Clinical outcomes of hybrid surgery in the treatment of aortic arch disease: a retrospective study

Introduction

Due to their anatomical complexity, aortic arch pathologies present a formidable challenge in cardiovascular surgery (1) and are associated with a high risk of life-threatening complications. In recent decades, a range of surgical techniques have been refined to achieve durable aortic reconstruction while minimizing perioperative morbidity and mortality (2). Nevertheless, the intricate relationships of the aortic arch with the supra-aortic branches, heart, and descending thoracic aorta continue to complicate treatment decisions and limit therapeutic options (3). Conventional open surgical repair has long served as the primary approach to aortic arch disease, with early pioneers such as Michael E. DeBakey, Denton A. Cooley, and E. Stanley Crawford laying the foundation for modern aortic surgery (4). Although effective in high-volume centers, these procedures are associated with substantial physiological burden, including prolonged operative times, significant blood loss, neurologic injury, and multi-organ dysfunction, prompting sustained efforts to develop less invasive strategies that preserve or improve patient prognosis (5).

The advent of endovascular technology has enabled the evolution of hybrid aortic repair (HAR), which combines limited open surgical supra-aortic debranching with thoracic endovascular aortic repair (TEVAR). This integrated approach has emerged as a valuable alternative, particularly for high-risk or elderly patients with extensive arch involvement or unfavorable anatomy for total open reconstruction (6). Early- and mid-term results from multiple institutional series and meta-analyses of HAR have reported acceptable perioperative mortality rates (typically 6–12%) and stroke rates (4–8%), often comparable to or better than those of conventional open repair in selected cohorts, and have shown that HAR substantially reduces the need for deep hypothermic circulatory arrest (DHCA) and its potential complications (7).

Despite these advantages, hybrid techniques are not free of limitations. Contemporary literature highlights several persistent concerns, including a higher incidence of type I endoleaks, stent-graft migration, stent-induced new entry tears, retrograde type A dissection (RTAD), and the requirement for late reintervention (reported in 10–27% of cases at mid-term follow-up) (8,9). Long-term durability also remains a subject of ongoing debate, with some comparative studies indicating inferior freedom from aortic events and reoperation relative to open repair, particularly beyond 3–5 years (10). Institutional experience, patient selection, and landing-zone anatomy have a substantial influence on outcomes (11). HAR is generally reserved for patients with significant comorbidities or prohibitive risk for conventional surgery, and its role in younger or low-risk individuals continues to be debated (12). These uncertainties underscore the need for rigorous comparative analyses to better define the safety, efficacy, and durability profile of HAR in real-world practice.

Thus, the clinical effectiveness and safety of HAR urgently need to be assessed to inform evidence-based decision-making, refine patient selection criteria, and optimize long-term outcomes in this complex condition. The present study was designed to compare the outcomes of patients with distal aortic arch disease treated at our institution with HAR, consisting of supra-aortic debranching combined with TEVAR, or the frozen elephant trunk (FET) procedure. Inverse probability of treatment weighting (IPTW) was applied to minimize confounding bias and generate balanced comparative data to guide future therapeutic strategies. We present this article in accordance with the STROBE reporting checklist (available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1540/rc).

Methods

Study design and patient population

A single-center, retrospective, observational cohort study was conducted. This study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Ethics Committee of Beijing Anzhen Hospital (Institutional Review Board File No. 2014019). Because the study used previously collected, de-identified data and involved no direct patient contact or intervention, the requirement for written informed consent was waived in accordance with institutional policy for retrospective observational research.

