Should intentional endovascular stent-graft coverage of the left subclavian artery be preceded by prophylactic revascularisation?

A dedicated preventive protocol sustainably avoids spinal cord ischemia after endovascular aortic repair

Objective

To analyze the incidence of spinal cord ischemia (SCI) after complex endovascular aortic repair (EVAR) after the introduction of a dedicated SCI preventive protocol.

Methods

Retrospective review of all consecutive patients undergoing complex EVAR with branched (BEVAR) and/or fenestrated grafts (FEVAR) during a 6-year period starting January 1st, 2015. The preventive protocol consisted of staging extensive aortic repairs, maintaining a mean arterial pressure (MAP) >80 mm Hg, Hb level >110 g/L, early lower limb reperfusion and neurological control per hour during the post-operative stay in the intensive care unit (36-72 h). Prophylactic cerebrospinal fluid drainage (CSFD) was used selectively. Pre- intra-, and 30-day postoperative clinical data and imaging were collected. Primary end point was the development of perioperative SCI. Secondary outcome included technical and clinical success.

Results

Complex EVAR was performed in 205 patients (167 males, 72 (67-75) years, 182 (88.8%) elective) with juxtarenal aneurysms (JRA, 155 patients) or thoracoabdominal aortic aneurysms (TAAA). SCI occurred after JRA repair in two patients (1.3%, both ruptures) and after TAAA repair in three (6.0%, one rupture) (p = 0.06), all within 9 h postoperatively. There was symptom regression in three cases (one partial, two complete), resulting in a persistent SCI level of 0.6% and 4.0% for JRA and TAAA, respectively. Only one patient with persistent SCI could be discharged from the hospital alive. Patients developing SCI were more commonly female (n = 3, p = .016), presented with rupture (n = 3, p < .001), had preoperative renal insufficiency (n = 5, p < .001) and had lower minimal MAP (p = .015). No regression analysis was done due to the limited number of SCI events in relation to the study population size. Primary technical success was achieved in 162 patients (83.5%) and clinical success in 153 patients (75.4%), without any differences between the groups.

Conclusions

The incidence of persistent SCI after complex EVAR is low with the use of a dedicated SCI preventive protocol allowing the early diagnosis. Females, patients with ruptured aneurysms and preoperative renal insufficiency are at higher risk. Further studies are needed to customize the protocols particularly in those high-risk patients.

The Call for the "Interventional/Hybrid" Aortic Surgeon: Open, Endovascular, and Hybrid Therapies of the Aortic Arch

Aortic arch pathology is relatively rare but potentially highly fatal and associated with considerable comorbidity. Operative mortality and complication rates have improved over time but remain high. In response, aortic arch surgery is one of the most rapidly evolving areas of cardiac surgery in terms of surgical volume and improved outcomes. Moreover, there has been a surge in novel devices and techniques, many of which have been developed by or codeveloped with vascular surgeons and interventional radiologists. Nevertheless, the extent of arch surgery, the choice of nadir temperature, cannulation, and perfusion strategies, and the use of open, endovascular, or hybrid options vary according to country, centre, and surgeon. In this review article, we provide a technical overview of the surgical, total endovascular, and hybrid repair options for aortic arch pathology through historical developments and contemporary results. We highlight key information for surgeons, cardiologists, and trainees to understand the management of patients with aortic arch pathology. We conclude by discussing training paradigms, the role of aortic teams, and gaps in knowledge, arguing for the need for wire skills for the future "interventional aortic surgeon" and increased research into techniques and novel devices to continue improving outcomes for aortic arch surgery.

Comparison of techniques for left subclavian artery preservation during thoracic endovascular aortic repair: A systematic review and single-arm meta-analysis of both endovascular and surgical revascularization

Background

Currently, the optimal technique to revascularize the left subclavian artery (LSA) during thoracic endovascular aortic repair (TEVAR) remains controversial. Our study seeks to characterize early and late clinical results and to assess the advantages and disadvantages of endovascular vs. surgical strategies for the preservation of LSA.

