Long-term results of the frozen elephant trunk technique in primary chronic type B aortic dissection

OBJECTIVES

The aim of this study is to analyze long-term results of the total aortic arch replacement with the frozen elephant trunk technique for primary chronic type B aortic dissection.

METHODS

Among 322 patients who had the frozen elephant trunk technique, 43 (13.4%) patients (median age, 64.0 years) with primary chronic type B aortic dissection were analyzed. The patients underwent surgery at a median of 27.0 months after the onset of aortic dissection. The false lumen was patent in 30 (69.8%) patients preoperatively.

RESULTS

Two patients suffered paraplegia and another died of cerebral infarction. Complete thrombosis of the peri-stent false lumen was achieved in 36 (83.7%) patients. Overall survival, freedom from aortic events, and freedom from aortic reintervention were 83.5%, 37.2%, and 42.2% at 5 years, respectively. Survival rates of the patients with or without aortic events were 75.0% and 95.8% at 5 years (Log-rank, p = 0.22). Late aortic events occurred in 19 (44.2%) patients including distal stent graft-induced new entry, type Ib endoleak, and false lumen dilation. The ratio of the stent graft diameter to the preoperative short axis diameter of the true lumen (hazard ratio, 1.90; 95% confidence interval, 1.01-3.59), and the maximal diameter of a postdissection aneurysm (1.07; 1.01-1.12) were the significant multivariate risk predictors of late aortic events.

CONCLUSIONS

Late aortic events occurr fairly frequently, and new strategies need to be explored to enhance the effectiveness of this procedure in the future.

Surgical treatment in the chronic phase for uncomplicated Stanford type B aortic dissection

BACKGROUND

The most appropriate surgical method for patients with uncomplicated type B aortic dissection (UTBAD) in the chronic phase remains controversial. This study evaluated the outcomes of patients with UTBAD who needed aortic treatment as well as the impact of the treatment method or indication criteria on their prognosis.

METHODS

This retrospective review of 106 consecutive patients with aortic events in the chronic phase who underwent initial treatment for UTBAD between 2004 and 2021 comprised three groups: 19 patients who underwent endovascular repair (TEVAR), 38 who underwent open aortic repair and the medication group that included 49 patients. Aortic events were defined as a late operation or indication for operation for dissected aorta, aortic diameter (AD) ≥ 55 mm, rapid aortic enlargement (≥5 mm/6 months), and saccular aneurysmal change. The endpoint was all-cause death. We assessed the association between treatment methods or surgical indication criteria and mortality using a Cox regression analysis.

RESULTS

The 5-year actuarial mortality rates were 27.1% in the TEVAR group, 19.6% in the open aortic repair group, and 38.4% in the medication group (p = 0.86). Moreover, the 5-year actuarial mortality rates in patients who had AD ≥ 55 mm were significantly higher than those patients with other surgical indication criteria (41.2% vs. 18.7%, p < 0.01). Multivariable analysis revealed a significant difference in AD ≥ 55 mm (hazard ratio [HR]: 2.88, 95% confidence interval [CI] 1.38-6.02, p < 0.01) and age (HR: 1.09, 95% CI 1.05-1.13, p < 0.01).

CONCLUSIONS

Under the existing surgical indication criteria, there was no difference in mortality rates among patients with UTBAD based on their surgical treatment.

[Postoperative sternomediastinitis: morphology of lesion, treatment strategy]

OBJECTIVE

To analyze bone tissue damage at different stages of disease (El Oakley classification), treatment options for each clinical situation and results after each approach.

MATERIAL AND METHODS

There were 45 patients with wound complications after cardiac surgery between October 2022 and September 2023. Thirty-eight (84.4%) patients underwent CABG, 7 (15.6%) patients - heart valve or aortic surgery. Mean age of patients was 68.1±10.3 years. There were 35 men (77.8%) and 10 women (22.2%). The first type was found in 11 (24.5%) patients, type 2-3 - 19 (42.2%), type 4 - 4 (8.8%), type 5 - 11 (24.5%) patients.

