Stent graft repair in the aortic arch and descending thoracic aorta: a 4-year experience

Atypical presentation of subclavian steal syndrome with left sided sensorineural deafness

We present a rare manifestation of a common pathology: left sided sensorineural hearing loss secondary to subclavian steal syndrome after thoracic endovascular aortic repair for complicated acute aortic dissection. We describe the vascular physiology that can result in unilateral hearing loss and provide a brief review of subclavian steal syndrome. This case report highlights the importance of avid clinical recognition of an atypical presentation of a common vascular disease.

[Intervention for Chest Trauma and Large Vessel Injury]

Trauma is an injury to the body that involves multiple anatomical and pathophysiological changes caused by forces acting from outside the body. The number of patients with trauma is increasing as our society becomes more sophisticated. The importance and demand of traumatology are growing due to the development and spread of treatment and diagnostic technologies. In particular, damage to the large blood vessels of the chest can be life-threatening, and the sequelae are often severe; therefore, diagnostic and therapeutic methods are becoming increasingly important. Trauma to non-aortic vessels of the thorax and aorta results in varying degrees of physical damage depending on the mechanism of the accident and anatomical damage involved. The main damage is hemorrhage from non-aortic vessels of the thorax and aorta, accompanied by hemodynamic instability and coagulation disorders, which can be life-threatening. Immediate diagnosis and rapid therapeutic access can often improve the prognosis. The treatment of trauma can be surgical or interventional, depending on the patient's condition. Among them, interventional procedures are increasingly gaining popularity owing to their convenience, rapidity, and high therapeutic effectiveness, with increasing use in more trauma centers worldwide. Typical interventional procedures for patients with thoracic trauma include embolization for non-aortic injuries and thoracic endovascular aortic repair for aortic injuries. These procedures have many advantages over surgical treatments, such as fewer internal or surgical side effects, and can be performed more quickly than surgical procedures, contributing to improved outcomes for patients with trauma.

A Comprehensive Research Schema for the Characterization of Aortic Aneurysms

A robust, accurate, and standardized approach to measurement of the aorta is critical to improve the predictive accuracy of these aortic measurements, and to investigate other aortic imaging biomarkers. Developing a comprehensive and generic schema for characterization of the aorta to enable investigators to standardize data that are collected across all aorta research. A systematic review of the literature was conducted to identify and assess schemata of aortic measurement and description. The schemata were reported and discussed to guide the synthesis of a comprehensive schema. We propose the International College of Angiology Aortic Research Schema as a comprehensive design that fills the gaps left behind by previously reported schemata. It is intended to be applicable for all clinically relevant purposes, including endograft development for aneurysm repair and for the accurate characterization of the aortic anatomy. This schema divides the aorta into 14 segments and 2 sections (thoracic and abdominal aortas). The segmentation proposed can be used in addition to specific measurements taken for any aneurysm including the neck, and maximal and minimal diameters of the aneurysm.

Emergency Endovascular Interventions on Descending Thoracic Aorta: A Single-Center Experience

Background

Implementation of emergency endovascular aortic repair provides an attractive opportunity in the treatment of complicated acute aortic syndromes involving descending aorta.

Aim

The aim of this study was to analyze the effectiveness of thoracic endovascular aortic repair (TEVAR) for the treatment of acute surgical emergencies involving the descending thoracic aorta.

Methods

A retrospective review of the medical records of all patients undergoing TEVAR in a single center since 2007 was undertaken. Patients with the aortic disease treated on emergency inclusion criteria were complicated spontaneous acute aortic syndrome (csAAS), traumatic aortic acute injuries (TAIs), and other indications requiring emergent intervention. Technical and clinical success with patient mortality, survival, and reoperation rate was evaluated according to Society for Vascular Surgery reporting standards for thoracic endovascular aortic repair (TEVAR).

Results

The emergency interventions were necessary in 74 cases (51.0%), including patients with the complicated spontaneous acute aortic syndrome (csAAS) (64.8%; n = 48) and traumatic aortic acute injuries (TAIs) (31.1%). In addition, in one case aortic iatrogenic dissection (AID) and in 2 other fistulas after the previous stent graft, implantations were diagnosed. All procedures were done through surgically exposed femoral arteries while 2 hybrid procedures required additional approaches. The primary technical success rate was 95.9%, in 3 cases endoleak was reported. The primary clinical success occurred in 94.5%. All patients survived the endovascular interventions, whereas during in-hospital stay one of them died due to multiorgan failure (early mortality 1.3%). During the follow-up period, lasting 6 through 164 months (median 67), 11 patients died. Annual, five- and ten-year probability of survival was 86.4 ± 0.04%, 80.0 ± 0.05%, and 76.6 ± 0.06%, respectively. However, the rate of 5-year survivors was significantly higher after TAI (95.2%) than scAAS (63.4%) (p=0.008). Early after the procedure, one individual developed transient paraparesis (1.3%). No other serious stent-graft-related adverse events were noted within the postdischarge follow-up period.

Conclusions

Descending aortic pathologies requiring emergent interventions can be treated by endovascular techniques with optimal results and low morbidity and mortality in an experienced and dedicated team.

Blunt Thoracic Aortic Injury and Contemporary Management Strategy

Thoracic aortic injury (TAI) is a leading cause of death in blunt chest trauma. Motor vehicle collisions are the commonest cause, and most patients die before receiving medical attention. Survivors who make it to the hospital also typically have other debilitating injuries with high morbidity. It is imperative to understand the nature of these injuries and implement current management strategies to improve patient outcomes. A literature review on contemporary management strategies on blunt thoracic aortic injuries was performed to evaluate the available evidence using online databases (PubMed and Google Scholar). We found that there has been an improved survival owing to the current advancement in diagnostic modalities, the use of contrast-enhanced computed tomography angiography, and contemporary management techniques with an endovascular approach. However, careful assessment of patients and a multidisciplinary effort are necessary to establish an accurate diagnosis. Minimal aortic injuries (intimal tear and aortic hematoma) can be managed medically with careful monitoring of disease progression with imaging. Endovascular approaches and delayed intervention are key strategies for optimal management of high-grade TAI.