Methods

PubMed, Embase and Cochrane Library searches were conducted under the PRISMA (Preferred Reporting Items for Systematic review and Meta-Analyses) standards. Only literature published after January 1994 was included. Studies reporting on endovascular revascularization (ER), surgical revascularization (SR) for LSA preservation were included. 30-day mortality and morbidity rates, restenosis rates, and rates of early and late reintervention are measured as outcomes.

Results

A total of 28 studies involving 2,759 patients were reviewed. All articles were retrospective in design. Single-arm analysis found no significant statistical differences in ER vs. SR in terms of 30-day mortality and perioperative complication rates. The mean follow-up time for the ER cohort was 12.9 months and for the SR cohort was 26.6 months, respectively. Subgroup analysis revealed a higher risk of perioperative stroke (4.2%) and endoleaks (14.2%) with the chimney technique compared to the fenestrated and single-branched stent approaches. Analysis of the double-arm studies did not yield statistically significant results.

Conclusion

Both ER and SR are safe and feasible in the preservation of LSA while achieving an adequate proximal landing zone. Among ER strategies, the chimney technique may presents a greater risk of neurological complications and endoleaks, while the single-branched stent grafts demonstrate the lowest complication rate, and the fenestration method for revascularization lies in an intermediate position. Given that the data quality of the included studies were relatively not satisfactory, more randomized controlled trials (RCTs) are needed to provide convincing evidence for optimal approaches to LSA revascularization in the future.

Headache may be the only symptom of subclavian steal syndrome after thoracic endovascular aortic repair

Thoracic endovascular aortic repair (TEVAR) is currently the treatment of choice for thoracic aortic disease. In select cases, the TEVAR stent must occlude the left subclavian artery. This is usually well tolerated, but the subclavian steal syndrome (SCSS) may occur. Vertebrobasilar insufficiency can cause headaches, but reports of headache as the only symptom of SCSS are very rare. Thus, this may be under-recognised. To increase the awareness of this complication we describe the course of a patient who developed chronic intermittent headaches after intentional occlusion of the left subclavian artery with a TEVAR stent. Revascularisation may be required to prevent adverse neurological outcomes from SCSS. Some authors recommend prophylactic revascularisation whenever the left subclavian artery is sacrificed during TEVAR. However, transposition or bypass of this artery is not without risk and mild symptoms, such as secondary headache, can be fully controlled with conservative measures that reduce steal pathophysiology.

Covering/Overstenting of the left subclavian artery (LSA) in thoracic endovascular repair (TEVAR) to treat various thoracic/thoracoabdominal aortic lesions: Is revascularization of the left arm a must? (A retrospective cohort study with 12 years of experience to describe the real-world situation of daily clinical practice and the literature review)

