A New Aortic Arch Inclusion Technique With Frozen Elephant Trunk for Type A Aortic Dissection

A new minimal invasive technique with in-situ stent-graft fenestration for type A aortic dissection

Background

Aortic surgery successfully improves the prognosis of patients with type A aortic dissection. However, total arch replacement and reconstruction remain challenging. This study presents a new surgical modality, the in-situ stent-graft fenestration (ISSF) technique, for simplifying aortic arch reconstruction and assesses its short-term efficacy and safety in patients with type A aortic dissection.

Methods

Data from 177 patients with type A aortic dissection who underwent aortic arch reconstruction were retrospectively analyzed. Sun's procedure was performed in 90 patients and ISSF was performed in the other 87.

Results

The in-hospital mortality rate was 7.8% in the Sun's procedure group and 3.4% in the ISSF group (p = 0.357). Compared to the Sun's procedure group, the ISSF group had significantly shorter surgical duration, cardiopulmonary bypass time, circulatory arrest time, mechanical ventilation time, and aortic cross-clamp time (p < 0.05). Additionally, intraoperative blood loss was lower in the ISSF group than in the Sun's procedure group (p < 0.05). Patients who underwent ISSF also had a lower incidence of postoperative complications, including lung injury, renal failure, peripheral nerve injury, and chylothorax, than those who underwent Sun's procedure (p < 0.05). During the 6-month follow-up period after surgery, both groups showed significant improvements in the true lumen diameter of the descending thoracic aorta post-operation compared with the pre-operation measurements; meanwhile, the false lumen diameter decreased (p < 0.05).

Conclusions

The ISSF technique appears to be an effective and safe alternative to conventional surgical procedures for patients with type A aortic dissection, with the potential to simplify the procedure, shorten the operation time, and yield satisfactory operative results. However, further investigation is needed to determine its long-term benefits.

Experience with aortic arch inclusion technique using artificial blood vessel for type A aortic dissection: an application study

BACKGROUND

This study aimed to elucidate the methodology and assess the efficacy of the aortic arch inclusion technique using an artificial blood vessel in managing acute type A aortic dissection (ATAAD).

METHODS

We conducted a retrospective review of 18 patients (11 males and 7 females, average age: 56.2 ± 8.6 years) diagnosed with ATAAD who underwent total aortic arch replacement (TAAR) using an artificial vascular "inclusion" between June 2020 and October 2022. During the operation, deep hypothermic circulatory arrest (DHCA) and selective antegrade cerebral perfusion (ACP) of the right axillary artery were employed for brain protection. The 'inclusion' total aortic arch replacement and stented elephant trunk (SET) surgery were performed.

RESULTS

Four patients underwent the Bentall procedure during the study, with one additional patient requiring coronary artery bypass grafting (CABG) due to significant involvement of the right coronary orifice. Three patients died during postoperative hospitalization. Other notable complications included two cases of postoperative renal failure necessitating continuous renal replacement therapy (CRRT), one case of postoperative double lower limb paraplegia, and one case of cerebral infarction resulting in unilateral impairment of the left upper limb. Eleven patients underwent computed tomography angiography (CTA) examinations of the aorta three months to one-year post-operation. The CTA results revealed thrombosis in the false lumen surrounding the aortic arch stent in seven patients and complete thrombosis of the false lumen around the descending aortic stent in eight patients. One patient had partial thrombosis of the false lumen around the descending aortic stent, and another patient's false lumen in the thoracic and abdominal aorta completely resolved after one year of follow-up.

CONCLUSIONS

Incorporating vascular graft in aortic arch replacement simplifies the procedure and yields promising short-term outcomes. It achieves the aim of total arch replacement using a four-branch prosthetic graft. However, extensive sampling and thorough, prolonged follow-up observations are essential to fully evaluate the long-term results.

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.

Systematic total arch replacement with thoraflex hybrid graft in acute type A aortic dissection: A single centre experience

Introduction

In the last two decades, a more aggressive approach has been encouraged to treat patients with acute type A aortic dissection (ATAAD), extending the repair to the aortic arch and proximal descending thoracic aorta with the frozen elephant trunk (FET) implantation. Here, we report our single-centre experience with the FET technique for the systematic treatment of emergency type A aortic dissection.

