Comparison of Two Generations of Self-Expandable Transcatheter Heart Valves in Nine Surgical Valves: An In Vitro Study.

(1) Background: This study aimed to analyse the hydrodynamic performance of two generations of self-expanding transcatheter heart valves (THV) as a valve-in-valve (ViV) in different surgical aortic valve (SAV) models under standardised conditions. The nitinol-based Evolut R valve is frequently used in ViV procedures. It is unclear whether its successor, the Evolut PRO, is superior in ViV procedures, particularly considering the previously implanted SAV model.

Characteristic calcification behavior of five surgical aortic valve bioprostheses models: An in vitro study.

Background And Aims: The durability of surgical aortic valve bioprostheses (SAV) is limited by the calcification of the leaflets, which results in degeneration. In clinical routine, there seems to be substantial variability in the degeneration of specific SAV models. Our study aims to establish an in vitro calcification model for prosthetic valves, characterizing the calcification behavior of different SAVs.

Impact of Different Valve-in-Valve Positions on Functional Results of the New Generation of Balloon-Expandable Transcatheter Heart Valve.

Objectives:  Very precise positioning of the transcatheter heart valve (THV) inside the degenerated SAV is a crucial factor for valve-in-valve (ViV) procedure to achieve optimal hemodynamic results. Therefore, our study aimed to investigate the impact of implantation depth on functional results after ViV procedures in a standardized in vitro setting.

Methods:  THV (SAPIEN 3 Ultra 23-mm size) and three SAV models (Magna Ease, Trifecta, and Hancock II-all 21-mm size) were tested at different circulatory conditions in five different positions of the THV (2-6 mm) inside the SAV.

[Challenges and options for advanced training in surgery : An interdisciplinary position paper against the background of the hospital structural reform in Germany].

Background: Even now the further training in surgery faces considerable challenges. The planned hospital structural reform will result in new bureaucratic and organizational hurdles, which could lead to a considerable loss of quality in advanced surgical training across all disciplines.

Objective: The aim of this position paper is to describe the current and future challenges for advanced surgical training and to identify possible approaches and opportunities for the further development against the background of the planned hospital structural reform.

Ex vivo evaluation of 3 different right ventricular outflow tract substitutes.

Objectives: The Ross procedure represents an excellent treatment option in younger patients with aortic stenosis but is limited by poor availability of homografts. In this study, we investigated the hydrodynamic performance of 3 different types of right ventricular outflow tract replacement with pericardium or synthetic material.

Methods: Three different types of valved conduits were constructed using pericardium and/or synthetic material (Group PEPE: pericardial cusps and pericardial conduit, Group PEPR: pericardial cusps and Dacron conduit, Group PRPR: expanded polytetrafluoroethylene cusps and Dacron conduit).

Impact of different in vitro models on functional performance of the self-expanding transcatheter heart valve.

Objectives: Transcatheter heart valves (THVs) are investigated according to International Organization for Standardization requirements using in vitro heart simulators to evaluate hydrodynamic performance. In contrast to surgical valves, a THV's performance heavily depends on the configuration and shape of the aortic anulus. In International Organization for Standardization regulations, there is no detailed definition for the construction of a compartment in which a THV has to be tested.

Impact of high-pressure balloon aortic valvuloplasty on the hydrodynamic result after a transcatheter valve-in-valve procedure.

Objectives: The aim of this study was to investigate the degree of functional improvement of a transcatheter heart valve (THV) for valve-in-valve after bioprosthetic valve fracture (BVF) of three small surgical aortic valve bioprostheses (SAVBP) using high-pressure balloon aortic valvuloplasty (HP-BAV) under standardized ex-vivo-conditions.

Methods: A THV 26 mm (Evolut R) and SAVBP 21 mm (Perimount Magna Ease, Trifecta, and Epic supra [n = 4] were used. Mean pressure gradient (MPG), effective orifice area (EOA), geometric orifice area (GOA), minimal internal diameter (MID), and pinwheeling index (PWI) were analyzed before and after HP-BAV of the SAVBP using a noncompliant balloon.

Functional performance of 8 small surgical aortic valve bioprostheses: an in vitro study.

Objectives: Selection of a surgical aortic valve (SAV) bioprosthesis model for the treatment of aortic valve disease remains controversial. The aim of this study was to characterize the functional performance of 8 SAV models in a standardized in vitro setting.