From January 2015 to February 2023, 785 patients with aortic arch disease involving the aortic arch but not the ascending aorta, treated at Beijing Anzhen Hospital, were enrolled in the study (including patients with aortic dissection, ulcer, and hematoma). The sample size was determined by the total number of consecutive patients who met the eligibility criteria during the specified timeframe. Among these patients, 406 underwent one-stage hybrid arch repair consisting of supra-aortic debranching followed by TEVAR (the HAR group), and 379 underwent the FET procedure combined with supra-aortic branch reconstruction (the FET group). The inclusion criteria for the study were as follows: (I) a diagnosis of aortic arch disease based on preoperative computed tomography angiography (CTA), with no involvement of the ascending aorta; and (II) no history of prior cardiac surgery. The exclusion criteria were as follows: (I) severe preoperative hepatic dysfunction or coagulation disorders; (II) preoperative use of antiplatelet or anticoagulant agents, such as aspirin or clopidogrel; (III) severe preoperative limb ischemia, severe gastrointestinal malperfusion, coma, or paraplegia; (IV) infectious aortic disease; and/or (V) pregnancy.

Treatment strategy was determined by a multidisciplinary aortic team consisting of senior cardiovascular surgeons, interventional cardiologists, and radiologists, based on patient age, comorbidities, anatomical characteristics, landing-zone suitability, and operative risk. In this study, “older patients” generally referred to patients aged ≥60 years or those with advanced physiological age due to multiple comorbidities, reduced cardiopulmonary reserve, or frailty. Open FET repair was generally preferred for younger patients and those with complex arch lesions who were able to tolerate cardiopulmonary bypass (CPB) and circulatory arrest, whereas HAR was primarily considered for older or high-risk patients who were not considered suitable candidates for conventional open arch reconstruction. All procedures were performed by senior aortic surgeons at our center who had extensive experience in both HAR and FET procedures. The final operative strategy and surgeon assignment were made according to multidisciplinary assessment, lesion anatomy, operative risk, and the expertise of the attending surgical team.

Data collection

Collected variables were categorized as follows: (I) preoperative variables [age, sex, body mass index (BMI), systolic blood pressure, diastolic blood pressure, hypertension, diabetes, hyperlipidemia, history of coronary heart disease, history of cerebrovascular disease, history of renal insufficiency, chronic obstructive pulmonary disease (COPD), smoking status, alcohol use, left ventricular end-systolic diameter (LVESD), left ventricular ejection fraction (LVEF), ascending aortic inner diameter (AAID), and aortic sinus inner diameter (ASID)]; (II) intraoperative variables [operative time, blood loss volume, CPB time, aortic cross-clamping time, circulatory arrest time, lowest nasopharyngeal temperature during extracorporeal circulation, lowest rectal temperature during extracorporeal circulation, concomitant coronary artery bypass grafting (CABG), and concomitant aortic valve plasty (AVP)]; and (III) postoperative outcomes [postoperative recovery time, intensive care unit (ICU) stay, stroke, paraplegia, postoperative dialysis, in-hospital mortality, pulmonary infection, reintubation, tracheotomy, limb paralysis, limb ischemia, cardiac tamponade, arrhythmia, reoperation for bleeding, pleural effusion, pneumothorax, respiratory failure, incision complication, sternal dehiscence, and debridement]; and (IV) follow-up variables [survival status, all-cause death, reintervention, and follow-up duration].

Although patients with ascending aortic involvement were excluded, ascending aortic and aortic root diameters were measured as part of the routine preoperative anatomical assessment. These measurements were used to confirm the absence of significant proximal aortic dilation or root disease, to evaluate the suitability of the ascending aorta for supra-aortic debranching in the HAR group, and to describe baseline anatomical comparability between the two treatment groups.