Safety of Left Subclavian Artery Selective Coverage without Revascularization in Thoracic Endovascular Aortic Repair for Type B Aortic Dissections

PURPOSE

Whether to proceed left subclavian artery (LSA) revascularization in patients with LSA coverage due to insufficient proximal landing zone (PLZ) during thoracic endovascular aortic repair (TEVAR) remains controversial.

METHODS

A total of 903 patients who received TEVAR were retrospectively analyzed. LSA could be covered if the PLZ was less than 15 mm accompanied with 1) a dominant or balanced right vertebral artery, 2) a complete circle of Willis, and 3) a left vertebral artery with a diameter ≥3 mm and without severe stenosis.

RESULTS

LSA selective coverage was necessary for 35.0% (316/903) of the patients to extend the PLZ. Patients presented with weakness, pain, cooling and discoloration of the left upper extremity (LUE), and pulselessness of the left brachial artery were more in the LSA-covered group. The ischemia of LUE occurred more often in patients with LSA covered completely than in those with LSA covered partially. Functional arm status showed no significant difference in the arm, shoulder, and hand questionnaire scores at 12 months postoperative between the LSA-covered group and LSA-uncovered group, or between the LSA-covered completely group and LSA-covered partially group.

CONCLUSION

It was safe to cover the LSA origin without revascularization if the PLZ was less than 15 mm accompanied with careful evaluation (description in method).

Systematic review and meta-analysis of association of prophylactic cerebrospinal fluid drainage in preventing spinal cord ischemia after thoracic endovascular aortic repair

OBJECTIVE

We conducted a systemic review and meta-analysis to compare the association between prophylactic cerebrospinal fluid drainage (CSFD) vs non-CSFD in preventing spinal cord ischemia (SCI) after thoracic endovascular aortic repair (TEVAR) for aneurysm and dissection.

METHODS

The MEDLINE, Embase, and Cochrane databases were systematically searched to identify all relevant studies reported before April 1, 2020. A systematic review and meta-analysis were performed. We assessed the association between CSFD strategies, including routine CSFD vs selective CSFD or no CSFD, and the SCI rates after TEVAR for patients with aortic dissection (AD), solitary thoracic aortic aneurysm (TAA), or thoracoabdominal aortic aneurysm (TAAA). Subgroup analyses were conducted to assess the association between different aortic pathologies, including AD and thoracic aneurysms, and SCI rates after TEVAR with and without prophylactic CSFD. The data are presented as the pooled event rates (ERs) and 95% confidence intervals (CIs).

RESULTS

A total of 34 studies of 3561 patients (2671 with TAA or TAAA and 890 with type B AD) were included in the present analysis. The data are presented as the pooled ERs and 95% CIs. The overall SCI rate for patients who had undergone TEVAR with prophylactic CSFD for AD (ER, 1.80%; 95% CI, 0.88%-2.72%) was significantly lower than that for the aortic aneurysm group (ER, 5.73%; 95% CI, 4.20%-7.27%; P < .0001). The SCI rate after TEVAR with prophylactic CSFD was not significantly different from that without CSFD for AD (P = .51). No association was found between the rates of SCI after TEVAR with routine prophylactic CSFD vs selective prophylactic CSFD for aortic aneurysms (P = .76) and AD (P = .70). The SCI rate after TEVAR without CSFD for aortic aneurysms, including isolated TAA and TAAA (ER, 3.49%; 95% CI, 0.23%-6.76%) was not significantly different from that for AD (ER, 3.20%; 95% CI, 0.00%-7.20%; P = .91). For the patients with TAAAs, the rate of SCI after TEVAR with routine prophylactic CSFD was significantly lower than that with selective prophylactic CSFD (P = .04).

CONCLUSIONS

Our systematic review and meta-analysis has shown that SCI occurs more often after TEVAR for aortic aneurysms than for AD. Routine prophylactic CSFD, compared with selective CSFD, was associated with a lower rate of postoperative SCI after TEVAR for TAAAs. No significant association was found between the SCI rate and routine prophylactic CSFD for patients undergoing TEVAR for isolated TAA or AD.

CT of Postoperative Repair of the Ascending Aorta and Aortic Arch

While many of the classic open surgical repairs are still used to repair the ascending aorta, management of the aortic arch has become more complex via implementation of newer open surgical and endovascular techniques. Furthermore, techniques are often combined in novel repairs or to allow extended anatomic coverage. As such, a framework that rests on understanding the expected postoperative appearance is necessary for the diagnostic radiologist to best interpret CT studies in these patients. After reviewing the imaging appearances of the common components used in proximal aortic repair, the authors present a structured approach that focuses on the key relevant questions that diagnostic radiologists should consider when interpreting CT studies in these patients. For repair of the ascending aorta, this includes determining whether the aortic valve has been repaired, whether the sinuses of Valsalva have been repaired, and how the coronary arteries were managed, when necessary. In repairs that involve the aortic arch, the relevant considerations relate to management of the arch vessels and the distal extent of the repair. In focusing on these questions, the diagnostic radiologist will be able to identify and describe the vast majority of repairs. Understanding these questions will also facilitate improved understanding of novel repairs, which often use these basic building blocks. Finally, complications-which typically involve infection, noninfectious repair breakdown, hemorrhage, problems with endografts, or disease of the remaining adjacent aorta-will be identifiable as deviations from the expected postoperative appearance. Online supplemental material is available for this article. ^©RSNA, 2021.

The fate of the left subclavian artery in TEVAR for aortic arch pathology

BACKGROUND AND AIM OF STUDY

The origin of the vertebral artery (VA) from the left subclavian (LSA) is variable and must be considered when proximal ligation or embolization is performed post thoracic endovascular aortic repair (TEVAR) and extra-anatomical bypass (EAB). A retrospective study was conducted to understand the patency of the LSA and VAs after TEVAR and the relationship of the EAB to the LSA.

METHODS

Fifty-six patients underwent TEVAR where the LSA origin was occluded. A comparison was performed between the length of the proximal LSA from the arch of the aorta to the origin of the VA. Patient outcomes included posterior or anterior circulation cerebrovascular accident, spinal cord ischemia (SCI), and symptoms and signs of left arm ischemia (LAI). Thirty one underwent EAB with 8 undergoing occlusion of the LSA proximal to the origin of the left VA. A further 25 underwent TEVAR with no EAB performed. The mean (standard deviation) of origin of the VA from the origin at the arch was 37.0 (12.9) mm compared to 34.0 (13.7) mm in those where no bypass was performed (p 0.45). Four patients underwent intraluminal plug occlusion and four had external ligation of the proximal LSA in those undergoing EAB.