Background: Pathologies of the descending thoracic aorta inwardly extended towards the aortic arch actually shorten the proximal landing zone for aortic prosthesis. This, in turn, worsens the feasibility of the aorta for endovascular therapeutic options of those pathologies. Objective: This work considers the blockage of the left subclavian artery (LSA) through endovascular treatment of the pathologies of the descending aorta as a main work question, which is based on the hypothesis that there is no necessity for primary standard revascularization of the LSA in TEVAR with LSA covering. The researchers have 12 years of experience in treatment of different thoracic aortic lesions. Their experience will also be reviewed in this paper. Design: Retrospective unicenter cohort study in consecutive patients order to describe the real-world situation of daily clinical practice Material: All the patients who had undergone endovascular, hybrid, or open operative therapy of variant pathologies of descending aorta were included in this study. Methods: Various parameters were investigated, including therapeutic procedures such as i) pure endovascular vs. hybrid; ii) year of therapy; iii) symptomatic vs. asymptomatic status of the patients; iv) variant epidemiological factors (age, sex, risk factors, mortality, and follow up); v) overstenting/blocking of the LSA; vi) complications of applied therapies; vii) further operations/interventions to treat such complications; viii) radiologic aortic measurements (such as lumen extensions, false lumen measurements, distance to the supra-aortic and visceral vessels); and ix) multiple other pathological features. Different statistical parameters were also examined. Survival was analysed by the Kaplan–Meier assessment in the group of whole patients vs. the group of over-stented patients. Here the analysis of variance is performed for the independent parameters for the revascularized patients—not the revascularized patients—who had undergone LSA coverage. For statistical approval, U-test was used. The p-value < 0.05 was considered significantly different. The literature review was achieved by a search in PubMed, Google scholar, Research Gate, ScienceDirect, and Cochrane library by using the following terms endovascular, TEVAR, revascularization, stroke, and left-subclavian-artery ischemia. The literature is classified accordingly in relation to the main topic. In fact, the literature undergoes further analysis if it goes with or against our hypothesis. Results: Overall, 112 patients were enrolled in the study. There was no significant difference comparing the not-revascularized vs. the revascularized group of patients, considering the consequences on cerebrovascular blood circulation (in particular, n=1 case [4.8 %] vs. no case [0 %]; p=1) or the spinal cord ischemia (n=2 [9.5 %] vs. n=1 [7.1 %]; p=1). As the main result, there was no case of manifest left arm ischemia and deaths (mortality, 0). Survival was in both groups as follows: 22 [95% CI, 14.154–29.904] months vs. 43 [95% CI, 33.655–51.921] months with no significant statistical difference (p>0.05) . The only statistically significant risk factor found was renal insufficiency (p, 0.028), but this too is considered a trend by the urgency of revascularization. Postoperatively, pneumonia showed a trend of higher frequency (p=0.058) in the revascularized cases (n=0 in the not-revascularized vs. n=3 [21.4 %] in the revascularized cases). There was no significant difference in the occurance of postoperative neurovascular complications (such as cerebrovascular accidents, spinal cord ischemia, or left arm ischemia) by comparing the groups of not-revascularized and revascularized patients. Conclusion: The revascularization of the overstented LSA due to TEVAR should be limited to certain indications, including i) the inadequate intracerebral circle of Willis; ii) the predominantly perfused left vertebral artery with inadequate blood perfusion via the right vertebral artery (e.g., by stenosis), iii) anatomic variance such as the left vertebral artery originating directly from the aortic arch (and must be blocked by TEVAR); iv) the need of an adequate left internal thoracic artery for coronary-artery-bypass grafting (CABG); v) the need of patent LSA for the dialysis shunt of the left arm. However, there is no appropriate evidence as yet based on sufficient study results achieved in trials with an advanced design (such as [double-]blind, multicenter randomized study) that appears to be urgently required.

Early experience with the Bolton Relay Pro/Plus for physician-modified fenestrated TEVAR

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) can be challenging in cases involving the aortic arch and the visceral segment. We report our initial experience with fenestrated TEVAR (f-TEVAR) for thoracic aortic disease involving aortic branches using physician-modified stent grafts (PMSGs).

MATERIALS AND METHODS

Between February 2019 and November 2020 nine patients were treated with a PMSG. Indication to treatment were a symptomatic acute type B aortic dissection (TBAD) in three cases, a penetrating aortic ulcer in three cases (two in zone 3 and one in zone 6), one case of an endoleak type I A after TEVAR, a chronic TBAD after TEVAR in one case and one case of a contained rupture of a thoracoabdominal aneurysm in zone 3. Pre-, intra- and postoperative clinical data were recorded.

RESULTS

The median patient age was 65 (IQR 60.5-71) years, and 8 (89%) patients were men. Nine stent grafts (six Bolton Relay Plus and three Bolton Relay Pro, Terumo Aortic, Vascutek Ltd., Inchinnan, United Kingdom) were deployed. Small fenestrations (8 mm) were created on table, median duration for on table stent graft modifications was 20 minutes (13-22). The technical success rate was 100%. Median operative time was 188 (116-252) minutes. No major adverse events of any sort occurred during the first 30-day postoperatively. There were no type I or type III endoleaks at the end of the procedure, and no cases of spinal cord ischemia. Two access related complications occurred (22%). After a median of 12 (range 5-12) months all patients survived and all target vessels remained patent with one case of fenestration-related type I endoleak, which required open conversion.

