title: Transcatheter valve-in-valve implantation versus reoperative conventional aortic valve replacement: a systematic review.
abstract: Transcatheter valve-in-valve (VIV) implantation for degenerated aortic bioprostheses has emerged as a promising alternative to redo conventional aortic valve replacement (cAVR). However there are concerns surrounding the efficacy and safety of VIV. This systematic review aims to compare the outcomes and safety of transcatheter VIV implantation with redoes cAVR. Six databases were systematically searched. A total of 18 relevant studies (823 patients) were included. Pooled analysis demonstrated VIV achieved significant improvements in mean gradient (38 mmHg preoperatively to 15.2 mmHg postoperatively, P<0.001) and peak gradient (59.2 to 23.2 mmHg, P=0.0003). These improvements were similar to the outcomes achieved by cAVR. The incidence of moderate paravalvular leaks (PVL) were significantly higher for VIV compared to cAVR (3.3% vs. 0.4%, P=0.022). In terms of morbidity, VIV had a significantly lower incidence of stroke and bleeding compared to redo cAVR (1.9% vs. 8.8%, P=0.002 & 6.9% vs. 9.1%, P=0.014, respectively). Perioperative mortality rates were similar for VIV (7.9%) and redo cAVR (6.1%, P=0.35). In conclusion, transcatheter VIV implantation achieves similar haemodynamic outcomes, with lower risk of strokes and bleeding but higher PVL rates compared to redo cAVR. Future randomized studies and prospective registries are essential to compare the effectiveness of transcatheter VIV with cAVR, and clarify the rates of PVLs.
authors.affiliation: 1 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia ; 2 Cardiac Surgery Unit Cardiovascular Department 'G. Mazzini' Hospital Piazza Italia, 64100 Teramo, Italy.
authors.forename: Kevin
authors.initials: K
authors.lastname: Phan
authors.affiliation: 1 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia ; 2 Cardiac Surgery Unit Cardiovascular Department 'G. Mazzini' Hospital Piazza Italia, 64100 Teramo, Italy.
authors.forename: Dong-Fang
authors.initials: DF
authors.lastname: Zhao
authors.affiliation: 1 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia ; 2 Cardiac Surgery Unit Cardiovascular Department 'G. Mazzini' Hospital Piazza Italia, 64100 Teramo, Italy.
authors.forename: Nelson
authors.initials: N
authors.lastname: Wang
authors.affiliation: 1 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia ; 2 Cardiac Surgery Unit Cardiovascular Department 'G. Mazzini' Hospital Piazza Italia, 64100 Teramo, Italy.
authors.forename: Ya Ruth
authors.initials: YR
authors.lastname: Huo
authors.affiliation: 1 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia ; 2 Cardiac Surgery Unit Cardiovascular Department 'G. Mazzini' Hospital Piazza Italia, 64100 Teramo, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Di Eusanio
authors.affiliation: 1 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia ; 2 Cardiac Surgery Unit Cardiovascular Department 'G. Mazzini' Hospital Piazza Italia, 64100 Teramo, Italy.
authors.forename: Tristan D
authors.initials: TD
authors.lastname: Yan
keywords: Transcatheter; aortic valve replacement; outcomes; reoperative; valve-in-valve