RESULTS

Systemic inflammatory response syndrome was observed in 7 (36.8%) persons of the 1st group, 14 (73.7%) ones of the 2nd group, 4 (100%) patients of the 3rd group and 2 (18.2%) patients of the 4th group. C-reactive protein and procalcitonin increased in all patients with the highest values in groups 2 and 3. Redo soft tissue inflammation occurred in all groups after treatment. Mean incidence was 25%. Two (10.5%) patients died in the 2nd group and 1 (25%) patient in the 3rd group.

CONCLUSION

The modern classification of sternomediastinitis does not fully characterize severity of disease in a particular patient. Simultaneous debridement with wound closure demonstrates acceptable mortality (within 10%). The highest mortality rate was observed in patients with diffuse lesions of the sternum. Less aggressive treatment approaches are possible for stable anterior chest wall.

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.

Hybrid Treatment of Complex Diseases of the Aortic Arch and Descending Thoracic Aorta by Frozen Elephant Trunk Technique

The surgical management of acute and chronic complex diseases involving the aortic arch and the descending thoracic aorta remains challenging. Hybrid procedures associating total open arch replacement and stent-grafting of the proximal descending aorta were developed to allow a potential single-stage treatment, promote remodeling of the downstream aorta, and facilitate a potential second-stage thoracic endovascular aortic repair by providing an ideal landing zone. While these approaches initially used various homemade combinations of available conventional prostheses and stent-grafts, the so-called frozen elephant trunk technique emerged with the development of several custom-made hybrid prostheses. The aim of this study was to review the contemporary outcomes of this technique in the management of complex aortic diseases, with a special focus on procedural planning, organ protection and monitoring, refinements in surgical techniques, and long-term follow-up.

Frozen Elephant Trunk for Aortic Dissection Using Different Hybrid Grafts: Preliminary Results from a Prospective Study

BACKGROUND

The frozen elephant trunk technique has become popular and led to an expansion of indications for surgery. Various hybrid grafts for the frozen elephant trunk are used, sometimes with significantly different features. The objective of this study was to compare early- and mid-term outcomes after the frozen elephant trunk for aortic dissection using different hybrid grafts.

METHODS

The prospective study included 45 patients with acute/chronic aortic dissections. The patients were randomized into two groups. Group 1 patients (n = 19) were implanted with a hybrid graft E-vita open plus (E-vita OP). Group 2 (n = 26) included patients who received a MedEng graft. The inclusion criteria were type A and type B acute and chronic aortic dissection. The exclusion criteria were as follows: hyperacute aortic dissection (less than 24 h), organ malperfusion, oncology, severe heart failure, stroke, and acute myocardial infarction. The primary endpoint was early- and mid-term mortality. The secondary endpoints were postoperative complications (stroke and spinal cord ischemia, myocardial infarction, respiratory failure, acute renal injury, and re-operation for bleeding).

RESULTS

The rate of stroke and spinal cord ischemia in the E-vita OP vs. MedEng groups was 11% vs. 4% (p = 0.565) and 11% vs. 0% (p = 0.173), respectively. The respiratory failure rate was comparable in both groups (p > 0.999). Acute kidney injury requiring hemodialysis and the need for re-sternotomy in the MedEng group vs. E-vita OP group was 31% vs. 16% (p = 0.309) and 15% vs. none (p = 0.126), respectively. Early mortality in the MedEng and E-vita OP groups did not differ (8% vs. 0, p = 0.501). The mid-term survival in the analyzed groups was 79% vs. 61%, (p = 0.079), respectively.

CONCLUSIONS

No statistically significant differences were observed between patients receiving frozen elephant trunk with the hybrid MedEng and E-vita OP grafts in regard to early mortality and morbidity. Mid-term survival was also non-significant between analyzed groups with a trend toward more favorable mortality in the MedEng group.

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.

