Catheter interventional closure of veno-venous collaterals in cyanotic patients after partial cavopulmonary shunts in pediatric patients: clinical practice review

The development of veno-venous collaterals is an important and treatable cause of cyanosis in patients who had undergone partial cavo-pulmonary connection (PCPC) operations. Nevertheless, the literature on this complicated therapeutic option is sparse. Patients can present cyanosis either immediately after the operation (<30 days), which delays or hinders discharge from the intensive care unit or cyanosis may occur late: (>30 days and/or in another hospital admission), after the operation. Hence, transcatheter closure of veno-venous collaterals is the treatment of choice. Four patients were selected who showed cyanosis at variable durations after PCPC; the morphology of the collaterals and their hemodynamic effect was described and the strategy for closure of such abnormal vessels is suggested. Veno-venous collaterals described in our series were seen originating mainly or mostly from innominate vein angles. The drainage sites were either above the diaphragm into a cardiac structure: the coronary sinus (CS) and/or atria; or below the diaphragm into the inferior vena cava (IVC) or hepatic veins through the paravertebral venous system and/or the azygous system. It is stated in the literature that several types of devices and coils can be used to close the collaterals such as the Amplatzer vascular plugs (AVPs), Amplatzer duct occluder II (ADOII), non-detachable and detachable coils. In this clinical review, the technical details that determine device type and size are explained. The recent generations of hydrogel-coated coils were also used in this series of patients to close the difficult types of collaterals with better results. All described vessels were closed successfully, without any complications. The patients had a significant rise in their transcutaneous oxygen saturations and hence, a clear clinical benefit.