Emergency physician-modified endograft for ruptured thoracoabdominal aneurysms: Should renal preservation always be pursued?

Abstract

Fenestrated and branched endovascular devices have expanded the treatment options for complex aortic pathology, and physician-modified endografts (PMEGs) have emerged as a potential alternative for urgent repair. However, an important unresolved question is whether renal artery preservation should always be pursued during emergent repair. We report two cases of ruptured thoracoabdominal aneurysms treated with PMEGs at Hospital Geral Roberto Santos between January and February 2026. Based on computed tomography angiography, fenestrations were created using electrocautery and reinforced with a snare catheter loop, whereas directional branches were constructed using self-expanding covered stents. Both patients presented with ruptured Crawford type IV aneurysms and retroperitoneal hematomas. In the first case, a 26-year-old man underwent PMEG repair with preservation of the celiac trunk and superior mesenteric and right renal arteries, while the left renal artery was intentionally sacrificed. In the second case, a 68-year-old woman underwent repair with directional branches to the superior mesenteric artery and celiac trunk, without preservation of the renal arteries. Technical success was achieved in both cases; however, clinical outcomes differed substantially. Emergency repair of ruptured thoracoabdominal aneurysms using PMEGs is a feasible strategy when custom devices are unavailable. Although renal artery preservation remains an important objective, these two cases illustrate that intentional renal artery sacrifice may occasionally be unavoidable in critically unstable patients with unfavorable renal anatomy.

Thoracoabdominal aortic aneurysms represent one of the most challenging conditions in vascular surgery, with considerable morbidity and mortality rates reported even in experienced centers.^{[1, 2]} Open repair has historically been considered the standard treatment;^[3] however, its application in emergent settings is often limited by the physiological burden of thoracoabdominal exposure, prolonged visceral ischemia, and substantial blood loss.

In recent years, endovascular strategies have significantly expanded the therapeutic options for complex aortic pathology. Custom-made fenestrated and branched endografts have demonstrated favorable outcomes in the elective repair of thoracoabdominal aneurysms, allowing preservation of visceral perfusion while reducing the invasiveness of treatment.^{[4, 5, 6]} However, the major limitation of these devices in emergent situations is the manufacturing time required for custom fabrication, making them unsuitable for patients presenting with rupture.^[7]

In this context, physician-modified endografts (PMEGs) have emerged as an important alternative for urgent and emergent repair. This technique allows the rapid customization of commercially available stent grafts to incorporate fenestrations or branches for visceral vessels, enabling complex endovascular reconstruction without the delay associated with custom-made devices.^{[7, 8]}

Despite growing experience with PMEGs, several technical and strategic challenges remain unresolved. One of the most relevant dilemmas concerns the management of the renal arteries during emergent repair. In elective thoracoabdominal aneurysm repair, preservation of renal perfusion is widely considered a fundamental objective, as renal dysfunction has been consistently associated with increased mortality and poorer long-term survival following complex aortic interventions.^{[9, 10]} Consequently, most treatment strategies aim to maintain the patency of both renal arteries whenever technically feasible.

However, priorities may differ in the setting of ruptured aneurysms, where rapid hemorrhage control and maintenance of mesenteric perfusion are critical determinants of survival. Attempting to preserve the renal arteries in unfavorable anatomical conditions, such as small vessel diameter, severe angulation, or difficult catheterization, may significantly prolong the procedure and increase the risk of intraoperative instability.

Recent evidence evaluating renal artery coverage during emergent endovascular aneurysm repair (EVAR) supports the concept that renal preservation, although desirable, may not always be mandatory in critically unstable patients. Tanious et al.^[11] demonstrated that bilateral renal artery coverage during ruptured abdominal aortic aneurysm repair was associated with significantly increased mortality and dialysis rates, whereas unilateral renal artery coverage was not significantly associated with in-hospital mortality or 1-year survival. These findings suggest that selective renal artery sacrifice may represent an acceptable trade-off in specific emergent scenarios.

Therefore, whether renal preservation should always be pursued during emergent PMEG repair remains an undefined and clinically relevant question.

In this report, we describe two cases of ruptured thoracoabdominal aneurysms treated with PMEGs. Particular emphasis is placed on the intraoperative decision-making process regarding renal preservation and the potential role of procedural simplification in the management of these critically ill patients.

