Pansystolic murmur starts immediately with first heart sound and continuous through to the second heart sound. Pansystolic murmur has different causes. The various different causes which are responsible for causing pansystolic murmur are as follow-
1. Mitral regurgitation.
2. Tricuspid regurgitation.
3. Ventricular septal defect.
4. Aorto-pulmonary shunts.
1. Mitral regurgitation-
Mitral regurgitation has high pitched, blowing, pansystolic murmur heard at the apex which radiates to axilla and back in case of anterior mitral leaflet involvement. Whereas in case of posterior mitral leaflet involvement, pansystolic murmur radiates to left sternal border and base of the heart. It increases during expiration and
2. Tricuspid regurgitation-
In tricuspid regurgitation, there is blowing pansystolic murmur heard at lower left sternal border radiating
In tricuspid regurgitation, pansystolic murmur gets increased during inspiration whereas in mitral regurgitation it increases during expiration. Hepatomegaly is present there in tricuspid regurgitation along with pulmonary hypertension.
3. Ventricular septal defect-
In ventricular septal defect, there is harsh pansystolic murmur heard at the third or fourth left intercostal space radiating all over precordium. In ventricular septal defect murmur increases during transient exercise but there is no effect of respiration on murmur.
4. Aorto-pulmonary shunts- which is very rare.
Reference- Book- Practice of Medicine by Davidson