1、多部位心電標(biāo)測（Electrocardial potential mapping）南開大學(xué)物理學(xué)院生物物理系 李川勇Nankai University, CY Li 9/14/20229/17/20221Electrocardial potential mapping主要內(nèi)容心電信息學(xué)What is ECG（心電圖）?Multi-channel ECG recording system，ECG potential mapping，ECG simulation (forward & inverse ECG)Its applicationsFuture developmentNankai Univ

2、ersity, CY Li 9/14/20222Electrocardial potential mapping心電信息學(xué)In a general term, it refers to the informatics of electrical activity of heart.心電信息學(xué)是把通過各種手段所獲得的有關(guān)心臟電活動的信息，加以處理和分析，總結(jié)出能表示心臟電生理狀態(tài)的特征量或參數(shù)；從而達(dá)到對心臟的認(rèn)識。原始信號的獲得，對原始信號的處理，Nankai University, CY Li 9/14/20223Electrocardial potential mapping一、What

3、is ECG (electrocardiograph)?在整個心臟電激動的綜合過程, 心肌細(xì)胞興奮的產(chǎn)生、傳導(dǎo)和恢復(fù)過程中產(chǎn)生生物電變化，用儀器在人體表面記錄的這種電位變化波形叫心電圖, 1905年Einthoven發(fā)明了心電圖機(jī)記錄心電圖，臨床上有單道心電圖機(jī)、三道心電圖機(jī)、同步12導(dǎo)心電圖機(jī)等；心電圖學(xué)主要研究心電圖的產(chǎn)生原理；分析心電圖的圖形以了解心臟活動的情況，協(xié)助診斷心臟疾病（如心律失常等）并研究其發(fā)生機(jī)理。近年來心電圖學(xué)在理論和實踐方面都有很大進(jìn)展，心電圖診斷已成為臨床醫(yī)學(xué)特別是心臟內(nèi)外學(xué)科的一個重要課題。 Nankai University, CY Li 9/14/20224El

4、ectrocardial potential mapping心室肌細(xì)胞動作電位mV-90-600+200心室肌細(xì)胞動作電位示意圖1234300msNankai University, CY Li 9/14/20225Electrocardial potential mappingMeasurement of ECGNankai University, CY Li 9/14/20227Electrocardial potential mapping標(biāo)準(zhǔn)肢體導(dǎo)聯(lián)Nankai University, CY Li 9/14/20228Electrocardial potential mappingBa

5、sic features of ECGNankai University, CY Li 9/14/202210Electrocardial potential mapping二、Why mapping?傳統(tǒng)12導(dǎo)聯(lián)的電極位置的局限性；80年代提出，指采用多個電極（24-250）均勻排列覆蓋整個軀干，記錄多部位的體表心電信息，以獲得心電信號更多的空間信息。記錄系統(tǒng)：由計算機(jī)控制的多通道數(shù)據(jù)采集系統(tǒng)，完成心電信號的采集、顯示、處理。Nankai University, CY Li 9/14/202211Electrocardial potential mappingmapping system無創(chuàng)

6、檢測,體表心電圖: 標(biāo)準(zhǔn)12導(dǎo)聯(lián)，動態(tài)心電圖，體表多部位檢測(body surface potential mapping， BSPM)，體表心磁圖（Magnetocardiography，MCG），有創(chuàng)檢測,動作電位、單向動作電位的測量，心內(nèi)膜、心外膜心電圖（Endocardial and epicardial electrogram），希氏束電圖（His-Bundle electrogram）Nankai University, CY Li 9/14/202212Electrocardial potential mappingIts features256 channelsBattery

7、poweredThree functions: ECG, EGG, late potentialProgrammable microcontroller12-bit, 800ns ADCProgrammable channel amplification50,100,200,500,1k,2k,5k,10kProgrammable sampling rate2, 10,20,100,200,500,1k,2k (Hz)Nankai University, CY Li 9/14/202214Electrocardial potential mapping2-2、192-channel syste

8、mNankai University, CY Li 9/14/202215Electrocardial potential mapping三、Electrocardial potential mappingBody surface potential mapping (BSPM)體表電位標(biāo)測Epicardial potential mapping心外膜電位標(biāo)測Endocardial potential mapping心內(nèi)膜電位標(biāo)測Three-dimensional potential mapping三維電位標(biāo)測Nankai University, CY Li 9/14/202217Electr

