Simplified total arch repair with a stented graft for acute DeBakey type I dissection

Computed Tomography Imaging Measurements as a Surrogate for Clinical Outcomes After Surgical Management of Acute Type A Aortic Dissection: A Systematic Review

BACKGROUND

Postoperative computed tomography imaging surveillance is an essential component of care after acute type A aortic dissection (ATAAD) repair. Prognostic imaging factors after ATAAD repair have not been systematically reviewed.

METHODS AND RESULTS

We performed a systematic review to summarize postoperative computed tomography measurements including aortic diameter, cross-sectional area, volume, growth rate, and false lumen thrombosis in addition mid- to long-term clinical outcomes after ATAAD repair. Searches were conducted in Medline, Embase, and CENTRAL in October 2022. Studies were included if they reported clinical outcomes such as mortality or aortic reintervention after 1 year and included aforementioned computed tomography findings. Studies of chronic aortic dissection and studies of exclusive patient populations such as those with connective tissue diseases were excluded. Risk of bias was assessed with the Newcastle-Ottawa Scale. Searches retrieved 6999 articles. Sixty-eight studies met inclusion criteria (7885 patients). Extended repairs were associated with improved false lumen thrombosis, decreased aortic growth rate, and decreased rates of reintervention but not improved survival. Growth rates of the aorta post-ATAAD repair were highest in the descending thoracic aorta. The most frequent prognostic imaging factors reported were a patent/partially thrombosed false lumen and postoperative aortic diameter >40 to 45 mm.

CONCLUSIONS

Established measurements of positive aortic remodeling, including complete false lumen thrombosis and stabilization of postoperative aortic diameter and growth are the most studied prognostic indicators for improved clinical outcomes after ATAAD repair. Growth rate of the aorta remains significant after ATAAD repair. Future studies should prospectively evaluate and compare prognostic factors for improved surveillance and management.

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.

Hypothermic circulatory arrest time affects neurological outcomes of frozen elephant trunk for acute type A aortic dissection: A systematic review and meta-analysis

BACKGROUND

The treatment of complex thoracic aorta pathologies remains a challenge for cardiovascular surgeons. After introducing Frozen Elephant Trunk (FET), a significant evolution of surgical techniques has been achieved. The present meta-analysis aimed to assess the efficacy of FET in acute type A aortic dissection (ATAAD) and the effect of circulatory arrest time on post-operative neurologic outcomes.

METHODS

A standard Preferred Reporting Items for Systematic Reviews and Meta-Analyses search was conducted for all observational studies of patients diagnosed with ATAAD undergoing total arch replacement with FET reporting in-hospital mortality, bleeding, and neurological outcomes. A random-effect meta-analysis was performed using STATA software (StataCorp, TX, USA).

RESULTS

Thirty-five studies were eligible for the present meta-analysis, including 3211 patients with ATAAD who underwent total arch replacement with FET. The pooled estimate for in-hospital mortality, postoperative stroke, and spinal cord injury were 7% (95% CI 5 - 9; I²  = 68.65%), 5% (95% CI 4 - 7; I²  = 63.93%), and 3% (95% CI 2 - 4; I²  = 19.56%), respectively. Univariate meta-regression revealed that with increasing the duration of hypothermic circulatory arrest time, the effect sizes for postoperative stroke and SCI enhances.

CONCLUSIONS

It seems that employing the FET procedure for acute type A dissection is associated with acceptable neurologic outcomes and a similar mortality rate comparing with other aorta pathologies. Besides, increasing hypothermic circulation arrest time appears to be a significant predictor of adverse neurologic outcomes after FET.

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.

Hybrid two-stage repair of Stanford A dissection with visceral or peripheral malperfusion

Background

The present study aimed to evaluate the effect of two-stage hybrid aortic repair at the distal aorta of Stanford A dissection with malperfusion.

Methods

This retrospective case series included 20 patients with Stanford A dissection administered two-stage thoracic endovascular aortic repair (TEVAR) about 1 month after central repair because of visceral or limb malperfusion. The patients were examined by computed tomography (CT) angiography at 3, 6, 12 and 24 months after operation. Recovery of malperfusion and true lumen index were evaluated during follow-up.

Results

Twenty patients underwent two-stage hybrid aortic repair, including 11 males and 9 females. The follow-up time was 24 ± 7 months. No intervention-related complications were observed, including stent graft-induced new re-entry tears, death, stroke and spinal cord injury. Malperfusion in all cases was corrected. The true lumen was not enlarged enough 1 month after the first surgery. Thrombosis of the false lumen was observed around the elephant trunk at the carina level and the celiac artery. Three months after second stage TEVAR, the false lumen thrombosis was resorbed; in addition, the trunk was fully expanded at the carina level, and the true lumen was enlarged at the celiac artery.