Materials and methods

Between December 2017 and January 2022, 69 consecutive patients were admitted with ATAAD; of those, 66 patients (62.9 ± 10.2 years of age, 81.8% men) underwent emergency hybrid aortic arch and FET repair with the multibranched Thoraflex hybrid graft and were enrolled in the study. Primary endpoints were 30 days- and in-hospital mortality. Secondary endpoints were postoperative morbidity and follow-up survival. To better clarify the impact of age on surgical outcomes, we have divided the study population into two groups: group A for patients <70 years of age (47 patients), and group B for patients ≥70 years (19 patients). Time-to-event analysis has been conducted using the Log-rank test and is displayed with Kaplan-Meier curves. A multiple Cox proportional Hazard model was developed to identify predictors of long-term survival with a stepwise backward/forward selection process.

Results

30-days- and in-hospital mortality were 10.6 and 13.6%, respectively. Stroke occurred in three (4.5%) patients. Two (3.0%) patients experienced spinal cord ischemia. We did not find any statistically significant difference between the two groups in terms of main post-operative outcomes. The multivariable Cox proportional hazard model showed left ventricular ejection fraction (HR: 0.83, 95% CI: 0.79–0.92, p < 0.01), peripheral vascular disease (HR: 15.8, 95% CI: 3.9–62.9, p < 0.01), coronary malperfusion (HR: 0.10, 95% CI: 0.01–0.77, p =0.03), lower limbs malperfusion (HR: 5.1, 95% CI: 1.10–23.4, p = 0.04), and cardiopulmonary bypass time (HR: 1.02, 95% CI: 1–1.04, p = 0.01) as independent predictors of long term mortality.

Conclusions

Frozen elephant trunk repair to treat emergency type A aortic dissection appears to be associated with good early and mid-term clinical outcomes even in the elderly.

Ministernotomy approach to aortic arch inclusion and frozen elephant trunk in the treatment of acute Stanford A aortic dissection

This study aimed to report our results of ministernotomy approach to Liu’s aortic root repair technique, Liu’s aortic arch inclusion technique with frozen elephant trunk (FET) in the treatment in type A aortic dissection (TAAD). We retrospectively analyzed data on 68 Stanford A aortic dissection patients from October 2017 to March 2020. All patients underwent Liu’s aortic root repair technique, Liu’s aortic arch inclusion technique with FET and mild-moderate hypothermic circulatory arrest combined with ministernotomy approach. 154 TAAD patients between January 2014 and December 2016 underwent complete sternotomy were selected as control group. Clinical characteristics, data during operation, in-hospital and postoperative outcomes of these patients were observed. The mean hypothermic circulatory arrest time in ministernotomy Patients was 39.3 ± 7.9 min, aortic cross-clamp time was 105.9 ± 12.8 min, cardiopulmonary bypass time was 152.8 ± 24.3 min. Three patients died of multiple organ dysfunction syndrome in ministernotomy Patients. Perioperative temporary neurological dysfunction occurred in three (4.41%) patients, and 53 (77.9%) patients did not require any blood product transfusion during and after operation in ministernotomy Patients. Postoperative CT angiography (CTA) examination at 6-32 months showed excellent outcomes except in three (4.41%) cases where arch false lumen patency persisted. The Liu’s aortic root repair technique, Liu’s aortic arch inclusion technique with FET and mild-moderate hypothermia circulatory arrest simplify the surgical procedure and reduce bleeding, which can be accomplished through minimally invasive approach.

Aortic remodeling, distal stent-graft induced new entry and endoleak following frozen elephant trunk: A systematic review and meta-analysis

BACKGROUND

The introduction of the frozen elephant trunk (FET) technique for total arch replacement (TAR) has revolutionized the field of aortovascular surgery. However, although FET yields excellent results, the risk of certain complications requiring secondary intervention remains present, negating its one-step hybrid advantage over conventional techniques. This systematic review and meta-analysis sought to evaluate controversies regarding the incidence of FET-related complications, with a focus on aortic remodeling, distal stent-graft induced new entry (dSINE) and endoleak, in patients with type A aortic dissection (TAAD) and/or thoracic aortic aneurysm.

MATERIALS AND METHODS

A comprehensive literature search was conducted using multiple electronic databases including EMBASE, Scopus, and PubMed/MEDLINE to identify evidence on TAR with FET in patients with TAAD and/or aneurysm. Studies published up until January 2022 were included, and after applying exclusion criteria, a total of 43 studies were extracted.

