The Fate of Conventional Elephant Trunk in the Frozen Elephant Trunk Era

Conventional elephant trunk (cET) and frozen elephant trunk (FET) are two distinct approaches to the surgical treatment of thoracic aortic aneurysms and dissections. With the advent and growing uptake of endovascular technologies, FET is becoming increasingly popular for its potential to be performed as a single-stage operation with better aortic remodeling and less risk of graft kinking than the traditional two-stage cET procedure. However, FET has been associated with a higher risk of spinal cord ischemia and its use in patients with connective tissue disorder remains controversial. The current review aimed to reflect on recent evidence surrounding the application of cET and FET to different types of aortic pathology in both acute and elective settings. Another scope of this review was to compare the characteristics of the currently available FET commercial devices on the global market. Our findings highlight that when the pathology is confined to the proximal descending aorta, such as in Dsine, intervention is often single-staged and false lumen (FL) thrombosis is achieved with good effect. FET remains limited by spinal cord injury and applicability in patients with connective tissue disorder, although some groups have started to circumvent associated complications, likely due to growing surgical expertise. Many other aortic diseases do require second-stage intervention, and even in these cases, there appears to be lower in-hospital mortality when using FET over cET. This is possibly due to the higher rate of endovascular completion facilitated by the completed landing zones created during FET. FET is trending toward becoming the universal treatment modality for extending repair to the descending aorta.

Early and midterm results of frozen elephant trunk operation with Evita open stent-graft in patients with Marfan syndrome: results of a multicentre study

Background

Endovascular treatment of patients with Marfan syndrome (MFS) is not recommended. Hybrid procedures such as frozen elephant trunk (FET), which combines stent-graft deployment with an integrated non-stented fabric graft for proximal grafting and suturing, have not been previously evaluated. The aim of this study was to assess the safety and feasibility of FET operation in patients with MFS.

Methods

Patients enrolled in the International E-vita Open Registry (IEOR) who underwent FET procedure between January 2001 and February 2020 meeting Ghent criteria for MFS were included in the study. Early and midterm results were retrospectively analyzed. Preoperative, postoperative and follow-up computed tomography angiography scans were analysed.

Results

We analyzed 37 patients [mean age 38 ± 11 years, 65% men]. Acute or chronic aortic dissection was present in 35 (95%) patients (14 and 21 patients respectively). Two (5%) patients had an aneurysm without dissection. Malperfusion syndrome was present in 4 patients. Twenty-nine (78%) patients had history of aortic surgical interventions. The 30-day and in-hospital mortality amounted to 8 and 14% respectively. False lumen exclusion was present in 73% in stented segment in last postoperative CT. The overall 5-year survival was 71% and freedom from reintervention downstream was 58% at 5 years. Of the nine patients who required reintervention for distal aortic disease, one patient died.

Conclusions

FET operation for patients with MFS can be performed with acceptable mortality and morbidity. In long-term follow-up no reinterventions on the aortic arch were required. FET allows for easier second stage operations providing platform for surgical and endovascular reinterventions.

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.

A New Era of Diagnosis and Therapy in Acute Aortic Syndromes: The Mainz-Essen Experience (Part II)-Management and Outcomes

Over the years, the cardiovascular department of Johannes Gutenberg University in Mainz-West-German Heart Centre in Essen (Germany) designed and implemented the hybrid operating room (2003) along with advanced endovascular and surgical procedures, including the frozen elephant trunk technique. For the study purpose, the Mainz-Essen experience on acute aortic syndromes was summarized by considering original articles from single-center or multicenter studies performed at West German Heart Centre, Essen, Germany, or at the cardiovascular department of Johannes Gutenberg University, Mainz, Germany. We present the 35-year-long Mainz-Essen research, education, and patient management journey in creating an integrated multidisciplinary "Aortic Center" in the heart of Europe.

