Реферат: Heart Essay Research Paper HEARTThe human heart

when the valves are abnormal. Some heart murmurs, however, may also occur in healthy persons, mainly

during rapid or pronounced cardiac action. The study of heart sounds and murmurs furnishes valuable

information regarding the condition of the heart muscle and valves. The heart sounds are recorded with

the aid of sensitive microphones (phonocardiography), so that anomalies of the heart or the valves can be

analyzed. The conduction of the contraction stimulus can!

also be recorded on the body surface by an ELECTROCARDIOGRAPH. This measures the differences in

potential (in microvolts) that exist between a number of fixed points on the limbs and the chest wall.

The electrocardiogram (cardiogram, ECG) that is obtained in this way furnishes information about the

rhythm of the heart, the conduction of the stimulus, and the condition of the heart muscle. Other methods

that have been devised to examine the heart are the mechanical recording of the heartbeat,

echocendiography and radioisotopes, X-ray analysis of the heart’s form and movements, and X-ray contrast

studies of the blood flow through the heart and the coronary vessels.