Elephant Trunk Technique Research Articles

"Why is frozen elephant trunk better than classical elephant trunk?"

The treatment of complex aortic arch disease, in chronic or acute setting, has always represented a fascinating challenge for the heart surgeon also because, often, the involvement of the aortic arch is associated with a simultaneous involvement of the ascending aorta and of the proximal portion of the descending thoracic aorta. In recent years, there have been many surgical and/or endovascular techniques and approaches in a single step or multiple steps proposed with the aim of treating and simplifying these complex conditions. The first procedure available for this purpose was the conventional elephant trunk technique, proposed by the German surgeon Hans Borst, back in 1983. In the following years, the technique has undergone modifications, up to what is nowadays considered its most modern evolution, represented by the frozen elephant trunk which allows managing the proximal descending thoracic aorta using the antegrade release of a self-expandable stent graft. In this review article, we try to analyze the advantages and drawbacks of both techniques from clinical and practical points of view.

Total arch replacement with the frozen elephant trunk technique for a right-sided aortic arch with a Kommerell diverticulum and aberrant right vertebral artery

The best treatment for a right-sided aortic arch (RAA) and Kommerell diverticulum (KD) has not been determined due to the rarity of these conditions. The current trend in the treatment of this disease is to increase the endovascular approach without a sternotomy. We describe a rare condition with an association of an RAA with a KD of an aberrant left subclavian artery and an anomalous right vertebral artery originating from the aortic arch (AVA). The left vertebral artery was missing. Also, there was an incomplete circle of Willis due to the absence of the left and right posterior communication arteries. Therefore, the AVA was the only artery to supply the vertebral-basilar system. In our case, a simple thoracic endovascular aortic repair was not suitable because of the sharply curved arch and short landing zone. Also, a debranching thoracic endovascular aortic repair was not appropriate because that approach would not permit reconstruction of the AVA. The patient successfully underwent a total arch replacement with the frozen elephant trunk technique. This procedure could be an effective option for patients with RAAs with KDs associated with another arch vessel anomaly.

Incidence of Distal Stent Graft Induced New Entry vs. Aortic Remodeling Associated With Frozen Elephant Trunk

BackgroundThe introduction of the frozen elephant trunk (FET) technique for total arch replacement (TAR) has revolutionized the field of aortivascular surgery by allowing hybrid repair of complex aortic pathologies in a single step through combining an open surgical approach with an endovascular one. FET has been associated with favorable aortic remodeling, however, its is also associated with development of distal stent graft induced new entry (dSINE) tears postoperatively. The rate of aortic remodeling and the incidence of dSINE have been linked together, in addition, there seems to be a relationship between these two variables and FET insetion length as well as graft size.AimsThe scope of this review is to highlight the rate of aortic remodeling as well the incidence of dSINE associated with different FET devices available commercially. This review also aimed to investigate the relationship between aortic remodeling, dSINE, FET insertion length and FET graft size.MethodsWe conducted a comprehensive literature search using multiple electronic databases including PubMed, Ovid, Scopus and Embase in order to collate all research evidence on the above mentioned variables.ResultsThoraflex™ Hybrid Plexus seems to yield optimum aortic remodeling by promoting maximum false thrombosis as well true lumen expansion. Thoraflex Hybrid™ is also associated with the lowest incidence of dSINE post-FET relative to the other FET devices on the market. Aortic remodeling and dSINE do influence each other and are both linked with FET graft length and size.ConclusionThe FET technique for TAR shows excellent aortic remodeling but is associated with a considerable risk of dSINE development. However, Thoraflex™ Hybrid has demonstrated itself to be the superior FET device on the aortic arch prostheses market. Since aortic remodeling, dSINE, FET insertion length and stent graft size are all interconnect, the choice of FET device length and size must be made with great care for optimum results.

Can preoperative features predict residual false lumen remodelling after tear-oriented limited resection for acute type I dissection?