CONCLUSIONS

Careful evaluation of the LSA is needed when planning TEVAR as occlusion techniques may be dependent on a minimum length of the VA from the aortic arch. The mean length of the VA from the aorta has high heterogeneity which may dictate the optimum occlusion method for LSA.

Carotid-Carotid Transposition for Zone 1 Thoracic Endovascular Aortic Repair

OBJECTIVES

Carotid-carotid bypass is the standard technique for cervical aortic arch debranching to maintain left common carotid artery perfusion with zone I thoracic endovascular aortic repair (TEVAR), while left-to-right carotid-carotid transposition (CCT) has been described as an autologous alternative. We report on our center's experience with CCT in the setting of zone I TEVAR. This is the only published series of this technique.

METHODS

All patients who underwent CCT, defined by CPT code 35509, between 2017 and 2020 were identified at our tertiary care center. Patient demographics, indications for CCT, complications specific to CCT, operative details, post-operative course, and outcomes were retrospectively reviewed.

RESULTS

A total of 13 patients underwent CCT prior to zone 1 TEVAR. The indications for intervention were thoracic or thoracoabdominal aortic aneurysms and dissections secondary to hypertension (n = 10), Marfan syndrome (n = 2), and Turner syndrome with aneurysmal degeneration of previous coarctation repair (n = 1). There was a high incidence of preexisting hypertension (92%), malnutrition (69%), and smoking (61%) in this cohort. Operative intervention was performed on both an elective (n = 7, 54%) and an urgent (n = 6, 46%) basis. Complications directly related to CCT included transient unilateral recurrent laryngeal nerve deficit (n = 1, 7.7%). There were no cerebrovascular events, surgical site infections, or procedure-related mortalities. All transpositions with follow-up imaging were patent without stenosis or thrombosis (average 7.2 months, n = 10). There were no late complications related to CCT.

CONCLUSIONS

CCT is a safe and autologous alternative to carotid-carotid bypass for left common carotid artery revascularization with zone I TEVAR.

When is extra-anatomical bypass for the left subclavian artery required to prevent ischaemia after thoracic endovascular stent grafting?

INTRODUCTION

Thoracic endovascular aortic repair (TEVAR) has become an accepted treatment for thoracic aortic disease. However, the principal complications relate to coverage of the thoracic aortic wall and deliberate occlusion of aortic branches over a potentially long segment. Complications include risk of stroke, spinal cord ischaemia (SCI) and arterial insufficiency to the left arm (left arm ischaemia (LAI)). This study specifically scrutinised the development of SCI and LAI after TEVAR for interventions for thoracic aortic disease from 1999 to 2020. In particular, those who underwent extra-anatomical bypass (both immediate and late) were compared to the length of thoracic aortic coverage by the stent graft.

MATERIALS AND METHODS

Ninety-eight patients underwent TEVAR. The presenting symptoms, pathology, procedural and follow-up data were collected prospectively with particular evidence of stroke, SCI and LAI both immediate onset and after 48 h of graft placement.

RESULTS

Fifty underwent TEVAR for an aneurysm (thoracoabdominal aortic aneurysm), 22 for dissection, 19 for acute transection and 7 for intramural haematoma/pseudoaneurysm of the thoracic aorta. Twenty-nine (30%) required a debranching procedure to increase the proximal landing zone (1 aorto-carotid subclavian bypass, 10 carotid/carotid subclavian bypass and 18 carotid/subclavian bypass). Ten patients (10%) died within 30 days of TEVAR. Twenty-four grafts covered the left subclavian artery origin without a carotid/subclavian bypass. Five required a delayed carotid/subclavian bypass for LAI (4) and SCI (1). Six developed immediate signs of SCI after TEVAR and these 11 (group i) had a mean (SD) length of coverage of the thoracic aorta of 30.2 (10.6) cm compared to 21.5 (11.2) cm (group g) in those who had no LAI or SCI post TEVAR, p < 0.05.

CONCLUSIONS

In this series, delayed carotid/subclavian bypass may be required for chronic arm ischaemia and less so for SCI. The length of coverage of thoracic aorta during TEVAR is a factor in the development of delayed SCI and LAI occurrence. Carotid subclavian bypass is required for certain patients undergoing TEVAR (particularly if greater than 20 cm of thoracic aorta is covered).

Aortic arch aneurysm repair - Unsteady hemodynamics and perfusion at different heart rates

The aortic arch aneurysm is a complex disease that requires branching of one or more aortic arch vessels and can be fatal if left untreated. In this in vitro study, we examine the effect of the treatment approach on the unsteady hemodynamics and blood perfusion to the upper vessel's in models of an aortic arch aneurysm, and of the three common repair approaches: open-chest surgical repair, chimney, and hybrid approach. A particle image velocimetry method was used to quantify the unsteady hemodynamics in the four models simulated in a mock circulatory loop, to evaluate unsteady hemodynamic parameters and measure perfusion to the brain and the upper body. According to the findings, in terms of perfusion to the brain and upper body, the surgery model has the highest flow rate comparing to the other models in most heart-rate conditions. It also shows oscillatory parameters in the upper vessels which in normal arteries are correlated with a better arterial function. Between the two endovascular procedures, the hybrid model exhibits slightly better hemodynamic characteristics than the chimney model, with lower shear stresses and more oscillatory flow and WSS in the upper vessels. The hybrid model had lower perfusion flow rates to upper vessels during rest conditions (90BPM). However, unlike the other models, perfusion in the hybrid model increased with heart rate, thus at 135 BPM, it results in flow rate to upper vessels similar to that of the chimney model. The results of this study may shed light on future endograft' design and placement techniques.

Endovascular aortic repairs combined with looping-chimney technique for repairing aortic arch lesions and reconstructing left common carotid artery

Background

The aim of this retrospective study was to evaluate the feasibility and efficacy of thoracic endovascular aortic repairs (TEVAR) combined with looping chimney technique (LCT) for repairing aortic arch lesions and reconstructing left common carotid artery.

