2)Basic information of ECG machine and ECG paper (From Fig.1-2 to Fig.1-4) 心电图机和心电图纸的基本信息（图1-2～图1-4）

Inventor: Willem Einthoven (1860-1927)

Nationality: Dutch

Fields: Physiology

Institutions: Leiden University

Known for: Electrocardiogram

Notable awards: Nobel Prize in Medicine in 1924

心电图之父：威廉·埃因托芬 (1860—1927)

国籍：荷兰

专业：生理学

机构：莱顿大学

闻名：心电图

获奖：1924年荣获诺贝尔医学奖

ECG paper interpretation (Fig.1-4) 心电图纸解析（图1-4）

ECG drawings printed by Electrocardiographs are consist of 1mm×1mm small squares.Normally, a standard ECG is printed at 25mm per second or 25 small squares per second. So it is used to calculate the duration of individual waves.

We need to master the following key information before learning ECG:

• One small square vertically indicates 0.1 millivolt. One large square (5 small squares)vertically indicates 0.5 millivolt.

• One small square horizontally indicates 0.04 seconds (the speed of ECG paper is 25 millimeters per second). One large square (5 small squares) horizontally indicates 0.2 seconds.

心电图机打印出的心电图纸由1mm×1mm的方格组成。一般来说，心电图纸的走纸速度为25mm/s，即每秒走纸25个小方格。因此，它用于计算每个波形的持续时间。

在学习心电图之前，我们需要掌握如下关键信息：

• 1小纵格代表0.1毫伏的电压，即1大格（5小格）代表0.5毫伏；

• 1小横格代表0.04秒(心电图走纸速度=25mm/s)，即1大格（5小格）代表0.2秒。

Heart rate calculation (Fig.1-5 and Tab.1-1)

a) Measure the P-P or R-R interval as usual.

b) With regular rhythm heart rate: Beat per minute=60/P-P or R-R interval(s). If rhythm is irregular (i.e. atrial fibrillation), 8-10 consecutive R-R intervals should be measured. Ventricle rate=60/the average of R-R intervals.

心率测量（图1-5和表1-1）

a) 测量P-P或者R-R间期。

b) 规整节律下的心率：每分钟心率=60除以P-P或者R-R间期；如节律不规整时（例如心房颤动），应连续测量8～10个R-R间期，心室率即60除以R-R间期的平均值。

Bradycardia: HR<60bpm. Memory tips: R-R interval is more than 5 large squares.

Tachycardia: HR>100bpm. Memory tips: R-R interval is less than 3 large squares.

心动过缓：心率<60次/分；记忆小窍门：R-R间期超过5大格。

心动过速：心率>100次/分；记忆小窍门：R-R间期小于3大格。