New Technique for Expanding the Proximal Landing Zone in Thoracic Endovascular Aneurysm Repair: Case Report

ABSTRACT

A thoracic aortic aneurysm is a dilatation in the wall of the aorta. If untreated, it can rupture or tear, which is life‐threatening. A 74‐year‐old man was admitted to Sina Hospital with hoarseness and dysphonia. He was diagnosed with a thoracic aortic aneurysm (TAA) measuring 73 mm near the left subclavian artery and a 46 mm saccular ulcerous TAA in the mid‐thoracic aorta. Preoperative evaluations were normal. Due to comorbidities, open surgery was not an option, so the patient was selected for thoracic endovascular aneurysm repair (TEVAR). However, the proximity of the aneurysm to the origins of the left subclavian and common carotid arteries limited the stent's landing zone. To resolve this, an open surgery was performed to ligate the left subclavian and common carotid arteries and bypass them to their right counterparts, extending the landing zone for the stent. TEVAR was then successfully carried out from the brachiocephalic trunk, covering most of the ulcerous TAA in the mid‐aorta. The patient was discharged in good condition and has shown positive progress in follow‐up visits. This case demonstrates a novel and complex approach that combines open surgical ligation and bypass of the left subclavian and common carotid arteries with TEVAR. The technique successfully expands the proximal landing zone for thoracic aortic aneurysm repair, contributing a practical solution for high‐risk patients with complex anatomy, leading to effective stent deployment and enhanced clinical outcomes.

Summary.

• This case shows a new complex approach combining open surgical ligation and bypass of the left subclavian and common carotid arteries with TEVAR that successfully expands the proximal landing zone for thoracic aortic aneurysm repair, contributing a practical solution for high‐risk patients with complex anatomy, leading to effective stent deployment and enhanced clinical outcomes.

1. Introduction

Aortic aneurysms involving the proximal ascending aorta are primarily caused by continuous biomechanical forces from pulsatile blood flow and structural weakening of the aortic wall due to genetic and environmental factors [1]. Thoracic aortic aneurysms (TAA) often develop slowly and are usually asymptomatic, making them difficult to diagnose. Some aneurysms never rupture. Many start small and stay small, although some grow over time. It is difficult to predict how quickly an aortic aneurysm may grow. For this reason, Individuals at risk should be screened for aneurysms using ultrasound or a CT scan to detect the condition before it causes serious complications [2, 3].

Given the asymptomatic nature of aortic aneurysm and the severe consequences of not diagnosing it, it is necessary to screen people at risk for this disease. Aortic ultrasound makes early detection and timely repair possible when the complication risk threshold is met, providing promising prospects for the treatment of this condition. Current Indications/Risk factors for screening: Any family history of aortic aneurysm, all smokers over 65 years of age, whether they have quit or continue to smoke [4, 5]. If the initial tests reveal an enlarged aortic size, additional CT scans or MRI tests are required. A Definitive diagnosis of the disease and determination of aortic size are made by performing a CT angiography of the aorta or an MRI. In principle, performing a CT scan for initial diagnosis is better. People with an enlarged aorta should undergo CT scans every 1–6 months, depending on their underlying condition and the initial size of the aorta, to assess both the size of the aorta and the rate of disease progression. Rapid aneurysm growth (more than 5 mm per year or more than 3 mm in 6 months) is an Indication for intervention and aortic repair [6, 7].

Thoracic aortic aneurysms can be treated in three ways, each offering a unique approach. In the open surgical method, the enlarged part of the aorta is removed using surgical incisions, and its site is repaired using grafts and artificial veins. Most cases of ascending aortic and aortic arch diseases are repaired in this way. In the stent graft method, the aneurysm site is repaired without the need for deep anesthesia, using angiographic equipment and methods that involve special stents covered with layers of Dacron. The hybrid or combined method, however, offers a versatile approach, providing a range of treatment options for different cases and ensuring that the patients are well informed about the available choices [8, 9, 10, 11].

The present study is a detailed review of a thoracic aortic aneurysm that was repaired via Thoracic Endovascular Aortic Repair (TEVAR) surgery. It aims to provide insights into this specific treatment method.

