Large Calibre Self-Expanding Stents for Pulmonary Stenosis After the Arterial Switch, a Low-Risk Solution to a Low-Flow Situation.

Branch pulmonary artery stenosis is one of the most common complications late after the arterial switch operation. The pathophysiology of stenosis in these circumstances is very different to that encountered in with normally related great vessels. The LeCompte manoeuvre leaves the pulmonary arteries straddled and stretched over the aortic root which contributing significantly to the degree of stenosis encountered. Unilateral branch pulmonary artery stenosis rarely leads to significant symptoms in young patients with biventricular repairs; however, significant discrepancies in the split flows between right and left lung may place the patient in an unfavourable physiological position as they move in to middle age. Balloon expandable stent implantation distorts the anatomical arrangement of the LeCompte and is associated with negative interactions with the often dilated aortic root. We present three cases of the use of flexible self-expanding stents to improve the physiological flow distributions to each lung whilst hopefully decreasing the risk of erosion and perforation or fistula formation related to the pulmonary artery. All three patients had uncomplicated procedures with significant improvements in vessel diameter and flow distribution noted on follow-up MRI scans. This is the first report of the use of self-expanding stents in the context of branch pulmonary artery stenosis after the LeCompte manoeuvre. Theoretically and based on our early experience, this technique provides potential safety advantages over the use of more traditional balloon expandable stents.