Methods/Case Series

This study was conducted under an institutional research protocol approved by the Research Ethics Committee of Hospital Geral Roberto Santos (CEP/HGRS), CAAE no: 76303923.4.0000.5028, with ethical approval granted on December 13, 2023. The protocol was designed to evaluate the treatment of aortic aneurysms using PMEGs based on the Hercules® endograft platform.

We report two consecutive cases of ruptured thoracoabdominal aortic aneurysms treated with PMEGs at Geral Roberto Santos (Salvador, Brazil) between January and February 2026.

The two patients included in this case series were treated under the approved protocol. Written informed consent for the publication of clinical data and imaging was obtained from the patients or their legal representatives.

Both patients were considered unsuitable for open repair because of the emergent nature of their presentation and the absence of immediately available custom-made devices. Therefore, an endovascular strategy using PMEGs was adopted.

Whenever intentional renal artery sacrifice was anticipated during procedural planning, the risks of postoperative renal dysfunction, including temporary or permanent dialysis dependence, were discussed preoperatively with the patient and/or their legal representatives. Specific informed consent for renal artery sacrifice was obtained before the intervention.

The procedures were performed using a thoracic endograft as the proximal component, followed by distal extension with abdominal endografts and iliac limbs.

The devices used included:

• Hercules® Thoracic Stent Graft as the proximal thoracic component (Microport®, Shanghai, China);

• Minos® Abdominal Stent Graft for distal aortic extension (Microport®, Shanghai, China); and

• Iliac limb extensions for distal sealing.

PMEG Modification Technique

The thoracic endograft was modified on the back table immediately before implantation. The locations of the fenestrations and branches were carefully marked according to measurements obtained from preoperative computed tomography angiography (CTA), taking into consideration the longitudinal distances between the visceral vessels and their circumferential orientation relative to the proximal landing zone.

Fenestrations were created using an electrocautery device (Cautermax®, Fabinject®, Taubaté, Brazil) to create openings in the graft fabric at the predetermined positions.

Each fenestration was subsequently reinforced with a snare catheter loop (Scitech Medical®, Aparecida de Goiânia, Brazil) to improve structural stability and fluoroscopic visibility.

The directional branches were constructed using self-expanding covered stents (Solaris®, Scitech Medical®, Aparecida de Goiânia, Brazil), which were integrated into the PMEG.

Case 1

A 26-year-old man presented to the emergency department with acute abdominal and lumbar pain associated with hemodynamic instability requiring a norepinephrine infusion.

Laboratory tests revealed severe renal dysfunction, with a urea level of 128 mg/dL, serum creatinine of 4.8 mg/dL, and an estimated glomerular filtration rate (eGFR) of 13.8 mL/min/1.73 m², calculated using the 2021 chronic kidney disease epidemiology collaboration (CKD-EPI) equation. The patient had no known history of renal dysfunction. Given the patient’s hemodynamic instability and aneurysm rupture, the elevated serum creatinine level was considered more consistent with acute kidney injury secondary to hemorrhagic shock, although previous laboratory data were unavailable to definitively exclude underlying chronic kidney disease.

Preoperative CTA demonstrated a ruptured Crawford type IV thoracoabdominal aortic aneurysm with a large retroperitoneal hematoma involving the origins of the celiac trunk, superior mesenteric artery, and renal arteries.

Given the patient’s young age and the complex aneurysm anatomy, an endovascular strategy using a PMEG was chosen to maintain perfusion of the main visceral vessels while avoiding the morbidity associated with open thoracoabdominal repair.

Preoperative planning was based on measurements obtained from CTA (Figure 1). Based on this analysis, a Hercules® thoracic endograft (MicroPort®, Shanghai, China) was modified. Two fenestrations were created, one for the celiac trunk and the other for the superior mesenteric artery, along with a directional branch for the right renal artery. The back-table modification process is illustrated in Figure 2.

Figure 1.

Preoperative CTA. (A) 3D reconstruction demonstrating a ruptured thoracoabdominal aortic aneurysm involving the visceral segment. (B) Sagittal CTA image demonstrating involvement of the visceral aorta and its relationship with the renal arteries.

CTA: Computed tomography angiography; 3D: Three dimensional.

