Atrial Septal Defect (ASD)
Definition
3 types:
Natural history
Epidemiology
Clinical Features
Symptoms
Signs
Investigations
Bedside:
Treatment
Complications
Source
Toronto Notes 2012
3 types:
- Ostium primum (common in Down syndrome)
- Ostium secundum (most common type, 50-70% )
- Sinus venosus (defect located at entry of superior vena cava into right atrium)
Natural history
- 80-100% spontaneous closure rate if ASD diameter <8 mm
Epidemiology
- 6-8% of congenital heart lesions
Clinical Features
Symptoms
- Often asymptomatic
Signs
- Grade 2-3/6 pulmonic outflow murmur (SEM)
- Mid-diastolic rumble at the left lower sternal border
- Widely split and fixed S2
Investigations
Bedside:
- ECG: right axis deviation (RAD), mild RVH, right bundle branch block (RBBB)
- CXR: increased pulmonary vasculature
Treatment
- Elective surgical/catheter closure
Complications
- CHF
- Pulmonary hypertension
Source
Toronto Notes 2012