Excessive oozing through the fabric of the branched Cryolife-Jotec Evita Open NEO hybrid prosthesis

One-year outcomes of total arch replacement and frozen elephant trunk using the E-vita Open NEO

OBJECTIVES

In this cohort study, we aimed to assess the 1-year clinical outcomes of using the E-vita Open NEO™ hybrid prosthesis for total arch replacement with frozen elephant trunk (FET) to repair extensive aortic pathologies.

METHODS

We reviewed individuals who underwent thoracic aortic surgery between April 2021 and March 2023 from the Gangnam Severance Aortic Registry. Exclusion criteria included ascending aortic replacement, 1 or 2 partial arch replacement, descending aortic replacement and total arch replacement without an FET. Finally, all consecutive patients who underwent total arch replacement and FET with E-vita Open NEO for aortic arch pathologies between April 2021 and March 2023 were included in this cohort study. The patients were divided into 3 groups based on their pathology: acute aortic dissection, chronic aortic dissection and thoracic aortic aneurysm. The primary end point was in-hospital mortality. The secondary end points during the postoperative period comprised stroke, spinal cord injury and redo sternotomy for bleeding. Additionally, the secondary end points during the follow-up period included the 1-year survival rate, 1-year freedom from all aortic procedures and 1-year freedom from unplanned aortic interventions.

RESULTS

The study included 167 patients in total: 92 patients (55.1%) with acute aortic dissection, 20 patients (12.0%) with chronic aortic dissection and 55 patients (32.9%) with thoracic aortic aneurysm. The in-hospital mortality was 1.8% (n = 3). Strokes occurred in 1.8% (n = 3) of the patients, spinal cord injury in 1.8% (n = 3) and redo sternotomy for bleeding was performed in 3.0% (n = 5). There were no significant differences between the pathological groups. The median follow-up period (quartile 1-quartile 3) was 198 (37-373) days, with 1-year survival rates of 95.9%. At 1 year, the freedom from all aortic procedures and unplanned aortic interventions were 90.3% and 92.0%, respectively.

CONCLUSIONS

The 1-year clinical outcomes of total arch replacement with FET using the E-vita Open NEO were favourable. Long-term follow-up is required to evaluate the durability of the FET.

Standardized in vitro bleeding tests in a non-coated novel hybrid prosthesis for frozen elephant trunk demonstrates minimal oozing during full heparinization, supported by clinical data

Introduction

Recent reports have questioned the blood impermeability of the novel frozen elephant trunk (FET) device E-vita Open NEO© (EO-NEO). Therefore, standardized in vitro bleeding tests using porcine heparinized blood were performed, as well as stress testing on the blood tightness of the collar suture line, to investigate this observation.

Material and methods

EO-NEO prostheses were examined in vitro for blood permeability in three test series. Initially, antegrade perfusion with heparinized porcine blood [activated clotting time (ACT) of 500 s, with a 60 min duration] was performed, followed by ante/retrograde testing via the EO-NEO side port. Testing of the collar suture line under a tension of 10 Newton (N) within a suspension device (blood pressure 120 mmHg, ACT of 560 s, 1 min duration) was carried out with the suture material force fiber white (FFWs) yarn, using standard fixation (5 stitches/cm), FFWh yarn in hemostatic fixation (15 stitches/cm), and flow weave yarn (FWYh).

Results

Blood permeability testing of EO-NEO through the prosthetic lumen or via the side port demonstrated minor leakage without statistical difference between the standard and hemostatic suture lines or suture materials used, or positioning on the crimped or tapered portion (p > 0.05). The specific collar anastomosis testing demonstrated leakage volumes of 140 ml/min for FFWs vs. 16 ml/min for FFWh (p = 0.02), vs. 9 ml/min with the FWYh (p = 0.01).

Conclusion

Different blood leakage tests showed minimal oozing and no difference in blood loss through the fabric and different collar suture lines, but unphysiological pressurized retrograde perfusion of the collar region showed significantly less leakage using FWYh and FFWh, prompting production modification of EO-NEO. Clinical results confirmed low blood loss using this novel FET device.

The Frozen Elephant Technique Using a Novel Hybrid Prosthesis for Extensive Aortic Arch Disease: A Multicentre Study

INTRODUCTION

The frozen elephant trunk technique (FET) has become routine for aortic arch and descending aortic repair. New hybrid prosthesis models are constantly being developed to increase effectiveness and durability of aortic repair. Recently, concerns were raised regarding increased post-operative bleeding using a new-generation hybrid prosthesis (E-vita^® OPEN NEO, CryoLife Inc. JOTEC GmbH, Hechingen, Germany). We report the outcomes of a multi-centre experience of using the E-vita OPEN NEO.

METHODS

All patients undergoing aortic surgery at five European centres using the E-vita OPEN NEO from 2020 to 2022 were included (n = 22). The primary endpoint was the amount of chest drain fluid after 24 h and re-thoracotomy rate for bleeding.

