Abstract
Objectives
Acute type A aortic dissection (ATAAD) patients with isolated left vertebral artery (ILVA) are at greater risk of brain damage during perioperative period. This study aims to evaluate the prognosis of ATAAD patients with ILVA.
Methods
This retrospective cohort study enrolled ATAAD patients and assigned them to the ILVA group or control group based on the presence of ILVA. A 1:2 propensity score matching (PSM) was employed using gender, age and surgical method. The primary outcome was defined as the incidence of major adverse cardiovascular and cerebrovascular events (MACCE) at 18-month follow-up, which included all-cause death, myocardial infarction and stroke.
Results
Following PSM, 117 patients were enrolled, including 39 patients in the ILVA group. The ILVA group had higher incidences of MACCE [19 (48.7%) vs. 11 (14.1%), P < 0.001], all-cause death [17 (43.6%) vs. 9 (11.5%), P < 0.001] and stroke [5 (12.8%) vs. 2 (2.6%), P = 0.018] compared to the control group. Multivariate cox regression indicated that ILVA [HR = 2.60, 95%CI: 1.17–5.80, P = 0.019], renal insufficiency [HR = 1.93, 95%CI: 1.10–3.39, P = 0.023] and cardiopulmonary bypass (CPB) time [HR = 1.01, 95%CI: 1.00-1.01, P = 0.026] were independent risk factors for MACCE at 18-month. There was no significant difference in the modified Rankin scale scores at 18-month. ILVA was not significantly associated with in-hospital mortality.
Conclusions
The incidence of MACCE at 18-month follow-up was higher in ATAAD patients with ILVA. ILVA, renal insufficiency and CPB time were identified as risk factors for MACCE for ATAAD patients. ILVA might serve as a risk factor for cardiovascular risk, but not for early postoperative mortality. Special attention should be attached to ATAAD patients with ILVA to improve the long-term prognosis.
Keywords: Isolated left vertebral artery, Aortic dissection, MACCE, Prognosis
Introduction
Acute Stanford type A aortic dissection (ATAAD) is a critical cardiovascular condition that necessitates emergency surgical intervention. Many patients with ATAAD present with tears extending from the inner lining of the ascending aorta to the arch of the aorta. Hemiarch and total arch replacement can effectively repair the aorta [1]. Isolated left vertebral artery (ILVA), which arises directly from the aortic arch on its left side, represents the second most common anatomic variant of the supra-aortic configuration, accounting for 5% of all aortic arch abnormal branching patterns [2–4]. ILVA bears the most blood flow to the brain, and its injury can readily lead to cerebral damage. In ATAAD patients with ILVA, it is common practice to clamp the left vertebral artery during surgery, which may compromise cerebral blood flow and may jeopardize both survival rates and prognostic outcomes. It also poses additional difficulties during the total arch replacement [5].
While previous studies have primarily focused on perioperative outcomes, this study specifically investigates the 18-month prognostic impact of ILVA in ATAAD patients, thereby addressing a critical gap in understanding its clinical implications.
Methods
Population and grouping
This retrospective cohort study included patients admitted to the First Affiliated Hospital of Xi’an Jiaotong University for treatment of ATAAD from January 2020 to June 2024. The diagnosis of ATAAD adheres to the American College of Cardiology’s Common Definition guidelines [6]. The exclusion criteria were as follows: (1) other comorbidities that could significantly impact prognosis, such as malignant tumors; (2) co-occurrence with other congenital arch abnormalities (such as right sided arch, aberrant right subclavian, vascular ring, bovine aortic arch, right vagal subclavian artery and so on); (3) incomplete clinical data.