Our goal was to identify the preoperative findings in computed tomography correlated with the postoperative changes of the false lumen (FL) remaining in the descending thoracic aorta following tear-oriented surgery for acute type I dissection. Patients who underwent ascending +/- partial arch replacement, with available preoperative and postoperative late (>1 year) CT scans, were included. Preoperative cross-sectional parameters were measured by the semi-automated centreline method at the level of the anastomosis. The parameters of the patients who presented positive remodelling of the proximal descending thoracic aorta were compared with those of the patients who did not in the late images. Among the included 101 patients, positive remodelling of the proximal descending thoracic aorta was observed in 46.5%, of which 76.6% extended downwards to the middle descending thoracic aorta. In the univariable analysis, an FL area ratio <50% (P < 0.001), a circumferential ratio of dissection <50% (P = 0.028), an FL width <20 mm (P = 0.008) at the distal anastomotic zone and not leaving residual arch branches having patent false lumens (P = 0.005) correlated with positive remodelling. The number of fulfilled above-mentioned features revealed a better correlation, which was stronger in patients without Marfan syndrome and in those older than 50 years. The cross-sectional extent of dissection at the presumed distal anastomotic zone is associated with descending thoracic aorta positive remodelling following tear-oriented replacement for acute type I aortic dissection. Considering the anatomical features in determining the extent of aortic replacement, some of the non-Marfan elderly patients can be spared from aggressive total arch replacement with the frozen elephant trunk technique.

E-Vita OPEN NEO Hybrid Stent Graft: A New Frontier for Total Arch Replacement

The ever-changing landscape of aortic arch surgery necessitates a constant update on the available devices and technologies for the contemporary management of complex aortic diseases. The E-Vita OPEN NEO hybrid stent graft system offers a unique approach for aortic arch replacement with the frozen elephant trunk technique. In contrastto its predecessors and other commercially available devices, it fits to each individual patient's needs by allowing for more proximal graft anastomosis. We sought to present our initial experience with the novel E-Vita OPEN NEO hybrid stent graft system focusing on its description, optimal graft selection, operative technique, and results in a clinical setting. We prospectively collected data on all patients in whom the E-Vita OPEN NEO device was used between October 2020 and May 2021. The primary outcome was perioperative or with 30-day mortality. Secondary outcomes were the incidence of neurologic complications (stroke and spinal cord ischemia) and endoleak on a postoperative computed tomography angiography. During the study period, six patients received the novel hybrid stent device. The mean patient age was 59.3±13.3years and 83% were male. Two patients were operated on an emergent setting due to acute Stanford type A aortic dissection and there were two reoperations in patients with a history of previous repaired type A dissection. There was no perioperative or 30-day mortality and none of the patients exhibited adverse neurologic events. Two patients required completion thoracic endovascular repair due to type Ib endoleak. One patient died after a prolonged stay in the intensive care unit due to pneumonia and multiorgan failure. This novel device adapts to each patient's characteristics and offers a curative option for acute and chronic aortic arch and descending aortic conditions such as aneurysmal disease and aortic dissection. In addition, it offers an excellent landing station for potential endovascular therapies and allows for complete aortic remodeling.

Institutional practice in sizing of the hybrid prosthesis in frozen elephant trunk surgery.

The frozen elephant trunk (FET) technique for total arch replacement (TAR) is widely used for repair of aortic arch dissections and aneurysms. Despite its widespread adoption, there are no international or regional guidelines for the sizing of FET prostheses in TAR. We seek to highlight the heterogeneity thereof and pave the way for evidence-based guidelines to advise FET prosthesis sizing in TAR. An online questionnaire was sent to 22 specialist aortic surgeons from 13 different countries across North America, Europe, Asia, and Australia, inquiring about each surgeon's approach to FET prosthesis sizing. The results were then pooled for frequency analysis. All 22 surgeons responded to the questionnaire. Zone 2 is preferred implantation zone for AAD, CAD, and TAA (selected by 72.7%, 72.7%, and 68.2% respectively). The maximal diameter of the true lumen in the DTA is the most common index measurement for AAD and CAD (40.9% and 59.1%, respectively). Stent-graft diameters equal to the index measurement is the most common approach for AAD and CAD (77.3% and 45.5%, respectively) while 59.1% of surgeons oversize the index diameter by 10% for TAA; 100 mm is the preferred length for 50.0%, 27.3%, and 40.9% of surgeons in AAD, CAD, and TAA respectively. There is considerable heterogeneity in sizing practices for FET prostheses internationally, with variable evidence for its impact on clinical outcomes. This issue would be aided by the development of evidence-based guidelines to inform clinical decision making.

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

BackgroundThe 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 MethodsPre-, 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.ResultsData 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.DiscussionThoraflex™ 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.ConclusionThoraflex™ 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.

Total arch replacement using frozen elephant trunk technique with Frozenix for distal aortic arch aneurysms.