Figure 2.

Bench modification of the PMEG demonstrating creation of two fenestrations for the celiac trunk and superior mesenteric artery and one directional branch for the right renal artery.

PMEG: Physician-modified endograft.

The left renal artery measured approximately 3 mm in diameter and had marked proximal angulation, making target-vessel catheterization and bridging stent implantation technically challenging. In the setting of rupture and hemodynamic instability, preservation of this vessel would have significantly prolonged the procedure; therefore, intentional sacrifice of the left renal artery was planned.

Following deployment of the modified thoracic endograft, the target vessels were catheterized and revascularized using balloon-expandable covered bridging stents (BeGraft®, Bentley®, Hechingen, Germany). Intraoperative angiographic findings are shown in Figure 3.

Figure 3.

Intraoperative angiography. (A) Large thoracoabdominal aneurysm during PMEG deployment. (B) Deployed endograft with bridging stents to the visceral vessels.

PMEG: Physician-modified endograft.

Distal sealing of the repair was achieved using a Minos® abdominal endograft and iliac extensions (Microport®, Shanghai, China).

Completion angiography demonstrated satisfactory exclusion of the aneurysm and patency of the visceral branches (Figure 3). The interval between the first and last fluoroscopic images was 3 hours and 54 minutes (11:08-15:02).

The postoperative course was complicated by abdominal compartment syndrome, which was managed conservatively with measures to reduce intra-abdominal pressure, as well as acute kidney injury requiring three sessions of hemodialysis and prolonged mechanical ventilation, resulting in a 20-day intensive care unit stay. Renal function progressively stabilized, allowing discontinuation of renal replacement therapy.

The patient was discharged after 28 days following an additional period of ward-based rehabilitation. Serum creatinine decreased to 2.9 mg/dL, urea to 119 mg/dL, and the eGFR improved to 25.2 mL/min/1.73 m².

Follow-up CTA performed 3 months after the procedure demonstrated good positioning of the endograft and patent visceral branches. A small type II endoleak originating from a lumbar artery was identified without aneurysm sac enlargement; therefore, conservative management with imaging surveillance was chosen. Postoperative imaging findings are shown in Figure 4. The patient remains under outpatient follow-up for further diagnostic evaluation.

Figure 4.

Three-month postoperative CTA. (A) 3D reconstruction demonstrating aneurysm exclusion and preserved visceral branch patency. (B) Axial CTA image demonstrating thrombosis of the aneurysm sac and a small type II endoleak originating from a lumbar artery, without aneurysm sac enlargement.

CTA: Computed tomography angiography; 3D: Three dimensional.

Case 2

The second case involved a 68-year-old woman with hypertension who was admitted with acute abdominal and back pain and hemorrhagic shock (systolic blood pressure, 75 mmHg).

Preoperative laboratory evaluation showed preserved renal function, with a urea level of 48 mg/dL, serum creatinine of 0.6 mg/dL, and an eGFR of 97.7 mL/min/1.73 m², calculated using the 2021 CKD-EPI equation.

CTA demonstrated a ruptured Crawford type IV thoracoabdominal aortic aneurysm measuring approximately 10 cm, involving the visceral aortic segment and associated with a large retroperitoneal hematoma. CTA also revealed small-caliber bilateral renal arteries, measuring approximately 2.5 mm in diameter, which substantially increased the technical complexity and risk associated with renal revascularization in the emergency setting. Preoperative CTA findings are shown in Figure 5.

Figure 5.

Preoperative CTA. (A): 3D reconstruction demonstrating a ruptured thoracoabdominal aneurysm involving the visceral segment. (B): Axial CTA image demonstrating the morphology of the aneurysm and reduced caliber of the right renal artery (RRA; yellow arrow) and left renal artery (LRA; green arrow).

CTA: Computed tomography angiography; 3D: Three dimensional; RRA: Right renal artery; LRA: Left renal artery.

The patient presented in hemorrhagic shock and was considered to be at prohibitive risk for open thoracoabdominal repair. Therefore, an endovascular approach using a PMEG was selected. Given the patient’s profound hemodynamic instability and unfavorable renal anatomy, the procedural strategy prioritized rapid aneurysm exclusion while maintaining perfusion to the superior mesenteric artery and celiac trunk. Because preservation of both renal arteries would have substantially increased procedural complexity and operative time, intentional bilateral renal artery sacrifice was planned. This strategy, including the anticipated risk of permanent dialysis-dependent renal failure, was discussed preoperatively with the patient and her family, and written informed consent was obtained before the procedure.