End points and definitions

The primary end point of this study was postoperative mortality, while the secondary endpoints included reintervention, perioperative stroke, paraplegia, and dialysis. Aortic dissection was defined as an intimal tear with propagation of the blood into the media, resulting in the separation of the aortic wall layers by an intimal flap and the formation of true and false lumina, with or without re-entry communication. Secondary intervention was defined as any subsequent surgical or endovascular procedure required due to aorta-related complications following the initial operation, such as anastomotic pseudoaneurysm, endoleak, distal aortic dilation, or new-onset dissection. Postoperative recovery time was defined as the interval from the end of surgery to recovery of consciousness with stable vital signs, as recorded in the postoperative recovery or ICU records, and was measured in minutes. Perioperative stroke was defined as new-onset ischemic or hemorrhagic stroke occurring within 30 days postoperatively or during hospitalization, confirmed by computed tomography or magnetic resonance imaging, and accompanied by neurological deficits persisting for ≥24 hours. Paraplegia was defined as temporary or permanent lower-extremity motor dysfunction due to spinal cord ischemia, diagnosed by neurological examination after patient awakening. Postoperative dialysis was defined as renal replacement therapy, including continuous renal replacement therapy, hemodialysis, or peritoneal dialysis, initiated within 30 days after surgery for new-onset or worsened postoperative renal dysfunction. Patients with pre-existing dialysis dependence were excluded from this endpoint. This definition corresponded to Kidney Disease: Improving Global Outcomes stage 3 acute kidney injury requiring renal replacement therapy. Follow-up mortality was defined as all-cause mortality during the follow-up period. Because the specific cause of death could not be reliably adjudicated in all patients due to the retrospective nature of the study and the use of telephone follow-up, aortic-related mortality was not analyzed as a separate endpoint.

Surgery details

Hybrid surgery

Different strategies for supra-aortic debranching were selected according to the involved aortic arch segments, the intended proximal landing zone, and the anatomical relationship between the lesion and the supra-aortic branches. In the present cohort, HAR procedures were mainly classified as type I or type IV according to the extent of debranching and the location of the proximal landing zone. Other hybrid configurations were not routinely used because the included patients had distal aortic arch disease without ascending aortic involvement, and the operative strategy was designed to create an adequate proximal landing zone for TEVAR while avoiding unnecessary arch reconstruction.

All HAR procedures were performed under general anesthesia. Preoperative CTA was used to evaluate the location of the primary lesion, supra-aortic branch involvement, proximal and distal landing zones, aortic arch diameter, access vessels, and the presence of aortic calcification or mural thrombus. After systemic heparinization, supra-aortic debranching was performed first, followed by endovascular stent-graft implantation. CPB was not routinely used in HAR.

Type I HAR was performed in patients with a morphologically suitable native ascending aorta, generally with an ascending aortic diameter <4 cm and without severe calcification. After systemic heparinization, the ascending aorta was partially clamped using a side-biting clamp. The proximal end of a trimmed bifurcated or trifurcated Dacron graft was anastomosed end-to-side to the ascending aorta using continuous 5-0 Prolene sutures. The innominate artery and left common carotid artery were then transected at their origins and reconstructed by end-to-end anastomosis to the corresponding graft branches. The left subclavian artery was managed through a cervical incision by constructing a left common carotid artery-left subclavian artery bypass, followed by proximal ligation of the left subclavian artery when necessary. This procedure was mainly used for patients with zone 1 lesions, defined as primary intimal tears of aortic dissection, penetrating atherosclerotic ulcers, or intramural hematomas located between the distal edge of the innominate artery and the origin of the left common carotid artery.

Type IV HAR was mainly used for older or high-risk patients with severe comorbidities who were considered unable to tolerate open arch reconstruction or ascending aortic clamping. In these patients, partial supra-aortic debranching was performed through limited cervical incisions, most commonly by constructing a left common carotid artery-left subclavian artery bypass, with proximal occlusion or ligation of the left subclavian artery when necessary. TEVAR was then performed with the proximal stent-graft landing zone located in zone 1 or zone 2 according to the extent of disease and the adequacy of the landing zone. This procedure was mainly indicated for patients with lesions located in zone 2 or 3, in whom partial debranching was sufficient to preserve supra-aortic branch perfusion and obtain an adequate proximal landing zone.

