Prosthetic Conduits

Increased recognition of ascending thoracic aortic disease has recently occurred through heightened clinical awareness and improved invasive and nonin­vasive detection techniques. The use of composite graft valve conduits has become an increasingly ac­cepted surgical procedure to replace certain aortic root aneurysms and to manage acute and chronic ascending aortic dissections. Confidence in this tech­nique has led to a more aggressive approach with earlier case selection in an effort to avoid the conse­quences of rupture, dissections and aortic regurgita­tion.

Since 1968 when Bentall and DeBono first de­scribed the use of the composite aortic valve conduit replacement of the ascending aorta and aortic valve, the operation has become quite common. Postopera­tive complications have ranged from 10 to 27 percent. Gott et al described a 10.2 percent overall mortality (six patients) among 50 Marfans syndrome patients who had composite valve conduits placed for ascend­ing aortic aneurysm with associated aortic regurgita­tion and decreased left ventricular function. Two deaths were attributed to dysrhythmia, two from late endocarditis and one from a ruptured abdominal aortic aneurysm. One in-hospital death occurred in a patient with acute ascending aortic dissection who could not be separated from cardiopulmonary bypass. Based on their results, Gott et al have recommended elective composite graft replacement when an ascending aortic aneurysm reaches 6 cm even if no hemodynamic or other clinical compromise has occurred. Helseth et al report a series of 41 patients who underwent compos­ite graft valve replacement for ascending aortic disease with 40 patients (97.5 percent) having long-term survival. In a follow-up of nearly eight years, no patient has exhibited conduit malfunction, evidence of coro­nary artery ostial stenosis or pseudoaneurysm forma­tion. Approximately two thirds of the patients had follow-up aortography at six months to one year. Two patients died late, one 51/2 years postoperatively of a ruptured abdominal aortic aneurysm and one of a ruptured intracerebral aneurysm 18 months following the operation. Kouchoukos et al also support the use of composite graft replacement of the ascending aorta and aortic valve. None of the 73 patients surviving surgery of the type described in this study required reoperation for compression of the graft resulting from hematoma between the graft and the aortic wall. Postoperative aortograms were performed in only 15 patients with pseudoaneurysms of the coronary ostia observed in four and at the distal anastomosis in one. cialis super active

Marvasti et al recently reported 30 patients who had replacement of the ascending aorta and aortic valve with a composite graft. Pseudoaneurysms were found in four of 15 unselected patients at one or more suture lines by digital subtraction angiography. These authors suggest angiography within a few months after operation in those who undergo this operative tech­nique. In fact, Kouchoukos now recommends angi­ography be performed prior to hospital discharge in all patients who have the native aorta wrapped around the composite graft.