The PMEG was configured with two directional branches, one for the celiac trunk and the other for the superior mesenteric artery. This modification is illustrated in Figure 6.

Figure 6.

Bench modification of the PMEG with two directional branches for the celiac trunk and superior mesenteric artery.

PMEG: Physician-modified endograft.

Following deployment of the modified thoracic endograft, both vessels were catheterized and bridged using balloon-expandable covered stents (BeGraft®, Bentley®, Hechingen, Germany). Intraoperative angiographic images are shown in Figure 7.

Figure 7.

Intraoperative angiography. (A) Initial angiographic evaluation during emergent endovascular repair. (B) Selective catheterization and bridging stent placement to the visceral vessels.

For distal sealing, a Minos® abdominal endograft and iliac extensions (Microport®, Shanghai, China) were used. The interval between the first and last fluoroscopic images was 4 hours and 27 minutes (11:04-15:31).

The patient initially remained clinically stable, with successful weaning from vasoactive support, stable hemoglobin levels, and adequate visceral perfusion. As anticipated preoperatively, she developed severe acute kidney injury requiring renal replacement therapy and remained dialysis-dependent throughout her hospitalization. Laboratory tests obtained on postoperative day 3 demonstrated marked deterioration in renal function, with a serum creatinine level of 4.8 mg/dL, urea of 145 mg/dL, and an eGFR of 9.3 mL/min/1.73 m², calculated using the 2021 CKD-EPI equation.

Follow-up CTA performed 15 days after the procedure demonstrated near-complete thrombosis of the aneurysm sac. A small endoleak originating from the celiac fenestration was identified, without evidence of sac pressurization or aneurysm enlargement; therefore, conservative management with imaging surveillance was adopted. Follow-up CTA findings are shown in Figure 8.

Figure 8.

Follow-up CTA. (A) 3D reconstruction demonstrating successful aneurysm exclusion and visceral branch patency. (B) Sagittal and axial CTA image demonstrating thrombosis of the aneurysm sac and a small endoleak arising from the celiac branch.

CTA: Computed tomography angiography; 3D: Three dimensional.

During her subsequent intensive care unit stay, an attempt at ventilator weaning and extubation was unsuccessful, followed by cardiorespiratory arrest requiring resuscitation. Although spontaneous circulation was restored, the patient failed to regain consciousness after sedation was discontinued. Brain computed tomography demonstrated a hemorrhagic stroke. Despite ongoing intensive care support, her neurological condition progressively deteriorated, and she died 70 days after the procedure. No evidence of aneurysm-related complications or technical failure of the endovascular repair was identified during her postoperative course.

Discussion

Ruptured thoracoabdominal aortic aneurysms represent one of the most critical conditions in vascular surgery, with mortality rates that remain extremely high despite advances in surgical and endovascular techniques.^[12] In this context, rapid hemorrhage control and restoration of visceral perfusion are the primary priorities during emergent repair.

Endovascular approaches have significantly expanded treatment options for complex aortic pathology, particularly with the development of fenestrated and branched endografts, which allow preservation of visceral perfusion while avoiding the morbidity associated with open thoracoabdominal repair.^{[1, 2, 3, 4, 5, 6]} However, the applicability of custom-made devices in emergency situations remains limited by the time required for device manufacturing.^[7]

For this reason, PMEGs have emerged as a valuable alternative in urgent and emergent settings. By allowing rapid customization of commercially available thoracic stent grafts to incorporate fenestrations or directional branches, this technique makes it possible to extend endovascular treatment to patients who would otherwise have no viable option for complex aortic repair.^{[7, 8]}

Despite these advances, important technical challenges remain, particularly regarding the management of the renal arteries during emergent thoracoabdominal aneurysm repair.