After completion of debranching, TEVAR was performed via the femoral artery under fluoroscopic guidance. The TEVAR stent-grafts used in this study included commercially available devices from W. L. Gore & Associates, Flagstaff, AZ, USA; Cook Medical, Bloomington, IN, USA; and Medtronic, Minneapolis, MN, USA, with a main body diameter of 18–42 mm and a length of 100–200 mm. Completion angiography was routinely performed to confirm patency of the reconstructed supra-aortic branches and bypass grafts, adequate stent-graft positioning, exclusion of the primary lesion, integrity of the anastomoses, and absence of major endoleak. The proximal and distal sealing zones and the need for adjunctive procedures were determined according to preoperative CTA and intraoperative angiographic findings (13,14). Postoperative CTA surveillance was used to further assess branch and bypass patency, stent-graft position, endoleak, distal aortic dilation, false lumen status, and other aorta-related complications. For patients who underwent concomitant AVP, valve function was assessed by intraoperative transesophageal echocardiography and postoperative transthoracic echocardiography.

The FET procedure

All FET procedures were performed under general anesthesia through a standard median sternotomy. After exposure of the ascending aorta, aortic arch, and supra-aortic branches, the right axillary artery was dissected for arterial cannulation. CPB was established through right axillary artery cannulation for arterial inflow and right atrial cannulation for venous drainage, followed by systemic cooling. After aortic cross-clamping, the ascending aorta was opened, and myocardial protection was achieved by antegrade infusion of cold blood cardioplegia or histidine-tryptophan-ketoglutarate solution through the coronary ostia. When concomitant aortic valve, Valsalva sinus, or ascending aortic procedures were required, they were performed after aortic cross-clamping and cardioplegic arrest and before distal arch reconstruction. Patients with primary ascending aortic involvement requiring extensive ascending aortic or root replacement were not included in this study.

When the nasopharyngeal temperature reached approximately 25 ℃, lower-body circulatory arrest was initiated. The origins of the supra-aortic branches were sequentially clamped, and selective antegrade cerebral perfusion was delivered through the right axillary artery at 5–10 mL/kg/min, with a mean cerebral perfusion pressure of 40–60 mmHg. The aortic arch was opened and transected between the left common carotid artery and the left subclavian artery. After confirming that the guidewire and delivery system were located in the true lumen of the descending aorta, an appropriately sized FET stent-graft was deployed antegradely into the descending thoracic aorta.

The FET devices used in this study included commercially available stent-grafts from Terumo Aortic, Glasgow, UK, or MicroPort Medical Co., Shanghai, China. Device size was selected according to the diameter and extent of the diseased descending aorta, with typical graft diameters of 26–30 mm, stent outer diameters of 20–40 mm, and lengths of 120–180 mm. The distal end of the stent-graft was controlled to remain above the T8 vertebral level whenever possible.

After FET deployment, the distal anastomosis was performed using a continuous “parachute” technique combined with a three-layer sandwich anastomosis, incorporating the proximal fabric collar of the FET stent-graft, the native descending aortic wall, and the distal end of a four-branched Dacron graft with continuous 3-0 or 4-0 Prolene sutures. Lower-body perfusion was then resumed through the perfusion side branch of the four-branched graft, and systemic rewarming was initiated. The left common carotid artery was reconstructed first, followed by the proximal anastomosis to the ascending aorta and release of the aortic cross-clamp. Finally, the innominate artery and left subclavian artery were sequentially anastomosed to the remaining branches of the graft under beating-heart conditions with CPB support. After inspection of all anastomoses and hemostasis, CPB was discontinued, mediastinal drains were placed, and the chest was closed in layers.

Follow-up monitoring

Preoperative and perioperative data were retrospectively collected from the hospital’s cardiac and vascular research database. Additional information regarding clinical outcomes, reintervention, and long-term survival was obtained through chart reviews or telephone interviews. All patients were advised to undergo postoperative CTA surveillance before discharge, at 3, 6, and 12 months after surgery, and annually thereafter. CTA was used in routine clinical practice to assess stent-graft position, patency of the reconstructed supra-aortic branches, endoleak, distal aortic dilation, false lumen status, and other aorta-related complications. However, because of the retrospective design and incomplete availability of standardized follow-up CTA images across the entire cohort, quantitative CTA-based aortic remodeling parameters were not systematically collected or analyzed in the present study.

