Transition from fetal to extrauterine circulation

Area of Science:

• Cardiology
• Neonatal Physiology
• Developmental Biology

Background:

• Fetal circulation is characterized by high pulmonary vascular resistance and right-to-left shunting.
• Key structures like the ductus arteriosus and foramen ovale facilitate fetal blood flow.
• Transition to neonatal circulation involves significant cardiopulmonary adjustments at birth.

Purpose of the Study:

• To review the characteristics of fetal circulation.
• To describe the transition from fetal to neonatal circulation.
• To discuss the impact of disrupted transition and its link to congenital heart disease.

Main Methods:

• Review of existing literature on fetal and neonatal cardiopulmonary physiology.
• Analysis of the anatomical and biochemical changes during the transition period.
• Correlation of fetal cardiopulmonary anatomy with congenital heart disease.

Main Results:

• Fetal circulation prioritizes placental gas exchange over lung perfusion.
• Delivery necessitates rapid changes in pulmonary vascular resistance and circulatory pathways.
• Abnormalities in this transition are associated with various congenital heart defects.

Conclusions:

• Understanding fetal circulation is crucial for recognizing neonatal cardiopulmonary adaptation.
• Disruptions in the transition process can lead to significant health issues.
• Knowledge of fetal cardiopulmonary anatomy aids in diagnosing and managing congenital heart disease.