Surgical repair of aorto-left ventricular tunnel (a) and aorto-right ventricular tunnel (b). The aortic orifice of either tunnel is closed with a patch inserted through an aortotomy. A left ventricular orifice is closed with a second patch, placed through the opened tunnel itself, which is then obliterated by reapproximation of its walls over the patch. The upper margin of this second patch attaches to the extra-luminal surface of the first. In the case of aorto-right ventricular tunnel, the right ventricular orifice is approached through the right ventricle or pulmonary valve, and the second patch lies completely separate from that in the aorta.