devices.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132724884","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}
Recent studies suggest that defibrillation success is influenced by the production of new activations at (or after) the end of a post-shock refractory period. The authors examined if post-shock spatial gradients of transmembrane potential (GTMP) could serve as a possible source for electrotonically evoking post-shock activations. Previously measured action potential prolongations were used to mathematically model the post-shock recovery of tissue along a simple one-dimensional strip and to find GTMP. Following both monophasic and biphasic shocks, GTMP first increased and then decreased with time (peak at 65 to 90 ms). Peak GTMP decreased for stronger shocks and occurred earlier (/spl ap/15 ms) after biphasic shocks. These results are consistent with the effect of shock intensity and waveform on defibrillation and with the hypothesis that GTMP can cause defibrillation failure by evoking post-shock activations.
{"title":"Post-shock spatial gradients of transmembrane potential as a source for post-shock activations during failed defibrillation","authors":"R. Sweeney, R. Gill, P. R. Reid","doi":"10.1109/CIC.1996.542546","DOIUrl":"https://doi.org/10.1109/CIC.1996.542546","url":null,"abstract":"Recent studies suggest that defibrillation success is influenced by the production of new activations at (or after) the end of a post-shock refractory period. The authors examined if post-shock spatial gradients of transmembrane potential (GTMP) could serve as a possible source for electrotonically evoking post-shock activations. Previously measured action potential prolongations were used to mathematically model the post-shock recovery of tissue along a simple one-dimensional strip and to find GTMP. Following both monophasic and biphasic shocks, GTMP first increased and then decreased with time (peak at 65 to 90 ms). Peak GTMP decreased for stronger shocks and occurred earlier (/spl ap/15 ms) after biphasic shocks. These results are consistent with the effect of shock intensity and waveform on defibrillation and with the hypothesis that GTMP can cause defibrillation failure by evoking post-shock activations.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133482085","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}
G. Stalidis, N. Maglaveras, A. Dimitriadis, C. Pappas, M. Strintzis, S. N. Efstratiadis
The propagation of the electrical activity of the heart is simulated over regions containing infarcted tissue. The method is applied to patients suffering from ischemia, in order to study the impact of the injury on the electrical function of the heart. The spatial distribution of the infarcted tissue and the shape of the endocardial and the epicardial surfaces are derived from MRI data using a semiautomatic method based on 3D Fourier parametric modeling. A 2D grid is then constructed which represents a selected part of the epicardial surface and contains information about the condition of the tissue. This grid is used as input to the simulation algorithm which estimates the ionic currents over time and the propagation of the electric impulse.
{"title":"Application of a 3-D ischemic heart model derived from MRI data to the simulation of the electrical activity of the heart","authors":"G. Stalidis, N. Maglaveras, A. Dimitriadis, C. Pappas, M. Strintzis, S. N. Efstratiadis","doi":"10.1109/CIC.1996.542540","DOIUrl":"https://doi.org/10.1109/CIC.1996.542540","url":null,"abstract":"The propagation of the electrical activity of the heart is simulated over regions containing infarcted tissue. The method is applied to patients suffering from ischemia, in order to study the impact of the injury on the electrical function of the heart. The spatial distribution of the infarcted tissue and the shape of the endocardial and the epicardial surfaces are derived from MRI data using a semiautomatic method based on 3D Fourier parametric modeling. A 2D grid is then constructed which represents a selected part of the epicardial surface and contains information about the condition of the tissue. This grid is used as input to the simulation algorithm which estimates the ionic currents over time and the propagation of the electric impulse.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"8 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125000828","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}
Describes a technique for studying global and regional motion patterns of the right ventricle (RV) using contrast echocardiography in conjunction with videodensitometric measurements. Two ml of echo-contrast (Haemaccel, Behring/Hoechst) was injected as a bolus into a brachial vein. An image sequence visualizing the RV echocontrast filling and elimination was analysed in real-time. The mean image intensity of predefined regions of interest (ROI) at the inflow tract and apex was computed over time. This signal was modelled by two exponentials which time constants were used for discriminating between a group of healthy subjects and patients with arrythmogenic right ventricular dysplasia (ARVD). The ARVD patients had delayed filling and elimination rates in the RV apex region as compared to the controls (p<0.05). Also, for the ARVD patients, the filling rate was lower in the apex region as compared to the inflow tract (p<0.001). In addition to ROI echo-contrast analysis, time-of-arrival and time-of-departure maps were developed. These maps show the overall ventricular-filling and elimination patterns as well as their timings. It was concluded that contrast-echocardiography with real-time video densiometry can be an effective means for studying right ventricular function.