RESULTS

Median patient age was 62.5 ± 12.6 years, 50.0% (11/22 patients) were female and 27.3% (6/22) of procedures were re-operative cardiac surgeries. Aortic dissection was present in 54.5% (12/22). The median cardiopulmonary bypass time was 148 min and ischaemia time was 84 min. Mortality at 30 days was 4.5% (1/22) and the stroke rate was 18.2% (4/22). The rate of re-thoracotomy for bleeding was 4.5% (1/22) with a median amount of chest drain fluid within 24 h of 569 (IQR 338-910) ml. There were no device-associated adverse events.

CONCLUSIONS

Use of this new-generation hybrid prosthesis for FET was safe and effective. Patient follow-up was largely uneventful given the extent of the procedures performed. In particular, bleeding events were uncommon in this cohort of patients comprising many aortic dissections and re-operative procedures. No increase in oozing was observed.

What Is the Long-Term Clinical Efficacy of the Thoraflex™ Hybrid Prosthesis for Aortic Arch Repair?

Background

The widespread adoption of the frozen elephant trunk (FET) technique for total arch reconstruction (TAR) in aortic arch aneurysm and dissection has led to the development of numerous commercial single-piece FET devices, each with its own unique design features. One such device, Thoraflex™ Hybrid (Terumo Aortic, Glasgow, Scotland), has enjoyed widespread use since its introduction. We present and appraisal of its long-term clinical efficacy, based on international data.

Materials and Methods

Pre-, intra-, and postoperative data associated with Thoraflex™ Hybrid implantations for aortic arch dissection, aneurysm, and penetrating atherosclerotic ulcer (PAU) up to April 2019 was gathered and is presented herein. Follow-up data at discharge, 3-, 6-, 12-, 24-, 36-, 48-, 60-, 72-, and 84- months post-implantation are included.

Results

Data associated with 931 cases of Thoraflex™ Hybrid implantation are included. Mean age at implantation was 63 ± 12 years. 55% of patients included were male. Aortic dissection accounted for 48% (n = 464) of cases. Mean cardiopulmonary bypass and circulatory arrest durations were 202 +72 and 69 ± 50 min, respectively. 30-day mortality was 0.6% (n = 6), while overall mortality was 14 (1.5%). Freedom from adverse events at 84 months was 95% (n = 869). Postoperative complications included neurological deficit, multi-organ failure, cardiorespiratory compromise, and infection.

Discussion

Thoraflex™ Hybrid's unique design is advantageous in comparison to market alternatives. Our data is consistent with that reported in literature and suggests Thoraflex™ Hybrid is associated with favourable rates of mortality and morbidity.

Conclusion

Thoraflex™ Hybrid remains a central player in the aortic arch prosthesis market. Its use it widespread and is associated with favourable design features and clinical outcomes relative to market alternatives.

NEO E-vita—NEO era!

In this review article, the history of the first commercially available thoracic aortic hybrid graft, the E-vita Open, later modified to the blood-impermeable E-vita Open Plus, is reported from its beginning in 2005 until its newest variation, the E-vita Open NEO, European conformity (CE) marked in 2020. Besides the background of its design and clinical experience in Essen, concomitant evolutionary steps in surgery as well as in strategic approaches like the hybrid operating room concept are displayed, finally leading to a well-rounded surgical package with a device that can be applied in all elective as well as emergency situations with complex arch involving aortic pathologies. With the E-vita Open NEO, now, surgery has been facilitated to convenient anastomosing in any of the arch zones, with the opportunity to use the island technique with a straight graft variation as well as individual head vessel anastomosing with either a trifurcated graft for zone 0 or the branched graft for zone 2 or 3 implantation. With its proven long-term stability, the surgical armamentarium to cope with complex multisegmental thoracic aortic pathologies has been significantly improved.

BioGlue and E-Vita Open NEO graft oozing: Long-term solution or band aid?

BACKGROUND

The introduction of the single-step total arch replacement (TAR) with frozen elephant trunk (FET) has revolutionised the field of aortic surgery. TAR is indicated when the aortic arch is involved in aortic pathologies such as Type A aortic dissection and thoracic aortic aneurysms. Several FET devices are available commercially for global use, and example is the E-Vita Open NEO hybrid prosthesis (HP) developed by CryoLife-JOTEC. Unlike other FET devices available, this HP in particular features a design that puts it at a disadvantage as it does not incorporate gelatine or collagen in its structure, which makes it permeable to blood. Several studies have reported incidence of post-anastomotic blood oozing through the E-Vita Open NEO right after weaning from cardiopulmonary bypass.

AIMS

This commentary aims to discuss the recent study by Tan et al. which investigated E-Vita NEO device oozing as well as the implications of using BioGlue to overcome this serious complications.