OBJECTIVESTotal arch replacement (TAR) using an endovascular approach has been initially introduced as the frozen elephant trunk technique (FET). In our institute, TAR using the FET with Frozenix has been used as the first-line treatment for distal aortic arch aneurysms since 2014. This study aimed to evaluate the early and long-term outcomes and demonstrate the efficacy of this procedure.METHODSBetween 2014 and 2021, 121 consecutive patients were treated with TAR using the FET with Frozenix for distal aortic arch aneurysms. Early and long-term outcomes were retrospectively analysed.RESULTSThe 30-day mortality rate was 2.5% (3/121). Of postoperative complications, paraplegia due to spinal cord injury occurred in 2 (1.7%) patients, stroke in 12 (9.9%) and acute renal failure in 10 (8.3%). At follow-up, 23 secondary aortic interventions were required and 8 (6.6%) patients underwent intended secondary thoracic endovascular aortic repair for residual descending aortic aneurysm. Late and aortic-related deaths occurred in 16 (13.2%) and 4 (3.3%) patients, respectively. The overall long-term survival rates at 1, 3 and 5 years were 87.6%, 83.1% and 65.4%, respectively, while the rates of freedom from aortic-related death at 1, 3 and 5 years were 95.7%, 95.7% and 84.8%, respectively.CONCLUSIONSTAR using the FET with Frozenix for distal aortic arch aneurysms has acceptable early mortality and morbidity. Spinal cord injury and paraplegia occur less frequently than previously reported. The technique has satisfactory long-term survival and freedom from aortic-related death.

Does systemic immune-inflammation index predict the short outcomes after an acute type A aortic dissection repair? Promising biomarker for acute aortic syndrome.

The retrospectively presented by Xu et al. assessed the value of the systemic immune-inflammation index (SII) in the prediction of short-term outcomes in patients undergoing surgery for acute type A aortic dissection (ATAAD). The authors concluded that SII is a reliable biomarker that can predict postoperative short-term outcomes and this marker could be potentially applied to stratification and patient selection with ATAAD. Although the study is retrospective, it is well-matched and conducted in a large volume center and the surgical technique was standard for all procedures. In addition, there was no statistical difference in cardiopulmonary bypass, aortic cross-clamp and deep hypothermic time, comorbidities, blood and blood products transfusion between the study groups. In addition, 90.7% of patients underwent elephant trunk technique for ATAAD repair, while the 30-day mortality and postoperative temporary and permanent neurological dysfunctions were 14.8% and 11.1%, respectively. Randomized controlled and prospective studies are warranted to clarify these well-documented results to apply this useful biomarker in clinical practice for patients with the acute aortic syndrome.

Non-A non-B acute aortic dissection with entry tear in the aortic arch.

OBJECTIVESOur aim was to describe the outcomes of the latest treatment options of acute non-A non-B aortic dissection involving an entry tear in the aortic arch.METHODSIncluded were patients who presented between January 2001 and February 2020 with a non-A non-B aortic dissection involving the aortic arch but not the ascending aorta and with the most proximal entry tear located within the aortic arch between the innominate and left subclavian artery. Clinical data and operative details were retrieved from medical histories and surgical protocols. Preoperative, postoperative and follow-up computed tomography angiography scans were analysed.RESULTSWe analysed a total of 39 patients [median age 62 (52; 67) years, men 76.9%] with non-A non-B arch entry aortic dissections type. They underwent 15 thoracic endovascular aortic repairs, 20 frozen elephant trunk implantations, 1 hybrid arch replacement, or 1 conventional arch replacement. Two patients were managed conservatively. Twelve (31%) patients underwent emergent intervention, 12 (31%) were treated invasively within 2 weeks. Another 2 (5%) and 9 (23%) patients were treated 2 and 4 weeks after dissection occurred, respectively. Six (15%) patients presented with an impending aortic rupture, while 19 (49%) had at least one malperfused organ. Four patients (27%) died after thoracic endovascular aortic repair; the 30-day mortality following frozen elephant trunk was 0%.CONCLUSIONSNon-A non-B acute aortic dissection reveals a frequently complicated course requiring emergency intervention. The majority of patients required aortic arch repair within the first 2 weeks. Total arch replacement with the frozen elephant trunk technique seems to be low procedural mortality, and may become the treatment of choice in arch entry non-A non-B aortic dissection.

Frozen Elephant Trunk Completion: Endovascular Extension in The Distal Thoracic Aorta.

