Endovascular repair of residual intimal tear or distal new entry after frozen elephant trunk for type A aortic dissection

Hemodynamic predictors of negative false lumen remodeling after frozen elephant trunk for acute aortic dissection

OBJECTIVE

We evaluated the blood flow within the downstream aortic false lumen after frozen elephant trunk repair for acute aortic dissection and identified hemodynamic predictors of false lumen expansion and negative false lumen remodeling using four-dimensional flow magnetic resonance imaging.

METHODS

Thirty-one patients (Stanford type A, n = 28; Stanford type B, n = 3) with patent false lumen who underwent frozen elephant trunk procedures for acute aortic dissection were included in this observational study. Each patient underwent computed tomography during the follow-up period and four-dimensional flow magnetic resonance imaging within 3 postoperative months. The false lumen volumetric expansion rate was calculated using computed tomography data. The direction and the rate of flow in the lower descending aortic false lumen were analyzed. Negative false lumen remodeling was defined as a volumetric increase of > 10% from the baseline volume.

RESULTS

Negative false lumen remodeling had developed in 6 of the 31 patients during the observation period. Most of the false lumen flows were biphasic during systole. The range between peak and nadir flow rates was associated with the false lumen volumetric expansion rate (β coefficient = 6.77; p < 0.01, R2 = 0.43).

CONCLUSIONS

The range between peak and nadir flow rates may serve as a hemodynamic predictor of negative false lumen remodeling, enabling further treatment for patients at risk of expansion in the downstream aorta.

Complementary Thoracic Endovascular Aortic Repair (TEVAR) after Frozen Elephant Trunk for Residual Type A Aortic Dissection: Perioperative and Mid-Term Outcomes

Objectives: The aim of this retrospective study was to evaluate the results of complementary TEVAR following the frozen elephant trunk (FET) procedure for patients with residual type A aortic dissection (rTAAD) in terms of technical feasibility, safety and mid-term outcomes. Methods: This was a retrospective single-centre analysis of patients who received TEVAR after FET for rTAAD from January 2012 up to December 2021. The primary endpoint was technical success. Safety parameters included 30-day/in-hospital morbidity and mortality. Furthermore, mid-term clinical and morphological outcomes were evaluated. Results: Among 587 TEVAR procedures, 60 patients (11 with connective tissue disorders) who received TEVAR after FET for rTAAD were identified. The median interval between FET and TEVAR was 28.5 months. Indications for TEVAR after FET were true lumen collapse distal to FET prosthesis (n = 7), dSINE (n = 2), planned completion (n = 13) and aortic diameter progression (n = 38). In forty-seven patients, TEVAR was performed in an elective setting; eight and six patients were operated on in an urgent or emergency setting, respectively. All TEVAR procedures were successfully completed. The 30-day mortality and spinal cord ischemia rates were 1.7%. During a median follow-up of 37 months, two further patients died. Nine patients had to undergo a further aortic intervention: fenestrated stent-graft (n = 3) or open repair of the infrarenal abdominal aorta (n = 6). Conclusions: Complementary TEVAR following FET for rTAAD showed excellent technical success and low perioperative risk, supporting the feasibility and safety of this strategy. Despite the favourable mid-term survival, certain patients might require a further aortic procedure.

Outcomes of fenestrated endovascular abdominal aortic repair in distal entry tears of chronic debakey IIIb aortic dissection

Currently, there have been very few reports within the literature which specifically address using fenestrated and branched stent grafts to completely isolate and repair distal entry tears of chronic DeBakey IIIb aortic dissection. This study aimed to evaluate the clinical outcomes of a 3-dimensional (3D) printed aortic model-guided fenestrated stent in the treatment of distal tears of chronic DeBakey IIIb aortic dissection after thoracic endovascular aortic repair (TEVAR). The study was a one-center retrospective study comprising 36 patients who underwent TEVAR and fenestrated endovascular abdominal aortic repair (F-EVAR) between April 2014 and December 2022. Patient data was compiled and analysed for preoperative, intraoperative, and perioperative characteristics. In total, 36 patients (12 females and 24 males) were incorporated into this study. All of the patients included in this study had hypertension, and among them, the leading cause for undergoing II-stage F-EVAR was the progression of a false lumen, accounting for 24 cases (66.7% of the total). The technical success rate was 97.2% and there were no cases of 30-day mortality, myocardial infarction, permanent paraparesis, or organ failure. One year post-F-EVAR treatment, surviving patients showed significant false and true lumen remodelling with 100% complete false-lumen thrombosis. A total of five patients died during the follow-up, two patients died related to aorta complications and three patients died of heart failure, multiple organ failure, or septic shock. II-stage F-EVAR was safe and feasible operation to repair all distal tears of chronic DeBakey IIIb aortic dissection.