9、ocardial potential mapping3-1. Body surface mappingNankai University, CY Li 9/14/202218Electrocardial potential mappingElectrodesPanel 4x12 : Total of 48 electrodes on 1 connectorNankai University, CY Li 9/14/202219Electrocardial potential mappingMapping in colorNankai University, CY Li 9/14/202220E

10、lectrocardial potential mappingMapping in different timesNankai University, CY Li 9/14/202221Electrocardial potential mapping3-2. Epicardial potential mappingElectrodes: electrode sockNankai University, CY Li 9/14/202222Electrocardial potential mapping3-3. Endocardial potential mappingCardiac cathet

11、er (心導(dǎo)管) for patient,Umbrella electrode for animal experiment; Nankai University, CY Li 9/14/202224Electrocardial potential mapping3-4 Three dimensional mappingEndocardial, epicardial and body surface recording at the same time.With needle electrodes, transmural information can be obtained.Nankai Un

12、iversity, CY Li 9/14/202225Electrocardial potential mappingECG problemssource of electrical current at the surface of the heart : Epropagation through the chest, bioelectric volume conductor : measure of potential at the surface of the torso : T is the electrostatic potential, is the electrical cond

13、uctivity tensor,Nankai University, CY Li 9/14/202227Electrocardial potential mappingTwo modelsForward modelWell-posed problemInverse modelIll-posed problem （病態(tài)問題）Nankai University, CY Li 9/14/202228Electrocardial potential mappingECG inverse problemTo obtain quantitative information about cardiac ac

14、tivity， the inverse problem of electrocardiography must be solved. The ECG inverse approaches are used to non-invasively reconstruct the electrical state of the heart from remote recordings of the electrical activity at the body surface. There are many algorithms available to solve the inverse probl

15、ems.These algorithms must be experimentally validated.Nankai University, CY Li 9/14/202229Electrocardial potential mapping五、The applicationsMethodology of modern BSPM includes:computerised signal collection (計算機(jī)化的信號采集)(simultaneous multichannel recording from several decades of leadpoints on the che

16、st surface, digitalisation of ECG signal, multiplexing and storage), computerised data presentation (計算機(jī)化的數(shù)據(jù)表示)(ECG curves, different templates of maps as a result of application of mathematical interpolations techniques like linear or polynomic, data compression e.g. time integration of the voltage

17、, rapid calculation of quantities not directly measured like different durations, angles etc.) computerised data evaluation (計算機(jī)化的數(shù)據(jù)分析)(signal processing based on medical knowledge). Nankai University, CY Li 9/14/202230Electrocardial potential mappingECG Data evaluationTime series analysis（時間序列分析）,

18、HRV (heart rate variability)Spatial analysis （空間分析）QT dispersion, Inverse ECG, source predictionSpatial pattern of ECG parametersSpatial-temporal analysis （時空分析）Cardiac activation time Nankai University, CY Li 9/14/202231Electrocardial potential mapping心率變異（HRV）HRV是指心率的波動，或者心動周期之間的差異性。正常人的心率有相當(dāng)于平均值1

19、0%的波動，這種波動程度的降低是心臟異常的表現(xiàn)。HRV的分析方法：時域分析，RR間期的標(biāo)準(zhǔn)差，50ms異常頻域分析，LF(0.04-0.15Hz)和HF(0.15-0.4Hz)的功率譜的比較，非線性分析：散點圖，相關(guān)維數(shù)，復(fù)雜度等。Nankai University, CY Li 9/14/202232Electrocardial potential mappingDispersion in ventricular repolarisation (心室復(fù)極不一致)研究表明：室性心律失常是由心室復(fù)極不一致導(dǎo)致的，進(jìn)而研究QT離散度等，通過分析ST段位移的空間分布確定心肌缺血部位等；分析體表、心臟

20、表面的興奮時間圖，判斷異常心肌的部位等；Nankai University, CY Li 9/14/202233Electrocardial potential mapping國內(nèi)的研究狀況浙江大學(xué)生命科學(xué)與醫(yī)學(xué)工程學(xué)系；天津大學(xué)精儀學(xué)院生物醫(yī)學(xué)工程與科學(xué)儀器系；重慶大學(xué)電氣工程學(xué)院； 第四軍醫(yī)大學(xué)生理教研室；首都醫(yī)科大學(xué)Nankai University, CY Li 9/14/202234Electrocardial potential mapping國外研究狀況北美一些大學(xué)，Duke University, University of Utah，Case Western Reserve University，Dalhousie University (Canada)歐洲，University