Total aortic arch replacement using the thoraflex hybrid prosthesis: early- and medium-term results from a Scandinavian center

OBJECTIVE

The purpose of this study was to assess our early experience with the Thoraflex hybrid prosthesis. Design. This was a retrospective, single-center cohort study.

RESULTS

Between December 2014 and December 2019, 34 patients underwent total aortic arch replacement with the Thoraflex hybrid prosthesis. Fifteen of the patients had pre-operative chronic aortic dissection. The mean cardiopulmonary bypass time was 200 ± 35 min, aortic cross clamp time 114 ± 34 min, deep circulatory arrest time to the lower body 60 ± 22 min, and selective antegrade cerebral perfusion time 67 ± 24 min. The rate of stroke was 11.7% (4/34), paraparesis was 8.8% (3/34) and renal failure was 11.7% (4/34). No patient required permanent dialysis. Three (8.8%) patients died within the first 30 days postoperatively. All early deaths were due to stroke or spinal cord complications. During follow-up, an additional four patients died. Average follow-up was 32.4 ± 19.4 months (1102 patient-months) and was 100% complete. Survival at 12 months and 36 months was 88% ± 7.2% and 75% ± 12.7%, respectively.

CONCLUSIONS

The Thoraflex hybrid prosthesis can be used in the setting of total aortic arch replacement with good early- and medium-term results. Stroke and spinal cord complications remain an important source of early mortality.

Outcomes of long versus short stent cronus hybrid prosthesis in type A aortic dissection: A single centre experience

OBJECTIVES

The frozen elephant trunk (FET) technique has become an important tool in the treatment of acute type A aortic dissection. The aim of this study was to evaluate the effect of long FET on spinal cord injury (SCI) and distal aortic remodeling after acute type A aortic dissection based on clinical and radiological outcomes.

METHODS

From January 2018 to November 2019, 158 patients (mean age 51.8 years [range: 32-78 years], 88.6% male) with acute type A aortic dissection were treated by FET with 100 mm (n = 113) or 150 mm (n = 45) open hybrid stent graft prosthesis. Patients were divided into two groups according to the length of FET. The clinical and radiological outcomes of the patients were reviewed retrospectively.

RESULTS

Postoperative outcomes did not differ significantly: in-hospital mortality (9.7% vs. 6.7%, p = .758) and SCI (5.3% vs. 2.2%, p = .674). Aortic remodeling, which was evaluated by aortic diameter, true lumen diameter, false lumen (FL) diameter and the rate of FL complete thrombosis, was more positive in long FET group in the descending thoracic aorta during the follow-up period. At the abdominal level, there was no statistically significant difference between the two groups.

CONCLUSIONS

The long version of FET does not increase the risk of SCI in patients with acute type A aortic dissection. The application of long FET can achieve better results in terms of remodeling of the thoracic aorta in the short- and medium-term follow-up.

Hybrid repair versus conventional open repair for thoracic aortic arch aneurysms

BACKGROUND

Thoracic aortic arch aneurysms (TAAs) can be a life-threatening condition due to the potential risk of rupture. Treatment is recommended when the risk of rupture is greater than the risk of surgical complications. Depending on the cause, size and growth rate of the TAA, treatment may vary from close observation to emergency surgery. Aneurysms of the thoracic aorta can be managed by a number of surgical techniques. Open surgical repair (OSR) of aneurysms involves either partial or total replacement of the aorta, which is dependent on the extent of the diseased segment of the aorta. During OSR, the aneurysm is replaced with a synthetic graft. Hybrid repair (HR) involves a combination of open surgery with endovascular aortic stent graft placement. Hybrid repair requires varying degrees of invasiveness, depending on the number of supra-aortic branches that require debranching. The hybrid technique that combines supra-aortic vascular debranching with stent grafting of the aortic arch has been introduced as a therapeutic alternative. However, the short- and long-term outcomes of HR remain unclear, due to technical difficulties and complications as a result of the angulation of the aortic arch as well as handling of the arch during surgery.