CONCLUSIONS

The results of our initial experience with f-TEVAR using PMSGs with the Bolton Relay stentgraft for the treatment of aortic diseases are acceptable. These results should be confirmed on larger patient cohorts.

Association of carotid ultrasonography with perioperative stroke after thoracic aortic aneurysm treatment: a retrospective study

PURPOSE

The purpose of this study was to verify whether carotid ultrasonography (CUS) findings could be associated with the occurrence of perioperative stroke after thoracic aortic aneurysm (TAA) treatment.

METHODS

Patients with TAAs who were treated by either total arch replacement or thoracic endovascular aortic repair (TEVAR) were retrospectively enrolled. Left subclavian artery (LSA) embolization and bypass surgery of the left common carotid artery (CCA) to the LSA before TEVAR were additionally performed for some patients. CUS was performed before TAA treatment to evaluate carotid atherosclerosis and flow velocities of bilateral cervical arteries. After dividing patients into those with and without perioperative stroke, their background, atherosclerotic risk factors, history of stroke, TAA location and size, treatment procedures, and CUS parameters were compared between the two groups.

RESULTS

Of the 60 patients (18 women, 42 men; mean age 73.5 ± 10.2 years) with TAA, four (7.5%) developed perioperative stroke. There were no significant differences in the patients' characteristics and their TAAs between those with and without perioperative stroke. For the CUS parameters, end-diastolic velocity (EDV) of bilateral CCAs was significantly decreased in perioperative stroke patients (with vs without stroke; right: 9.2 ± 1.8 vs. 14.5 ± 4.6 cm/s, P = 0.025, left: 9.1 ± 0.3 vs. 15.0 ± 4.5 cm/s, P = 0.012), whereas the resistance index (RI) of bilateral CCAs was significantly elevated (right: 0.76 vs. 0.87, P = 0.008, left: 0.76 vs. 0.87, P < 0.001).

CONCLUSIONS

Lower EDV and higher RI of bilateral CCAs were significantly associated with perioperative stroke after TAA treatment. Thus, CUS findings may help predict the occurrence of perioperative stroke.

Endovascular aortic arch repair using a double-branched approach

The last 15 years have overwhelmed the surgical community with a range of approaches in treating pathologies involving the aortic arch of which some are here to stay. The ones to stay are-in the authors' opinion-refined classical surgical approaches such as the frozen elephant trunk technique, near-orthotopic combined vascular and endovascular approaches such as subclavian to carotid transposition/bypass and double transposition, and finally, near-orthotopic advanced endovascular solutions such as the double-endovascular repair using fenestrated and/or branched solutions which will be the main focus of this article.

Effects of preemptive cerebrospinal fluid drainage on spinal cord protection during thoracic endovascular aortic repair

BACKGROUND

Spinal cord injury (SCI) is reported to occur in 3-12% of thoracic endovascular aortic repair (TEVAR) cases, but is a potentially preventable complication of TEVAR for thoracoabdominal pathologies. Although many strategies have been devised to reduce the incidence of SCI, the effectiveness of prophylactic cerebrospinal fluid drainage (CSFD) and left subclavian artery (LSA) revascularization remains controversial.

METHODS

From 2012 to 2014, 162 patients underwent TEVAR at a single institution. We prospectively collected and retrospectively reviewed the data of 81 patients who underwent preoperative CSFD among the 162 patients. LSA revascularization was routinely used when LSA need to be covered. Preoperative characteristics, intraoperative variables, and outcomes were analyzed.

