Electrocardiogram

Original Editor Uchechukwu Chukwuemeka

Top Contributors - Uchechukwu Chukwuemeka, Kim Jackson, Lucinda hampton, Ayelawa Samuel, Karen Wilson and Rishika Babburu

Introduction

An electrocardiogram is also termed an ECG or EKG (K means kardia for heart in Greek), is a simple test that records the heart's electrical activity. The ECG machine is designed to recognise and record any electrical activity within the heart. It provides information about the function of the intracardiac conducting tissue of the heart and reflects the presence of cardiac disease through its electrical properties. Understanding ECG helps to understand how the heart works. With each heartbeat, an electrical impulse starts from the superior part of the heart to the bottom. The impulse prompts the heart to contract and pump blood.

What ECG Test is used

ECG is used to

detect bradycardia and tachycardia

know steady or irregular heart rhythm

The strength and timing of electrical signals as they pass through each part of your heart

The test's results also can suggest other disorders that affect heart function.

Study and detect many heart problems, such as heart attacks, arrhythmia, heart failure.

ECG monitoring for all deeply-sedated patients and for consciously-sedated patients with compromised cardiovascular function

The indications for exercise electrocardiography include the investigation of angina and post-myocardial infarction assessment as well as the postoperative examination of bypass surgery.Some heart problems are easier to diagnose when your heart is working hard and beating fast. During stress

testing, you exercise to make your heart work hard and beat fast while an EKG is done. If you can't exercise,

you'll be given medicine to make your heart work hard and beat fast.

Procedures

Electrode placement

Limb Sensor Application

Place the sensors on a smooth fleshy area of the upper inner arms and lower inner legs. Attach the limb leads.

Chest Sensor Application

Place the 6 Chest sensors on the patient’s chest as follows:

V1 Fourth intercostal space at right border of the sternum

V2 Fourth intercostal space at left border of the sternum

V3 Midway between position V2 and position V4

V4 At the mid-clavicular line in the fifth intercostal space

V5 At the anterior axillary line on the same horizontal level as V4

V6 At the mid-axillary line on the same horizontal level as V4 and V5

Attach the chest leads.

•The first wave (p wave) represents atrial depolarisation (ventricular filling)

•Q wave representing septal depolarisation

•R wave representing ventricular depolarisation

•S wave representing depolarisation of the Purkinje fibres

•QRS is ventricular depolarisation

•T wave is  ventricular repolarisation

•ST segment is a flat line any change shows myocardial infarction

• P wave; QRS complex, and T wave show the 3phase of cardiac cycle in one heart beat

•Sinus arrhythmia, bradycardia, tachycardia,  and asystole

•after the PQRST complex a U wave, seen electrolyte imbalance(potassium)