Ejection click in pulmonary stenosis – Medicine MCQ

Ejection click in pulmonary stenosis is:
a) Better heard in expiration
b) Better heard in inspiration
c) No change with respiration
d) None of the above

Correct answer: a) Better heard in expiration

The ejection click in pulmonary stenosis occurs when the stiff valve opens.
It varies with respiration and is better heard in expiration.
It is usually seen in association with post stenotic dilatation of the pulmonary artery.

Mechanism of respiratory variation of ejection click in pulmonary stenosis

During inspiration, the increased venous return results in an increase in right ventricular end diastolic volume
This in turn results in pushing up of the pulmonary valve leaflets
Hence, when the valve opens during ventricular systole, the excursion of the valve leaflets is reduced
But during expiration, the venous return is decreased and the end diastolic volume is lower
The valve leaflets do not get pushed up
Hence, during systole, the valve leaflets have to move a greater distance resulting in the production of a prominent click

Read more about phasic ejection click : https://cardiophile.org/phasic-ejection-click/