RESULTS

The mean (SD) age of the patients was 60.6 (12.5) years, and 57 patients (70%) were male. Twenty-five patients (31%) presented with degenerative aneurysm; 48 (59%), type B dissection; 5, (6%) penetrating aortic ulcer; and 3 (4%), intramural hematoma. Thirty-six patients (44%) underwent LSA revascularization before TEVAR. Two (2.5%) of the patients who underwent preoperative CSFD had SCI, of whom one recovered ambulatory status at discharge after hypertensive therapy and another had a permanent disability. Prior abdominal aortic aneurysm (AAA) repair tended to relate to SCI (P=0.065), and preoperative aortic rupture was a significant independent risk factor of SCI (P=0.002).

CONCLUSIONS

Preemptive CSFD as an adjunctive procedure to TEVAR proved to be more effective than selective use of CSFD in other prior reports of SCI cases. Preoperative CSFD is recommended as a prophylactic procedure in patients at high risk of SCI during TEVAR.

Proximal scalloped custom-made Relay® stent graft in chronic type B dissection: endovascular repair in a drug abuser patient

The best solution for enlarging chronic type B aortic dissection is not known. Hybrid surgical and endovascular procedures offer a reliable solution in such circumstances, but technically complex stent-graft designs are sometimes needed when the treatment segment of the aorta presents anatomical challenges. We report a case of a proximally scalloped custom-made stent-graft implantation following left subclavian artery transposition in a formerly cocaine-abuser patient. The one-month follow-up computed tomography angiography showed a proximal endoleak (type Ia) which was successfully solved by coil embolization. Proximally scalloped stent grafts offer a reliable solution in complex aortic dissections involving the supra-aortic branches.

Differential aspects of the disease and treatment of Thoracic Acute Aortic Dissection (TAAD)-the European experience

The management of patients with acute aortic dissection continues to be a challenge. It is an uncommon but lethal condition which continues to be under-diagnosed and under-treated. In this review, the term acute aortic syndrome is preferred in order to embrace the closely related pathologies of intramural hematoma (IMH) and penetrating aortic ulcer (PAU).

Revascularisation of the left subclavian artery for thoracic endovascular aortic repair

BACKGROUND

Controversy exists as to whether revascularisation of the left subclavian artery (LSA) confers improved outcomes in patients undergoing thoracic endovascular aortic repair (TEVAR). Even though preemptive revascularisation of the LSA has theoretical advantages, including a reduced risk of ischaemic damage to vital organs, such as the brain and the spinal cord, it is not without risks. Current practice guidelines recommend routine revascularisation of the LSA in patients undergoing elective TEVAR where achievement of a proximal seal necessitates coverage of the LSA, and in patients who have an anatomy that compromises perfusion to critical organs. However, this recommendation was based on very low-quality evidence.

OBJECTIVES

To assess the comparative efficacy of routine LSA revascularisation versus either selective or no revascularisation in patients with descending thoracic aortic disease undergoing TEVAR with coverage of the LSA origin.

SEARCH METHODS

The Cochrane Vascular Trials Search Co-ordinator (TSC) searched the Specialised Register (June 2015). In addition, the TSC searched the Cochrane Register of Studies (CENTRAL (2015, Issue 5)).Trials databases were also searched (June 2015).

SELECTION CRITERIA

We had planned to consider all randomised controlled trials (RCTs) that compared routine revascularisation of the LSA with selective or no revascularisation, in patients undergoing TEVAR.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the title and abstract of articles identified through literature searches. An independent third review author was consulted in the event of disagreement. We had planned for two review authors to independently extract data and assess the risk of bias of identified trials using the criteria recommended in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We did not identify any RCTs relevant to our review topic. Therefore, no quantitative analysis was conducted.

AUTHORS' CONCLUSIONS

High quality RCT evidence for or against routine or selective revascularisation of the LSA in TEVAR is not currently available. It is not possible to draw conclusions with regard to the optimal management of LSA coverage in TEVAR, and whether routine revascularisation, which was defined as the intervention of interest in our review, confers beneficial effects, as indicated by reduced mortality, cerebrovascular events, and spinal cord ischaemia. This review highlights the need for continued research to provide RCT evidence and define the role of LSA revascularisation in the context of TEVAR with coverage of the LSA.

