The size of a Ventricular Septal Defect (VSD) is categorized relative to the diameter of the aortic annulus, a key structure in the heart.
VSDs aren't simply measured in millimeters; instead, their size is classified based on their proportion to the aortic annulus diameter. This helps doctors understand the potential impact of the defect on heart function. The classification is as follows:
- Small VSD: A VSD is considered small if its diameter is equal to or less than 25% of the aortic annulus diameter. Small VSDs often close on their own and may not require treatment.
- Medium VSD: A VSD is considered medium if its diameter is more than 25% but less than 75% of the aortic annulus diameter. These VSDs may cause noticeable symptoms and often require medical intervention.
- Large VSD: A VSD is considered large if its diameter exceeds 75% of the aortic annulus diameter. Large VSDs can lead to significant heart problems and typically require surgical repair.
In essence, defining VSD size relies on proportional measurement relative to the aortic annulus, helping clinicians assess the severity and determine the appropriate course of action.