Statistical analysis

Continuous variables are reported as mean ± standard deviation. Categorical variables are presented as frequencies and percentages. The Student’s t-test was used to compare normally distributed continuous variables, while the Mann-Whitney U test was applied for non-normally distributed continuous variables. The Chi-squared test and Fisher’s exact test were used for categorical variable comparisons. All P values were two-sided, and a P value <0.05 was considered statistically significant. All analyses were conducted on an intention-to-treat basis. The postoperative survival curves of all discharged patients were constructed using the Kaplan-Meier method, and differences between groups were assessed using the log-rank test. Patients lost to follow-up were treated as right-censored observations at the date of their last known clinical contact in the survival analysis. Hazard ratios and 95% confidence intervals for survival outcomes were calculated using Cox proportional hazards regression models. Multiple imputation was used to impute missing values in the baseline data. IPTW was used to balance the baseline covariates between the treatment groups and minimize selection bias in the observational cohort analysis. The following covariates were included in the propensity model: age, sex, BMI, time of onset, smoking status, diabetes, hypertension, history of cerebral infarction, history of cardiovascular disease, and LVEF. All analyses were conducted using R software (version 4.4.2).

Results

Baseline characteristics of the study population

A total of 785 patients with aortic arch disease were enrolled in the study, including 406 in the HAR group and 379 in the FET group. Before IPTW, significant differences were observed between the two groups. Specifically, the patients in the HAR group were significantly older than those in the FET group [57.0 (49.0, 66.0) vs. 49.0 (40.0, 56.0) years, P<0.001]. Higher proportions of diabetes (9.6% vs. 5.5%, P=0.045), hyperlipidemia (21.7% vs. 9.0%, P<0.001), and a history of coronary heart disease (14.0% vs. 7.4%, P=0.004) were also observed in the HAR group. No significant differences were observed between the two groups in terms of sex, hypertension, cerebrovascular disease, renal insufficiency, COPD, smoking status, or alcohol use before adjustment (Table 1).

After IPTW adjustment, the baseline characteristics were well balanced between the HAR (n=796.7) and FET (n=771.3) groups, with no statistically significant differences observed between the two groups in relation to any of the variables, including age (P=0.82), diabetes (P=0.54), hyperlipidemia (P=0.76), and coronary heart disease (P=0.20) (Table 1). The standardized mean difference plot further confirmed adequate balance after IPTW (Figure 1).

Figure 1 The SMD of the IPTW. BMI, body mass index; IPTW, inverse probability of treatment weighting; LVEF, left ventricular ejection fraction; SMD, standardized mean difference.

Preoperative imaging and hemodynamic findings

The preoperative echocardiographic parameters were comparable between the two groups. No significant differences were observed between the two groups in terms of left ventricular end-systolic internal diameter, LVEF, or aortic sinus internal diameter before or after IPTW adjustment. However, the ascending aortic internal diameter was slightly larger in the HAR group before adjustment [37.0 (34.0, 40.0) vs. 36.0 (33.0, 38.0) mm, P=0.02], but this difference was no longer significant after IPTW (P=0.98). Blood pressure parameters (systolic and diastolic) and BMI were similar between groups both before and after adjustment (Table 1).

Operation details

Operative characteristics are summarized in Table 2. Before IPTW adjustment, the HAR group demonstrated a significantly shorter operation duration [5.5 (4.5, 6.5) vs. 6.5 (6.0, 7.0) hours, P=0.02], lower blood loss volume [400.0 (150.0, 800.0) vs. 800.0 (600.0, 1,000.0) mL, P<0.001], and shorter postoperative recovery time [165.0 (75.0, 268.7) vs. 225.0 (145.0, 300.0) min, P<0.001] compared with the FET group. After IPTW adjustment, the difference in blood loss volume remained statistically significant [500.0 (200.0, 900.0) vs. 800.0 (600.0, 1,000.0) mL, P=0.03], while the differences in operative time and recovery time were no longer significant (P=0.18 and P=0.39, respectively). Detailed intraoperative data for the FET group, including CPB time, aortic cross-clamping time, and circulatory arrest time, are presented in Table 2.