Methods

Total of 14 patients (mean age 52.86±14.46 years; range, 27–79; 10 men, 4 women) were included in the study from December 2016 to December 2018. Aortic arch pathologies of all patients with insufficient proximal landing zone (PLZ) were repaired by TEVAR under local anesthesia, before TEVAR, the left common carotid artery (LCCA) was protected by the guiding sheath from the retrograde brachial access, after aortic stent graft deployed, chimney graft was implanted to restore LCCA by LCT if necessary. All patients underwent computed tomography angiograph (CTA) 2 weeks, 3 months, 6 months and 1 year after surgery.

Results

Pathology results of 14 patients included: type B aortic dissection (n=8), penetrating aortic ulcers (n=1), retrograde type A aortic dissection (n=1), thoracic aortic aneurysm (TAA) (n=2), and thoracic aortic pseudoaneurysm (n=2). In all patients, aortic arch lesions were repaired by TEVAR; while LCCA were successfully reconstructed by the LCT. In one case, the innominate artery (IA) was simultaneously reconstructed through the same percutaneous right brachial artery (RBA) access. Coiling eliminated type Ia endoleak in 3 patients, and type II endoleak vanished by plugging left subclavian artery (LSA) in 2 patients. In four patients, the chimney stent (CG) of LCCA was partially compressed and then another bare stent was implanted to restore patency rate. The mean follow-up duration was 9.77±6.64 months (range, 0–24) and no combinations were observed in 13 patients; except in one patient who died of cerebral hemorrhage due to abnormal coagulation function.

Conclusions

TEVAR combined with LCT has shown to be suitable surgical approach for aortic arch lesions. Either covered intentionally or inadvertently, the LCCA could be safely and effectively reconstructed via percutaneous RBA access. Short-term follow-up demonstrated satisfactory morbidity and mortality in high-risk patients; however, longer follow-up is required to assess the effectiveness and durability of this innovative endovascular procedure.

Off pump hybrid extra-anatomic techniques for aortic arch repair-own experience

Background

Treatment of the aortic arch pathologies is technically challenging. In this study we assess early and late outcomes of hybrid aortic arch repairs that comprise extra-anatomic surgical procedures completed by thoracic endovascular interventions [thoracic endovascular aortic repair (TEVAR)].

Methods

Since 2007, 21 patients (8 women and 13 men) with a median age of 48 years have undergone hybrid procedures for aortic arch pathologies. All of them were treated without cardio-pulmonary bypass. All survivors were followed up regularly and imaging examination were performed. A technical success, procedural complications as well as the early and late mortality and morbidity rates were evaluated.

Results

All patients survived surgery and TEVAR was technically successful in all of them. However, 2 individuals died (in-hospital mortality rate 9.5%) during in-hospital stay, both due to multi-organ failure (MOF). Additionally, one patient developed symptoms of cerebral stroke, another one of spinal cord ischemia. During the follow-up that ranged from 6 to 118 months and was completed by 100% of the survivors, one patient died 3 years after procedure because of sepsis (aorto-oesophageal fistula prior to intervention) and late vascular graft occlusions were noted in three cases.

Conclusions

Hybrid procedures on the aortic arch that comprise surgical and endovascular interventions has become an attractive and safe therapeutic option with acceptable mortality and morbidity rate. They may be considered as a method of choice in treatment of the elderly and high-risk patients.

Transposition of the left vertebral artery during endovascular stent-graft repair of the aortic arch

OBJECTIVES

The aim of this study was to present our experience with the management of isolated left vertebral artery during hybrid aortic arch repairs with thoracic endovascular aortic repair completion.

METHODS

This is a single-center, observational, cohort study. Between January 2007 and December 2018, 9 patients (4.5%) of 200 who underwent thoracic endovascular aortic repair were identified with isolated left vertebral artery. The isolated left vertebral artery was the dominant vertebral artery in 4 cases and entered the Circle of Willis to form the basilar artery in all cases. Isolated left vertebral artery transposition was performed in 2 patients during open ascending/arch repair before thoracic endovascular aortic repair completion. In 4 patients, isolated left vertebral artery transposition was performed concomitant with carotid-subclavian bypass during thoracic endovascular aortic repair completion ("zone 2" thoracic endovascular aortic repair). Primary outcomes were early (<30 days) and late survival, freedom from aortic-related mortality, and isolated left vertebral artery patency.

RESULTS

Primary technical success was achieved in all cases. Isolated left vertebral artery-related complication occurred in 1 patient (Horner syndrome). Immediate thrombosis, vagus/recurrent laryngeal nerve palsy, lymphocele, and chylothorax were never observed. Postoperative cerebrovascular accident or spinal cord injury was not observed. Median follow-up was 15 months (range, 3-72). We did not observe aortic-related mortality during the follow-up. Aortic-related intervention was never required. Both isolated left vertebral artery and carotid-subclavian bypass are still patent in all patients with no sign of anastomotic pseudoaneurysm or stenosis.

CONCLUSIONS

Although isolated left vertebral artery is not a frequent occurrence, it is not so rare. It may pose additional difficulties during hybrid aortic arch surgical repairs, but isolated left vertebral artery transposition was feasible, safe, and a durable reconstruction.

Endovascular treatment of complex diseases of the thoracic aorta-10 years single centre experience

BACKGROUND

Introduction of invasive endovascular techniques constituted a real a breakthrough in the treatment of aortic aneurysm dissection and rupture. We assessed the effectiveness and safety of thoracic endovascular aortic repair (TEVAR) in patients with thoracic aortic pathologies.

METHODS

Between 2007 and 2017, 118 patients with thoracic aortic pathology underwent TEVAR. Among them, 20 (16.9%) patients required hybrid procedures. Stent grafts indication were thoracic aortic aneurysm in 46 (39.0%) patients, type B dissection in 68 (57.6%) patients and other indications in 4 (3.3%). Procedural success rate, in-hospital and late mortality and morbidity were evaluated.