RESULTS

A total of 5068 patients who underwent FET procedure were included. The pooled estimates of dSINE and endoleak were 2% (95% confidence interval [CI] 0.01-0.06, I²  = 78%) and 3% (95% CI 0.01-0.11, I²  = 89%), respectively. The pooled rate of secondary thoracic endovascular aortic repair (TEVAR) post-FET was 7% (95% CI 0.05-0.12, I²  = 89%) while the pooled rate of false lumen thrombosis at the level of stent-graft was 91% (95% CI 0.75-0.97, I²  = 92%). After subgroup analysis, heterogeneity for distal stent-graft induced new entry (dSINE) and endoleak resolved among European patients, where Thoraflex Hybrid (THP) and E-Vita stent-grafts were used (both I²  = 0%). In addition, heterogeneity for secondary TEVAR after FET resolved among Asians receiving Cronus (I²  = 15.1%) and Frozenix stent-grafts (I²  = 1%).

CONCLUSION

Our results showed that the FET procedure in patients with TAAD and/or aneurysm is associated with excellent results, with a particularly low incidence of dSINE and endoleak as well as highly favorable aortic remodeling. However the type of stent-graft and the study location were sources of heterogeneity, emphasizing the need for multicenter studies directly comparing FET grafts. Finally, THP can be considered the primary FET device choice due to its superior results.

Zone proximalization in frozen elephant trunk: what is the optimal zone for open intervention? A systematic review and meta-analysis

INTRODUCTION

The treatment of complex aortic lesions involving the ascending, arch, and proximal descending aorta, remains challenging for surgeons despite the evolution of surgical techniques and aortic prostheses over decades. The frozen elephant trunk (FET) approach offers a one-stage repair of this entity of aortic pathologies. The main scope of this systematic review and meta-analysis is to evaluate the clinical outcomes and effectiveness of FET.

EVIDENCE ACQUISITION

In a systematic review, multiple electronic databases including EMBASE, Scopus, and PubMed/MEDLINE were searched from inception to June 2021 to identify relevant studies reporting on outcomes of total arch replacement (TAR) with FET.

EVIDENCE SYNTHESIS

Eighty-five studies met inclusion criteria, encompassing 10960 patients. Meta-analysis was conducted using the R-studio (RStudio, Boston, MA, USA) and STATA software (StataCorp LLC, College Station, TX, USA). The pooled in-hospital mortality rate was 7% (95% CI 0.05-0.09; I²=76%) and 12% for renal failure (95% CI 0.09-0.15; I²=88%), while the rates for paraplegia and cerebrovascular accidents were 3% (95% CI 0.02-0.04; I²=0%) and 6% (95% CI 0.05-0.08; I²=73%), respectively. Lower heterogeneity was attained after the stratification by the aortic pathologies, except for the renal failure. The distal anastomosis of the stent in zone 2 was significantly correlated with a lower renal failure development compared to zone 3 (odds ratio 0.52; 95% CI 0.33-0.82; P=0.069; I²=0%).

CONCLUSIONS

Our results indicate that the morbidities and mortality following TAR with FET were acceptable. We also associated the distal anastomosis in zone 2 with fewer renal failure development compared to that in zone 3.

Four-branched graft inversion technique for the distal anastomosis in acute aortic dissection

Background

Distal anastomosis bleeding is an issue during total arch replacement with the frozen elephant trunk technique. We used the 4-branched graft inversion technique for the distal anastomosis in acute aortic dissection. The aim was to evaluate the feasibility and benefits of the technique used during the frozen elephant trunk procedure for acute aortic dissection.

Methods

From January 2017 to July 2019, 109 patients underwent total arch replacement for type A acute aortic dissections. Patients were divided according to the technique used for the distal anastomosis as follows: group G (n = 57; 4-branched graft inversion technique) and group C (n = 52; conventional method with Teflon felt). The postoperative variables were analysed.

Results

The hospital mortality rate was 9.2% (10/109). The mean cardiopulmonary bypass, cardiac arrest, and circulatory arrest times were 234.95 ± 71.88 min, 168.25 ± 61.33 min, and 39.19 ± 9.45 min, respectively. The circulatory arrest and cardiac arrest times were shorter in the graft inversion group than in the conventional group (36.46 ± 7.88 min vs. 42.19 ± 10.17 min, P = 0.001 and 156.21 ± 55.99 min vs. 181.44 ± 64.68 min, P = 0.031, respectively). There were 7 cases of stroke (6.4%) and 5 cases of paraplegia (4.6%). Additionally, 13 patients (11.9%) required temporary continuous renal replacement therapy. Respiratory failure occurred in 19 patients (17.4%). There were no significant differences in postoperative complications between the two groups.

Conclusions

The 4-branched graft inversion technique provides effective and confirmed haemostasis during total aortic arch replacement using the frozen elephant trunk procedure.