OBJECTIVES

To assess the effectiveness and safety of HR versus conventional OSR for the treatment of TAAs.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 22 March 2021. We also searched references of relevant articles retrieved from the electronic search for additional citations.

SELECTION CRITERIA

We considered for inclusion in the review all published and unpublished randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing HR to OSR for TAAs.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all titles and abstracts obtained from the literature search to identify those that met the inclusion criteria. We retrieved the full text of studies deemed as potentially relevant by at least one review author. The same review authors screened the full-text articles independently for inclusion or exclusion.

MAIN RESULTS

No RCTs or CCTs met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

Due to the lack of RCTs or CCTs, we were unable to determine the safety and effectiveness of HR compared to OSR in people with TAAs, and we are unable to provide high-certainty evidence on the optimal surgical intervention for this cohort of patients. High-quality RCTs or CCTs are necessary, addressing the objective of this review.

"Proximalization is Advancement"-Zone 3 Frozen Elephant Trunk vs Zone 2 Frozen Elephant Trunk: A Literature Review

Over the decades, the Frozen Elephant Trunk (FET) technique has gained immense popularity allowing simplified treatment of complex aortic pathologies. FET is frequently used to treat aortic conditions involving the distal aortic arch and the proximal descending aorta in a single stage. Surgical preference has recently changed from FET procedures being performed at Zone 3 to Zone 2. There are several advantages of Zone 2 FET over Zone 3 FET including reduction in spinal cord injury, visceral ischemia, neurological and cardiovascular sequelae. In addition, Zone 2 FET is a technically less complicated procedure. Literature on the comparison between Zone 3 and Zone 2 FET is scarce and primarily observational and anecdotal. Therefore, further research is warranted in this paradigm to substantiate current surgical treatment options for complex aortic pathologies. In this review, we explore literature surrounding FET and the reasons for the shift in surgical preference from Zone 3 to Zone 2.

The frozen elephant trunk technique for acute retrograde type A aortic dissection: preliminary results

OBJECTIVES

Our goal was to determine the early and midterm outcomes after total arch replacement with the frozen elephant trunk (FET) technique compared to those of the conventional elephant trunk (ET) technique for acute retrograde type A aortic dissection.

METHODS

Between 2012 and 2019, a total of 49 patients had total arch replacement for acute retrograde type A aortic dissection. Patients were divided into the conventional ET (n = 17) and FET (n = 32) groups. The false lumen status was evaluated using enhanced computed tomography (CT) 1 week postoperatively. The diameter of the downstream aorta was evaluated annually using CT. The median follow-up period was 29 months.

RESULTS

Preoperative data and neurological complications were not significantly different in the 2 groups. The diameter and length of the ET prosthesis were significantly larger and longer in the FET group. The overall early mortality rate was 10.2% (5/49) with no differences between the 2 groups. The mean follow-up period was significantly longer in the conventional ET group. The rates of freedom from aortic events at 3 years were significantly lower in the FET group. At the level of the distal arch, postoperative false lumen patency was significantly lower and the follow-up aortic diameter was significantly smaller in the FET group.

CONCLUSIONS

The FET technique facilitates false lumen thrombosis and aortic remodelling at the distal arch level, with fewer adverse aortic events during the follow-up period with acceptable early outcomes; however, these findings are exploratory and require investigation.

Comparison between Arch Zones in Modified Frozen Elephant Trunk Procedure for Complex Thoracic Aortic Diseases

Introduction

The aim of this study is to compare postoperative outcomes and follow-up of two different modifications facilitating surgical technique of frozen elephant trunk (FET) procedure for complex thoracic aortic diseases - zone 0 (fixation with total arch debranching) and zone 3 (fixation with islet-shape arch repair).

