Ross Operation in Neonates: A Meta-analysis.

BACKGROUND: The Ross operation is the preferred treatment for aortic valve replacement in children. However previous studies indicate that outcomes in neonates are poor. This meta-analysis examines the pooled outcomes of the Ross operation in neonates. METHODS: Four major databases (PubMed/MEDLINE, EMBASE, Scopus, and ScienceDirect) were searched from inception until May 1, 2020 for studies describing outcomes of the Ross operation in neonates. The primary outcome was early mortality, and secondary outcomes were late mortality and mechanical support. Random-effects models were used to account for possible heterogeneity between studies, and continuity corrections were used to include zero total event trials. RESULTS: Eighteen studies comprising outcomes data on 181 neonates were included in the analysis. Meta-analysis showed a pooled early mortality rate of 24% (95% confidence interval, 12%-38%; I2 = 52%, P for heterogeneity = .01). Meta-regression analysis showed that more recently published studies reported significantly worse early mortality (P = .03). The pooled incidence of postoperative mechanical support was 15% (95% confidence interval, 5%-28%; I2 = 28%, P for heterogeneity = .22). No evidence of publication bias was found according to Egger's test (bias coefficient = 0.21, P = .57). CONCLUSIONS: The neonatal Ross operation carries a high early mortality rate. The treatment of unrepairable aortic valves in neonates remains an unsolved problem in congenital cardiac surgery.

Smart materials in cardiovascular implants: Shape memory alloys and shape memory polymers.

Smart materials have intrinsic properties that change in a controlled fashion in response to external stimuli. Currently, the only smart materials with a significant clinical impact in cardiovascular implant design are shape memory alloys, particularly Nitinol. Recent prodigious progress in material science has resulted in the development of sophisticated shape memory polymers. In this article, we have reviewed the literature and outline the characteristics, advantages, and disadvantages of shape memory alloys and shape memory polymers which are relevant to clinical cardiovascular applications, and describe the potential of these smart materials for applications in coronary stents and transcatheter valves.