針對三導極無線心電圖系統之強韌性心電訊號合成方式

Abstract

根據世界衛生組織於 2011 更新全球前十大死因數據顯示缺血性心 臟病名列第一，為了降低因缺血性心臟病以致於心肌梗塞死亡之人數，然而心臟病發作之徵兆檢測與預警有賴於可隨身攜帶之心電訊號監控系統，此類之系統一般泛稱為 Ambulatory ECG (AECG)稱為可移動心電圖,若是病人可以長時間配戴無線多導極 ECG 系統，必定可以幫助心肌梗塞之高危險群患者能於發病時及時就醫。但在醫院的心臟科醫生，都是受標準12導極的心電圖訓練，因此本篇論文提出一種新式的12 導極訊號還原方法(12-lead ECG synthesis method)，論文中包含了如何找尋3導極無線心電圖最好的量測位置、12 導極的訊號重建之演算法以及提出一個適合受專業訓練的醫護人所使用的量測位置。12導極重建演算法包含了考量不同時間點的12導極心電圖訊號以及導極與導極之間的關係性，在實驗結果中，重建訊號與真實訊號比對之後，它們之間的相關係數可以高達0.98。此外電極與電極之間的距離可以縮短成10cm，這個大小跟OK 繃大小差不多，這個大大提升長時間配戴無線心電圖的可行性。

A body area network is developed for a 3-Lead wireless electrocardiography (ECG) monitoring system. To measure the 3-Lead ECG signals without using wires for electrodes to connect to a common ground, we study a new ECG sensing method that directly and synchronously measures the voltage differences across the nearby electrodes of distributed ECG leads. Due to all cardiologists are well-trained and used to diagnose the symptoms of heart diseases with the standard 12-lead ECG,then a new signal synthesis and tracking method is developed for a 3-Lead wireless electrocardiography (ECG) system. Exploiting the temporal correlations in ECG signals, the standard 12-lead ECG signals can be synthesized with high precision by using only three differential pairs of electrodes. The correlations between the original and synthesized ECG leads can be as high as 0.98. And the separation between the two electrodes of a pair can be drastically reduced to around 10 cm, which is about the size of a medium adhesive tape. Experiment results also show that the proposed ECG synthesis method is much more robust to variations in acquisition positions when taking into account the spatial correlations among the ECG leads in syntheses. This greatly improves the feasibility of using fully wireless ECG systems on the long-term monitoring and diagnosis of heart diseases. We propose a candidate electrode positions , ($V1-V2$), ($V3-V4$), and ($V5-V6$), from the typical acquisition positions of the standard 12-lead ECG system. Besides, we also propose the other electrode positions by analyzing the measurement data form ten subjects of NCTU as well as the four data sets in MIT-BIH database.