Right atrial and tricuspid hypoplasia

Area of Science:

• Cardiology
• Developmental Biology
• Medical Genetics

Background:

• Cor triatriatum dexter is a rare congenital heart anomaly characterized by the division of the right atrium into sinus and primitive portions.
• It is hypothesized that incomplete regression of embryonic venous valves leads to abnormal fetal circulation and right heart maldevelopment.
• While right ventricular underdevelopment and tricuspid valve abnormalities are known, right atrial hypoplasia with tricuspid hypoplasia due to multiple venous valves is exceptionally rare.

Observation:

• This report details a complex case of cor triatriatum dexter.
• The patient presented with a hypoplastic, tubular right atrium formed by the superior and inferior vena cava.
• The anomalous atrium was further divided into three compartments by two septal membranes.

Findings:

• The case illustrates an extremely rare manifestation of cor triatriatum dexter.
• The findings highlight the potential for multiple venous valve remnants to cause significant right atrial hypoplasia and associated tricuspid valve underdevelopment.
• This complex anatomy underscores the intricate developmental processes of the fetal heart.

Implications:

• This case expands the understanding of the spectrum of cor triatriatum dexter and its embryological basis.
• It emphasizes the importance of recognizing rare cardiac anomalies for accurate diagnosis and management.
• Further research into the genetic and developmental factors influencing venous valve regression may elucidate mechanisms for such complex congenital heart defects.