Introduction
The clinical implementation of transcatheter aortic valve replacement (TAVR) induced profound and ongoing changes in treatment of valvular heart disease [1-3]. Since the first successful TAVR, as reported by Alain Cribier in 2002, TAVR has advanced to an essential part in contemporary heart valve therapy [4].
At the same time, surgical aortic valve replacement (AVR) experienced significant changes too [2]. Today, bioprosthetic valves are preferred over mechanical valves by physicians and patients. Recently, more than 80% of all surgically implanted valves are biologic substitutes [2, 5-7]. Even industry adopted this trend and brought “valve-in-valve-TAVR-ready”-implants into the market [8]. Despite reported long-term results for more than 20 years, the basically limited durability of bioprosthetic valves still is an important issue [9].
For those reasons, a significant number of patients presenting with a failed aortic bioprosthesis will be upcoming in the near future. Most of those patients are suitable for conventional redo-surgery at nearly normal risk. But for some higher risk subgroups, undoubted a significantly increased risk for mortality or morbidity up to 20% is reported [2, 5, 10, 11].
An alternative to surgical redo AVR, is “valve-in-valve” TAVR (VIV-TAVR) for failed aortic bioprostheses, as firstly described by Walther et al. in 2007 [2, 3, 12]. Since then, VIV-TAVR continuously spread into the TAVR-centers and today is an established treatment option.
Already in 2014 Dvir et al. reported the initial outcomes of VIV-TAVR in the largest multicenter valve-in-valve registry, including 459 patients and 55 centers worldwide [13]. In this work, Dvir demonstrated the feasibility and safety of the VIV-procedure in a large multicentric cohort [13]. The initial results confirmed good immediate and one-year outcomes [13]. But already this early study described inferior results for patients with small prosthesis and predominant valve stenosis [13].
Up today, there exists only little information concerning mid-term, and no information about long-term durability of VIV-TAVR. The presently available studies contain only limited data, mostly reporting a follow-up limited to one year ([13-16]. Recently, a sub-analysis of the PARTNER 2-registry reported 3-year outcomes, but under exclusion of bioprosthetic valves with a labeled diameter less than 21mm [17]. The longest follow-up is provided by Bleiziffer et al., reporting 5-years clinical data of the VIVI-registry, but lacking echocardiographic data [18].
To address this lack of knowledge in present literature, this study adds a 3-years echocardiographic follow-up after VIV-TAVR.