Early endovascular intervention for unfavorable remodeling of the thoracic aorta after open surgery for acute DeBakey type I aortic dissection: study protocol for a multicenter, randomized, controlled trial

BACKGROUND

Total arch replacement with frozen elephant trunk has been developed with promising results for DeBakey type I aortic dissection. However, several problems, such as continuous perfusion of distal false lumen and unfavorable remodeling of distal aorta postoperatively, can seriously affect the long-term outcome. This trial aims to assess the effects of early minimally invasive endovascular repair on distal aortic remodeling and long-term clinical outcomes in patients with dominant false lumen and residual tears in the descending thoracic aorta after total arch replacement and frozen elephant trunk procedure.

METHODS

This is a protocol for a two-arm, parallel, multicenter, randomized controlled trial. A total of 154 eligible patients will be recruited from four hospitals in China and randomized on a 1:1 basis either to the experiment group (endovascular repair in addition to routine antihypertensive therapy) or the control group (routine antihypertensive therapy without early surgical treatment). The primary outcome will be the five-year all-cause mortality. The secondary outcomes will include re-intervention, ischemic symptoms, organ dysfunction, and stent-related adverse events.

DISCUSSION

If early minimally invasive endovascular repair could safely and effectively promote distal aortic remodeling and bring favorable long-term outcomes for patients with dominant false lumen and residual tears in the descending thoracic aorta after total arch replacement and frozen elephant trunk technique, it would improve the treatment strategy for DeBakey type I aortic dissection.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, CHiCTR2000030050. Registered on 11 March 2020.

Outcomes of Secondary Endovascular Aortic Repair After Frozen Elephant Trunk

OBJECTIVE

The aim of this study was to evaluate the midterm outcomes of secondary extension of frozen elephant trunk (FET) by means of thoracic endovascular aortic repair (TEVAR).

METHODS

This single-center prospective study was conducted in a tertiary aortic center on consecutive patients having undergone TEVAR with an endograft covering most of the 10 cm FET module with 2 to 4 mm oversizing. All patients were monitored by computerized tomography angiography (CTA) at sixth month and yearly thereafter.

RESULTS

From January 2015 to July 2022, among 159 patients who received FET, 30 patients (18.8%) underwent a TEVAR procedure (13 for a thoracoabdominal aneurysm, 11 for a chronic aortic dissection and 6 for an emergency procedure). All connections were successfully achieved with 2 postoperative deaths (6.6%) and 1 paraplegia (3.3%). At a median follow-up of 21 months (interquartile range [IQR], 4.2-34.7), 5 patients (25%) required a fenestrated-branched endovascular aortic repair (F-BEVAR) extension followed by 4 patients with 5 reinterventions, 3 for a Type 3 endoleak due to disconnection between FET and TEVAR endograft, and 2 unrelated to the FET for a secondary Type 1C endoleak. All reinterventions were successful, without mortality or morbidity.

CONCLUSIONS

In this series, FET connection with a TEVAR endograft was effective with low postoperative morbidity but with a risk of aortic reintervention related to disconnection between the FET and TEVAR endograft. These results suggest the need for annual CTA monitoring with no time limit in patients following connection of the FET with a TEVAR endograft.

CLINICAL IMPACT

In this series of 30 patients, midterm outcomes of secondary extension of frozen elephant trunk (FET) by thoracic endovascular repair (TEVAR) showed 3 disconnections (10%) with a Type 3 endoleak between FET and TEVAR. These findings suggest the need for annual CTA monitoring with no time limit. But so far, only a few studies provide some information after one year while the risk of disconnection increases over time and becomes a concern after 3 years. This is the new message brought by our study.