Alternative management of the left subclavian artery in thoracic endovascular aortic repair for aortic dissection: a single-center experience

Background

Since the new 2009 guidelines for left subclavian artery (LSA) management using thoracic endovascular aortic repair (TEVAR), a few studies have been published about alternative LSA management. The objective of this study was to present the follow-up results of covered or revascularized LSA during TEVAR.

Methods

From January 2010 to August 2012, 109 consecutive patients were treated with TEVAR at the Department of Vascular Surgery, Changhai Hospital, for aortic dissection extending near the LSA. After evaluating the bilateral vertebral arteries, fifty-two LSAs were covered and not revascularized (covered group), while 57 LSAs were preserved (revascularized group). Complications were stratified according to the time of occurrence after surgery.

Results

Emergency operations were more common (17.3 vs. 3.5 %, P = 0.017) and operation time was shorter (96.9 ± 16.3 vs. 135.3 ± 38.4 min, P < 0.001) in the covered group. Pulselessness and intermittent claudication of the left arm occurred in most patients in the covered group (P < 0.001). Incidence of stroke and cold shoulder feeling were higher in the covered group compared with the revascularized group (P = 0.026 and <0.001, respectively). There were five aorta-related deaths in the covered group and one in the revascularized group. Eight endoleaks were observed in the revascularized group (P = 0.006).

Conclusions

The results of this study suggest that due to occurrence of complications, LSA should be preserved or revascularized to reduce complications and to improve patients’ quality of life.

The chimney technique for preserving the left subclavian artery in thoracic endovascular aortic repair

OBJECTIVES

The objective of the present study was to evaluate short- and mid-term outcomes of the left subclavian artery (LSA) chimney stent implantation (LSACSI) during thoracic endovascular aortic repair (TEVAR), and to summarize our experience with this technique.

METHODS

From June 2010 to September 2012, 59 patients (49 men; mean age of 57.4 ± 13.3 years, range from 26 to 83 years) who underwent TEVAR and LSACSI were enrolled. Patients suffered from Stanford type B aortic dissection (n = 27), penetrating aortic ulcer (n = 18), aortic arch aneurysm (n = 9), pseudoaneurysm of the aortic arch (n = 4) and proximal type I endoleak after TEVAR of aortic dissection (n = 1). Elective settings were performed in 72% and emergent in 38% of all patients. Follow-up was performed at postoperative 3 months, 6 months and yearly thereafter.

RESULTS

The technical success rate was 98.3% (58/59), and 69 thoracic stent grafts were used. Sixty-two chimney stents, including 55 uncovered and 7 covered stents, were implanted in 59 LSAs. The overall immediate endoleak rate was 15.3% (9/59); type I endoleak was observed in 5 patients and type II in 4 patients. The difference in the immediate endoleak rate related to the anatomy between the outer and the inner curvature was statistically significant (35 vs 4%, P = 0.018). Chimney stent compression was observed in 3 patients and another stent was deployed inside the first one. Perioperative complications included stroke (3.4%, 2/59) and left upper limb ischaemia (1.7%, 1/59). The median follow-up period was 16.5 (range 1–39 months). The mortality rate during follow-up was 5.4% (3/56). Complications during follow-up included endoleak [overall, n = 8 (14.3%, 8/56); type I, n = 5; type II, n = 3], retrograde type A aortic dissection (n = 1), collapse (n = 3, 5.4%) or occlusion (n = 2, 3.6%) of the chimney stent.

CONCLUSIONS

Short- and mid-term results showed that it is feasible to preserve the patency of the LSA in TEVAR with the chimney technique for thoracic aortic pathologies close to the LSA. However, TEVAR combined with LSACSI was not advocated for lesions located at the outer curve of the aortic arch due to a high possibility of endoleak.

Thoracic endovascular aortic repair with left subclavian artery coverage without prophylactic revascularisation-early and midterm results

Background

The management of the left subclavian artery when coverage is necessary during thoracic aorta endografting remains a matter of debate.