The findings reported by Tanious et al.^[11] provide relevant evidence regarding renal artery coverage during emergent endovascular repair. In their analysis of patients undergoing EVAR for ruptured abdominal aortic aneurysms, bilateral renal artery coverage was associated with markedly poorer survival and higher rates of permanent dialysis, whereas unilateral renal artery coverage did not significantly affect in-hospital mortality or 1-year survival. These observations support the concept that procedural simplification and rapid hemorrhage control may occasionally outweigh the benefits of complete renal preservation in critically unstable patients.

In elective thoracoabdominal aortic repair, preservation of both renal arteries is widely recognized as an important objective. Renal perfusion plays a key role in postoperative outcomes, and renal artery occlusion has been consistently associated with reduced survival and increased long-term morbidity after complex aortic repair.^{[9, 10]} The development of postoperative renal failure, particularly when dialysis is required, is strongly associated with poorer long-term survival and an increased risk of cardiovascular complications.^[9]

Therefore, whenever technically feasible, preservation of renal perfusion should remain a fundamental goal during thoracoabdominal aneurysm repair.

However, clinical priorities may change significantly in the setting of ruptured aneurysms, where patient survival depends primarily on rapid aneurysm exclusion and stabilization of the hemodynamic status. In these situations, procedural complexity becomes a critical determinant of outcome.

Attempting to preserve the renal arteries in unfavorable anatomical scenarios—such as small vessel diameter, severe angulation, or difficult catheterization—may significantly prolong operative time and increase procedural risk. Prolonged procedures in unstable patients can exacerbate metabolic acidosis, increase blood loss, and contribute to multiorgan dysfunction.

Very small renal arteries, such as those observed in the second case of the present report, represent a particular technical challenge for branch catheterization and bridging stent deployment. Even when technically successful, the long-term patency of such small vessels may remain uncertain.

For these reasons, a selective and individualized strategy may be required when managing the renal arteries during emergent thoracoabdominal repair. When anatomical conditions are favorable and the patient’s hemodynamic status allows, renal preservation should be pursued. This approach may be particularly important in younger patients, in whom long-term renal function plays a major role in survival and quality of life.

Conversely, when renal anatomy is unfavorable or procedural complexity may compromise patient stability, simplification of the repair aimed at rapid aneurysm exclusion and preservation of mesenteric circulation may represent the safest strategy.

The cases presented in this report illustrate two different approaches within this clinical spectrum. In the first case, unilateral renal preservation was achieved through a directional branch to the right renal artery, whereas the contralateral renal artery was intentionally sacrificed. In the second case, the extremely small caliber of both renal arteries, combined with aneurysm rupture, led to a strategy focused on rapid visceral revascularization without renal preservation.

In the first patient, unilateral renal preservation was associated with transient dialysis-dependent acute kidney injury, followed by partial renal recovery. In contrast, in the second patient, bilateral renal artery sacrifice resulted in permanent dialysis-dependent renal failure despite successful aneurysm exclusion and preservation of visceral perfusion. The patient subsequently died 70 days after the procedure following cardiorespiratory arrest and hemorrhagic stroke.

These findings emphasize that the optimal strategy for renal artery management during emergent PMEG repair requires careful consideration of anatomical feasibility, procedural complexity, and the patient’s hemodynamic status. They also underscore that survival after ruptured thoracoabdominal aneurysm repair depends not only on technical success but also on the severity of systemic complications associated with hemorrhagic shock and critical illness.

An important limitation in interpreting the present findings is that the available evidence supporting selective renal artery coverage during emergency endovascular repair is largely derived from patients undergoing EVAR for ruptured infrarenal abdominal aortic aneurysms. Although these studies provide valuable insight into the balance between procedural simplification and renal preservation, direct extrapolation to ruptured thoracoabdominal aortic aneurysms should be made with caution because of their greater anatomical complexity, the need for visceral and branch-vessel reconstruction, and the potentially longer procedural times associated with PMEG repair.

Emergency repair of ruptured thoracoabdominal aneurysms using PMEGs is a viable strategy when custom-made devices are unavailable. Although renal artery preservation remains an important determinant of long-term outcomes and should be pursued whenever technically feasible, priorities in the setting of rupture differ substantially from those in elective repair.

These cases suggest that selective renal artery sacrifice may occasionally represent a reasonable option in carefully selected emergency situations when anatomical complexity or profound hemodynamic instability precludes safe renal revascularization. However, the present report is descriptive and does not permit conclusions regarding the impact of this strategy on survival.