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.

Endovascular reintervention after frozen elephant trunk: where is the evidence?

The introduction of the single-step hybrid frozen elephant trunk (FET) procedure for total arch replacement has revolutionized the field of aortovascular surgery. FET has proven to achieve excellent results in the repair of complex thoracic aorta pathologies. However, there remains a risk of reintervention post-FET for a variety of causes. This secondary intervention can either be performed endovascular, with thoracic endovascular aortic repair (TEVAR), or via open surgery. Multiple FET hybrid prosthesis are commercially available, each requiring different rates of endovascular reintervention. The current review will focus on providing an overview of the reintervention rates for main causes in relation to the FET grafts on the market. In addition, strategies to prevent reintervention will be highlighted. A comprehensive literature search was conducted on multiple electronic databases including PubMed, Ovid, Scopus and Embase to highlight the evidence in the literature on endovascular reintervention after FET. The main causes for secondary intervention are distal stent graft-induced new entry (dSINE), endoleak and negative aortic remodeling, and to a much lesser extent, graft kinking and aorto-esophageal fistulae. In addition, it is clear that the Thoraflex Hybrid (Terumo Aortic, Inchinnan, UK) is the superior FET device, showing excellent reintervention rates for all the above causes. Interestingly, the choice of FET device as well as its size and length can help prevent the need for reintervention. The FET procedure is indeed associated with excellent clinical outcomes, however, the need for reintervention may still arise. Importantly, the Thoraflex Hybrid prosthesis has shown excellent results when it comes to endovascular reintervention. Finally, several strategies exist that can prevent reintervention.

Downstream thoracic endovascular aortic repair following the frozen elephant trunk procedure

The frozen elephant trunk technique has become a well-established treatment option for patients presenting all thoracic aortic pathologies including acute and chronic dissection, aortic aneurysms and even penetrating aortic ulcers involving the aortic arch and descending aorta. Nevertheless, there is a significant incidence of and risk for distal aortic reinterventions after the frozen elephant trunk. Indications mainly include a planned staged approach, diameter progression of downstream aortic segments and the development of distal stent-graft induced new entries (dSINEs). Endovascular stent-graft extension through conventional thoracic endovascular aortic repair (TEVAR) is a relatively simple and safe method to address any pathologies in the remaining descending thoracic aorta up to the level of the coeliac trunk. In fact, the frozen elephant trunk stent-graft provides an ideal proximal landing zone for any endovascular stent-graft extension. Postoperative outcomes are very promising with very low reported in-hospital mortality and morbidity. In case this 2-staged-approach fails to stabilize the remaining aorta, a 3-step procedure, namely open thoracoabdominal aortic replacement, is simplified because the anastomosis site has moved distally. Follow-up of all patients, following frozen elephant trunk implantation or distal stent-graft extension, is mandatory, ideally in an outpatient clinic dedicated to the aorta in order to identify disease progression or to detect any complications as soon as possible.

Open or endovascular treatment of downstream thoracic or thoraco-abdominal aortic pathology after frozen elephant trunk: perioperative and mid-term outcomes

OBJECTIVES

The aim of this study was to evaluate the outcomes of open and endovascular treatment of downstream thoracic or thoraco-abdominal aortic pathology in patients who underwent previous frozen elephant trunk (FET).

METHODS

Data were retrieved to evaluate mortality, cardiac, pulmonary, cerebrovascular, renal and spinal cord major adverse events, early- and mid-term reintervention and survival rates. The Society for Vascular Surgery endovascular reporting standards were used.

RESULTS

From 2011 to 2020, 48 patients (36 males, median age 60 years) underwent downstream aortic repair at a median of 18 months (interquartile range: 6-57) after the initial FET. Twenty-eight patients (58.3%) received open and 20 (41.7%) endovascular repair. The overall 30-day mortality was 6.3% and the initial clinical success was 88%, with no inter-group differences (P = 0.22 and 0.66 respectively). Six spinal cord deficits were recorded (13%): 3 (6.3%) were permanent. The major adverse events incidence was lower in the endovascular cohort [4 (20%) vs 14 (50%); P = 0.047], mainly due to a lower rate of grade ≥2 respiratory complications (5% vs 42.9%; P = 0.004). Assisted primary clinical success at 5 years was higher in the endovascular group (95% vs 68%, P = 0.022); freedom from reintervention at competing risk analysis (P = 0.3) and overall survival at Kaplan-Meier curves (log-rank P = 0.29) were similar.

