What is a "heart click"?

A heart sound: The normal heart has usually 2 predominant sounds s1 and s2 (racepinephrine) which are the closing of the mitral and tricuspid valves and then closing of the aortic and pulmonary valves. A click is another sound often associated with the sudden opening of a stiff aortic or pulmonary valve. It is usually associated with a murmur.

Abnormal heart sound: Most commonly a click is a sound made by mitral valve prolapse. Other causess would be an ejection click from aortic stenosis or pulmonary stenosis.