Heart Murmur Characteristics of Ventricular Septal Defect

Ventricular septal defect (VSD) is one of the most common congenital heart abnormalities. It can occur as an isolated condition or in combination with other cardiac anomalies. Due to the left-to-right shunting at the ventricular level, patients with VSD often present with heart murmurs. The specific characteristics of these murmurs depend on the size and type of the defect—classified as small, moderate, or large VSD.

Types of VSD and Associated Murmur Features

Small Ventricular Septal Defect

In patients with a small VSD, a loud and harsh pansystolic murmur of grade IV to VI is typically heard along the lower left sternal border, specifically at the third to fourth intercostal space. This murmur is often accompanied by a palpable thrill. Additionally, the second heart sound (P2) may exhibit mild splitting due to increased pulmonary artery pressure.

Moderate Ventricular Septal Defect

With a moderate-sized VSD, the pansystolic murmur remains prominent along the left sternal border and may still be associated with a thrill. However, a mid-diastolic regurgitant murmur may also be audible at the cardiac apex. This is usually due to increased flow across the mitral valve. The P2 component of the second heart sound becomes more pronounced, indicating elevated pulmonary artery pressures.

Large Ventricular Septal Defect

In cases of large VSD, the systolic murmur along the left sternal border may decrease in intensity, often grading around III. The P2 sound becomes significantly accentuated, reflecting substantial pulmonary hypertension. In some cases, a diastolic murmur may also be detected, suggesting volume overload in the right ventricle.

Treatment and Medical Intervention

If patients experience symptoms or complications related to VSD, it is essential to seek evaluation from a qualified cardiologist. Depending on the severity and clinical presentation, treatment options may include surgical repair or transcatheter closure of the defect. Early diagnosis and appropriate management are crucial in preventing long-term complications such as heart failure or pulmonary hypertension.