Enrolled ATAAD patients were categorized into ILVA group and control group based on the presence of ILVA as determined by computed tomography angiography (CTA) preoperatively or during the operations (Fig. 1). The total arch replacement was performed firstly, followed by direct anastomosis of the ILVA to an 8-mm side branch of the prosthetic graft. During deep hypothermic circulatory arrest, bilateral antegrade cerebral perfusion was employed for brain protection. The perfusion flow rate was maintained at 6–10 mL/min/kg, and temperature was kept between 24 and 26 °C. Regional cerebral oxygen saturation was continuously monitored using near-infrared spectroscopy, and perfusion parameters were adjusted intraoperatively to ensure that regional cerebral oxygen saturation remained within ± 15% of baseline values.
Fig. 1.
Presence of ILVA on CTA in an ATAAD patient.
ILVA, isolated left vertebral artery; CTA, computed tomography angiography; ATAAD, acute Stanford type A aortic dissection.
Data collection and clinical outcomes
Anonymized clinical data were collected from the Biobank of The First Affiliated Hospital of Xi’an Jiaotong University. Demographic data, medical history, biochemical results, imaging reports, operation situations and in-hospital outcomes were collected for subsequent analysis. A propensity score matching (PSM) was employed at a 1:2 ratio, utilizing a caliper value of 0.05 to mitigate the influence of potential confounding factors such as gender, age, and surgical method. The flowchart of this study was shown in Fig. 2.
Fig. 2.
Flowchart of this study. ATAAD, acute Stanford type A aortic dissection; CTA, computed tomography angiography; ILVA, isolated left vertebral artery; PSM, propensity score matching; MACCE, major adverse cardiovascular and cerebrovascular events
The follow-up period extended from the hospitalization until either the occurrence of the primary outcome or 18 months. Follow-up data were obtained from outpatient medical records or telephone calls with patients or their relatives. The modified Rankin scale (mRS) scores were also collected to evaluate the functional outcomes and level of disability or dependence in daily activities of patients in 18-month follow-up. As a well-validated and internationally recognized tool for assessing global disability and independence in daily activities, the mRS is particularly appropriate for capturing meaningful functional recovery in the chronic phase following aortic surgery.
The primary outcome was defined as incidence of major adverse cardiovascular and cerebrovascular events (MACCE) during the 18-month postoperative follow-up period. MACCE encompassed all-cause mortality, myocardial infarction and stroke. Secondary outcomes individual components of MACCE as well as the incidence of in-hospital mortality. In the analysis of the primary outcome, the event was defined as the first occurrence of any of the three component endpoints. Secondary outcomes were assessed by analyzing each component event separately.
Statistical analysis
Continuous variables with a normal distribution were described by mean (standard deviation) and compared using the Student’s t-test. Other continuous variables were described by median and interquartile range (25th and 75th percentile) and compared using the Mann-Whitney U-test. Binary categorical variables were presented as numbers with frequency, and compared by Chi-square test or Fisher exact test. Multiple categorical variables were compared by Mann-Whitney U-test when the outcome variable was a rank variable. The incidence of MACCE and its component evens at 18-month follow-up were demonstrated by Kaplan-Meier curve and compared by log-rank test. Univariate and multivariate cox regression analysis were conducted to identify the independent risk factors for 18-month MACCE and in-hospital mortality. Variables with a P-value < 0.10 in the univariate cox regression would be included in the multivariate cox regression analyses. The hazard ratios (HR) and odds ratio (OR) with 95% confidence intervals (CI) were calculated to determine the intensity of risk factors. The statistical analyses were performed using SPSS software (version 26, IBM, Armonk, USA) and R software (version 4.4.1, R Foundation for Statistical Computing, Austria). A two-sided P value < 0.05 was considered statistically significant.
Ethical statement
This study adhered to the Declaration of Helsinki and received approval from the Ethics Committee of the First Affiliated Hospital of Xi’an Jiaotong University (XJTU1AF2024LSYY-486, Date: 2024-12-11). The Ethics Committee of the First Affiliated Hospital of Xi’an Jiaotong University waived the requirement of written informed consent due to the retrospective design.