RESULTS

The patients were followed-up for a mean of 55 months (range, 6-118 months). The technical success rate was 96%. Five patients died during the first 30 days after procedure (mortality 4.2%), four due to ischemic stroke followed by multi-organ failure and another one hemodynamically significant type I endoleak. Most of them were noted in the first years of our study. Five others died during post-discharged period. Four patients developed neurological complications, including stroke (n=2; 1.7%) and paraparesis (n=2; 1.7%). There were 6 (5.1%) primary (5 type I and 1 type II) and 3 (2.5%) secondary endoleaks (1 type I and 2 type III). Secondary interventions were required in 8 subjects. There was one case of stent collapse and two retrograde aortic dissection.

CONCLUSIONS

Treatment of descending aortic diseases by using stent graft implantation has become the method of choice, decreasing the risk of open surgery, especially in patients with severe clinical state and comorbidities. However, effectiveness and safety may be achieved by experience team.

Clinical Application of an Original Flexible MK Stent-Graft for Nonruptured Thoracic Aortic Aneurysms: Early Experience

Objective

To obtain early MK stent-grafting results for nonruptured thoracic aortic aneurysms and thoracoabdominal aortic aneurysms.

Methods

The authors analyzed 47 patients who underwent treatment using MK stent-grafting. All patients (40 men and 7 women; mean age, 70.8 years) underwent elective procedures. Straight, curved, or tapered MK stents were constructed from a nitinol wire and covered with seamless, cylindrical woven polyester fabric grafts. The mean stent-graft diameter was 24 to 48 mm. In cases where the aneurysm had a short proximal neck (under 15 mm), supraaortic arch artery bypass surgery was planned to lengthen the neck.

Results

Simple stent-grafting without bypass was performed in 26 patients, whereas stent-grafting with supraaortic arch artery bypass was performed in 21 patients. An 18 or 20 F sheath was used as the delivery system in 46 patients (96%). In all 47 patients, the stent-grafts were successfully deployed. Two patients died while in hospital, and another 2 patients suffered a stroke. No other perioperative complications were observed. Postoperative computed tomography after 3 months showed complete thrombus formation in 42 patients (93.3%; 42/45 patients).

Conclusions

Forty-seven patients with thoracic aortic aneurysm were treated with our original flexible MK stent-graft system. Using a small sheath system, straight or curved M-K stent-grafts could be deployed to adequately fit to the aorta as planned. Furthermore, simultaneous bypass surgery widened the application of stent-grafting. However, careful long-term observation is necessary, and further studies are needed to assess such stent-grafting with bypass surgery.

Application of thoracic endovascular aortic repair (TEVAR) in treating dwarfism with Stanford B aortic dissection: A case report

RATIONALE

To apply thoracic endovascular aortic repair (TEVAR) to treat dwarfism complicated with Stanford B aortic dissection.

PATIENT CONCERNS

In this report, we presented a 63-year-old male patient of dwarfism complicated with Stanford B aortic dissection successfully treated with TEVAR.

DIAGNOSES

He was diagnosed with dwarfism complicated with Stanford B aortic dissection.

INTERVENTIONS

After conservative treatment, the male patient underwent TEVAR at 1 week after hospitalization. After operation, he presented with numbness and weakness of his bilateral lower extremities, and these symptoms were significantly mitigated after effective treatment. At 1- and 3-week after TEVAR, the aorta status was maintained stable and restored.

OUTCOMES

The patient obtained favorable clinical prognosis and was smoothly discharged. During subsequent follow-up, he remained physically stable.

LESSONS

TEVAR is probably an option for treating dwarfism complicated with Stanford B aortic dissection, which remains to be validated by subsequent studies with larger sample size.

Post-traumatic acute thoracic aortic injury (TAI)-a single center experience

Background

We assess the effectiveness and our experience in emergency thoracic endovascular aortic repair (TEVAR) in patients with post-traumatic acute thoracic aortic injury (TAI) and associated multiorgan trauma. TAI is a life-threatening condition. It usually results from a sudden deceleration caused by vehicle accident, a fall or some other misfortune. Techniques of endovascular aortic repair have become promising methods to treat emergent TAI.

Methods

Since 2007, 114 patients with thoracic aorta pathologies have been treated by TEVAR. Our study involved 15 (incl. 14 men) of them (13%) who underwent stent graft implantation for post-traumatic either aortic rupture or pseudoaneurysm. The procedural access was limited to small skin incision in one groin and percutaneous puncture of the contralateral femoral artery. We evaluated technical success, early and long-term mortality, complication rate of procedure and throughout clinical and instrumental follow-up.

Results

Technical success rate was 100%. All patients survived the endovascular interventions. No additional procedures or conversions to open surgery were necessary. After the operation, none of the patients had symptoms of stroke or spinal cord ischemia (SCI). No serious stent-graft-related adverse events such as endoleak, infection or migration were noted during follow-up period that ranged from 6 to 108 months.

Conclusions

In our department, techniques of TEVAR with stentgraft implantation have become methods of choice in treatment of traumatic TAIs since they have enabled to minimize operational risk, particularly in unstable multitrauma patients in severe clinical status. TEVAR for TAI performed in emergency settings provide favorable long-term results.

Stent-Graft Placement in Atherosclerotic Descending Thoracic Aortic Aneurysms: Midterm Results

Purpose:

To determine midterm durability and need for reinterventions after stent-graft placement in atherosclerotic descending thoracic aortic aneurysms.

Methods:

Fifty-four patients (38 men; mean age 68 years, range 33–87) underwent stent-graft repair of chronic atherosclerotic aneurysms of the descending thoracic aorta between November 1996 and December 2002. Acute aortic syndromes (type B aortic dissections, perforating ulcers, and traumatic dissections) were excluded from analysis. Two types of commercially available stent-grafts were used (Talent and Excluder).

Results:

The primary technical success rate was 94.4%. In-hospital mortality was 3.7% (2/54). No adverse neurological events were encountered. Of 3 (5.6%) early type I endoleaks, 2 (3.7%) required reintervention; the other type I endoleak closed spontaneously. Mean follow-up was 38 months (range 1–72) in the 52 surviving patients. Four (7.7%) type I, 7 (13.5%) type II, and 4 (7.7%) type III endoleaks were seen. Three 3 patients had additional treatment for endoleaks (proximal stenting [type Ia], open thoracoabdominal repair [type Ib], and embolization [type II]). Two of the 3 reinterventions were performed in the first year of follow-up. One additional patient with a type Ia endoleak not suitable for reintervention is under close observation. There were no differences in the number of endoleaks between the 2 types of stent-grafts. Three-year event-free survival was 63%.

