Question

If the heart sound recording and the ECO recording are superimposed then the first heart sound would occur
A. At the P wave
B.Just after the P wave
C. Just before the QRS complex
D. Just after the QRS complex.

Answer 1

The heart sound recording is done using a computer-based monitor called the Heart sound recorder. It uses the technique of auscultation where the internal sound of the body can be listened using a stethoscope. This device helps to monitor the heart's reaction to certain stress where the rhythm, tone, rate of the heartbeat of the heart cycles are noted on the graph.

Complete step by step answer:
-Echo is defined as the Echocardiogram. This technique uses the sound waves to study the heart structure and working of valves.
-Each cardiac cycle produces three types of waves P, QRS, T.
-P wave is the small upward deflection. It represents the atrial contraction.
-QRS complex represents the onset of contraction of ventricles.
-T wave represents ventricular depolarization or end of ventricular contraction.
-The heartbeat can listen as lub -dub which is as a result of the closing of tricuspid,bicuspid and semilunar valves respectively.
-The lub is low pitched and it is for a short period whereas the dub sound is very loud and it is for a short period.
-The QRS wave corresponds to the ventricular systole and it gives the peak.
-If the heart sound recording and the ECO recording are superimposed then the first heart sound would occur just after the QRS complex.
So, the correct answer is option (D) Just after the QRS complex.

Note: The human heart usually beats 72 times in a minute. Two sounds are produced at the time of its beating namely lub and dub sounds. The first sound that is lub is heard on the closing of tricuspid and bicuspid valves. These valves are closed during the ventricular contraction which is heard only after the QRS complex.