A new dissection-specific hybrid stent graft for patients with DeBakey type I aortic dissection

OBJECTIVES

We present our first experience of using a new dissection-specific hybrid stent graft (SG) (the 'Soft Elephant Trunk') in the frozen elephant trunk technique, in patients with non-acute DeBakey type I aortic dissection.

METHODS

Between September 2016 and February 2021, patients with non-acute DeBakey type I aortic dissection underwent the frozen elephant trunk procedure at our centre using 3 SG types: group Z used stiff, distal Z-shaped nitinol SGs (E-Vita, Medtronic); group R used a stiff, ring-shaped nitinol SG (Thoraflex); and group S used a soft, distal dissection-specific SG. Predictors of distal SG-induced new entry were analysed. End points were hospital- and midterm-follow-up results.

RESULTS

The study comprised 109 patients with 46 (42.2%), 22 (20.2%) and 41 (37.6%) patients in groups Z, R and S, respectively. No significant differences were found in early outcomes. Freedom from distal SG-induced new entry was comparable in groups Z, R and S (68.9% vs 92.9% vs 100%, log-rank = 0.14). There was no significant difference in follow-up between the groups. Four-year survival rates were 80.44%, 71.59% and 95.06% in groups Z, R and S, respectively. On multivariable analysis, the presence of connective tissue disorders [hazard ratio (HR) = 5.62, P = 0.11] and SG diameter (HR = 1.37, P = 0.034) were strong predictors of distal SG-induced new entry.

CONCLUSIONS

Dissection-specific hybrid SG with a soft distal end is effective in patients with non-acute DeBakey type I aortic dissection. Compared to non-soft distal SGs, this can reduce the incidence of distal complications. Long-term outcomes are necessary to determine the potential advantages and disadvantages of the new prosthesis.

Early and Long-Term Follow-Up for Chronic Type B and Type Non-A Non-B Aortic Dissection Using the Frozen Elephant Trunk Technique

Background: This study aimed to evaluate the early and long-term outcomes of a single center using a frozen elephant trunk (FET) procedure for chronic type B or non-A non-B aortic dissection.

Methods: From February 2009 to December 2019, 79 patients diagnosed with chronic type B or non-A non-B aortic dissection who underwent the FET procedure were included in the present study. We analyzed operation mortality and early and long-term outcomes, including complications, survival and interventions.

Results: The operation mortality rate was 5.1% (4/79). Spinal cord injury occurred in 3.8% (3/79), stroke in 2.5% (2/79), and acute renal failure in 5.1% (4/79). The median follow-up time was 53 months. The overall survival rates were 96.2, 92.3, 88.0, 79.8, and 76.2% at 1/2, 1, 3, 5 and 7 years, respectively. Moreover, 79.3% of patients did not require distal aortic reintervention at 7 years. The overall survival in the subacute group was superior to that in the chronic group (P = 0.047).

Conclusion: The FET technique is a safe and feasible approach for treating chronic type B and non-A non-B aortic dissection in patients who have contraindications for primary endovascular aortic repair. The technique combines the advantages of both open surgical repair and endovascular intervention, providing comparable early and long-term follow-up outcomes and freedom from reintervention.

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.

Intraoperative angiography for visceral arteries originating from false lumen

A 70-year-old man had an acute type B aortic dissection 9 years before his admission. The last enhanced computed tomography that was performed revealed an aneurysm that extended from the ascending aorta to the aortic arch, associated with a chronic aortic dissection, which extended from the aortic arch to the left external iliac artery. His visceral arteries originated from the false lumen. We performed a total arch replacement with a frozen elephant trunk in the hybrid operating room. Immediately after the circulatory arrest termination, using intraoperative angiography, we verified that the blood supply to the visceral arteries was patent.

