Electrocardiogram

—The ECG machine is designed to recognise and record any electrical activity within the heart.

—provide information about the function of the intracardiac conducting tissue and reflects the presence of cardiac disease through its electrical properties.

—Some conditions produce characteristic patterns of ECG abnormality.

—The indications for exercise electrocardiography include the investigation of angina and post-myocardial infarction assessment as well as the postoperative examination of bypass surgery.

•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)