Results
A total of 2316 ATAAD patients were included in this study. Among these, 39 (1.68%) patients were allocated to the ILVA group. Prior to PSM, the proportion of male patients and surgical methods as well as the age displayed differences (P < 0.05). Following PSM, there were still 39 patients in the ILVA group and 78 patients in the control group. There were no significant differences in the gender, age and surgical methods between the two groups after PSM (Table 1).
Table 1.
Characteristics of ILVA in ATAAD patients before and after PSM
| Characteristics | Before PSM (N = 2316) | After PSM (N = 117) | ||||
|---|---|---|---|---|---|---|
| ILVA group (n = 39) |
Control group (n = 2277) |
P | ILVA group (n = 39) |
Control group (n = 78) |
P | |
| Male (n, %) | 26 (66.7%) | 1819 (79.9%) | 0.042 | 26 (66.7%) | 52 (66.7%) | > 0.999 |
| Age, years | 60 (51, 65) | 55 (49, 62) | 0.032 | 58 (51, 65) | 58 (51, 65) | 0.999 |
| Surgical method (n, %) | < 0.001 | > 0.999 | ||||
| Sun’s | 30 (76.9%) | 1309 (57.5%) | 30 (76.9%) | 60 (76.9%) | ||
| Sun’s + Bentall | 8 (20.5%) | 266 (11.7%) | 8 (20.5%) | 16 (20.5%) | ||
| Sun’s + EVGE | 1 (2.6%) | 702 (30.8%) | 1 (2.6%) | 2 (2.6%) | ||
ATAAD acute Stanford type A aortic dissection, Sun’s Sun’s Procedure, EVGE endovascular graft exclusion, PSM propensity score matching, ILVA isolated left vertebral artery
Baseline characteristics and operation-related data
The baseline characteristics and operation-related data between two groups were presented in Table 2. Compared to the control group, the ILVA group demonstrated a greater proportion of patients with renal insufficiency [14 (35.9%) vs. 14 (17.9%), P = 0.032], but lower levels of CRP [10.00 (10.00, 41.70) vs. 27.40 (10.00, 85.68) mg/L, P = 0.012]. Regarding operation-related data, the cardiopulmonary bypass (CPB) time in the ILVA group was significantly longer than that in the control group [180 (152, 221) vs. 144 (123, 179) min, P < 0.001]. However, there was no statistical difference in total operation time and cross-clamp time between the two groups.
Table 2.
Baseline characteristics between the two groups
| Characteristics | Total (n = 117) | ILVA group (n = 39) | Control group (n = 78) | P |
|---|---|---|---|---|
| BMI, kg/m2 | 25.40 (22.64,27.34) | 24.93 (22.04,26.57) | 25.65 (23.26,27.68) | 0.307 |
| Medical history (%) | ||||
| Hypertension | 82 (71.3%) | 24 (63.2%) | 58 (75.3%) | 0.175 |
| Smoking | 57 (48.7%) | 18 (46.2%) | 39 (50.0%) | 0.695 |
| Drinking | 23 (19.7%) | 9 (23.1%) | 14 (17.9%) | 0.511 |
| CHD | 15 (12.8%) | 6 (15.4%) | 9 (11.5%) | 0.557 |
| Renal insufficiency | 28 (23.9%) | 14 (35.9%) | 14 (17.9%) | 0.032 |
| Echocardiology | ||||
| LVEF, % | 60 (58, 65) | 62 (58, 65) | 60 (56, 65) | 0.211 |
| Aortic sinus diameter, mm | 41.20 (35.00, 44.50) | 41.00 (35.00, 44.50) | 41.32 (35.00, 44.75) | 0.817 |
