ABSTRACT

The technique of root inclusion was first described by O’Brien for the implantation of homografts.1 The root inclusion technique for stentless bioprostheses has some important advantages over the most widely used subcoronary implant technique and also over the root replacement technique. In root inclusion a ring of prosthesis aortic wall, including the sinotubular junction, just above the tops of the commissures, is preserved, thereby maintaining distances between the tops of the commissures exactly at their original length. This is essential to obtain normal loading of the valve leaflets with normal stresses and strains, as described by us earlier.2 Normal loading of the leaflets is probably one of the most important factors for durability of the valve. This also explains the better durability of a stentless valve as compared with a stented valve.3,4 Especially in a dilated aortic root, root replacement and root inclusion are the only methods to preserve completely the original geometry of the valve, in contrast to the subcoronary implant technique, with which this is very difficult. Root inclusion gives less risk of postoperative bleeding because, in contrast to the root replacement technique, only one suture line is exposed to the pericardium. The aortic wall part of the porcine bioprosthesis will probably calcify in the course of time; this might make a reoperation, if needed, very difficult. With root inclusion the porcine aorta is protected by the patient’s aorta, which will probably make reoperation easier. The disadvantage of the root inclusion technique is that it is more difficult than the subcoronary and root replacement techniques and therefore may need somewhat longer cross-clamp times.