Impact of the Frozen Elephant Trunk Technique on Total Aortic Arch Replacement

Hybrid total arch replacement via ministernotomy for Stanford type A aortic dissection

Background

Type A aortic dissection (TAAD) is a cardiovascular emergency condition with high mortality rate. Hybrid total aortic arch replacement using endovascular graft for the descending aorta repair results in favorable outcomes and has been recommended as an alternative procedure for the higher-risk category patients. Our institution started applying the upper ministernotomy incision technique for the hybrid procedures back in 2018.

Methods

We collected patients who underwent hybrid total arch replacement (HTAR) via ministernotomy (96) and total arch replacement with frozen elephant trunk (TAR + FET) procedures (99), between 2018 and 2021. The baseline information, intraoperative and postoperative characteristics have been compared. Kaplan-Meier analysis was used for survival evaluation. Cox regression were applied to identify the independent predictor of mortality.

Results

The baseline characteristics between the two patient groups were compared and found similar, except that RBC counts were higher (p = 0.038) and the ascending aorta diameter was smaller (P = 0.019) in the "HTAR" group relative to the "TAR + FET" group. The cardiopulmonary bypass time (P < 0.001), the aortic cross clamp time (P < 0.001), the operation duration (P = .029), ICU (P = 0.037) and postoperative hospital stay (P = 0.002) were shorter in the "HTAR" group. The "HTAR" group exhibited also significantly lower levels of intraoperative transfusion (all <0.001) characteristics than the "TAR + FET" group. The hospital mortality and 1-year mortality revealed similar patterns in both groups.

Conclusion

HTAR via ministernotomy have similar short term prognosis, and also reduced the ICU and postoperative hospital stay. In all, The application of the ministernotomy technique in HTAR was safe and technically feasible and may benefit individual patients as well as hospitals in general.

Exploration of thoracoabdominal aortic mixed reality optimisation and its clinical application value in type A aortic dissection

OBJECTIVES

This study aimed to explore the feasibility of low-dose computed tomography (CT)-based mixed reality and its clinical role in type A aortic dissection (TAAD) operations.

METHODS

Eighty-seven patients diagnosed with TAAD were prospectively enrolled and underwent thoracoabdominal aorta mixed reality. They were randomly divided into a low-dose mixed reality group, a conventional mixed reality group and a conventional thoracoabdominal aorta computed tomography angiography (CTA) group. Three-dimensional modelling, mixed reality and CT reconstruction technology were selected. The radiation dose and image quality were compared using Student's t test. Doctors with different seniorities evaluated the clinical application value of thoracoabdominal aorta mixed reality using a Likert scale. The consistency was assessed using the Cohen kappa coefficient (k). The Pearson chi-square test was used to test the correlation of perioperative index results in TAAD operations.

RESULTS

Low-dose CT technology can be effectively applied to thoracoabdominal aorta mixed reality and reduces the radiation dose by approximately 59% and the operation time and auxiliary cardiopulmonary bypass time by approximately 22% and 29%, respectively. The subjective scores of doctors with different seniorities on the clinical application value of thoracoabdominal aorta mixed reality were higher than those of thoracoabdominal aorta CTA (all p > 0.05).

CONCLUSIONS

Low-dose CT can be effectively used in thoracoabdominal aortic mixed reality to reduce the radiation dose while ensuring quality. Low-dose thoracoabdominal aortic mixed reality has clinical application value and can effectively reduce the operation time and auxiliary cardiopulmonary bypass time in TAAD operations.

KEY POINTS

• Low-dose CT technology can ensure the mixed reality quality of the thoracoabdominal aorta with a radiation dose reduction of approximately 59%. • Compared with thoracoabdominal aorta CTA, low-dose thoracoabdominal aorta mixed reality can reduce the operation time and auxiliary cardiopulmonary bypass time by approximately 20% and 29%, respectively, in TAAD operations. • The application value of low-dose thoracoabdominal aorta mixed reality in operation scheme formulation, operation risk assessment, operation navigation and diagnosis and treatment under safe distance was greater than that of thoracoabdominal aorta CTA in TAAD.

Aortic dissection with epileptic seizure: A case report

BACKGROUND

Aortic dissection (AoD) is a life-threatening disease. Its diversified clinical manifestations, especially the atypical ones, make it difficult to diagnose. The epileptic seizure is a neurological problem caused by various kinds of diseases, but AoD with epileptic seizure as the first symptom is rare.

