Health Information

Systolic murmur is produced in the following conditions

Incompetence of Atrioventricular Valves

When the atrioventricular valves become weak, these valves cannot close completely. This causes regurgitation of blood from ventricles to the atria during ventricular systole producing the murmur. It is a harsh blowing sound with high frequency.

Stenosis of Semilunar Valves

During stenosis of aortic valve, the left ventricular pressure raises up to 300 nm Hg during systole. This causes a greater turbulence in blood. The vibrations of this sound can be felt as ‘thrills’ by palpation over lower neck region and upper chest. When the disease is very severe, the sound is heard even a few feet away from the affected person. This is a harsh and loud sound.

Murmur due to Anemia

A systolic murmur is heard in severe anemia because of reduced viscosity and accelerated flow of blood.

Septal Defect

A systolic murmur is produced in the interventricular septal defect as it causes flow of blood from left ventricle to right ventricle. The murmur due to interatrial septal defect is rare.

Coarctation of Aorta

This is a congenital disorder characterized by the narrowing of a part of systemic aorta. A loud murmur produced during systole is heard during the earlier part of diastole also.

Diastolic Murmur

The diastolic murmur occurs in the following conditions

Stenosis of Atrioventricular Valves

When the atrioventricular valves become narrow, the turbulence of blood flow occurs during diastole, i.e. when the blood enters the ventricles from atria. Murmur due to stenosis of mitral valve in heard better at apex beat area. The murmur due to the stenosis of tricuspid valve is heard best at tricuspid area. This is a weak sound with low frequency.

Sometimes, the murmur due to mitral stenosis cannot be heard by the stethoscope due to low frequency. But it can be felt as a mild thrill over apex beat area of the chest.

Incompetence of Semilunar Valves

This is produced due to regurgitation of blood from aorta into the ventricle through the incompetent Semilunar valve during diastole. This is a blowing sound with low frequency