Question

are individuals able to detect the slight lag between the closure of the mitral and tricuspid valves? why or why not?

Answer 1

In most of the cases ( about 40-70% ) the slight lag between the closure of mitral and tricuspid valve can be detected .

Due to the electrical conductions of the heart, left ventricle contracts slightly before the right ventricle so the mitral valve closes slightly before the tricuspid valve.Closure of mitral and tricuspid valve is known as first heart sound, S1.

Since mitral valve transmits widely , it can be heard throughout entire precordium but tricuspid valve sound can only be heard in tricuspid area (in 0.02-0.03sec difference) after the closure of mitral valve. S1 can be best heard over the cardiac apex , using a stethoscope.

The two sounds heard is known as M1- T1 which is best heard at the left sternal border with stethoscope diaphragm.