Predictors of early and late outcome after total arch replacement for atherosclerotic aortic arch aneurysm

Aortic Arch Repair Using Open and Hybrid Techniques: A Systematic Review

Early surgical intervention is critical for treatment of aortic arch aneurysms and dissections, but limited comprehensive data exist to define the optimal approach for surgical management with respect to postoperative outcomes. We conducted a systematic review of the 2 most common surgical approaches-total arch replacement and hybrid arch repair. We referenced the electronic PubMed database reporting on outcomes for these surgical approaches from inception to June 2022. Our initial search query returned a total of 2,517 records. All records were independently screened for adherence to our inclusion criteria and a total of 12 retrospective cohort studies were identified as appropriate for inclusion. Across the included studies, a total of 618 patients underwent hybrid repair, as compared to 2,104 patients who underwent total arch replacement. We found that most of the literature supported the findings of similar rates of permanent neurologic dysfunction, acute kidney injury, and short-term mortality between approaches and higher postoperative reintervention rates following hybrid repair. Reported outcomes of studies included in this review often conflicted regarding midterm and long-term survival, as well as hospital and intensive care unit length of stay following open and hybrid repair. Future studies should address midterm and long-term survival with a prospective study design.

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.

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.

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.

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.

Long-term survival and related outcomes for hybrid versus traditional arch repair-a meta-analysis

Background

Surgical interventions for aortic aneurysm and dissection remain associated with high risk of mortality and morbidity. Advances in operative techniques have led to a variety of options for the cardiac surgeon, including endovascular and hybrid approaches. Debate remains over which of these techniques provide optimal outcomes for the patient. The present systematic review and meta-analysis aims to evaluate long term patient survival and identify short-term outcomes for conventional (open) aortic arch repair and hybrid aortic arch repair (HAR).

Methods

An electronic literature search was conducted according to predefined inclusion criteria for hybrid and conventional aortic arch repair surgery. Digitized survival data was extracted from identified studies' Kaplan-Meier curves and used to re-create individual patient data for aggregated survival analysis. Post-operative morbidity and mortality were analyzed using random-effects model meta-analysis.

Results

Nine studies were included, containing 841 hybrid arch repair and 1,182 conventional arch repair patients. Pooled Kaplan-Meier analysis of all patients demonstrated higher survival in hybrid arch repair patients than conventional arch repair patients, however, this was noted to be sensitive to results from a particular study. Overall results showed for the hybrid repair cohort, survival at 1, 2, 3, 5 and 7 years was 87%, 85%, 83%, 78% and 75%, respectively. Survival in the conventional repair cohort at 1, 2, 3, 5 and 7 years was 84%, 82%, 80%, 75% and 71%, respectively. Statistically significant findings from meta-analysis showed hybrid arch repair was associated with lower risk of re-operation for bleeding, while conventional arch repair was associated with reduced risk of spinal cord injury.

Conclusions

Pooled Kaplan-Meier analysis of all studies showed long-term survival outcomes for hybrid and conventional aortic arch repair patients are heterogeneous and sensitive to the results of particular studies. Superior results from particular centres and the low number of comparative studies mean that more data is required to make definitive findings with regards to the long-term survival outcomes of either procedure. Hybrid arch repair was associated with lower risk of re-operation for bleeding, while conventional arch repair was associated with lower risk of spinal cord injury. Surgeons should consider their own center's experience and patient suitability when deciding between hybrid or conventional aortic repair techniques.

A rat model of aortic arch aneurysm with excellent survival

BACKGROUND

The complex mechanisms of aortic arch aneurysm have not been well studied. An animal model of aortic arch aneurysm would be beneficial to study this fatal disease. In this study, we tried to establish a rat model of aortic arch aneurysm by constricting the aortic isthmus.

METHODS

Forty-eight male Sprague-Dawley rats were randomly divided into three groups. Rats with no aortic isthmus constriction were assigned to group A (control group). The aortic isthmus was constricted to 1.5 mm in group B and to 0.8 mm in group C. The blood pressure of the rats was measured at 0, 1, 3 and 6 months after the operation. The diameter and wall thickness of aortic arch were measured at 3 and 6 months after surgery.

RESULTS

Compared to group A, group B showed no significant increase in blood pressure or aortic diameter after the operation. Compared to the control group, group B showed a marked increase in wall thickness at 3 and 6 months after surgery (p < 0.05). Compared to group A, group C showed significant increases in both blood pressure (p < 0.05) and aortic diameter (p < 0.05) after the operation. Group C also showed a more than 50% increase in wall thickness at 3 and 6 months after surgery (P < 0.05).

CONCLUSIONS

By constricting the aortic isthmus to 0.8 mm, a rat model of aortic arch aneurysm could be induced at 3 and 6 months after surgery.