Perioperative outcomes

After IPTW adjustment, the HAR group continued to show a significantly lower incidence of pleural effusion (2.6% vs. 19.0%, P<0.001) and pulmonary infection (1.2% vs. 4.4%, P=0.02) compared with the FET group. No significant differences were observed between the two groups in terms of in-hospital mortality (0.5% vs. 1.5%, P=0.10), stroke (1.5% vs. 0.8%, P=0.26), paraplegia (2.4% vs. 1.8%, P=0.72), or dialysis (0.8% vs. 1.2%, P=0.61). Although the difference was not statistically significant, the incidence of stroke was numerically higher in the HAR group after adjustment (1.5% vs. 0.8%, P=0.26) (Table 3).

Follow-up outcomes

The median follow-up duration was 36 months, with a range of 1 to 96 months. During follow-up, 37 all-cause deaths (8.6%) were observed in the HAR group and 15 (3.9%) in the FET group. Kaplan-Meier survival analysis before IPTW adjustment showed a higher mortality rate in the HAR group (log-rank P=0.04), but after IPTW adjustment, the difference was no longer statistically significant (P=0.18) (Figure 2).

Figure 2 Long-term survival according to surgical strategy. (A) Kaplan-Meier curves for mortality in patients from the FET and HAR groups without IPTW adjustment; (B) Kaplan-Meier curves for mortality in patients from the FET and HAR groups with IPTW adjustment. FET, frozen elephant trunk; HAR, hybrid aortic repair; IPTW, inverse probability of treatment weighting.

Freedom from reintervention was comparable between the two groups both before (log-rank P=0.19) and after (log-rank P=0.11) IPTW adjustment (Figure 3). In the subgroup of patients younger than 60 years, no significant differences in mortality were observed between the HAR and FET groups before (P=0.38) or after (P=0.55) IPTW adjustment (Figure 4).

Figure 3 Freedom from aortic reintervention according to surgical strategy. (A) Kaplan-Meier curves for freedom from reintervention in patients from the FET and HAR groups without IPTW adjustment; (B) Kaplan-Meier curves for freedom from reintervention in patients from the FET and HAR groups with IPTW adjustment. FET, frozen elephant trunk; HAR, hybrid aortic repair; IPTW, inverse probability of treatment weighting.

Figure 4 Long-term survival according to surgical strategy in patients younger than 60 years. (A) Kaplan-Meier curves for mortality in patients under 60 years of age from the FET and HAR groups without IPTW adjustment; (B) Kaplan-Meier curves for mortality in patients under 60 years of age from the FET and HAR groups with IPTW adjustment. FET, frozen elephant trunk; HAR, hybrid aortic repair; IPTW, inverse probability of treatment weighting.

Discussion

This study confirmed that, while HAR demonstrates a clear advantage in reducing surgical trauma in high-risk patients, it does not show superior outcomes compared with the traditional FET procedure in terms of neurological complication rates or mid-term survival.

Before IPTW adjustment, the patients in the unadjusted HAR cohort were significantly older and had a higher prevalence of baseline comorbidities, including diabetes, hyperlipidemia, and coronary artery disease. This discrepancy in baseline characteristics reflects real-world clinical decision-making: HAR serves primarily as a crucial alternative strategy for frail patients whose advanced age or poor physiological condition precludes them from undergoing conventional open-chest surgery and CPB.