METHODS

We carried out a literature search on multiple electronic databases including PUBMED and Scopus in order to collate research evidence on E-Vita NEO device oozing, BioGlue health risks, and other commercially available and globally used FET devices such as Thoraflex Hybrid.

RESULTS

It is proven fact that the E-Vita NEO excessively oozes blood, and while BioGlue is a safe and effective agent when used in small amounts, the amount needed to coat the E-Vita Open NEO and achieve haemostasis exceeds this by a wide margin which poses patients to great potential health risks. The Thoraflex Hybrid Prosthesis developed by Terumo Aortic is a commercially available and globally used FET device with long-standing favourable outcomes.

DISCUSSION

Tan et al. recently conducted an interesting study which proved that the E-Vita NEO HP does excessively ooze blood and tackled the issue of pre-emptive BioGlue use to tackle this complication as suggested by Ho et al. This leads on to the main question, is the use of BioGlue with E-Vita Open NEO to overcome oozing a long-term sustainable solution or is it merely a band aid?

CONCLUSION

In the face of fierce commercial competition, the choice of design and material of the E-Vita Open NEO HP would benefit from reconsideration.

Prevention versus cure: Is BioGlue priming the optimal strategy against E-Vita NEO graft oozing?

BACKGROUND

Since the introduction of the E-Vita Open NEO aortic prosthesis in 2020, several incidences of post-anastomotic oozing from the polyester portion of the graft have emerged. The use of BioGlue to prime E-Vita Open NEO to prevent this has been suggested as a way to mitigate this worrying complication. We investigate the extent of graft oozing in E-Vita Open NEO and evaluate the use of BioGlue in preventing oozing, both experimentally and in terms of potential clinical complications.

MATERIALS AND METHODS

E-Vita Open NEO (in straight and branched configurations) was implanted in a perfused model. The distal stent graft and side branches were clamped, and the graft was pressurized with blood to 120 mmHg. The volume of blood (ml) oozing from the graft within 60 s was measured. Nonpressurized grafts were coated with BioGlue up to a thickness of 1, 2, and 3 mm, and the volume (mm³ ) of BioGlue required to do so was recorded.

RESULTS

Within 60 s, 250.0 ml of blood oozed from the grafts tested. 43.694, 87.389, and 174.778 mm³ of BioGlue were required to coat the device with 1, 2, and 3 mm of BioGlue.

CONCLUSION

Graft oozing from E-Vita Open NEO represents an omnipresent and worrying risk. The use of BioGlue herein is likely associated with several adverse consequences, which are an additional risk on top of that posed by graft oozing. These risks call into question the suitability of E-Vita Open NEO, especially when compared to alternative devices not affected by oozing.

Correlation of coagulopathy and frozen elephant trunk use in aortic arch surgery: A systematic review and meta-analysis

BACKGROUND

The advent of frozen elephant trunk (FET) for reconstruction of elective and nonelective aortic arch surgery has augmented the treatment of complex aortic pathologies in a single-stage operation. To date, no studies have been focused on the prevalence and predictors of coagulopathy potentiated by FET procedure.

METHODS

In a systematic review, we searched databases up to June 2020 to find studies reporting coagulopathy complications after FET procedure. A proportional meta-analysis was carried out using STATA software (StataCorp).

RESULTS

A total of 46 studies consisting of 6313 patients were eligible. The pooled estimation of reoperation for postoperative bleeding was 7% (95% confidence interval [CI:] 5-8; I²  = 84.73%; reported by 39 studies including 4796 patients). The mean volume of transfused packed blood cells and fresh frozen plasma was 1677 ml (95% CI: 1066.4-2287.6) and 1016.5 ml (95% CI: 450.7-1582.3). The subgroup by the stent type showed a decrease in the heterogeneity (I²  = 0.01%, I²  = 53.95%, I²  = 0.01%, and I²  = 54.41% for Thoraflex® Hybrid, E-vita®, Frozenix®, and Cronus®, respectively). The subgroup by the chronicity of operation resulted in less heterogeneity among patients undergoing elective compared with nonelective operation (I²  = 29.22% vs. I²  = 80.56% in nonelective). Meta-regression analysis showed that age and male gender significantly impacted on the reoperation for postoperative bleeding.

CONCLUSIONS

The FET procedure for arch replacement is associated with coagulopathy complications and the transfusion of blood products. Male, age, and selective choice of FET use were found to be the heterogeneity sources of reoperation for postoperative bleeding.

Pre-emptive BioGlue priming of the branched Evita Open NEO hybrid prosthesis: tackling excessive oozing

Excessive oozing after total arch replacement with the frozen elephant trunk technique through the fabric of the E-vita Open NEO raised concern about its early adaptation. The mechanism is speculated to be multifactorial. Our goal was to report our approach using pre-emptive BioGlue priming on the fabric against the oozing phenomenon.