Developmental Pathophysiology, Develop. Physiol., Dr. D. Penney
Table 4.14 - Characteristics of Atrial Septal Defects.
- Large ASD gives a common filling pressure for both ventricles.
- As RV wall thins, L --> R shunt develops, producing dilatation of RA, RV & pulmonary vessels; seen on ECG, chest X-ray, & echocardiography.
- ASD is silent! However, increased flow through tricuspid valve gives a mid-diastolic rumbling murmur, and a systolic ejection murmur due to increased pulmonary valve flow (fixed wide-split S2).
- O2 step-up at atrial level by cardiac catheterization permits calculation of shunt flow.
|RV||20, 70%||40, 85%|
| PA ||20||30|
| svc ||70%||70%|
| LV ||100||100|
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