Fig. 12.1a
The aneurysmal ascending aorta is removed from 10 mm above the coronary ostia to the normal distal ascending aorta
Fig. 12.1b
Coronary ostia are detached as large buttons with the aortic wall. Aortic valve is removed
Fig. 12.1c
Composite graft. A mechanical valve is fixed in the tube graft
Two holes are made in the composite graft at the positions of the coronary ostia. Originally, coronary ostia were approximated to the graft and directly sutured to the holes of the graft. This method might cause significant tension to suture lines and bleeding, so that many modifications have been developed.
Nowadays, coronary ostia are detached as large buttons of the aortic wall and dissected free along their courses to ensure their mobility. The scalloped coronary buttons are sutured to the holes of the aortic graft directly (Carrel patch method) or interposing a small graft (Piehler method) (Fig. 12.1d).
Fig. 12.1d
Ascending aorta is replaced with a composite graft. Coronary ostium is reimplanted to the graft directly (Carrel patch method) or interposing a small graft (Piehler method)
The Bentall operation is usually indicated in AAE with a diseased aortic valve.
Aortic aneurysms in the patients with Marfan syndrome are also repaired with this technique. Marfan syndrome is frequently associated with aortic dissection. Depending on the location and extent of the dissection, additional reconstruction or replacement of other parts of the aorta is necessary.
A large aorta is frequently observed in TOF, especially in the case of tetralogy of Fallot (TOF) with pulmonary atresia. Niwa [5] reported that 15 % of repaired adults with TOF had a dilated aortic root (Figs. 12.2a, 12.2b, and 12.2c).
Fig. 12.2a
Aortogram of a 46-year-old male who underwent TOF repair 41 years ago. Three years after pulmonary valve replacement at 43 year of age, aortic dilatation and aortic regurgitation were rapidly developed
Fig. 12.2b
Marked aortic dilation of the patient. Left is the cranial side
Fig. 12.2c
Aneurysmal ascending aorta was replaced aortic a composite graft
Fortunately, only a small number of these patients seem to develop an aortic dissection [5]. For this reason, aortic replacement in TOF is indicated at a later stage compared to patients who developed an aortic aneurysm in other anomalies. However, when the diameter of the aortic root excesses 55 mm [6, 7], aortic replacement could be considered. If significant aortic regurgitation occurs due to annular dilatation, aortic valve replacement (AVR) combined with ascending aortic replacement or Bentall operation would be indicated.
12.2.1 Valve-Sparing Operation
Among patients with aortic dilatation, severe AR may occur only due to annular dilatation. When the aortic valve is not affected, it may be feasible to recover competence of the aortic valve by reducing the diameter of the aortic annulus and the suspension of cusps. Based on this concept, valve-sparing root replacement had been developed by Yacoub in 1979 (remodeling method [2]) and by David in 1992 (reimplantation method [3]).
12.2.1.1 Remodeling Method
Cardiopulmonary bypass is established in the same manner as in the Bentall operation. The aneurysmal ascending aorta is removed from the distal portion to the sinus of Valsalva. The coronary ostia are detached from the aortic wall as large buttons. The sinus of Valsalva is resected, whereas the aortic valve is preserved. A proper size tube graft, usually determined by the diameter of the sino-tubular junction at the time of competent approximation of the cusps, is prepared to fit the shape of the Valsalva sinuses and is sutured to the wall of the sinuses. As in the Bentall operation, two holes are made in the tube graft at the corresponding positions of the coronary ostia (Fig. 12.3). The coronary buttons are sutured to the tube graft in the same way as in the Bentall operation. Since the aortic annulus is untouched in the remodeling method, aortic root dilation may develop.
Fig. 12.3
Completion of remodeling method. Aneurysmal ascending aorta is removed to Valsalva sinuses. Coronary ostia are removed as large buttons. A proper size tube graft is trimmed to fit the figure of Valsalva sinuses. The ascending aorta is replaced with this graft. Coronary ostia are reimplanted to the tube graft
12.2.1.2 Reimplantation Method
Preservation of the aortic valve and enucleation of coronary buttons are performed in the same manner as in the remodeling method. A tube graft of 4-5 mm larger than the diameter of the aortic annulus is selected. The first row sutures are placed inside to outside just below the aortic cusps to fix the tube graft. Commissural walls are pulled into a tube graft (Fig. 12.4a), and then first row sutures are put in the edge of the graft and tied down. Each commissural wall is suspended to the inside of the tube graft arranging competence of the aortic valve. The free edge of the Valsalva sinuses is sutured continuously to the inside of the tube graft (second row sutures) (Fig. 12.4b). Two holes are made in the tube graft at the positions of the corresponding coronary ostia. The coronary buttons are sutured to the tube graft in the same fashion as in other forms of root replacement (Fig. 12.4c). This method is particularly indicated in young female with Marfan syndrome (Fig. 12.5). Although often a straight tube graft is used for root replacement, also a new type of grafts with a bulged midportion for improvement of valve movement is utilized.
