Wed 28 March 2018
The value of mitral valve repair is well established, with results in experienced hands demonstrating longer term durability than with pig or cow valves. Repair also preserves cardiac function.
For some unkown reason, aortic valve repair has not been so readily adopted by surgeons despite the fact that the results of such an approach can yield excellent long-term results in certain circumstances.
In patients with aneurysmal swelling of the aorta pipe as it emerges from the heart (the aortic root), the aortic valve can often be found to be structurally normal with either no leakage at all or with leakage related to separation of the valve leaflets as a result of aortic dilatation. In this condition, many surgeons will replace the aortic aneurysm and the aortic valve all in one. This is not always advantageous especially when aortic valve preservation is possible.
Aortic valve preserving aortic root replacement involves substituting the swollen aortic root, with a man-made graft called Dacron. This is essential to prevent further aneurysm formation later in life. Instead of replacing the aortic valve the valve is re-suspended inside the Dacron graft. By correcting the ring upon which the aortic valve hangs, the surgeon effectively preserves the normal aortic valve and also corrects any abnormal leakage. This procedure is called a David Procedure and is well recognised throughout the world, but is not widely practised becuse of the skill required to perform the procedure.
The durability of this approach of aortic valve preservation in aortic root aneurysm disease is excellent with preserved function in more than 95% of cases at 10 years in many published series. This is far better than tissue valve durability and the patient can also avoid the need for the warfarin which is required when replacing valves with mechanical devices. One other advantage of repair is the superior haemodynamic function compared to replacement.
We prefer to perform David procedures in aortic root disease and use keyhole incisions whenever possible.
In a recent study, David Procedures performed via full breastbone cuts were compared with those performed using keyhole heart surgery. It is gratifying to see that the results of this procedure performed through keyhole cuts at 5 and 10 years was not compromised by the smaller cuts used in keyhole heart surgery. There is no doubt though that this outcome has been achieved as a result of sustained clinical experience in the arena of aortic valve preservation and minimally invasive cuts. We look forward to continuing to identify patients suitable for aortic valve preservation using keyhole heart surgery.