Methods

From May 2012 to December 2018, data were collected from 139 patients who had been treated with FET procedure for complex thoracic aortic diseases. According to Ishimaru arch map, patients with proximal anastomotic site of hybrid graft at zone 0 and zone 3 were grouped as Group A (n=58, 41.7%) and Group B (n=81, 58.3%), respectively. Mean age of study population was 54.7±11.4 years, and 111 patients were male (79.9%).

Results

In-hospital mortality was observed in 20 (14.4%) patients (n=12, acute type A aortic dissection, and n=4, previous aortic dissection surgery). There was no significant difference between both groups in terms of in-hospital mortality. Four patients from Group A and three patients from Group B had permanent neurological deficit (P=0.32). Three patients from both groups had transient spinal cord ischemia (P=0.334). Although mean total perfusion time was longer in Group A, duration of visceral ischemia, when compared with Group B, was shorter (P<0.001). Five-year survival rate was 82.8% in Group A and 81.5% in Group B (P=0.876).

Conclusion

FET procedure is a feasible repair technique in the treatment of complex aortic diseases, providing satisfactory early results. Because of its advantageous aspects, zone 0 fixation with debranching is the preferred technique in our clinic.

Frozen elephant trunk with straight vascular prosthesis

We present a recapitulation of 15 years of experience starting with conception, inception, development, and clinical implementation and application of the E-vita open hybrid graft. Concomitantly, we delve into surgical techniques that shaped our clinical results. Introduced in February 2005, the novel "Essen I Prosthesis", was first-in-human surgically implanted. Follow on to this success, and within six months, eight further applications were performed. Once, the CE mark was attained, the prosthesis was branded as E-vita Open Prosthesis. In 2008, the blood-tight modification was introduced, and with time and clinical practice and application, the device's indications were expanded. Hence, the focus remained on managing complex thoracic aneurysmal disease and in particular acute and chronic type I aortic dissections. With the surge of our surgical experience and the integration of various surgical modifications, 30-days mortality was reduced to 12%, while morbidities such as stroke and spinal cord injury were reduced to 7% and 3%, respectively. The rate of re-intervention on distal aorta was significantly reduced; an attestation to the prosthesis's effectuated performance which contrasted proximal aortic repairs. With new additional device variations on the horizon, a wider range of patient-specific treatment options can now be offered.

Postoperative care in patients with DeBakey type I aortic dissection: criteria of aortic remodeling and risk factors of disease progression

AIM

To present current treatment modes for DeBakey type I aortic dissection, to compare their early and mid-term postoperative results, to evaluate predictors of negative aortic remodeling after surgery.

MATERIAL AND METHODS

Retrospective cohort analysis included 78 patients with DeBakey type I aortic dissection who underwent surgical treatment in 2009-2017. Patients were divided into 3 groups depending on type of intervention: group I (n=22) - Elephant Trunk procedure, group II (n=29) - hybrid interventions, group III (n=27) - proximal aortic replacement alone. Early postoperative results and aortic remodeling in mid-term postoperative period were compared.

RESULTS

There were no significant differences in postoperative morbidity, in-hospital mortality and freedom from aortic death. However, 7 patients were lost for follow-up in group III. Analysis of false lumen patency showed results in favor of more aggressive approach (groups I and II) with significantly higher rate of false lumen thrombosis in segments 1 and 2 (p<0,001 and p=0,004 respectively). Freedom from negative aortic remodeling was also significantly higher in groups I and II. Risk factors of patent false lumen were residual fenestration, large volume of false lumen in segment 2, dissection of supra-aortic vessels and connective tissue disorders. Risk factors of negative aortic remodeling were connective tissue disorders, patent false lumen and dissection of supra-aortic vessels.

CONCLUSION

Advanced surgical approach (Elephant Trunk procedure or hybrid interventions) should be preferred for DeBakey type I aortic dissection.