Consistent with multiple propensity-matched studies (10), the HAR group demonstrated a superior perioperative profile in this study. The significant reduction in blood loss and transfusion requirements in the HAR group can be mechanistically attributed to the avoidance or minimization of DHCA. By maintaining physiological temperatures or utilizing only mild hypothermia, HAR preserves enzymatic function and platelet activity, thereby mitigating the coagulopathy often associated with prolonged CPB (15). Further, the avoidance of extensive aortic cross-clamping and complex distal anastomoses reduces the risk of mechanical bleeding from needle holes, a common challenge in conventional arch replacement.

Notably, the HAR group exhibited a significantly lower incidence of respiratory complications, including pleural effusion and pulmonary infection. This benefit is likely attributable to the attenuation of systemic inflammatory response syndrome. Conventional FET procedures, often requiring prolonged CPB durations, may trigger neutrophil sequestration in the pulmonary vasculature, leading to “pump lung” or post-perfusion lung syndrome (16). By reducing CPB time and avoiding the extensive mediastinal dissection required to expose the distal arch in the FET procedure, HAR preserves chest wall stability and respiratory mechanics, thereby facilitating earlier extubation and shorter ICU stays. Consequently, HAR remains a compelling strategy for patients with severe pulmonary comorbidities or those deemed unfit for the physiological stress of open surgery.

Despite the theoretical advantage of avoiding DHCA to prevent global cerebral ischemia, our results—and the broader literature—suggest that HAR is not a superior strategy for neurological protection (17). In our study, the HAR group showed a non-significant trend toward a higher incidence of postoperative stroke compared with the FET group. This observation reveals a drawback of endovascular arch repair: embolic stroke. Unlike open repair (FET), where the aorta is opened and flushed under visual control, allowing for the removal of floating thrombus, HAR relies on the retrograde manipulation of guidewires and large-bore delivery systems through a potentially atherosclerotic aortic arch. This manipulation may mechanically dislodge atheromatous debris, causing embolic showers to the brain (18). Meta-analyses have indicated that while HAR reduces visceral ischemia, it may exchange global ischemic risks for focal embolic risks (19). Further, the deployment of stent-grafts in zone 0 or zone 1 involves rapid flow changes and balloon modeling, which may further destabilize aortic wall debris. Therefore, in patients with a heavy plaque burden in the arch, open surgery may offer superior neurological safety compared with the endovascular approach.

While HAR provides an excellent immediate solution, the question of long-term durability remains an important consideration. The fundamental difference lies in the nature of the repair: the FET procedure provides a definitive surgical replacement of the diseased arch, whereas HAR relies on the radial force of a stent-graft to seal the pathology. Our analysis of reintervention rates, although statistically comparable in the adjusted cohort, showed a numerical trend favoring the FET procedure, which aligns with long-term data from other centers and recent contemporary reviews highlighting the established long-term durability of open arch reconstruction (20-23). The primary mode of failure in HAR is the development of endoleaks, particularly type Ia endoleaks, due to the high hemodynamic shear stress in the aortic arch and the potential for progressive dilation of the native landing zone (24,25). Conversely, the FET procedure, by suturing the graft to the aortic wall, eliminates the risk of proximal type I endoleaks and promotes positive aortic remodeling.

The FET procedure has been shown to effectively expand the true lumen and promote thrombosis of the false lumen in over 90% of cases, providing a more stable long-term solution for aortic dissection (26). Further, HAR carries the specific risk of RTAD induced by the proximal bare springs of the stent-graft or wire injury, a catastrophic complication that is virtually non-existent after total arch replacement using the FET procedure (27).

A critical component of HAR is the durability of the supra-aortic debranching (e.g., carotid-carotid or carotid-subclavian bypass). Our study supports existing evidence that these bypasses have excellent long-term patency rates, often exceeding 95% at 5 years (28). However, vigilance is required, as occlusion of long-segment bypasses (e.g., axillary-axillary grafts) may lead to limb ischemia or, more critically, posterior circulation stroke if the vertebral artery flow is compromised.

