Echocardiography (ECG)

ECG: a non invasive diagnostic technique that is used in clinical cardiology. It involves the use of ultrasound( either alone or with contrast agent) to asses cardiac structure and function based on the differing ability of various structures within the heart to reflect ultrasound waves. Thus the ECG is able to show the structure of the heart as well as provide a continuous display of the functioning heart throughout its cycle.

There are various types of ECG
1) M-mode
2) 2 dimensional
3) Doppler and colour flow
4) Trans- Oesophageal
5) Stress

Clinical Use of ECG


Valve stenosis
Mitral stenosis
Valve regurgitation
Aortic aneurysms and dissections
Prosthetic heart valves
Cardiac failure: left ventricular function and response to treatment can be assessed. Left and right side cardiac output can also be estimated.
Pericardial effusion: fluid in the pericardial cavity shows as an echo-free region between the myocardium and the intense echo of the parietal pericardium.
Ischaemic disease: coronary arteries cannot be imaged adequately using echo techniques but images maybe useful for diagnosis of complications related to myocardial infarction.
Quantification of left ventricular function: heart failure maybe due to systolic or diastolic ventricular impairment or both. Echo helps by measuring end diastolic volume. If this is large, systolic dysfunction is most likely.
( the above are just brief descriptions of how ECG may be used clinically, for more details please refer to KUMAR AND CLARKE, clinical medicine p749-755)