2. Case Presentation

2.1. History of Presenting Illness /Physical Examination

A 74‐year‐old man was admitted to Sina Hospital due to Hoarseness and dysphonia for a few months. The patient was a smoker with known hypertension and a history of coronary angiography. There was no significant family history. Vital signs were stable, and the physical examination of pulses, Extremities, Abdomen, and Cranial nerves was normal.

The differential diagnosis was laryngeal nodules, polyps, laryngitis, laryngopharyngeal reflux, vocal fold paralysis, and aneurysm.

2.2. Investigations

At first, laryngeal investigations were normal. He was diagnosed with a Thoracic Aortic Aneurysm with CT angiography (73 mm TAA, saccular, starting at the LSA/46 mm saccular ulcerous TAA in the mid‐thoracic aorta) (Table 1). He was admitted to the ward, and preoperative evaluations were done. The patient had a normal carotid duplex and brain MRI in preoperative evaluations.

TABLE 1.

Sizes of aorta.

4 cm ascending aorta	36 mm para‐celiac aortic diameter
73 mm TAA, saccular, starting at the LSA	32 mm para‐SMA aortic diameter
12 mm LZ to the LCA	SMA ostium is aneurysmal (20 mm in diameter)
21 mm LZ to the brachio‐cephalic trunk	32 mm infra renal aorta
31 mm aortic isthmus	17 mm R ulcerous CIA
46 mm saccular ulcerous TAA in the mid‐thoracic aorta	13 mm L CIA
46 mm saccular ulcerous TAA in the mid‐thoracic aorta	7–8 mm access vessels bilaterally
27 mm inferior thoracic aorta	14 mm R CFA, 10 mm L CFA

2.3. Treatment

Because of the patient's comorbidities (ischemic heart disease, low ejection fraction, and COPD), open surgery was not an option. Therefore, he was elected for TEVAR. The sac of an aneurysm was too close to the origin of the left subclavian and common carotid arteries. Accordingly, there was not enough space for the stent's landing zone. To expand it, an open surgery was performed. To preserve brain perfusion, the left subclavian and common carotid arteries were ligated and then bypassed to the right subclavian and common carotid arteries (Figure 1). Usually, the left subclavian and common carotids are bypassed to the right common carotid; but in this case, due to the risk of thrombosis, the left subclavian and common carotids were bypassed to their reciprocal arteries on the right side. With this change, the landing zone was prolonged, and we were able to place the stent from the origin of the innominate artery. TEVAR was done six days after the bypass from the brachiocephalic trunk with a 42‐38‐225 stent, which covered the majority of the ulcerous TAA in the mid‐segment of the aorta as well. He stayed 24 h in the ICU; then, after 2 days in the vascular surgery ward, he was discharged.

FIGURE 1.

The left subclavian and carotid bypass procedure.

2.4. Outcome and Follow‐Up

The patient was discharged in good condition after nine days and appeared well in follow‐up sessions (one, three, six, and twelve months with CT angiography and clinical assessment) (Figure 2).

FIGURE 2.

(A) Stent deployment 42‐38‐225. (B) Final graph. (C) One month follow‐up.

3. Discussion

Thoracic endovascular aortic repair (TEVAR) is an option to treat aortic dissections and descending aortic aneurysms. TEVAR is usually applied to patients with higher risks who are not suitable for open repair. TEVAR has been linked to lower mortality and morbidity rates, but cerebrovascular events are one of the most important complications [12]. Traditional TEVAR requires at least 2 cm of proximal and distal landing zones, but patients with aortic pathologies may lack a suitable proximal landing zone distal to the left subclavian artery (LSA). Proper evaluation and planning for the revascularization of arch vessels are essential when placing stent grafts in zones 0, 1, or 2 [13].

The Society of Vascular Surgery recognizes the lack of long‐term data on LSA management during TEVAR. Based on the best available evidence, the following recommendations are made: (1) For elective TEVAR requiring LSA coverage to achieve a proximal seal, routine preoperative revascularization is suggested (GRADE 2, level C). (2) Routine preoperative LSA revascularization is strongly advised for select patients with anatomy‐compromising blood flow to critical organs (GRADE 1, level C). (3) In urgent TEVAR cases for life‐threatening acute aortic syndromes, LSA revascularization should be individualized based on anatomy, urgency, and surgical expertise availability (GRADE 2, level C) [14].