{"title":"Videodensitometric measurements in contrast-echocardiology","authors":"T. Gustavsson, M. Beckman-Suurkula","doi":"10.1109/CIC.1996.542635","DOIUrl":"https://doi.org/10.1109/CIC.1996.542635","url":null,"abstract":"Describes a technique for studying global and regional motion patterns of the right ventricle (RV) using contrast echocardiography in conjunction with videodensitometric measurements. Two ml of echo-contrast (Haemaccel, Behring/Hoechst) was injected as a bolus into a brachial vein. An image sequence visualizing the RV echocontrast filling and elimination was analysed in real-time. The mean image intensity of predefined regions of interest (ROI) at the inflow tract and apex was computed over time. This signal was modelled by two exponentials which time constants were used for discriminating between a group of healthy subjects and patients with arrythmogenic right ventricular dysplasia (ARVD). The ARVD patients had delayed filling and elimination rates in the RV apex region as compared to the controls (p<0.05). Also, for the ARVD patients, the filling rate was lower in the apex region as compared to the inflow tract (p<0.001). In addition to ROI echo-contrast analysis, time-of-arrival and time-of-departure maps were developed. These maps show the overall ventricular-filling and elimination patterns as well as their timings. It was concluded that contrast-echocardiography with real-time video densiometry can be an effective means for studying right ventricular function.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125068501","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}
P. Clavario, A. Pini, M. Pedevilla, F. Copello, M. De Martini, G. Airoldi, D. Massari, A. Biagini, U. Trucco
Twenty-nine hypertensive patients scheduled for minor abdominal surgical procedures and chronically treated with any antihypertensive oral therapy (AOT), underwent a 24-hour noninvasive blood pressure monitoring (ABPM). Fifteen days before the operation, the AOT was substituted with transdermal clonidine (TSC) 0.1 mg./day or 0.2 mg./day. Two days before and two days after the surgical procedure, the ABPM was repeated. The Fourier transform was used for the smoothing of the blood pressure curves. The authors found no statistically significant difference between the AOT profiles and the TSC profiles. As expected, they observed a significant increase in the heart rate in the post surgery ABPM in comparison with the ABPM before the operation. The use of transdermal clonidine is particularly useful in the surgical settings, because it maintains stable blood pressure profiles throughout the perisurgical period and it reduces the need for nursing time.
{"title":"Fourier transform analysis of the blood pressure profiles in transdermal clonidine treated hypertensive patients undergoing abdominal surgery","authors":"P. Clavario, A. Pini, M. Pedevilla, F. Copello, M. De Martini, G. Airoldi, D. Massari, A. Biagini, U. Trucco","doi":"10.1109/CIC.1996.542589","DOIUrl":"https://doi.org/10.1109/CIC.1996.542589","url":null,"abstract":"Twenty-nine hypertensive patients scheduled for minor abdominal surgical procedures and chronically treated with any antihypertensive oral therapy (AOT), underwent a 24-hour noninvasive blood pressure monitoring (ABPM). Fifteen days before the operation, the AOT was substituted with transdermal clonidine (TSC) 0.1 mg./day or 0.2 mg./day. Two days before and two days after the surgical procedure, the ABPM was repeated. The Fourier transform was used for the smoothing of the blood pressure curves. The authors found no statistically significant difference between the AOT profiles and the TSC profiles. As expected, they observed a significant increase in the heart rate in the post surgery ABPM in comparison with the ABPM before the operation. The use of transdermal clonidine is particularly useful in the surgical settings, because it maintains stable blood pressure profiles throughout the perisurgical period and it reduces the need for nursing time.","PeriodicalId":433138,"journal":{"name":"Computers in Cardiology 1996","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129850557","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：