| Internal diameter of ascending aorta, mm | 44.95 (38.00, 48.00) | 43.33 (33.50, 50.25) | 45.95 (40.00, 48.00) | 0.185 |
| AR (%) | 56 (47.9%) | 17 (43.6%) | 39 (50.0%) | 0.513 |
| Biochemistry results | ||||
| PLT, 109/L | 165.10 (113.75, 208.00) | 160.18 (113.00, 208.00) | 167.60 (114.00 ,208.00) | 0.972 |
| WBC, 109/L | 11.83 ± 3.83 | 12.45 ± 4.78 | 11.48 ± 3.17 | 0.358 |
| NEUT%, % | 88.45 (83.28, 91.30) | 88.80 (80.10, 91.80) | 87.40 (83.45, 90.85) | 0.325 |
| CRP, mg/L | 14.10 (10.00, 63.40) | 10.00 (10.00, 41.70) | 27.40 (10.00, 85.68) | 0.012 |
| CK, U/L | 13.40 (4.00, 62.00) | 9.00 (2.80, 53.00) | 16.45 (4.75, 78.5) | 0.063 |
| CK-MB, U/L | 10.10 (4.00, 25.60) | 8.00 (2.80, 18.00) | 11.60 (4.29, 28.50) | 0.098 |
| LDH, U/L | 454.02 (232.00, 461.75) | 546.76 (246.50, 437.50) | 407.65 (229.00, 471.25) | 0.941 |
| ALB, g/L | 37.86 ± 5.40 | 39.01 ± 5.42 | 37.28 ± 5.32 | 0.102 |
| BUN, mmol/L | 7.47 (5.20, 9.29) | 7.49 (5.12, 9.38) | 7.46 (5.27, 9.08) | 0.735 |
| Cr, µmol/L | 93.91 (56.50 ,97.75) | 108.79 (61.00, 97.00) | 86.36 (53.00, 106.50) | 0.680 |
| eGFR, mL/min/1.73 m2 | 79.79 ± 27.05 | 79.32 ± 28.55 | 80.03 ± 26.45 | 0.897 |
| PT, s | 14.46 (13.50, 15.05) | 14.49 (13.60, 15.50) | 14.45 (13.50, 14.93) | 0.897 |
| APTT, s | 30.70 (28.75, 34.60) | 30.55 (27.55, 33.45) | 30.70 (29.25, 36.20) | 0.563 |
| D-dimer, mg/L | 11.90 (3.44, 23.50) | 9.5 (3.58, 23.39) | 11.96 (3.17, 23.65) | 0.906 |
| INR | 1.12 (1.05, 1.20) | 1.10 (1.06, 1.23) | 1.13 (1.05, 1.19) | 0.907 |
| Operation-related data | ||||
| Operation time, min | 445 (360, 993) | 480 (370, 884) | 410 (355, 1020) | 0.679 |
| CPB time, min | 154 (130, 189) | 180 (152, 221) | 144 (123, 179) | < 0.001 |
| Cross-clamp time, min | 91.01 (74.00, 105.00) | 97.11 (75.00, 116.50) | 88.00 (74.00, 102.00) | 0.110 |
| Lowest temperature, °C | 27.64 (26.60, 28.20) | 27.85 (27.00, 28.50) | 27.53 (26.50, 28.10) | 0.118 |
| Bilateral antegrade perfusion (%) | 116 (99.1%) | 39 (100%) | 77 (98.7%) | > 0.999 |
ILVA isolated left vertebral artery, BMI body mass index, CHD coronary heart disease, LVEF left ventricular ejection fraction, AR aortic valve regurgitation, PLT blood platelet, WBC white blood cell, NEUT neutrophil count, CRP C-reactive protein, CK creatine kinase, CK-MB creatine kinase-MB isoenzymes, LDH lactate dehydrogenase, ALB albumin, BUN blood urea nitrogen, Cr creatinine, eGFR estimated glomerular filtration rate, PT prothrombin time, APTT activated partial thromboplastin time, INR international normalized ratio, CPB cardiopulmonary bypass
In-hospital and follow-up clinical outcomes
The incidence of in-hospital mortality [9 (23.1%) vs. 6 (7.7%), P = 0.019] and stroke rates [4 (10.3%) vs. 1 (1.3%), P = 0.042] were significantly higher among patients in the ILVA group than that in the control group. Other outcomes, including the incidence of branch vessel anastomotic stenosis measured by CTA, did not show differences (Table 3).