CASE SUMMARY

A 53-year-old male patient suffered from loss of consciousness for 1 h and tonic-clonic convulsion for 2 min. The patient performed persistent hypomania and chest discomfort for 30 min after admission. He had a history of hypertension without regular antihypertensive drugs, and the results of his bilateral blood pressure varied greatly. Then the electroencephalogram showed the existence of epileptic waves. The thoracic aorta computed tomography angiography showed the appearance of AoD, and it originated at the lower part of the ascending aorta. Finally, the diagnosis was AoD (DeBakey, type I), acute aortic syndrome, hypertension (Grade 3), and secondary epileptic seizure. He was given symptomatic treatment to relieve symptoms and prevent complications. Thereafter, the medical therapy was effective but he refused our surgical advice.

CONCLUSION

The AoD symptoms are varied. When diagnosing the epileptic seizure etiologically, AoD is important to consider by clinical and imaging examinations.

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.

The great vessel freeze-out: A meta-analysis of conventional versus frozen elephant trunks in aortic arch surgery

Background

The optimal treatment strategy for complex aortic arch and proximal descending aortic pathologies remains controversial. Despite the frozen elephant trunk (FET) technique's increasing popularity, its use over the conventional elephant trunk (CET) remains a matter of physician preference and outcomes are varied.

Methods

This meta‐analysis of available comparative studies of FET versus CET sought to examine differences in survival, reintervention, and adverse events. The following databases were searched from inception—May 2020: Ovid MEDLINE, Ovid EMBASE, and The Cochrane Library. Studies retrieved were then screened for eligibility against predefined inclusion/exclusion criteria with a protocol registered on Open Science Framework at https://osf.io/hrfze/.

Results

The search identified 1911 citations, with five studies included. The resultant meta‐analysis included 313 CET and 292 FET cases. FET had lower perioperative mortality (risk ratio [RR]: 0.50, 95% confidence interval [CI]: [0.42; 0.60], p < .001) and improved 1‐year survival compared to CET (hazard ratio: 0.63, 95% CI: [0.42; 0.95], p = .03). There were no significant differences in rates of overall or open reinterventions following FET versus CET, but FET did yield a significantly higher rate of endovascular reintervention (RR: 2.32, 95% CI: [1.17; 4.61], p = .03). No significant differences were observed in the incidences of postoperative stroke, spinal cord injury, or renal failure between groups.

Conclusions

The FET technique yields superior rates of perioperative and medium‐term survival with no significant increase in overall reinterventions. There was no significant difference in the rate of spinal cord injury between groups, providing further large‐scale evidence that the FET is an acceptable, safe alternative to the CET.

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

Background

The 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.

Aims

The 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.

Methods

We 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.

Results

Thoraflex™ 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.

Conclusion

The 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.

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.

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.

Frozen elephant trunk in total arch replacement: A systematic review and meta-analysis of outcomes and aortic proximalization

BACKGROUND AND AIM OF THE STUDY

The frozen elephant trunk (FET) procedure became a popular entity for utilization in aortic arch aneurysm disease. However, its proper mortality and morbidities as well as the predictors of outcomes are poorly identified. This systematic review and meta-analysis explore FET outcomes and its predictors with a focus on zone aortic proximalization.

METHODS

We searched PubMed/MEDLINE, EMBASE, and Scopus databases from their beginning to June 2020 to find studies reporting the outcomes of the FET procedure for the total arch replacement (TAR).

RESULTS

A total of 64 studies including 7967 patients were evaluated. The pooled estimates of cerebrovascular accidents, paraplegia, renal failure, and in-hospital mortality were 7.104 (95% confidence interval [CI], 5.691-8.661; I²  = 78.53%), 3.465 (95% CI, 2.852-4.136; I²  = 15.96), 14.969 (95% CI, 11.361-18.977; I²  = 91.26%), and 8.933 (95% CI, 7.128-10.919; I²  = 78.51%), respectively. Stratification by the geographical locations and by the aortic pathologies led to lower heterogeneity, but not for renal failure. The distal anastomosis in Zone 2 was associated with a lower rate of renal failure compared with Zone 3 (odds ratio, 0.54; 95% CI, 0.36-0.81; p = .003; I²  = 0%).

CONCLUSIONS

The FET procedure for TAR can be performed with acceptable mortality and morbidities among patients with complex aortic pathologies. Moreover, the distal anastomosis in Zone 2 was associated with lower renal failure compared to Zone 3.