Mitral Valve Replacement Adopting Chimney Technique in Mitral Insufficiency And Extensive Mitral Annular Calcification: A Case Report

Abstract

Extensive and serious mitral annular calcification represents a troublesome obstacle in intracardiac mitral valve replacement due to time-consuming requirements and the potential of decalcification-associated complications. We report the case of a high-risk patient with extremely severe mitral insufficiency and difficult-to-debride annular calcification who received mitral replacement using a chimney technique. This approach enabled not only the minimization of mitral calcification debridement but also the reduction of surgery time. Consequently, the surgery was successful with a great postoperative outcome. Thus, this technique is a safe and feasible option to deal with intractable mitral annular calcification during mitral valve surgery.

Early and Mid-Term Outcomes of Using the Chimney Technique in Redo Mitral Valve Replacement in Patients with a Small Mitral Annulus

“…This technique enables the surgeon to install a larger valve, circumventing the necessity for re-replacement, a frequent occurrence in pediatric populations due to the growth of children [ 11 ]. Subsequently, this technique was reported to be used for PPM issues in the adult aortic valve position [ 12 ] as well as for severe MAC in MVR [ 13 , 14 ]. Moreover, considering that redo surgery requires extensive debridement of the mitral annulus, it may lead to two potential outcomes: firstly, excessive removal of the native valve annulus during debridement may render it impossible to suture the new prosthetic valve; secondly, the trauma from the initial surgery may result in impaired healing and scar formation in cardiac tissues, causing further narrowing of the mitral annulus, making it unsuitable for implanting an ideal size valve.…”

“…The chimney technique was initially employed to address PPM in pediatric patients undergoing MVR [ 11 ]. The technique was subsequently reported to be used to solve PPM in adults undergoing the Bentall procedure [ 12 ] and to avoid complete mitral annular calcification (MAC) debridement in adults with severe mitral stenosis and massive MAC [ 13 , 14 ]. The main challenges in small mitral valve Re-MVR are the difficulty of intraoperative removal of diseased tissue from the annulus and postoperative PPM resulting from non-ideal valve size implantation.…”

Early and Mid-Term Outcomes of Using the Chimney Technology in Redo-Mitral Valve Replacement in Patients with Small Mitral Annulus

“…To our knowledge, this is the largest series of redo-mitral valve replacement with the use of the chimney technology for a small mitral valve annulus (<25 mm). The chimney technology is currently described in case reports for the resolution of PPM in pediatric patients undergoing MVR [11] and adult patients undergoing the Bentall procedure [12] and for the resolution of MVR in severe MAC patients [13,14]. The small mitral annulus may be the result of extensive calcification of the mitral annulus to the leaflets, small patient size, or previous mitral repair with a small annular ring5.…”

“…The chimney technology was first reported to be used to solve patient-prosthesis mismatch (PPM) in pediatrics undergoing MVR [11]. The technique was subsequently reported to be used to solve PPM in adults undergoing Bentall procedure [12] and to avoid complete mitral annular calcification (MAC) debridement in adults with severe mitral stenosis and massive MAC [13,14]. The main challenges in small mitral valve redo-MVR are the difficulty of intraoperative removal of diseased tissue from the annulus and postoperative PPM, and there is no feasible treatment option that can effectively address these challenges.…”