Conclusions:

Midterm durability of endovascular stent-graft placement in atherosclerotic descending aortic aneurysms seems promising, as the rate of endoleaks requiring reintervention is acceptably low. In our series, endoleak formation occurred during the first year after stent-graft placement, so close follow-up of patients after aortic aneurysm repair is crucial. Further studies are warranted to evaluate long-term durability of this new treatment modality.

A Decade of Thoracic Endografting: Planning the Next 10 Years…

Endovascular repair has emerged as a very important treatment modality in the management of a host of serious and relatively frequent thoracic aortic diseases. This minimally invasive approach is certain to revolutionize the entire field of thoracic aortic surgery in the near future. The technologies, however, can still be considered as a “work in progress.” Future refinements, which should be available within the next 1 to 2 years, will address some of the most important needs as yet unmet today: lower profile (<22 F) delivery systems, greater device flexibility, no longitudinal metal bars, and precise deliverability and deployment characteristics that will be conducive to optimal success and safety, especially in the region of the aortic arch.

Endografting of the Aortic Arch

In recent years, endovascular repair with stent-grafts has made great advances as a minimally invasive alternative to conventional open surgery in the treatment of aortic aneurysm and dissection. Although many commercial endograft systems are now used worldwide for the treatment of these pathologies in the abdominal aorta, only a few dedicated stent-grafts have been developed for use in the thoracic aorta. However, these second-generation commercial endografts have almost identical specifications and performance profiles in terms of structure, function, and delivery mechanism as stent-graft systems employed in the abdominal aorta. Thus, endografts have been used in the thoracic aorta with little consideration to the morphological and hemodynamic characteristics specific to the aortic arch and the deployment techniques needed to navigate this curved region of the thoracic aorta. This review will survey the literature on aortic arch stent-graft repair and identify key elements critical to the successful design of an endograft to treat lesions in the aortic arch.

Techniques for Preserving Vertebral Artery Perfusion During Thoracic Aortic Stent Grafting Requiring Aortic Arch Landing

Thoracic endografting offers many advantages over open repair. However, delivery of the device can be difficult and may necessitate adjunctive procedures. We describe our techniques for preserving perfusion to the left subclavian artery despite endograft coverage to obtain a proximal seal zone. We reviewed our experience with the Talent thoracic stent graft (Medtronic, Santa Rosa, CA). From 1999 to 2003, 49 patients received this device (29 men, 20 women). Seventeen patients required adjunctive procedures to facilitate proximal graft placement. We performed left subclavian-to-left common carotid artery transposition (6), left common carotid-to-left subclavian artery bypass with ligation proximal to the vertebral artery (7), and left common carotid-to-left subclavian artery bypass with proximal coil embolization (4). Patients who had anatomy unfavorable to transposition or bypass with proximal ligation (large aneurysms or proximal vertebral artery origin) were treated with coil embolization of the proximal left subclavian artery in order to prevent subsequent type II endoleaks. Technical success rate of the carotid subclavian bypass was 100%. Patient follow-up ranged from 3 to 48 months with a mean of 12 months. Six patients had follow-up <6 months owing to recent graft placement. Primary patency was 100%. No neurologic events occurred during the procedure or upon follow-up. One patient had a transient chyle leak that spontaneously resolved in 24 hours. Another patient had a phrenic nerve paresis that resolved after 3 weeks. We believe that it is important to maintain patency of the vertebral artery specifically when a patent right vertebral system and an intact basilar artery is not demonstrated. Furthermore, we describe a novel technique of coil embolization of the proximal left subclavian artery in conjunction with left common carotid-to-left subclavian artery bypass. This circumvents the need for potentially hazardous mediastinal dissection and ligation of the proximal left subclavian artery in cases of large proximal aneurysms or unfavorable vertebral artery anatomy.

Endovascular Repair of Cervical Aortic Arch Aneurysm

Cervical aortic arch (CAA) is a rare congenital anomaly of the aortic arch. Rarely, CAA is associated with aneurysm of the arch and great vessels. A 32-year-old male patient, previously in good health, presented with 2 weeks of severe chest pain. Radiographic evaluation revealed a CAA with aneurysmal dilation of the distal aortic arch. The aneurysm extended into the left subclavian artery. There was also marked angulation just distal to the aneurysmal portion. The aneurysmal arch and subclavian artery were repaired using a thoracic aortic endograft. An open axillary-to-axillary bypass was performed, and the left axillary artery was ligated proximally. This restored perfusion to the left upper extremity and effectively excluded the aneurysm sac. Immediately postoperatively, the patient's chest pain resolved, and he has remained symptom free. To the authors' knowledge, this is the first reported repair of a cervical arch aneurysm by endovascular technique.

Endoluminal Repair of a Thoracic Arch Aneurysm Using a Scallop-Edged Stent-Graft

Purpose:

To report a new technique of endoluminal thoracic aortic arch aneurysm repair using a scalloped stent-graft.

Case Report:

A 79-year-old man presented with a 7.5-cm thoracic aneurysm involving the inner curve of the aortic arch. Endoluminal repair was performed with a scalloped stent-graft that allowed perfusion of the brachiocephalic (innominate) artery. Preliminary extra-anatomical left common carotid and subclavian artery bypass grafting had been performed to allow coverage of the origins of these vessels.

Conclusions:

The use of fenestrated endoluminal grafts in the aortic arch can be achieved safely and may increase the treatment options for the high-risk patient.

Results of Thoracic Endovascular Grafting in Different Aortic Segments

Purpose:

To compare the results of thoracic endovascular grafting of different aortic segments performed with commercially available stent-grafts.

Methods:

Between January 1999 and October 2006, 178 patients (150 men; mean age 69.4±10.2 years) underwent endovascular grafting of the thoracic aorta (68 hybrid procedures) with commercially produced stent-grafts from 4 manufacturers. Patients were divided into 3 groups according to the aortic segment involved: 64 aortic arch cases (37 hybrids for supra-aortic trunks revascularization), 100 descending thoracic aorta (DTA) cases (17 hybrid: 12 for access and 5 for associated abdominal aortic aneurysm), and 14 thoracoabdominal aorta (TaA) patients excluded from conventional repair (14 hybrids for renal and splanchnic revascularization).