Conclusions

Two-stage hybrid aortic repair for residual true lumen in the distal aorta 1 month after initial surgery is helpful for descending aorta remodeling and effective in treating malperfusion. This procedure may be a good option for patients suffering from Stanford A dissection with small true lumen in the distal aorta and malperfusion.

Long-term outcomes of the frozen elephant trunk procedure: a systematic review

Background

The frozen elephant trunk (FET) procedure remains an increasingly popular approach to address complex multi-segmental aortic pathologies, owing to their ability to promote false lumen thrombosis and reduce the need for second-stage operations. While the short-term outcomes of such procedures have been shown to be acceptable, much less is known regarding long-term outcomes. This systematic review evaluates long-term outcomes of the FET procedure.

Methods

Studies with at least 12 months follow-up data on FETs were identified in four electronic databases. All studies were reviewed by two independent researchers and relevant data extracted. Long-term outcomes, including overall survival, freedom from reintervention, and freedom from aortic events, were evaluated using patient data recreated from digitized Kaplan-Meier curves.

Results

Thirty-seven studies with 4,178 patients were identified. The majority of the studies focused solely on acute dissections. Average follow-up was 3.2 years. Overall survival at 1-, 3-, and 5-year was 89.6%, 85.2%, and 82.0%, respectively. Freedom from reintervention at the same timepoints were 93.9%, 89.3%, and 86.8%, respectively. Mortality, permanent neurological deficit and spinal cord injury were 10.2%, 7.7%, and 6.5%, respectively.

Conclusions

Survival after the FET procedure is favorable, though ongoing close serial monitoring is essential to assess for the need for further reintervention. Larger multi-institutional registries are required to provide more robust evidence to better elucidate the patient cohort that would most benefit from the FET.

Total arch repair with frozen elephant trunk using the “zone 0 arch repair” strategy for type A acute aortic dissection

OBJECTIVE

The aim of this study was to investigate the effect of frozen elephant trunk deployment from the zone 0 aorta to the descending aorta on early and midterm postoperative results in patients with acute type A aortic dissection.

METHODS

Between October 2014 and April 2018, 108 patients underwent a combined strategy of frozen elephant trunk deployment, ascending aortic replacement, and arch vessel reconstruction ("zone 0 arch repair" strategy) for acute type A aortic dissection (excluding DeBakey type II). Of the 108 patients, 32 (29.6%) had primary tears of the aortic arch or descending aorta.

RESULTS

The 30-day mortality rate was 2.8% (3 patients), and in-hospital mortality rate was 6.5% (7 patients). New-onset permanent neurologic dysfunction and spinal cord injury occurred in 3.7% and 0% of patients, respectively. Five of the 101 survivors underwent thoracic endovascular aortic repair during hospitalization (2 for rapid false lumen enlargement; 3 for true lumen stenosis). The overall survival was 89.8%, 88.1%, and 88.1% at 1, 2, and 3 years, respectively. The cumulative incidence of distal aortic reintervention was 5.8%, 9.1%, and 9.1% at 1, 2, and 3 years, respectively. Two patients underwent thoracic endovascular aortic repair for distal aortic enlargement after discharge.

CONCLUSIONS

The use of the "zone 0 arch repair" strategy can eliminate the need for invasive aortic arch resection. It also eliminates the false lumen and produces satisfactory early and midterm postoperative results. Therefore, it can be an alternative to hemiarch and total arch replacements, which are based on a conventional "tear-oriented resection" strategy.

Classification and outcomes of extended arch repair for acute Type A aortic dissection: a systematic review and meta-analysis

Objectives

Distal extent of repair in patients undergoing surgery for acute Type A aortic dissection (ATAAD) is controversial. Emerging hybrid techniques involving open and endovascular surgery have been reported in small numbers by select individual centres. A systematic review and meta-analysis was performed to investigate the outcomes following extended arch repair for ATAAD. A classification system is proposed of the different techniques to facilitate discussion and further investigation.

Methods

Using Ovid MEDLINE, 38 studies were identified reporting outcomes for 2140 patients. Studies were categorized into four groups on the basis of extent of surgical aortic resection and the method of descending thoracic aortic stent graft deployment; during circulatory arrest (frozen stented elephant trunk) or with normothermic perfusion and use of fluoroscopy (warm stent graft): (I) surgical total arch replacement, (II) total arch and frozen stented elephant trunk, (III) hemiarch and frozen stented elephant trunk and (IV) total arch and warm stent graft. Perioperative event rates were obtained for each of the four groups and the entire cohort using pooled summary estimates. Linearized rates of late mortality and reoperation were calculated.

