Mitral Valve Repair: What the ACORN Trial Taught Us

Abstract

Progressive left ventricular remodeling is characterized by dilation of the left ventricle with a change in the heart from an elliptical shape to a more spherical shape. This change is part of the unfavorable natural history in patients with heart failure. The CorCap Cardiac Support Device (Acorn Cardiovascular, St. Paul, MN) is a mesh device that is implanted around the heart to reduce wall stress and the first therapy specifically designed to address left ventricular remodeling. The CorCap was studied in a large, prospective, randomized, multicentered trial. This study demonstrated safety and effectiveness of the CorCap in patients with advanced heart failure and remodeled ventricles. Moreover, it provided interesting insights into mitral valve surgery in patients with heart failure. These insights and a review of the ACORN (Assessment of a Cardiac Support Device [CSD] in Patients With Heart Failure) trial are discussed in this article.

Commentary: Another epicardial device for secondary mitral regurgitation: Is this one different?

“…A measure of effectiveness of an intervention treating secondary MR is reversing the disease of the ventricle, often measured through cardiac remodeling and LV geometry. As noted by the authors, other epicardial approaches have been previously described, including suture and mesh, 7 the Acorn epicardial wrap, 8 and the LV reshaping Coapsys device (Myocor, Inc, Maple Grove, Minn) in the RESTOR-MV (Randomized Evaluation of a Surgical Treatment for Off-Pump Repair of the Mitral Valve) trial. 9 The ACORN 8 and RESTOR-MV 9 trials demonstrated improved LV geometry, but no epicardial surgical technique has been widely adopted.…”

“…As noted by the authors, other epicardial approaches have been previously described, including suture and mesh, 7 the Acorn epicardial wrap, 8 and the LV reshaping Coapsys device (Myocor, Inc, Maple Grove, Minn) in the RESTOR-MV (Randomized Evaluation of a Surgical Treatment for Off-Pump Repair of the Mitral Valve) trial. 9 The ACORN 8 and RESTOR-MV 9 trials demonstrated improved LV geometry, but no epicardial surgical technique has been widely adopted. Unlike other surgical and transcatheter devices addressing MR alone, the Mitral Touch is the latest example of an epicardial device that addresses both the secondary MR and the underlying diseased ventricle.…”

“…Previous epicardial devices [7][8][9] did not gain wide acceptance because of the invasiveness required to use them. Similarly, implantation of the Mitral Touch device is not without morbidity and still requires that surgery be performed through a sternotomy.…”

Commentary: A device for the whole mitral valve apparatus

“…In this regard, percutaneous strategies as well as epicardial approaches have been developed with the aim of reducing mortality and morbidities, with controversial results. [7][8][9][10] The major limitation of these strategies is that they do not deal with the whole MV apparatus. Specifically, percutaneous treatments do not address LV geometry restoration, whereas epicardial approaches do not focus on annular dilatation.…”