Finally, the choice between HAR and the FET procedure often transcends pure clinical data and involves multifactorial considerations. The FET procedure is highly complex and technically demanding, characterized by a steep learning curve that requires mastery of intricate anastomoses and cerebral protection strategies. Conversely, HAR has a shorter learning curve and higher reproducibility, making it an accessible option for lower-volume centers or in emergent settings where expertise in total arch replacement may not be immediately available (29). A major practical advantage of the hybrid approach is its broader applicability. By lowering the technical threshold, it enables a wider range of hospitals to offer timely, life-saving interventions for acute aortic syndromes.

This study had a number of limitations. First, as a single-center, retrospective analysis, inherent selection bias exists in the allocation of patients to either the HAR or FET group. Although IPTW was used to mitigate baseline differences, unmeasured confounders may still have influenced the results. Second, the choice of surgical strategy was non-randomized and was largely determined by the surgeons’ assessment of individual anatomical complexity and comorbidities, which may introduce indication bias. Third, although postoperative CTA surveillance was routinely recommended and used for clinical follow-up, standardized CTA-based measurements of aortic remodeling were not systematically collected in all patients; therefore, a detailed comparison of aortic remodeling between HAR and FET could not be performed. Future prospective studies with standardized imaging protocols are needed to compare aortic remodeling after these two procedures and to better inform treatment selection. In addition, follow-up mortality was analyzed as all-cause mortality. Because of the retrospective design and the use of telephone follow-up for some patients, the specific cause of death could not be reliably adjudicated in all cases; therefore, aortic-related mortality was not analyzed separately. Finally, our cohort consisted exclusively of an Asian population; given potential ethnic differences in aortic anatomy and genetic background, these findings may not be fully generalizable to Western populations.

Conclusions

In this single-center retrospective study, HAR demonstrated comparable postoperative mortality and reintervention rates to the FET procedure, with the advantages of shorter operative time, reduced blood loss, and fewer specific pulmonary complications. These findings support HAR as a feasible alternative for selected high-risk patients with distal aortic arch disease. However, HAR may be associated with an increased risk of neurological complications and potential graft-related concerns. Therefore, strict patient selection, careful anatomical assessment, long-term imaging surveillance, and continued technical optimization are necessary to improve the safety and durability of hybrid and endovascular approaches in aortic arch surgery.

Acknowledgments

The authors would like to thank AiMi (https://www.aimieditor.com/) for providing linguistic assistance.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1540/rc

Data Sharing Statement: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1540/dss

Peer Review File: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1540/prf

Funding: This work was supported by the National Science and Technology Major Project (No. 2024ZD0538400), the Beijing Municipal Science & Technology Commission (No. Z221100007422015), the Beijing Hospitals Authority Clinical Medicine Development of special funding support (No. ZLRL202317), the National Natural Science Foundation of China (No. 82070483), the Beijing Natural Science Foundation (No. L232030), the Beijing Advanced Innovation Center for Big Data-based Precision Medicine (No. PXM2021_014226_000026), and the Scientific Research Common Program of Beijing Municipal Commission of Education (No. KM202110025014).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1540/coif). All authors report funding support from the National Science and Technology Major Project (No. 2024ZD0538400), the Beijing Municipal Science & Technology Commission (No. Z221100007422015), the Beijing Hospitals Authority Clinical Medicine Development of special funding support (No. ZLRL202317), the National Natural Science Foundation of China (No. 82070483), the Beijing Natural Science Foundation (No. L232030), the Beijing Advanced Innovation Center for Big Data-based Precision Medicine (No. PXM2021_014226_000026), and the Scientific Research Common Program of Beijing Municipal Commission of Education (No. KM202110025014). The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Ethics Committee of Beijing Anzhen Hospital (Institutional Review Board File No. 2014019). Because the study used previously collected, de-identified data and involved no direct patient contact or intervention, the requirement for written informed consent was waived in accordance with institutional policy for retrospective observational research.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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(English Language Editor: L. Huleatt)