Complex pathologies involving the aortic arch can be treated using the frozen elephant trunk (FET) technique, which is versatile and continues to be improved with different innovations to further reduce, for example, circulatory arrest time and the need for hypothermia. FET may or may not be a definitive repair, however. Distal extension or completion-especially endovascular-is common but not well described in the literature. This review describes the considerations that are necessary during FET planning and preparation, how pathology specifics and sizing decisions will affect the subsequent need for treatment, and how outcomes might be better reported to improve understanding of the advantages and limitations of the technique. This literature review was performed to identify reports of second-stage endovascular completion after FET repair, and included any literature that described such interventions after index FET, for any aortic arch pathology. Secondary intervention after FET is an important parameter to establish the success or failure of the index procedure. However, unplanned extensions are often reported with insufficient detail and follow up, and studies rarely differentiate between unplanned or adjunctive procedures. In addition, prediction of the need for extension is complicated by the response of the pathology to the index procedure. FET is a versatile, established surgical technique that allows for several applications in different pathologies and innovative adaptations. How, when, and why FET is extended needs to be reported in greater detail, with specific consideration given to the interaction of FET and endovascular devices in sizing, integrity, and possible complications.

Modification of Frozen Elephant Trunk Technique for Acute Type-A Aortic Dissection - A Case Report

Acute type-A aortic dissection (ATAAD) is a dreadfully fatal cardiovascular emergency. The mortality rate among medically treated patients is 50% within two days. Surgery is the gold standard and urgent surgical treatment is indicated for all patients, except for those who are moribund or severely comorbid. However, early mortality after operation remains high (9–25%). We hereby present a case of 22 years young, male, Marfan patient with a family history of ATAAD treated successfully by us at Square Hospital Ltd by modified Bentall’s procedure with total arch replacement with Frozen Elephant Trunk (FET) technique.&#x0D; University Heart Journal 2022; 18(1): 65-70

Morphometric Predictors of Aortic Remodeling after Frozen Elephant Trunk Repair of Type A Dissection

We analyzed the predictors of postoperative aortic remodeling after the frozen elephant trunk technique for type A dissection. This retrospective study cohort comprised 20 patients who underwent the frozen elephant trunk technique for type A dissection. The incidence of aortic remodeling was evaluated at 4 levels: middle of the frozen elephant trunk, distal end of the frozen elephant trunk, 10th thoracic vertebra, and proximal to the celiac artery. Several parameters of the residual dissected aorta were analyzed at these 4 levels, and the predictors of aortic remodeling were investigated. The incidence of aortic remodeling was 85% at the middle of the frozen elephant trunk, 70% at the distal end of the frozen elephant trunk, 50% at the 10th thoracic vertebra, and 35% proximal to the celiac artery. In a total of 80 computed tomography images, there were significant differences between the aortic remodeling and nonremodeling groups in the true lumen diameter, false lumen diameter, true lumen/aortic diameter ratio, true lumen area, true lumen/aortic area ratio, and 2 parameters explaining the shape of the true lumen (created using elliptic Fourier analysis). Multivariate analysis revealed that the independent predictors of aortic remodeling were the true lumen/aortic area ratio and principal component 1. There were high incidences of aortic remodeling at the middle and distal end of the frozen elephant trunk. Multivariate analysis showed that the true lumen/aorta area ratio and the shape of the true lumen may be important predictors of aortic remodeling.

Risk factors for stroke after total aortic arch replacement using the frozen elephant trunk technique.

OBJECTIVESThis study aimed to analyse risk factors for postoperative stroke, evaluate the underlying mechanisms and report on outcomes of patients suffering a postoperative stroke after total aortic arch replacement using the frozen elephant trunk technique.METHODSTwo-hundred and fifty patients underwent total aortic arch replacement via the frozen elephant trunk technique between March 2013 and November 2020 for acute and chronic aortic pathologies. Postoperative strokes were evaluated interdisciplinarily by a cardiac surgeon, neurologist and radiologist, and subclassified to each’s cerebral territory. We conducted a logistic regression analysis to identify any predictors for postoperative stroke.RESULTSOverall in-hospital was mortality 10% (25 patients, 11 with a stroke). A symptomatic postoperative stroke occurred in 42 (16.8%) of our cohort. Eight thereof were non-disabling (3.3%), whereas 34 (13.6%) were disabling strokes. The most frequently affected region was the arteria cerebri media. Embolism was the primary underlying mechanism (n = 31; 73.8%). Mortality in patients with postoperative stroke was 26.2%. Logistic regression analysis revealed age over 75 (odds ratio = 3.25; 95% confidence interval 1.20–8.82; P = 0.021), a bovine arch (odds ratio = 4.96; 95% confidence interval 1.28–19.28; P = 0.021) and an acute preoperative neurological deficit (odds ratio = 19.82; 95% confidence interval 1.09–360.84; P = 0.044) as predictors for postoperative stroke.CONCLUSIONSStroke after total aortic arch replacement using the frozen elephant trunk technique remains problematic, and most lesions are of embolic origin. Refined organ protection strategies, and sophisticated monitoring are mandatory to reduce the incidence of postoperative stroke, particularly in older patients presenting an acute preoperative neurological deficit or bovine arch.