CONCLUSIONS

Downstream aortic repair after FET is feasible with both open and endovascular repair with acceptable mortality and permanent paraplegia rates. The endovascular approach has potential perioperative and mid-term advantages, but long-term durability has to be further investigated in larger cohorts.

TEVAR Following FET: Current Outcomes of Rendezvous Procedures in Clinical Practice

BACKGROUND

 The treatment of extensive thoracic/thoracoabdominal aortic pathologies with arch involvement remains a challenging task in aortic surgery. The introduction of the frozen elephant trunk (FET) technique offered a link between open surgery and thoracic endovascular aortic repair (TEVAR). Despite a decade of experience, data on the complementary use of these techniques are scant. The aim of this study was to evaluate TEVAR following FET in clinical reality.

METHODS

 Between November 2006 and June 2018, 20 patients (9 females; median age of 69 years) underwent endovascular second-stage completion after FET. The clinical outcomes, technical feasibility, and morphological findings were analyzed retrospectively.

RESULTS

 Eleven of the 20 interventions were intended "rendezvous procedures" in a multistage approach; 4 were elective reinterventions, and 5 were emergency complication repairs. The median interval between FET and TEVAR was 231 days (11 days-7.4 years). The technical success rate was 100%. During a median follow-up (FU) period of 58.3 months, the overall survival rate was 95%, with one in-hospital death. Neurological complications occurred in three cases (spinal cord injury: n = 1; stroke: n = 2). Computed tomography angiography showed overall regression in the median diameter of the proximal descending aorta (from 57 to 48.5 mm).

CONCLUSION

 TEVAR as a second-stage intervention after FET is a feasible option, with satisfactory results at medium-term FU. In extensive thoracoabdominal aortic disease without proximal landing zones, the complementary use of both techniques in a multistage approach should be considered.

Extended thoracic endovascular aortic repair for residual aortic dissection after type A aortic dissection repair

OBJECTIVE

We investigated the outcomes of extended coverage of the descending thoracic aorta by thoracic endovascular aortic repair (TEVAR) for residual chronic type B aortic dissection after type A aortic dissection (TAAD) repair.

METHODS

From November 2015 to August 2020, 36 patients underwent extended TEVAR for residual intimal tear after TAAD repair. We specifically investigated the methods and outcomes of this procedure.

RESULTS

TEVAR consisted of isolated TEVARs (n = 29), single-vessel debranching TEVAR (6), and two-vessel debranching TEVAR (1). The mean time from TAAD repair to TEVAR was 27 ± 33 months (2-86 months). The TEVAR devices used were Valiant (28 cases), GORETAG (4), Relay plus (2), and TX2 (2). Technical success of TEVAR was 100%. The distal ends of the stent grafts were T 8 (1 case), T 9 (5), T 10 (6), T 11 (9), and T 12 (15), with an average of T 11 ± 1. The average length of hospital stay after TEVAR was 9 ± 3 days (5-17 days). There were no surgical/hospital deaths or complications. The average postoperative follow-up period was 21 ± 15 months without death or reintervention.

CONCLUSIONS

The short-term outcomes of extended TEVAR for residual chronic type B aortic dissection after TAAD repair were acceptable without perioperative SCI. Aggressive descending thoracic aorta coverage may prevent aortic events, and extended TEVAR may be a preemptive treatment for the downstream aorta. Mid- to long-term results should be clarified.