[Aortic diseases : Modern diagnostic and therapeutic strategies]

Aortic diseases include not only the thoracic but also the abdominal part of the aorta. In the etiology cardiovascular risk factors, such as hypertension, smoking and hyperlipoproteinemia play a major role, but more and more genetic diseases with familiar predisposition are being identified. Even large aneurysms remain asymptomatic as long as other organs in the neighborhood are not damaged and no acute aortic event occurs including aortic dissection, intramural hematoma, penetrating aortic ulcer, and traumatic aortic injury. Standardized algorithms allow precise and rapid diagnosis for initiating medicinal therapy or operative and/or endovascular interventions (thoracic/endovascular aortic repair, TEVAR/EVAR) in this emergency situation. Specialized aortic centers are recommended to form localized regional networks.

Conservative management versus endovascular or open surgery in the spectrum of type B aortic dissection

Background

Type B aortic dissection is a life-threatening acute aortic condition often with acute ischemic signs or symptoms. With initial management focusing on alleviating malperfusion and pain, and avoiding propagation of dissection or rupture both systolic blood and pulse pressure should be reduced initially by an aggressive medical approach. In the setting of persistent signs of complications endovascular strategies have replaced open surgery and led to a fourfold increase in early survival and better long-term outcomes.

Methods

An electronic health database search was performed on articles published between January 2006 and July 2017. Publications were included in this review if (I) the index aortic pathology was type B aortic (distal) dissection; (II) when medical management, open surgical replacement or thoracic endovascular aortic repair were among those options; (III) when at least one of all basic outcome criteria such as survival, spinal cord ischemia and cerebrovascular accident was reported; (IV) when ≥15 serial patients were included. A total of 62 studies were eligible and analysed.

Results

Our manuscript has summarized data collected over 12 years on management specific outcomes in the setting of distal aortic dissection and provides an up-to-date interpretation of the published evidence. For complicated cases, treated acutely, the 30-day or in-hospital mortality was 7.3% when managed by endovascular means, whereas the pooled rate for 30-day or in-hospital mortality was 19.0% when subjected to open repair. For acute uncomplicated type B dissection usually treated with blood pressure lowering medications, the pooled 30-day or in-hospital mortality rate was 2.4%. Survival rates at 5 years averaged at 60% (40% mortality). Freedom from any aortic event ranged from 34.0% to 83.9%, underlining an inherent risk of progression and late complications. For chronic complicated type B dissection, the rates of stroke, paraplegia and operative mortality following endovascular repair ranged from 5% to 13%, 2% to 13% and 2 to 13%, respectively, while 5-year survival rates after open repair ranged from 60% to 90%. In chronic uncomplicated type B dissection almost 90% of patients survive initial hospitalization and were subjected to medical management with a 5-year survival of 50-80%. However, up to 20-55% of medically treated patients develop aneurysmal degeneration after 5 years with an unknown risk of rupture.

Conclusions

Currently, the less invasive strategy of endovascular repair (as compared to open surgery) provides improved 30-day or in-hospital survival in the setting of complicated acute type B aortic dissection and may seek broad application. Open surgical aortic reconstruction should be left to experienced aortic centres if endovascular management is not an option.

Long-term experience with the E-vita Open hybrid graft in complex thoracic aortic disease†

OBJECTIVES

The E-vita Open hybrid stent graft is intended to achieve one-stage treatment of the proximal and distal thoracic aorta down to the mid-thoracic level in cases of acute (AAD) or chronic (CAD) type I aortic dissection and complex thoracic aortic aneurysm (TAA). We report our long-term results up to 10-year experience.

METHODS

From February 2005 until March 2015, 178 consecutive patients (mean age 59 ± 11 years) underwent surgery using the E-vita Open hybrid graft for AAD ( n  = 96), CAD ( n  = 43) or TAA ( n  = 39). Pre-, intra- and postoperative variables, influential procedural improvements and follow-up data including aortic remodelling analyses are presented.