"Proximalization is Advancement"-Zone 3 Frozen Elephant Trunk vs Zone 2 Frozen Elephant Trunk: A Literature Review

Over the decades, the Frozen Elephant Trunk (FET) technique has gained immense popularity allowing simplified treatment of complex aortic pathologies. FET is frequently used to treat aortic conditions involving the distal aortic arch and the proximal descending aorta in a single stage. Surgical preference has recently changed from FET procedures being performed at Zone 3 to Zone 2. There are several advantages of Zone 2 FET over Zone 3 FET including reduction in spinal cord injury, visceral ischemia, neurological and cardiovascular sequelae. In addition, Zone 2 FET is a technically less complicated procedure. Literature on the comparison between Zone 3 and Zone 2 FET is scarce and primarily observational and anecdotal. Therefore, further research is warranted in this paradigm to substantiate current surgical treatment options for complex aortic pathologies. In this review, we explore literature surrounding FET and the reasons for the shift in surgical preference from Zone 3 to Zone 2.

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.

The Frozen Elephant Trunk Technique for the Treatment of Type B and Type Non-A Non-B Aortic Dissection

OBJECTIVE

To evaluate outcomes of patients with acute complicated or chronic Type B or non-A non-B aortic dissection who underwent the frozen elephant trunk (FET) technique.

METHODS

Between April 2013 and July 2019, 41 patients presenting with acute complicated (n = 29) or chronic (n = 12) descending thoracic aortic dissection were treated by the FET technique, which was the treatment of choice when supra-aortic vessel transposition would not suffice to create a satisfactory proximal landing zone for endovascular aortic repair, when a concomitant ascending or arch aneurysm was present, or in patients with connective tissue diseases.

RESULTS

One patient (2%) died intra-operatively secondary to an aortic rupture in dwnstream aortic segments. No post-operative deaths occurred. Four patients (10%) suffered a non-disabling posto-operative stroke and were discharged with no clinical symptoms (modified Rankin Scale [mRS] 0, n = 1), no significant disability (mRS 1, n = 2), or with slight disability (mRS 2, n = 1). No spinal cord ischaemia was observed. The primary entry tear was either surgically resected or excluded from circulation in all patients. During follow up, one patient (2%) died after two years (not aorta related) and 16 patients (39%) underwent an aortic re-intervention after 7.7 [interquartile range 0.7, 15.8] months (endovascular aortic repair: n = 14; open thoraco-abdominal aortic replacement: n = 1, hybrid approach: n = 1).

CONCLUSION

The FET technique is an effective treatment option for acute complicated and chronic Type B or non-A non-B aortic dissection in patients in whom primary endovascular aortic repair is non-feasible. While the post-operative outcome is acceptable with a relatively low incidence of non-disabling strokes, this study also underlines the considerable need for aortic re-interventions. Continuous follow up of all patients undergoing the FET procedure is essential.

Techniques and outcomes of total aortic arch repair with frozen elephant trunk for DeBakey I dissections

Total aortic arch replacement (TAR) with frozen elephant trunk (FET) technique (FET) has been increasingly used to treat a variety of aortic pathologies over the past two decades. Because FET can effectively treat the diseased arch and cover the proximal entry tear in the distal arch, it is a valuable option in the treatment of DeBakey I aortic dissections. This report focuses on the techniques and outcomes of TAR with FET for acute/chronic aortic dissection. A review of pooled literature including 27 observational studies showed in-hospital mortality, permanent stroke, and spinal cord injury rates of 8.4%, 5.9% and 2.6% for acute aortic dissections, and 7.5%, 4.0% and 4.6% for chronic aortic dissections, respectively. In most of the studies, complete false lumen thrombosis rate was achieved in 80% of patients at the level of FET for acute and chronic aortic dissections. Mid-term outcomes are equally promising. For chronic aortic dissections, positive remodeling of the non-stented distal aortic segments is less frequent leading to secondary reinterventions within 3 to 5 years. However, most studies have not applied distal abdominal extensions of the repair using fenestrated and branched endografts. In the current endovascular era, TAR + FET should be considered as an alternative to conventional open surgical repair in centers of excellence.