Methods: The hydrodynamic performance of 8 SAVs with labelled size 21 mm (Avalus™, Hancock® II, Mosaic® Ultra™, Perimount®, Perimount® Magna Ease, Epic™ Supra, Trifecta™ GT; Freestyle®), was investigated in a pulse duplicator.

Ex vivo evaluation of the Ozaki procedure in comparison with the native aortic valve and prosthetic valves.

Objectives: We investigated the hydrodynamic performance and cusp kinematics of the Ozaki neocuspidized aortic valve in comparison with the native aortic and prosthetic valves in an ex vivo study.

Methods: Native aortic valves of swine hearts were replaced by aortic valve substitutes, and their hydrodynamic performance (effective orifice area and mean pressure gradient) was evaluated in a mock circulation under defined conditions. The following aortic valve substitutes were investigated: native aortic valve, Ozaki valve, Perimount Magna Ease, Trifecta and St.

The figure-of-8 aortic valve suturing technique optimizes the effective orifice area of a small aortic annulus-an ex vivo study.

Objectives: Surgical aortic valve replacement (SAVR) in small annuli carries an elevated risk for the patient-prosthesis mismatch. In this study, we systematically investigated the influence of different implantation techniques including annular enlargement (AE) on the functional result after SAVR in small annuli using a standardized ex vivo model.

Methods: SAVR using the PERIMOUNT Magna Ease® (PME) 21 mm was performed in small porcine aortic roots using 4 implantation techniques: non-everting pledgeted (NE) suture, single interrupted (SI) suture, continuous suture (CS), figure-of-8 (F8) suture, as well as the PME 23 mm after AE using the Nunez method and the NE suture technique (PME23 AE).

Impact of different valve-in-valve positions on the hydrodynamic performance of the newest-generation self-expanding transcatheter heart valve.

Objectives: Transcatheter aortic valve-in-valve (ViV) procedures are increasingly performed for the treatment of degenerated surgical aortic valves with a high risk for a redo operation. For an optimal functional result, precise positioning of the transcatheter heart valve (THV) inside the SHV is crucial. The aim of this study was to systematically investigate the impact of implantation depth on the functional result after a ViV procedure in a standardized in vitro setting.

Impact of tricuspid valve insufficiency on the performance of left ventricular assist devices.

Objective: To evaluate the impact of severe tricuspid valve insufficiency (TVI) at the time of left ventricular assist device (LVAD) implantation on the hemodynamic and LVAD parameters in an acute ovine model.

Methods: Stable heart failure (HF) was induced in 10 ovines through the application of 3 ± 1 coronary ligations. Once stable HF was obtained (after 15 ± 5 days), the animals were supported with an LVAD.

Chronic stable heart failure model in ovine species.

Establishing a chronic heart failure (HF) model is challenging, particularly in the ovine model. The aim of this study was to establish a reproducible model of HF in an ovine model. Seventeen sheep were operated using the left thoracotomy approach.

Gastrointestinal Bleeding in Patients with HeartWare Ventricular Assist Device: Does the Activation of the Lavare Cycle Make a Difference?

We aimed to investigate the prevalence of gastrointestinal bleeding (GIB) events in patients supported with HeartWare ventricular assist device (VAD) and activated lavare cycle. Thirty-two GIB events were documented in 22 patients (21%) after median support duration of 22 days (IQR: 11-157 days). There were 13 patients with early episodes of GIB.

Implanting permanent left ventricular assist devices in patients on veno-arterial extracorporeal membrane oxygenation support.

Selected patients who fail to be weaned off temporary veno-arterial extracorporeal membrane oxygenation support may be considered for long-term left ventricular assist devices.  We describe here a left ventricular assist device implantation technique in patients with prior veno-arterial extracorporeal membrane oxygenation support without the use of a cardiopulmonary bypass machine, which minimizes the intraoperative trauma and blood loss while still meeting all the goals of the standard procedure.

Prevalence of De Novo Aortic Valve Insufficiency in Patients After HeartWare VAD Implantation with an Intermittent Low-Speed Algorithm.

De novo aortic valve insufficiency (AI) is a frequent occurrence in patients supported with left ventricular assist device (LVAD). The European version of the HeartWare LVAD has intermittent low-speed software (lavare cycle) to facilitate intermittent aortic valve opening. We examined aortic valve opening status and prevalence of AI in patients supported with HeartWare LVAD and activated lavare cycle.