Results:

The technical success was 93.8% (167/178). Overall 30-day mortality was 5.6% (10/178). There were 10 (5.6%) type I endoleaks. Initial clinical success was 88.2% (157/178). At a mean follow-up of 29.3±21.2 months, the midterm clinical success was 89.9% (160/178). In the arch group, the technical success was 85.9% (55/64). Thirty-day mortality was 6.3% (4/64). There were 8 (12.5%) type I endoleaks. Initial and midterm clinical success rates were 79.7% (51/64) and 85.9% (55/64), respectively. In the 100-patient DTA group, the technical success was 98.0%. Thirty-day mortality was 2.0%. The type I endoleak rate was 2.0%. Clinical success was 96.0% initially and 95.0% at midterm. All 14 of the TaA cases were completed successfully, but 30-day mortality was 28.6% (4/14). There were no type I endoleaks. Clinical success rates initially and at midterm were both 71.4% (10/14).

Conclusion:

Over the last 6 years, synergy between endovascular and surgical procedures allowed treatment of all segments of the thoracic aorta. Overall perioperative and medium-term results were reasonably favorable; however, they were more satisfactory when the descending thoracic aorta alone was involved. Hybrid procedures allowed treatment of all aortic segments, but they decreased the success rates significantly. Endovascular grafting is currently our preferred method of treating pathologies involving the DTA and aortic arch, while our data suggest limiting the use of stent-grafts to high-risk patients or compassionate indications when the thoracoabdominal aorta is involved.

Thoracic Stent Grafts with a Distal Fenestration for the Celiac Axis

Descending thoracic aneurysms can be treated with a stent graft provided that there is sufficient proximal and distal aortic neck length above the celiac axis. One of the options for the treatment of thoracic aneurysms with a too short distal neck is described in this report. For this purpose, a stent graft was constructed with a scallop for the celiac axis. Three cases are presented, and the technical details are described.

Aortic Arch Aneurysm and Patent Left Internal Mammary Artery: Technique of Transposition of Supra-aortic Vessels and Embolization of the Subclavian Artery

Endovascular treatment of aortic arch aneurysms poses unique problems because of vascularization of the carotid arteries.

Transposition of supra-aortic vessels is becoming an established and accepted strategy for expanding the applicability of stent graft repair. left subclavian artery (LSA) is not usually transposed because its overstenting does not produce relevant complications. Nevertheless, some selected cases need high-pressure revascularization of the LSA, such as in the presence of a patent left internal mammary artery. We present a technique of revascularization of supra-aortic vessels and “balloon protected” embolization of the origin of the LSA.

Aortic Arch and Descending Thoracic Aortic Aneurysms: Experience with Stent Grafting for Second-Stage “Elephant Trunk” Repair

Reconstruction of aortic arch and descending thoracic aortic aneurysms (TAAs) is technically challenging and associated with significant morbidity and mortality. We report our experience with extensive TAAs using a two-stage “elephant trunk” repair, with the second stage completed using an endovascular stent graft (ESG). Over 6 years, 111 patients underwent ESG treatment of TAAs at Mount Sinai Medical Center. Twelve of these patients were referred for ESG placement for the second stage of elephant trunk reconstruction because comorbidities placed them at high risk of open surgical repair. Our database was analyzed for technical and clinical success and perioperative complications. The mean follow-up was 11.8 months (range 1–64 months). Twelve patients (five women and seven men) with a mean age of 69 ± 10 years underwent repair of their distal aortic arch and descending TAAs. These aneurysms included nine atherosclerotic aneurysms, one pseudoaneurysm, and two penetrating atherosclerotic ulcers. Three patients were symptomatic. Stent graft repair was technically successful in 91.7% or 11 of 12 patients. Excessive aortic arch tortuosity resulted in failure to deploy a stent graft in one patient. An antegrade approach through the open elephant trunk was used in two patients with severe iliac occlusive disease. Endoleaks (type 2) were identified in two patients with no aneurysm expansion; however, a 14 mm expansion over 1 year occurred in a patient with no identifiable endoleak. One early mortality occurred in a patient with a ruptured 6 cm infrarenal AAA after successful exclusion of the 8 cm TAA. Second-stage elephant trunk reconstruction of an extensive TAA using an ESG is effective in the short term. Its long-term durability remains to be determined.

An In Vitro Phantom Study on the Role of the Bird-Beak Configuration in Endograft Infolding in the Aortic Arch

Purpose: To assess endograft infolding for excessive bird-beak configurations in the aortic arch in relation to hemodynamic variables by quantifying device displacement and rotation of oversized stent-grafts deployed in a phantom model. Methods: A patient-specific, compliant, phantom pulsatile flow model was reconstructed from a patient who presented with collapse of a Gore TAG thoracic endoprosthesis. Device infolding was measured under different flow and pressure conditions for 3 protrusion extensions (13, 19, and 24 mm) of the bird-beak configuration resulting from 2 TAG endografts with oversizing of 11% and 45%, respectively. Results: The bird-beak configuration with the greatest protrusion extension exhibited the maximum TAG device displacement (1.66 mm), while the lowest protrusion extension configuration led to the minimum amount of both displacement and rotation parameters (0.25 mm and 0.6°, respectively). A positive relationship was found between the infolding parameters and the flow circulating in the aorta and left subclavian artery. Similarly, TAG device displacement was positively and significantly (p<0.05) correlated with the pulse pressure for all bird-beak configurations and device sizes. However, no collapse was observed under chronic perfusion testing maintained for 30 days and pulse pressure of 100 mm Hg. Conclusion: These findings suggest that endograft infolding depends primarily on the amount of aortic pulsatility and flow rate and that physiological flows do not necessarily engender hemodynamic loads on the proximal bird-beak segment sufficient to cause TAG collapse. Hemodynamic variables may allow for identification of patients at high risk of endograft infolding and help guide preventive intervention to avert its occurrence.