Rapidly Progressed Distal Arch Aneurysm with Distal Open Stent Graft-Induced New Entry Caused by "Spring-Back" Force

The J Graft Open Stent Graft (JOSG) is used for the frozen elephant trunk procedure in Japan. We report a 70-year-old male who developed a rapidly progressing distal arch aneurysm caused by a distal stent graft-induced new entry (DSINE) 7 months after the procedure. The JOSG was originally implanted at the curved part of the distal arch. It created its initial DSINE on the greater curve and rapidly "sprang" back in 2 months. Urgent thoracic endovascular aortic repair fixed this serious complication. We should remember such rapid progression of DSINE by JOSG and treat its initial sign earlier.

Is the frozen elephant trunk technique justified for chronic type A aortic dissection in Marfan syndrome?

Background

Chronic type A aortic dissection (cTAAD) in Marfan syndrome (MFS) is rare. Surgical experience is limited and the role of frozen elephant trunk (FET) technique remains undefined. We seek to evaluate the safety and efficacy of the total arch replacement (TAR) and FET technique for cTAAD in MFS.

Methods

The clinical data of sixty-eight patients with MFS undergoing FET and TAR for cTAAD were analyzed.

Results

Mean age was 35.8±9.7 years and thirty-nine were male (57.4%). Operative mortality was 10.3% (7/68). Stroke occurred in one (1.5%), re-exploration for bleeding in five (7.3%), low cardiac output in four (5.9%), and acute renal failure in two (2.9%). Follow-up was complete in 100% (61/61) at mean 7.3±4.0 years. The false lumen was obliterated in 73.5% across FET and 50.0% in unstented descending aorta (DAo). Distal dilation occurred in twenty patients, six of whom underwent thoracoabdominal aortic replacement, one abdominal aortic replacement and one thoracic endovascular aortic repair (TEVAR). Late death occurred in five. At ten years, 59.8% were free from distal aortic dilation, and the incidences were 23.2% for death, 14.4% for distal reoperation, and 62.4% for reoperation-free survival. Predictors for operative mortality were extra-anatomic bypass [odds ratio (OR), 229.592; P=0.036], preoperative maximal size (DMax) of aortic sinuses (mm) (OR, 1.134; P=0.032) and cardiopulmonary bypass (CPB) time (minute) (OR, 1.061; P=0.041). Risk factors for aortic dilatation included patent false lumen at diaphragmatic hiatus [hazard ratio (HR), 5.374; P=0.008], preoperative DMax (mm) of proximal DAo (HR, 1.068; P=0.001) and renal arteries (HR, 1.102; P=0.005) which also predicted distal reoperation (HR, 1.149; P=0.001). The time from onset to operation (day) (HR, 1.002; P=0.004) and CPB time (minute) (HR, 1.032; P=0.036) predicted late death.

Conclusions

This study shows that the TAR and FET technique is a safe and durable approach to cTAAD in patients with MFS. The operation should be performed as early as possible to optimize clinical outcomes.

Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) Reporting Standards for Type B Aortic Dissections

This Society for Vascular Surgery/Society of Thoracic Surgeons (SVS/STS) document illustrates and defines the overall nomenclature associated with type B aortic dissection. The contents describe a new classification system for practical use and reporting that includes the aortic arch. Chronicity of aortic dissection is also defined along with nomenclature in patients with prior aortic repair and other aortic pathologic processes, such as intramural hematoma and penetrating atherosclerotic ulcer. Complicated vs uncomplicated dissections are clearly defined with a new high-risk grouping that will undoubtedly grow in reporting and controversy. Follow-up criteria are also discussed with nomenclature for false lumen status in addition to measurement criteria and definitions of aortic remodeling. Overall, the document provides a facile framework of language that will allow more granular discussions and reporting of aortic dissection in the future.

Redo Descending Aortic Replacement via Direct Anastomosis to J Graft Open Stent Graft

A 64-year-old man with prior history of total arch replacement with frozen elephant trunk was admitted for an enlarging descending thoracic aortic aneurysm. Preoperative computed tomography revealed previously implanted J graft open stent graft, a frozen elephant trunk device approved in Japan, with enlarged dissected aortic aneurysm from distal anastomosis site to the level of the diaphragm. The patient underwent descending aortic replacement. Proximal anastomosis was directly performed at the distal end of the previously implanted J graft open stent graft. Hemostasis at the anastomosis site was uneventful and the patient was discharged from the hospital without any aneurysm-related complication.