Enlargement of the Aortic Annulus During Aortic Valve Replacement: A Still Unresolved Conundrum

Enlargement of the aortic annulus (EAA) during aortic valve replacement represents an established method to implant a prosthesis of a larger size than the original annulus, to avoid prosthesis-patient mismatch. Nevertheless, there is still considerable controversy regarding the need for and effectiveness of this procedure. In The Annals of Thoracic Surgery, Mehaffey and colleagues1 reported the short-term and long-term outcomes of EAA in an elderly population in the United States. We have been particularly interested in this survey, especially considering the conclusions reached indicating an increased risk in patients undergoing EAA and how EAA is performed in a limited number of patients aged 65 years and older. Indeed, many currently available bioprostheses, whether stented, stentless, sutureless, rapid deployment, or devices for transcatheter implantation, provide excellent hemodynamic performance that is generally adequate for elderly patients. Therefore, in this specific subset, the fact that EAA is rarely carried out is not surprising. Nevertheless, the article by Mehaffey and colleagues1 overlooks a point of crucial importance. The specific techniques used for EAA are, in fact, not mentioned, and this has a major impact on the size of the prosthesis that can fit the “enlarged” annulus. Indeed, since the early 1970s, various techniques have been described to obtain EAA, but some of them, such as the original technique proposed by Nicks and colleagues, do not provide any EAA but rather enlargement of only the aortic root, with consequent limited efficacy. Furthermore, our experience with a simplified technique, using a patch of bovine pericardium in a series of patients with a mean age of 68 years, indicates that EAA can be performed with low mortality, without a significant increase of the ischemic time, and with stable results approaching the second decade of follow-up. Certainly, our data will not stop the ongoing debate on EAA, but we hope that they will help to revitalize a seemingly obsolete technique that should be maintained in the cardiac surgery armamentarium.