The GU-ECG Database: ECG Datasets for Detection and Classification of Acute Myocardial Ischaemia Through Machine Learning

Gazi University ECG (GU-ECG) database is a set of ECG data acquired from 74 coronary artery disease patients with severe stenosis (>70%) in at least one coronary artery who had symptoms of chest pain and were planned to undergo elective percutaneous transluminal coronary angioplasty (PTCA) at Department of Cardiology, Faculty of Medicine, Gazi University. It is constructed as a result of a clinical research study performed to investigate morphological anomalies in ECG signals that occur during complete coronary artery occlusion caused by PTCA, which reduces myocardial blood flow and induces acute myocardial ischaemia (AMI), leading to significant changes in ST segment and T wave of ECG [1,2].

Before PTCA, 12-lead pre-inflation ECG recordings were continuously acquired prior to catheter insertion to coronary artery at cardiac catheterization laboratory. During PTCA, 12-lead inflation ECG recordings that started during balloon dilatation, then continued throughout balloon inflation period in a major coronary artery were continuously acquired from all patients. In order to achieve optimal angiographic and clinical results of PTCA, balloon was inflated for at least 60 sec. in each patient and it was deflated either due to the occurrence of chest pain, cardiac arrhythmia, hypotension or after a maximum inflation time of 300 sec. After PTCA, 12-lead post-inflation ECG recordings were continuously acquired at least 180 sec. after balloon deflation in coronary artery at catheterization laboratory.

A portable continuous 12-lead ECG device (microCOR, Infron Ltd), which amplifies, digitizes, processes and transmits data wirelessly to its software via a USB adapter in digital format, was used for data acquisition [3]. Recordings were digitized at a sampling rate of 8800 Hz with 24-bit sampling resolution and 0.1 µV amplitude resolution to produce high-resolution digital signals.

Time instants related to balloon inflation and deflation during PTCA, occluded coronary artery in which PTCA is performed and patient's history of previous myocardial infarction were annotated by experienced cardiologists to facilitate the development and performance evaluation of various signal processing and artificial intelligence techniques that will utilize the GU-ECG database [4,5,6,7]. Only patients receiving elective PTCA in one of major coronary arteries were included in the database, whereas patients who had atrial fibrillation, ventricular tachycardia, paced rhythm, or myocardial infarction during data acquisition were excluded.

12-lead pre-inflation, inflation, and post-inflation ECG recordings of each patient are included in experiment data files section with file extension *.ekg, which is data format of microCOR ECG device. Computer software which receives data from ECG device, displays, saves, and exports it to different file formats is included in experiment data files section with file extension *.exe, which is executable file format of microCOR PC software.

加济大学心电图（GU-ECG）数据库汇集了74例患有严重冠状动脉狭窄（>70%）且伴有胸痛症状的患者的心电图数据。这些患者计划在加济大学医学院心脏病学系的经皮冠状动脉腔内成形术（PTCA）中心接受选择性PTCA手术。该数据库的构建源于一项旨在研究PTCA引起的完全冠状动脉闭塞所致的心电图信号形态学异常的临床研究。PTCA减少心肌血流量，诱发急性心肌缺血（AMI），从而导致心电图ST段和T波发生显著变化[1,2]。

在PTCA术前，心脏导管室在导管插入冠状动脉之前，对12导联预充盈心电图进行了连续记录。在PTCA过程中，从所有患者中连续采集了在球囊扩张开始时启动的12导联充盈心电图记录，并在主要冠状动脉球囊充盈期间持续进行。为了实现PTCA的最佳血管造影和临床结果，球囊在每位患者体内至少充盈60秒，并在出现胸痛、心律失常、低血压或最大充盈时间达到300秒后放气。PTCA后，在导管室冠状动脉球囊放气至少180秒后，进行了连续的12导联放气后心电图记录。

数据采集使用了一种便携式连续12导联心电图设备（microCOR，Infron Ltd），该设备通过USB适配器将数据无线传输至其软件，以数字格式进行放大、数字化、处理和传输。记录以8800 Hz的采样率、24位采样分辨率和0.1 µV的幅度分辨率进行数字化，以产生高分辨率数字信号。

与PTCA过程中球囊充盈和放气相关的时间点、PTCA实施的闭塞冠状动脉以及患者既往心肌梗死病史由经验丰富的心脏病学家标注，以促进利用GU-ECG数据库开发各种信号处理和人工智能技术的性能评估[4,5,6,7]。数据库中仅包括在一主要冠状动脉中接受选择性PTCA的患者，而那些在数据采集过程中出现心房颤动、室性心动过速、起搏心律或心肌梗死的患者被排除在外。

每个患者的12导联预充盈、充盈和放气后心电图记录包含在实验数据文件部分，文件扩展名为*.ekg，这是microCOR心电图设备的数据格式。此外，还包括接收来自心电图设备的数据、显示、保存并将数据导出为不同文件格式的计算机软件，文件扩展名为*.exe，这是microCOR PC软件的可执行文件格式。