Obstructions can occur at various levels in the right side of the heart or in the pulmonary outflow path. Pure obstructions do not result in a mixing of the blood but cause a massive additional strain on the ventricles because they have to pump against increased resistance.
In cardiac abnormalities with right-left shunts oxygen-poor blood gets from the right half of the heart into the left side and thus into the systemic circulatory system. In most of the defects with right-left shunts the physiologic shunts present before birth remain functional because no reversal of pressure happens following birth.
Case studies involving the thorax, mediastinum, embryology of the heart & circulatory systems
Anatomic and clinical reviews that will include basic symptoms and findings, diagnosis & treatment
Tufts University school of Medicine
Joan F. Tryzelaar, M.D., F.A.C.S, F.A.C.C.P.
Before we go on to congenital heart problems, it is good to review how to get into the chest:
You have just been invited to participate in an operation. The surgeon plans a posterolateral thoracotomy to enter the chest. He will tell you that he plans entry via the 6th intercostals interspace(Pearl: found two finger widths below the tip of the scapula).