Meningeal haemorrhage secondary to cerebrospinal fluid drainage during thoracic endovascular aortic repair

Thoracic endovascular aortic repair (TEVAR) has shown lower mortality compared with open surgical repair (OSR). However, the risk of spinal cord ischaemia (SCI) remains similar than OSR. As a prophylactic measure to reduce the risk of SCI, cerebrospinal fluid (CSF) drainage has been widely used in OSR. In TEVAR, the utility of this adjunct is still controversial. We report a case of a 56-year-old man referred for TEVAR for a descending thoracic aneurysm that previously underwent an abdominal aneurysmectomy with aortobifemoral bypass graft. On the day before, a lumbar cerebrospinal drain was placed prophylactically. Forty-eight hours after the procedure, meningeal symptoms without neurological deficits developed. Clinical investigation revealed meningeal haemorrhage. Therapy with nimodipine was initiated with symptomatic relief. Evidence from randomized controlled trials supporting the role of CSF drainage in TEVAR is still lacking. We discuss the current recommendations, potential benefits and risks and cautions associated with CSF drainage in TEVAR.

Multibranched Frozen Elephant Trunk with Left Subclavian Artery Cannulation

Patients with aortic pathology involving the ascending aorta, the arch, and the descending aorta present a complex surgical challenge. A one-step hybrid procedure with ascending aorta repair, arch debranching, and frozen elephant trunk is reported in five patients. Left subclavian artery side graft cannulation is used to perfuse the spinal cord during circulatory arrest time.

Spinal cord ischemia after simultaneous and sequential treatment of multilevel aortic disease

OBJECTIVES

The aim of the present study is to report a risk analysis for spinal cord injury in a recent cohort of patients with simultaneous and sequential treatment of multilevel aortic disease.

METHODS

We performed a multicenter study with a retrospective data analysis. Simultaneous treatment refers to descending thoracic and infrarenal aortic lesions treated during the same operation, and sequential treatment refers to separate operations. All descending replacements were managed with endovascular repair.

RESULTS

Of 4320 patients, multilevel aortic disease was detected in 77 (1.8%). Simultaneous repair was performed in 32 patients (41.5%), and a sequential repair was performed in 45 patients (58.4%). Postoperative spinal cord injury developed in 6 patients (7.8%). At multivariable analysis, the distance of the distal aortic neck from the celiac trunk was the only independent predictor of postoperative spinal cord injury (odds ratio, 0.75; 95% confidence interval, 0.56-0.99; P=.046); open surgical repair of the abdominal aortic disease was associated with a higher risk of spinal cord injury but did not reach statistical significance (odds ratio, 0.16; 95% confidence interval, 0.02-1.06; P=.057). Actuarial survival estimates at 1, 2, and 5 years after the procedure were 80%±5%, 68%±6%, and 63%±7%, respectively. Spinal cord injury did not impair survival (P=.885).

CONCLUSIONS

In our experience, the risk of spinal cord injury is still substantial at 8% in patients with multilevel aortic disease. The distance of the distal landing zone from the celiac trunk is a significant predictor of spinal cord ischemia.

Hybrid arch debranching and proximal endograft extension to repair a type I endoleak after endovascular thoracic aneurysm repair

Endovascular repair of complex aortic disease has emerged over the past decade as an alternative to traditional open repair, especially for patients with significant medical comorbidities and/or anatomic challenges, such as reoperative fields. However, the possibility of graft migration and endoleak mandates long-term follow-up of these grafts. We present a patient who underwent hybrid repair after stent graft migration and proximal type I endoleak after thoracic endovascular aneurysm repair. This approach allowed us to avoid extensive surgery that would also necessitate circulatory arrest.

Coverage of the left subclavian artery without revascularization during thoracic endovascular repair is feasible: a prospective study

BACKGROUND

To effectively isolate thoracic aortic lesions in thoracic endovascular aortic repair (TEVAR), an adequate proximal landing zone length is required. The left subclavian artery (LSCA) and other branches of the aortic arch commonly impose limitations on proximal landing zone length, restricting the use of TEVAR. In this study, we investigated the outcomes of LSCA coverage during TEVAR.

METHODS

Between March 2009 and February 2010, we recruited patients with thoracic dissection, aneurysm or trauma from a single center for TEVAR. We categorized patients into 3 groups: full coverage, partial coverage, or noncoverage of the LSCA. We measured pre- and postoperative blood pressures and evaluated complications during follow-up.

RESULTS

We recruited 111 patients for our study: 55 (50%) and 25 (23%) patients had full and partial LSCA coverage, respectively. The upper left arm blood pressures before and after the operations were significantly different between the full-coverage group and the other groups (P < 0.0001). Follow-up occurred between 6 and 20 months, and the mean follow-up time was 10.4 months. Thirteen patients (24%) in the full-coverage group and 2 patients (8%) in the partial-coverage group suffered from simple vertebrobasilar ischemia (VBI). Eleven of the patients with VBI (20%) in the full-coverage group and 2 (8%) patients with VBI in the partial-coverage group had left subclavian steal syndrome at follow-up. No paraplegia or stroke was observed.

CONCLUSIONS

Intentional coverage of the LSCA to obtain an adequate proximal landing zone for TEVAR can be a treatment option for thoracic aortic lesions, although some patients experienced mil complications.

The role of multidetector computed tomography coronary angiography in imaging complications post-cardiac surgery

There have been numerous advances in the field of cardiac imaging. The advent of multidetector computed tomography coronary angiography (MDCT-CA) and in particular electrocardiographic (ECG)-gated acquisition has revolutionized the investigation of the complete spectrum of complications of common cardiothoracic surgical procedures. Generic complications, such as mediastinitis, pericardial effusion, sternal osteomyelitis, and mediastinal fibrosis, are discussed with illustrative examples of multiplanar and volume-rendered three-dimensional reconstructions. Graft-related complications of both coronary artery bypass grafts and aortic root grafts are reviewed. The role of MDCT-CA in the investigation of prosthetic valve endocarditis and root abscesses is outlined. We present a complete illustration of the detailed images that are obtained when investigating a full range of graft-related complications from both aortic and coronary surgery using ECG-gated MDCT-CA. MDCT-CA has the potential to become established as the optimal technique with which to image a multitude of complications post-cardiac surgery.