What is the classic murmur associated with ventricular septal defect (VSD)?

The classic murmur associated with a ventricular septal defect (VSD) is a harsh holosystolic murmur. This type of murmur occurs throughout the entire duration of systole due to the abnormal flow of blood from the left ventricle into the right ventricle as a result of the septal defect. The turbulent flow produced by this left-to-right shunt creates a distinct sound that is described as harsh.

In clinical practice, this murmur is typically best heard at the left lower sternal border and can increase in intensity depending on the size of the defect and the volume of blood flowing through it. Its characterization as "holosystolic" emphasizes that it starts at the first heart sound and persists until the second heart sound, making it a critical finding in the evaluation of a patient suspected to have VSD.

Other murmurs listed are associated with different types of cardiac conditions. For instance, a soft diastolic murmur is often associated with conditions like aortic regurgitation, while a high-pitched systolic murmur may be seen in conditions like hypertrophic cardiomyopathy. Continuous murmurs often indicate abnormal blood flow in conditions such as patent ductus arteriosus. Understanding these distinctions is