RESULTS

Overall 30-day mortality was 10%, 10% for AAD, 7% for CAD and 13% for TAA. Univariable analysis identified low left ventricular ejection fraction, peripheral arterial disease, chronic obstructive pulmonary disease and severely compromised haemodynamics as risk factors for in-hospital death. Logistic regression analysis defined compromised haemodynamics and duration of cardiopulmonary bypass as significant. After 7 years, estimated survival was 55% for AAD, 74% for CAD and 73% for TAA patients. Freedom from aorta-related late death was 94%, 91% in AAD, 100% in CAD and 97% in TAA. Positive or stable aortic remodelling down to the stent graft end was achieved in 92% AAD, 82% in CAD and full aneurysmal exclusion in 88%. Further downstream, negative remodelling was observed in 27% of the AAD, 41% of the CAD and 22% of the TAA patients. Freedom from endovascular intervention downstream was 96% in AAD, 75% in CAD and 74% in TAA patients. Freedom from thoraco-abdominal surgery was 97%, 65% and 93%, respectively.

CONCLUSIONS

The E-vita Open hybrid stent graft renders durable long-term performance without any proximal endoleakage or graft failure over time and represents the ideal landing or docking zone for either thoracic endovascular thoracic repair or thoraco-abdominal surgery, if required. No reinterventions were necessary down to the end of the stent graft, proving that the disease is overcome along the hybrid graft down to mid-thoracic level.

Associated bare stenting of distal aorta with a Djumbodis(®) system versus conventional surgery in type A aortic dissection

BACKGROUND

The effectiveness of additional stenting of the distal aorta as compared to conventional surgery alone in type A aortic dissection (TAD) has yet to be proven.

METHODS

We conducted this multicenter comparative study to evaluate the effects of antegrade bare stenting of the dissected aorta beyond the distal anastomosis with a Djumbodis(®) device system (DDS). Outcomes that were measured included early outcomes, overall mortality from aortic cause and late aortic events including re-interventions. A consecutive series of 134 patients operated on in two participating centers were distributed into study and control groups according to the treatment received: conventional surgery with DDS (DJ group, n=42) or without (control group, n=92).

RESULTS

Operative mortality was 21.4% and 17.6% in the DJ and control groups, respectively (P=0.9), and was within pre-specified alarm lines for both groups. In multivariate analysis, the only independent predictor of operative mortality was the presence of any complication (cardiac tamponade or malperfusion, P=0.05), which occurred more in the DJ group (OR =1.3; non-significant). Sixty patients were included into the matched survivors cohorts study (propensity scoring). The aortic event-free survival at 7 years for early survivors was 77%±10% and 48%±11% in the matched DJ group and control group, respectively (HR =0.66). Late mortality from an aortic cause was 10% and 20% in the matched DJ group and control group, respectively (RR =0.5). Actuarial freedom from aortic or vascular interventions was 71%±10% and 67%±9% in the matched DJ and control group, respectively. Operative mortality was not influenced by the use of DDS as compared to conventional surgery alone for TAD.

CONCLUSIONS

We observed a trend towards better organ perfusion in the DJ group postoperatively, and more aortic events and deaths of aortic cause in the control group during follow-up.

Surgical treatment of complex aneurysms and thoracic aortic dissections with the Frozen Elephant Trunk technique

OBJECTIVE

Report initial experience with the Frozen Elephant Trunk technique.

METHODS

From July 2009 to October 2013, Frozen Elephant Trunk technique was performed in 21 patients (66% male, mean age 56 ± 11 years). They had type A aortic dissection (acute 9.6%, chronic 57.3%), type B (14.3%, all chronic) and complex aneurysms (19%). It was 9.5% of reoperations and 38% of associated procedures (25.3% miocardial revascularization, 25.3% replacement of aortic valve and 49.4% aortic valved graft). Aortic remodeling was evaluated comparing preoperative and most recent computed tomography scans. One hundred per cent of complete follow-up, mean time of 28 months.

