**8.1 Partial AVSD**

Usually, patients with partial AV septal defect (also called primum ASD) remain asymptomatic until early childhood. They rarely present early with failure to thrive depending on the size of the defect and severity of AV valve regurgitation. Patients with primum ASDs usually present earlier and with symptoms when compared with secundum ASDs. Auscultatory findings include widely split and fixed second heart

### **Figure 8.**

*2D echocardiogram apical 4-chamber view: Complete balanced AVSD. A. When AV valve is closed, there is large primum atrial septal defect (ASD, \*) and large inlet ventricular septal defect (VSD, +). Common AV valve and single orifice. B. with valve open. RA, right atrium; LA, left atrium; RV, right ventricle; LV, left ventricle.*

#### **Figure 9.**

*Transesophageal echocardiogram, four-chamber view. A. Partial AVSD with large primum atrial septal defect (ASD) (\*). Note the valvar attachments to crest of the septum. B. Transitional AVSD with small primum ASD and inlet ventricular septal defect (+) covered by right AVV chordal attachments to the crest of ventricular septum. RA, right atrium; LA, left atrium; RV, right ventricle; LV, left ventricle.*

sound, crescendo- decrescendo systolic ejection murmur at the left upper sternal border from the increased flow across pulmonary valve, and holosystolic murmur at the apex from LAVV regurgitation. A mid-diastolic murmur may be heard at the apex if there is significant mitral regurgitation or at the left lower sternal border if there is a large atrial shunt.

### **8.2 Complete AVSD**

Patients with complete AV septal defects present in the neonatal period after first few days/weeks of life when pulmonary vascular resistance falls. This is attributed to the large atrial and ventricular level shunts leading to pulmonary over circulation. There will be tachypnea, increased work of breathing, failure to gain weight. More often, they would require high-calorie nutrition, diuretics to decrease the preload. On exam, there will be accentuated first heart sound, with S1- coincident holosystolic murmur from LAVV regurgitation, widely split and fixed S2, crescendo- decrescendo systolic ejection murmur at the left upper sternal border from the increased flow across pulmonary valve and sometimes mid-diastolic murmur at apex.