In emergent cases, the LSA can be covered without revascularization; however, for patients with a left internal mammary artery (LIMA) graft or other specific conditions, LSA revascularization is crucial. Covering the LSA without revascularization can lead to complications such as upper extremity ischemia and spinal cord ischemia. In non‐urgent situations, elective LSA revascularization can improve outcomes and reduce morbidity. The EUROSTAR registry provides compelling evidence for routine LSA revascularization. It shows a significantly higher incidence of spinal cord injury or stroke, 8.4% in patients without LSA revascularization, compared to 0% in those who underwent revascularization (p = 0.49) [15]. Waterford et al. reported that the overall stroke rate associated with thoracic endovascular aortic repair (TEVAR) involving left subclavian artery (LSA) coverage without revascularization was 5.6%. In contrast, the stroke rate decreased to 3.1% during revascularization. Although this observed difference did not reach statistical significance, it is noteworthy that 26.2% of the strokes occurring after LSA coverage were in the posterior circulation. Of particular interest, only one patient who had undergone preoperative revascularization developed a stroke in this region. Consequently, the investigators concluded that routine revascularization of the LSA should be conducted in elective cases [12].

In cases where TEVAR lands in zone 2, there are two procedures to expand the landing zone: Left Carotid–Subclavian Artery Bypass [16] and Left Carotid–Subclavian Artery Transposition [17]. If the TEVAR lands in the first zone, Carotid–Carotid Crossover Bypass [18] or Subclavian–Subclavian and Axilloaxillary Artery Bypass [19] are the options for the expansion of the landing zone [13].

Ferrero et al. conducted a study with four patients in Zone 1 and 12 in Zone 2, achieving a 100% technical success rate for both groups. The Zone 1 cohort had no perioperative complications, while the Zone 2 cohort faced a 16.7% mortality rate, 0% stroke rate, and 8.4% spinal cord injury rate. Despite these risks, the investigators noted that hybrid procedures are a viable alternative to traditional open surgical repair [20].

A meta‐analysis by Moulakakis et al. reviewed 26 studies involving 820 patients who underwent aortic arch debranching. The analysis showed that zone 0 was involved in 41.7% of cases, zone 1 in 28.9%, and zone 2 in 29.4%, achieving a technical success rate of 92.8%. During a mean follow‐up of 22.1 months, endoleaks were seen in 16.6% of patients, and retrograde type A dissection occurred in 4.5%. Perioperative mortality was 11.9%, with stroke and spinal cord injury rates at 7.6% and 3.6%, respectively. The study concluded that aortic debranching offers high technical success and a relatively low mortality risk for patients deemed unfit for standard surgery [21].

The blockage of the left subclavian and common carotid artery can lead to neurological complications and cerebrovascular accidents due to ischemia. Hence, the revascularization of these arteries is essential [15]. To prevent CNS ischemia after TEVAR, a proper landing zone is required. Based on the pathology's extension and zone, the surgeon designed a plan. This case demonstrates a model of left subclavian to right subclavian and left carotid to proper carotid bypass, which are not standard procedures but effective and practical solutions that can provide reassurance and confidence in the face of complications.

4. Conclusions

This case exemplifies a significant procedure designed to expand the landing zone for Thoracic Endovascular Aneurysm Repair (TEVAR). The primary aim of this report is to enhance the understanding of procedures that can optimize the landing zone to achieve successful outcomes in TEVAR interventions. This objective will be accomplished through thoroughly elucidating the techniques employed in these procedures.

Author Contributions

Javad Salimi: project administration, supervision, writing – review and editing. Ghazal Dahaghin: data curation, writing – original draft. Siamak Mousazadeh: investigation, writing – review and editing. Afshin Bighamian: investigation, project administration, writing – review and editing.

Ethics Statement

The authors have nothing to report.

Consent

Written informed consent was obtained from the patient to publish this report in accordance with the journal's patient consent policy.

Conflicts of Interest

The authors declare no conflicts of interest.

Salimi J., Dahaghin G., Mousazadeh S., and Bighamian A., “New Technique for Expanding the Proximal Landing Zone in Thoracic Endovascular Aneurysm Repair: Case Report,” Clinical Case Reports 13, no. 10 (2025): e71339, 10.1002/ccr3.71339.

Data Availability Statement

All relevant data supporting the conclusions of this article are included within the article.