RESULTS

In-hospital mortality of 14.2%, being 50% in acute type A aortic dissection, 8.3% in chronic type A aortic dissection, 33.3% in chronic type B aortic dissection and 0% in complex aneurysms. Mean times of cardiopulmonary bypass (152 ± 24 min), myocardial ischemia (115 ± 31 min) and selective cerebral perfusion (60 ± 15 min). Main complications were bleeding (14.2%), spinal cord injury (9.5%), stroke (4.7%), prolonged mechanical ventilation (4.7%) and acute renal failure (4.7%). The need for second-stage operation was 19%. False-lumen thrombosis was obtained in 80%.

CONCLUSION

Frozen Elephant Trunk is a feasible technique and should be considered. The severity of the underlying disease justifies high mortality rates. The learning curve is a reality. This approach allows treatment of more than two segments at once. Nonetheless, if a second stage is made necessary, it is facilitated.

E-vita open plus for treating complex aneurysms and dissections of the thoracic aorta: a NICE medical technology guidance

The E-vita open plus is a one-stage endoluminal stent graft system used for treating complex aneurysms and dissections of the thoracic aorta. The National Institute for Health and Care Excellence (NICE), as a part of its Medical Technologies Evaluation Programme (MTEP), selected this device for evaluation and invited the manufacturer, JOTEC GmbH, to submit clinical and economic evidence. King's Technology Evaluation Centre (KiTEC), an External Assessment Centre (EAC) commissioned by the NICE, independently critiqued the manufacturer's submissions. The EAC considered that the manufacturer had included most of the relevant evidence for the E-vita open plus, based on international E-vita open registry data for 274 patients, but had provided only limited evidence for the comparators. The EAC therefore conducted a systematic review and meta-analysis of all comparators to supplement the information, and found ten additional studies providing outcome data for the three two-stage comparators. The EAC noted that the cost model submitted by the manufacturer did not include key complications during the procedures. The EAC developed a new economic model incorporating data on complications along with their long-term costs. The revised model indicated that the E-vita open plus might not provide cost savings when compared with some of the comparators in the short-term (1 year), but would have high cost savings in the long-term, from the second year onwards. The NICE Medical Technologies Guidance MTG 16, issued in December 2013, recommended the adoption of the E-vita open plus in selected patients within the National Health Service in England.

Aortic arch replacement with frozen elephant trunk-when not to use it

Current scientific evidence suggests the frozen elephant trunk (FET) technique plays an important role in modern aortic arch repair operations, both for aneurysmal disease and acute aortic dissection. Its use in extended aneurysm is generally therapeutic, aiming for complete exclusion of the diseased descending thoracic aorta. In acute aortic dissection type A, the application of FET is more prophylactic in nature, with the aim of preventing late dilatation of the proximal descending thoracic aorta. This review will present the journey of the elephant trunk from its conception to the current available technology. By tracing the historical evolution of the FET technique and prosthesis development, we explore the challenges and limitations of evidence-based surgical research. We present data from our growing experience in aortic arch reconstruction, the results from our latest 27 patients undergoing the 4-branch FET indicating substantially reduced morbidity and mortality (0%) in this complex patient cohort.

Overall Essen's experience with the E-vita open hybrid stent graft system and evolution of the surgical technique

BACKGROUND

The hybrid stent graft prosthesis E-vita open was designed and introduced by us in 2005 to avoid a two-stage surgical approach in the surgical treatment of complex thoracic aortic disease. Experience in ascending aortic and arch replacement with simultaneous stent grafting of the descending aorta was accumulated over the past 8 years. Facilitation of surgical technique by moving the distal suture line from Zone 3 into Zone 2 took place in 2009. We report our mid-term single-center experience comparing both surgical periods.

