Total Anomalous Pulmonary Venous Connection with Rare Direct Right Atrial Drainage and Unprecedented Array of Coexistent Multisystem Variations.

Total anomalous pulmonary venous connection (TAPVC) is anomalous drainage of all pulmonary veins into systemic circulation. The intracardiac type typically entails the drainage of all the pulmonary veins into the right atrium, via the coronary sinus. The connection of the pulmonary veins directly into the right atrium is exceptionally rare and has been primarily reported with right atrial isomerism. Herein, we presented a remarkable case of TAPVC in a 10-year-old male child, distinguished by an unconventional drainage of all the pulmonary veins directly into the right atrium, with normal coronary sinus and absent right atrial isomerism. Intriguingly, computed tomography imaging revealed a combination of incredibly rare coexistent pulmonary, vascular, and skeletal anomalies. These anomalies included absence of pulmonary fissures in the right lung, presence of left circumflex aortic arch with bovine branching pattern, bilateral cervical ribs, and C7 vertebral fusion anomalies. To our knowledge, this unique combination of coexistent anomalies has not been previously reported in scientific literature in the background of rare drainage pattern of TAPVC.