Development of a simple device enabling percutaneous flow regulation for a small vascular graft for a Blalock–Taussig shunt capable of flow regulation: complete translation of an original article originally published in Pediatric Cardiology and Cardiac Surgery (154–159, 2016: vol. 32).

Abstract

The Blalock-Taussig shunt (BTS) operation is a cornerstone as initial palliative surgery for congenital heart disease with severely reduced pulmonary blood flow (PBF). The ideal PBF provided by BTS is crucial for an uneventful postoperative course, since excess PBF results in acute distress of the systemic circulation and insufficient PBF requires another BTS surgery. Therefore, the goal of this study was to develop a simple device to control the shunt graft flow percutaneously using a constrictor balloon connected to a subcutaneous port. The device consists of a cylindrical balloon and an anti-bending structure extension connected to the balloon center. A PTFE vascular graft wrapped by the device was connected to a simulated closed circuit to measure the relationship between pressure and blood flow while changing the inner volume of the balloon. In a beagle model of replacement of the right carotid artery, blood flow velocity was measured in the carotid artery after saline injection into the balloon. The blood flow velocity before and after balloon inflation was compared immediately after implantation of the device and at 3 months after implantation. The device provided good flow control by inflating and deflating the balloon ex vivo and in vivo for up to 3 months in a canine model with a small graft wrapped with the device. The simple device developed in this study may enable regulation of PBF through a small vascular graft and help to prevent severe morbidity and mortality in the clinical setting of BTS.