Results

Overall pooled hospital mortality for extended arch techniques was 8.6% (95% CI 7.2-10.0). Pooled data categorized by surgical technique resulted in hospital mortality of 11.9% for total arch, 8.6% total arch and frozen stented elephant trunk, 6.3% hemiarch and frozen stented elephant trunk and 5.5% total arch and 'warm stent graft'. Overall incidence of stroke for the entire cohort was 5.7% (95% CI 3.6-8.2). Rate of spinal cord ischaemia was 2.0% (95% CI 1.2-3.0). Pooled linearized rate of late mortality was 1.66%/pt-yr (95% CI 1.34-2.07) with linearized rate of re-operation of 1.62%/pt-yr (95% CI 1.24-2.05).

Conclusions

Perioperative results of extended arch procedures are encouraging. Further follow-up is required to see if long-term complications are reduced with these emerging techniques. The proposed classification system will facilitate future comparison of short- and long-term results of different techniques of extended arch repair for ATAAD.

Descending endografts for type A dissections: con

An important goal of surgical repair of type A aortic dissection is to resect the intimal tear. Studies on the fate of residual dissection after acute type A aortic dissection repair in the past decade have driven surgeons to seek procedures to avoid distal reoperation. Aggressive surgical approach with total arch replacement in acute type A dissection has demonstrated lower incidence of distal reoperation and slower aortic growth rate compared to less aggressive ascending/hemiarch repair. Recently, successful results of thoracic endovascular aortic repair (TEVAR) in type B aortic dissection have encouraged surgeons to further attack acute type A aortic dissection with hybrid approach: antegrade endografting in the descending thoracic true lumen as an adjunct to hemiarch or total arch repair. However, is the hybrid approach with simultaneous descending endografting justified in all the acute type A aortic dissection cases? The outcomes of the hybrid approach reported by the several groups have demonstrated 80-100% of false lumen thrombus formation in the proximal descending aorta (stented segment); however, the complete obliteration of the false lumen is only 17-50%. The incidence of distal reoperation/reintervention after hybrid approach is as high as 14% and an adjunctive procedure is often performed. Moreover, there are concerns about additional risks associated with the hybrid procedures, such as spinal cord injury (SCI), stent graft induced new entry and stroke. The data on this new approach are still very limited. Hence, further study is warranted to prove its safety and durability.

A Meta-Analysis of Total Arch Replacement With Frozen Elephant Trunk in Acute Type A Aortic Dissection

Objectives:

To assess the safety and efficacy, we performed a meta-analysis of total arch replacement with frozen elephant trunk in exclusive acute type A (neither chronic nor type B) aortic dissection.

Methods:

Databases including MEDLINE and EMBASE were searched through March 2015 using Web-based search engines (PubMed and OVID). Eligible studies were case series of frozen elephant trunk enrolling patients with acute type A (neither chronic nor type B) aortic dissection reporting at least early (in-hospital or 30-day) all-cause mortality. Study-specific estimates were combined in both fixed- and random-effect models.

Results:

Fifteen studies enrolling 1279 patients were identified and included. Pooled analyses demonstrated the cardiopulmonary bypass time of 207.1 (95% confidence interval [CI], 186.1-228.1) minutes, aortic cross-clamp time of 123.3 (95% CI, 113.1-133.5) minutes, selective antegrade cerebral perfusion time of 49.3 (95% CI, 37.6-61.0) minutes, hypothermic circulatory arrest time of 39.0 (95% CI, 30.7-47.2) minutes, early mortality of 9.2% (95% CI, 7.7-11.0%), stroke of 4.8% (95% CI, 2.5-9.0%), spinal cord injury of 3.5% (95% CI, 1.9-6.6%), mid- to long-term (≥1-year) overall mortality of 13.0% (95% CI, 10.4-16.0%), reintervention of 9.6% (95% CI, 5.6-15.8%), and false lumen thrombosis of 96.8% (95% CI, 90.7-98.9%).

Conclusions:

Total arch replacement with frozen elephant trunk provides a safe alternative to that with conventional elephant trunk in patients with acute type A aortic dissection, with acceptable early mortality and morbidity. The rates of mid- to long-term reintervention and false lumen non-thrombosis may be lower in patients undergoing the frozen than conventional elephant trunk procedure.