Materials and methods

A retrospective analysis of a single-centre experience with thoracic endovascular aorta repair (TEVAR) was performed. Between April 2004 and October 2012, 125 cases of TEVAR were performed. The analysis focused on patients who required coverage of the left subclavian artery (LSA). We analysed mortality and morbidity with special attention to the rates of cerebrovascular accidents (CVAs) and spinal cord ischaemia (SCI) in the early and midterm.

Results

Of the 125 patients, 53 (42 %, group A) required an intentional coverage of the LSA to obtain an adequate proximal seal for the endograft; the remaining patients constituted group B. None of the patients in group A had protective LSA revascularisation prior to TEVAR. The primary technical success rate was 79.2 vs. 90.3 % (group A vs. group B, p = 0.08), and the primary clinical success rate was 77.4 vs. 82 % (group A vs. group B, p = 0.53). The 30-day mortality rate was 11.3 vs. 11.1 % (group A vs. group B, p = 0.97). The 30-day morbidity was 7.5 vs. 13.9 % (group A vs. group B, p = 0.4). CVA occurred in 1.9 % of group A patients, compared to 1.4 % of patients from group B (p = 0.82). The SCI incidence rate was 0 vs. 1.4 % (p = 0.39). The mean follow-up of group A was 24.1 months (range 2–64.6 months, SD = 19). Additionally, the 1-year estimated survival was 85.5 %, and the 3-year estimated survival was 78 %. There were no midterm CVAs; one event of SCI occurred in the seventh post-operative month in group A.

Conclusion

Our analysis, although retrospective and based on one institution experience, shows a realistic population of TEVAR patients. We prove that TEVAR with coverage of LSA origin can be accomplished with minimal neurological morbidity in this patient population. The study shows that LSA revascularisation is not mandatory before endograft deployment, especially in emergency settings. We also prove that although zone 2 TEVAR extends the proximal landing zone, it does not prevent type IA endoleaks from appearing. A multicentre randomised control trial with higher number of patients is necessary for proper, robust conclusion to be established.

Vertebral artery variations in thoracic aortic patients

OBJECTIVES

Arterial variation is common in the vertebral artery, and simple occlusion of the left subclavian artery may result in brain infarction, especially when it terminates in the posterior inferior cerebellar artery (PICA). We report the results of preoperative vertebral artery evaluation by magnetic resonance angiography (MRA) and its impact upon operative strategy.

METHODS

Among the 214 patients who underwent thoracic aortic surgery from 2009 through 2012, 159 patients with preoperative MRA were retrospectively analysed. Patients' age ranged from 35 to 88 (median 72), 122 were male and 115 had degenerative aneurysms. Prevalence rates of vertebral artery variations and occlusive lesions were reported, together with operative strategies and outcomes.

RESULTS

There were 19 hypoplasia (12%), 10 PICA termination (6%) and 12 occlusive lesion (8%) on the right vertebral artery and 10 hypoplasia (6%), 5 PICA termination (3%), 7 direct arch origin (4%) and 3 occlusive lesion (2%) on the left. Two of the seven arch-originated arteries terminated in the PICA. In aortic arch replacement, these were reconstructed together with the left subclavian artery while hypothermia was maintained. During thoracic endovascular aortic repair with Zone-2 proximal landing, debranching bypass was employed to preserve left subclavian perfusion when there was PICA termination, hypoplasia or occlusive lesion. In 1 patient with hypoplasia between the basilar artery and the left PICA, bypass was added immediately after deployment because radial pressure dropped critically. No brain infarction occurred with this strategy.

CONCLUSIONS

PICA termination and right side hypoplasia/occlusive lesion, where left subclavian perfusion is important for brain protection, is present in ∼ 30%. Left vertebral artery that originated from the arch should be managed with care, because PICA termination is highly prevalent.