METHODS

Between January 2005 and July 2013 a total of 132 patients (mean age 59±11 years) underwent one stage surgery for acute (AAD, n=74), chronic aortic dissection (CAD, n=35) or an extensive thoracic aortic aneurysm (TAA, n=23). Patients were separated in two groups according to distal anastomosis level in Zone 2 (Z2, 41/132) and Zone 3 (Z3, 91/132). Outcome, ischemic and operative times as well as adverse events were monitored during follow up.

RESULTS

Overall in-hospital mortality was 13% (17/132) without difference between the groups. However, Zone 2 anastomosis resulted in reduction of cardioplegic arrest (117±39 vs. 147±35 minutes; P<0.001), selective cerebral perfusion (52±15 vs. 68±18 minutes; P<0.001) and visceral ischemic time (51±19 vs. 72±23 minutes; P<0.001). The incidence of postoperative temporary hemodialysis decreased from 40% to 20% in Z2 (P=0.028), postoperative re-exploration rate from 15% to 2% (P=0.037). No difference was found in dissection with complete false lumen thrombosis in 83% (90/109) within 10 days, as well as in TAA, where 100% aneurysm exclusion was observed. Three-year survival, freedom from thoracoabdominal aortic surgery and endovascular repair was 93%, 88%, 88%, respectively. Overall 5-year survival was 76% in AAD, 85% in CAD and 79% in TAA patients.

CONCLUSIONS

The dimension of surgery could be successfully reduced, indicated by significantly shortened ischemic times and postoperative complications. Durable one-stage repair of complex thoracic aortic disease could be achieved in the majority of cases with acceptable mortality. Distal reintervention is infrequent but associated with low risk when indicated.

International E-vita open registry

The E-vita open hybrid stent-graft enables successful one-stage repairs of complex pathologies of the ascending aorta, aortic arch, and descending aorta. To evaluate the efficacy and durability of this treatment concept, the International E-vita open registry (IEOR) was initiated in 2008. 416 patients from 10 European centers were recruited, separated into 138 (33.2%) acute dissection cases, 142 (34.1%) chronic dissection cases, and 136 (32.7%) patients with multisegmental thoracic aneurysmal disease. In-hospital mortality was 16%, 14%, and 13% for each of the three groups, respectively, and stroke and spinal cord injury rates ranged between 5-7% and 3-9%. Survival after 5 years was 79%, 86%, and 78% for acute dissection, chronic dissection, and multisegmental aneurysmal patients, with freedom from open aortic surgery after 5 years at 96%, 94% and 82%. Findings from IEOR demonstrate the importance of the registry as an important tool for developing guidelines and frameworks in the management of this complex pathology.

Elephant trunk technique for hybrid aortic arch repair

The original elephant trunk technique was developed by Borst in 1983 for the treatment of aortic arch aneurysms. This technique reduced operative risks, but was associated with cumulative mortality rates of 6.9 % for the first stage and 7.5 % for the second stage. Patients also waited a long time between two major surgical procedures. Only 50.4 % of patients underwent the second-stage surgery, and there was a significant interval mortality rate of 10.7 %. With the advent of stent-graft techniques, two different hybrid elephant trunk techniques were developed. One technique is first-stage elephant trunk graft placement followed by second-stage endovascular completion. The conventional elephant trunk graft provides a good landing zone for the stent-graft, and endovascular completion is a useful alternative to conventional second-stage surgery. This method has few major complications, and a postoperative paraplegia rate of 1.1 %. The other technique is the frozen elephant trunk technique. This technique eliminates the need for subsequent endovascular completion, and is particularly useful for the treatment of acute type A dissection because it can achieve a secure seal. However, it is associated with a higher rate of spinal cord ischemia than other methods such as the original elephant trunk technique. The left subclavian artery (LSA) is often lost when performing a hybrid elephant trunk procedure. Revascularization of the LSA should be performed to prevent arm ischemia and neurological complications such as paraplegia or stroke, although the level of evidence for this recommendation is low.