Frozen Elephant Trunk Technique in Acute Type A Aortic Dissection: Is It for All?

Acute type A aortic dissection (ATAAD) is an indisputable emergency with very poor outcomes without surgical treatment. Although the aortic arch is often involved in the aortic dissection, its optimal management during surgical therapy remains uncertain. A conservative tear-oriented approach has traditionally been adopted, limiting the procedure to the ascending aorta (or hemiarch) replacement. However, dilation of the residual dissected aorta and subsequent rupture may occur, requiring further intervention in the future. In the last two decades, the frozen elephant trunk (FET) technique has become a valid and attractive option to treat aortic disease when the arch and the thoracic aorta are involved, both in elective and in emergency settings. Here, we report a review of the contemporary literature regarding the short- and long-term outcomes of the FET technique in ATAAD repair.

Non-A non-B aortic dissection: A literature review

Non-A non-B aortic dissections are an infrequent occurrence and represent a small proportion of aortic dissections. Treating this life-threatening medical emergency often requires surgeons to undertake some one of the most challenging surgical or endovascular cases in medicine. This literature review aims to define and classify non-A non-B dissections, describe their epidemiology as well as their pathology. This review also aims to discuss the range of surgical techniques employed in their treatment and management and to investigate the patient outcomes associated with each technique.

Outcomes of Liu's aortic root repair and valve preservation in patients with type A dissection and aortic regurgitation

OBJECTIVES

To evaluate short- and medium-term outcomes following Liu's aortic root repair and valve preservation in patients with acute type A aortic dissection complicated by moderate-to-severe aortic regurgitation (AR).

METHODS

From October 2011 to July 2018, a total of 324 consecutive patients underwent emergency surgery for acute type A aortic dissection. There were 122 patients (38%) with moderate-to-severe AR, of whom 82 (67%) underwent Liu's aortic root repair and valve preservation. Aortic computed tomography angiography and echocardiography were performed at discharge, 6 and 12 months postoperatively, and annually thereafter. We focused on assessing the survival and aortic root and valve durability in the 82 patients.

RESULTS

The 30-day, 1-year, 3-year and 6-year survival estimates were 94%, 90%, 85% and 81%, respectively. At a median follow-up of 36.5 (interquartile range 24.9-50.9) months, all patients were free from reoperation. No residual false lumens in the aortic root, recurrent aortic root dissections or aortic root pseudoaneurysms were observed during the follow-up period. Only 1 patient (1%) presented with moderate AR at 6 months, which remained asymptomatic with no significant changes over a 3-year period. The remaining patients showed satisfactory valve function with an AR grade of mild (27%) or trace or none (72%). In the competing risk analysis, the incidence of recurrence of AR was 2% at 8 years.

CONCLUSIONS

Liu's aortic root repair and valve preservation is a safe and effective operative strategy that achieves favourable short- and medium-term outcomes for acute type A aortic dissection with moderate-to-severe AR.

A New Aortic Arch Inclusion Technique with Frozen Elephant Trunk for Aortic Arch Aneurysm Treatment

Various surgical techniques have been proposed for treating aortic arch aneurysm (AAA); however, the optimal treatment has not been well defined. This study introduces a new aortic arch inclusion technique with frozen elephant trunk (FET) for AAA treatment.A retrospective analysis was performed among 22 patients for AAA surgical treatment between March 2010 and March 2019. Patients were classified into Z1, Z2, and Z3 groups based on the origins of aneurysms. A stent graft with a 10 cm stented graft and 5-9 cm proximal vascular prosthesis was released into the descending thoracic aorta as FET through an incision in the aortic arch. The proximal vascular prosthesis was retracted into the aortic arch, trimmed to expose the orifices of the brachiocephalic vessels, and sutured inside the aortic arch using the inclusion technique. The proximal sealing location of the vascular graft was tailored to cover the origins of aneurysms.There was no 30-day mortality. No patient had postoperative stroke or paraplegia. Complete aneurysm thrombosis was achieved in all patients. One patient died of severe respiratory tract stenosis 3 months postoperatively. All other 21 patients were alive during 53.3 ± 36.5-month follow-up. Computed tomography angiography was obtained in 15 patients during follow-up. Endoleak was observed in one patient, and the other 14 patients were free from aneurysm-related or graft-related complications during follow-up.The aortic arch inclusion technique with FET provides an alternative technique in treating AAA with satisfactory mid-term follow-up results. A larger patient population with long-term follow-up results is warranted.