Elephant trunk technique for hybrid aortic arch repair

The original elephant trunk technique was developed by Borst in 1983 for the treatment of aortic arch aneurysms. This technique reduced operative risks, but was associated with cumulative mortality rates of 6.9 % for the first stage and 7.5 % for the second stage. Patients also waited a long time between two major surgical procedures. Only 50.4 % of patients underwent the second-stage surgery, and there was a significant interval mortality rate of 10.7 %. With the advent of stent-graft techniques, two different hybrid elephant trunk techniques were developed. One technique is first-stage elephant trunk graft placement followed by second-stage endovascular completion. The conventional elephant trunk graft provides a good landing zone for the stent-graft, and endovascular completion is a useful alternative to conventional second-stage surgery. This method has few major complications, and a postoperative paraplegia rate of 1.1 %. The other technique is the frozen elephant trunk technique. This technique eliminates the need for subsequent endovascular completion, and is particularly useful for the treatment of acute type A dissection because it can achieve a secure seal. However, it is associated with a higher rate of spinal cord ischemia than other methods such as the original elephant trunk technique. The left subclavian artery (LSA) is often lost when performing a hybrid elephant trunk procedure. Revascularization of the LSA should be performed to prevent arm ischemia and neurological complications such as paraplegia or stroke, although the level of evidence for this recommendation is low.

Endovascular repair with the chimney technique for Stanford type B aortic dissection involving right-sided arch with mirror image branching

PURPOSE

To report endovascular repair with the chimney technique of type B aortic dissection involving a right-sided aortic arch (RAA).

CASE REPORTS

Two hypertensive men aged 48 and 42 years with symptoms of aortic dissection resistant to medical therapy underwent emergent thoracic endovascular aortic repair with the chimney technique to extend the proximal landing zones. Both patients had right-sided arches with mirror image branching. One patient required a bare metal chimney stent to maintain perfusion to the right subclavian artery, while the other patient had a chimney stent to revascularize the right common carotid artery. Short-term follow-up (1 year and 1 month, respectively) showed that there was positive aortic remodeling, and the chimney stents were patent.

CONCLUSION

Chimney TEVAR seems safe and effective for Stanford type B dissection in patients having RAA with mirror image branching and no sufficient proximal fixation zone.

Total arch replacement with long elephant trunk anastomosed at the base of the innominate artery: a single-centre longitudinal experience

OBJECTIVE

Total arch replacement, with a long elephant trunk (ET) anastomosed at the base of the innominate artery using an undersized graft, is performed for a variety of arch aneurysms. We investigated the long-term clinical outcomes of this procedure, as well as its long-term effectiveness for preventing retrograde flow into the aneurysm and further dilation of the descending aorta.

METHODS

We treated 127 consecutive patients with an arch aneurysm, who were divided into two groups according to the diameter of the descending aorta at the Th6-Th8 thoracic vertebral level: 35 mm or less (Single-ET, n = 94) and >35 mm (Staged-ET, n = 33). The graft diameter was undersized by 10-20% of the distal aortic diameter. ET length was determined by preoperative computed tomography (CT) to locate the distal end at Th6-Th8. Thrombosis around the ET and the descending aorta diameter around the distal end of the ET were evaluated using CT.

RESULTS

Two patients (1.6%) died within 30 days, while seven (5.5%) died in the hospital, three (2.4%) had a new stroke, three (2.4%) had permanent paraplegia and one (0.8%) had paraparesis. CT demonstrated complete thrombosis of the perigraft space around the ET in 81 patients (86%) in the Single-ET group and 11 (33%) in the Staged-ET group within 1 month after surgery, but not in the remaining 35 patients. Twenty-seven of the 35 patients without complete thrombosis underwent a subsequent second-stage operation. In those, the descending aorta showed no further dilation around the distal end of the ET, while new-onset perigraft perfusion occurred in two patients in the Single-ET group at 14 and 126 months, respectively. Overall survival was 89, 86, 78 and 74% at 1, 3, 5 and 7 years, respectively.

CONCLUSIONS

Our operative strategy for extensive thoracic aortic aneurysms using a long ET technique yielded satisfactory short- and long-term outcomes.