How Will the Elephant Trunk Technique Evolve in Thoracic Aortic Aneurysm Repair?

Since Dr Borst first introduced the elephant trunk (ET) procedure for repair of extensive aortic aneurysms in 1982, this approach has undergone several technical modifications and achieved improved surgical outcomes during the past 4 decades. However, with the advent of endovascular and hybrid therapies, especially the spread of the frozen elephant trunk (FET) technique, the role of the conventional ET technique in the repair of diffuse aortic aneurysms has been obfuscated with constant doubts and questions.

Surgical outcomes of total arch replacement with modified elephant trunk technique in type A aortic dissection: insights from single-center experience.

Total arch replacement with modified elephant trunk technique plays an important role in treating acute type A aortic dissection in China. We aim to summarize the therapeutic effects of this procedure in our center over a 17-year period. Consecutive patients treated at our hospital due to type A aortic dissection from January 2004 to January 2021 were studied. Relevant data of these patients undergoing total arch replacement with modified elephant trunk technique were collected and analyzed. A total of 589 patients were included with a mean age of 53.1 ± 12.2 years. The mean of cardiopulmonary bypass, cross-clamping, and selected cerebral perfusion time were 199.6 ± 41.9, 119.0 ± 27.2, and 25.1 ± 5.0 min, respectively. In-hospital death occurred in 46 patients. Multivariate analysis identified four significant risk factors for in-hospital mortality: preexisting renal hypoperfusion (OR 5.43; 95% CI 1.31 - 22.44; P = 0.020), cerebral malperfusion (OR 11.87; 95% CI 4.13 - 34.12; P < 0.001), visceral malperfusion (OR 4.27; 95% CI 1.01 - 18.14; P = 0.049), and cross-clamp time ≥ 130 min (OR 3.26; 95% CI 1.72 - 6.19; P < 0.001). The 5, 10, and 15 years survival rates were 86.4%, 82.6%, and 70.2%, respectively. Total arch replacement with modified elephant trunk technique is an effective treatment for acute type A aortic dissection with satisfactory perioperative results. Patients with preexisting renal hypoperfusion, cerebral malperfusion, visceral malperfusion, and long cross-clamp time are at a higher risk of in-hospital death.

Total Aortic Arch Replacements With a 4 Branched Frozen Elephant Trunk (FET) Graft in Acute Aortic Dissection (DeBakey type I)

Total Aortic Arch Replacements With a 4 Branched Frozen Elephant Trunk (FET) Graft in Acute Aortic Dissection (DeBakey type I)

The Frozen Elephant Trunk Technique Combined with Beating Heart in Complicated Type B Dissection

The Frozen Elephant Trunk Technique Combined with Beating Heart in Complicated Type B Dissection

Aortic Valve and Arch Replacements in a High-Risk Patient with Essential Thrombocythemia

Reports of the clinical results of cardiac surgery in patients with Essential Thrombocythemia (ET) are rare. In addition, cases of aortic arch aneurysm in ET have not been previously reported. We present a successful aortic valve and arch replacements with the frozen elephant trunk technique using hypothermic circulatory arrest in an ET patient with grade 3 aortic regurgitation and arch aneurysms. Reducing platelet count via the administration of anagrelide and the careful balancing of antiplatelets and anticoagulants is essential in determining the outcome of surgery.

Hybrid Approach in Acute and Chronic Aortic Disease

The management of patients with aortic disease that involves the ascending aorta, the aortic arch, and the descending aorta represent a surgical challenge. Open surgical repair remains the gold standard for aortic arch pathologies. However, this operation requires a cardiopulmonary bypass and a period of profound hypothermia and circulatory arrest, which carries a substantial rate of mortality and morbidity. For these reasons, hybrid arch repair that involves a combination of open surgery with endovascular aortic stent graft placement has been introduced as a therapeutic alternative for those patients deemed unfit for open surgical procedures. Hybrid repair requires varying degrees of invasiveness and can be performed as a single-stage procedure or as a two-stage procedure. The choice of the technique is multifactorial, depending on the characteristics of the diseased arch with regard to position of the stent graft proximal landing zone, patient fitness and comorbid status, as well as surgical expertise and hospital facilities. Among the evolving hybrid procedures is the so-called “frozen” or stented elephant trunk technique. Adapted from the classical elephant trunk technique, this approach facilitates the repair of a concomitant aortic arch and proximal descending aortic aneurysms in a single stage under circulatory arrest. This technique is increasingly being used to treat extensive thoracic aortic disease and has shown promising results.