High Reimplantation of Coronary Arteries After the Switch Procedure and Associated Stenoses

Surgical repair through the arterial switch operation (ASO) is the only definitive treatment in patients with dextro-transposition of the great arteries (d-TGA). A crucial step during the reimplantation process is transfer of coronary arteries (CA) to the neo-aorta. A potential cause of CA stenosis is the presence of a high implantation of CA (HICA), defined by the presence of coronary ostium located above the sinotubular junction (STJ) of the aorta. We conducted a retrospective study on 157 patients (82 had digitally preserved angiograms) with d-TGA between 2010 and 2018 in a tertiary pediatric hospital in Canada. Of the 82 cases, 56 (68%) had HICA above the STJ. The mean distance from the STJ was + 7.1 ± 3.4 mm for the RCA, and + 6.8 ± 3.1 mm for the LMCA. Out of the 56 patients with HICA, 4 patients (7%) had stenosis, and out of 26 patients with in-sinus reimplanted CA, one patient (4%) had stenosis (p = 0.16). Patients in the HICA group with stenosis had a lower height of reimplantation of the CA compared to those without stenosis (+ 4.5 ± 1.3 mm vs. + 6.8 ± 3.1 mm, respectively; p < 0.05). This is a rare study assessing the rates of stenosis in the context of in-sinus versus HICA in the ASO. Reimplanting the coronary ostia at a higher level than the expected natural level does not seem to be associated with a significant risk in compromising CA perfusion.