Table 3.
In-hospital outcomes and functional status at 18-month follow-up
| Characteristics | ILVA group (n = 39) | Control group (n = 78) | P |
|---|---|---|---|
| In-hospital outcomes | |||
| ECMO (%) | 2 (5.1%) | 0 (0%) | 0.109 |
| CRRT (%) | 9 (11.5%) | 9 (23.1%) | 0.103 |
| Branch vessel anastomotic stenosis (%) | 1 (2.6%) | 4 (5.1%) | 0.664 |
| Postoperative ICU stay, days | 6.03 (3.00, 8.00) | 6.60 (2.00, 8.25) | 0.447 |
| Total in-hospital stay, days | 14.68 (7.75, 19.25) | 18.79 (14.00, 21.00) | 0.069 |
| In-hospital stroke (%) | 4 (10.3%) | 1 (1.3%) | 0.042 |
| In-hospital mortality (%) | 9 (23.1%) | 6 (7.7%) | 0.019 |
| mRS scores at 18-month follow-up | 0.406 | ||
| 0 | 17 (43.6%) | 54 (69.2%) | |
| 1 | 4 (10.3%) | 13 (16.7%) | |
| 2 | 0 (0%) | 0 (0%) | |
| 3 | 0 (0%) | 0 (0%) | |
| 4 | 0 (0%) | 2 (2.6%) | |
| 5 | 1 (2.6%) | 0 (0%) | |
| 6 | 17 (43.6%) | 9 (11.5%) | |
ILVA isolated left vertebral artery, ECMO extracorporeal membrane oxygenation, CRRT continuous renal replacement therapy, ICU intensive care unit, mRS modified Rankin scale
The median follow-up time was 18 (4, 18) months. A total of 3 patients (2.6%) were lost follow-up after discharge, all of whom were in the control group and had only completed 1 month of follow-up. The ILVA group had higher incidences of MACCE [19 (48.7%) vs. 11 (14.1%), P < 0.001], all-cause death [17 (43.6%) vs. 9 (11.5%), P < 0.001] and stroke [5 (12.8%) vs. 2 (2.6%), P = 0.018] compared with the control group in the 18-month follow-up (Fig. 3). The incidence of AMI did not reveal differences, with only one AMI event occurring in the ILVA group. There was also no significant difference in the results of mRS scores at 18-month follow-up, though the ILVA group showed higher proportion of mRS score 6. The distribution of the mRS scores were demonstrated in Fig. 4.
Fig. 3.
Kaplan-Meier curve of MACCE (a), all-cause death (b), AMI (c) and stroke (d) between ILVA group and control group at 18-month follow-up
Fig. 4.
Distribution of mRS scores between the two groups at 18 months follow-up
ILVA, isolated left vertebral artery; mRS, modified Rankin scale
Risk factors for MACCE at 18-month and in-hospital mortality
Multivariate cox regression indicated that ILVA [HR = 2.60, 95%CI: 1.17–5.80, P = 0.019], renal insufficiency [HR = 1.93, 95%CI: 1.10–3.39, P = 0.023] and CPB time [HR = 1.01, 95%CI: 1.00-1.01, P = 0.026] were independent risk factors for MACCE at 18-month in ATAAD patients (Table 4). However, while ILVA was not significantly associated with in-hospital mortality, the renal insufficiency [OR = 3.35, 95%CI: 1.20–9.36, P = 0.021] and CPB time [OR = 1.01, 95%CI: 1.00-1.02, P = 0.008] emerged as significant risk factors for in-hospital death.
Table 4.
Risk factors of MACCE at 18-month follow-up and in-hospital mortality in ATAAD patients
| Characteristics | Univariate model | Multivariate model | ||
|---|---|---|---|---|
| HR/OR (95% CI) | P value | HR/OR (95% CI) | P value | |
| MACCE 18-month follow-up | ||||
| ILVA (%) | 3.88 (1.84, 8.17) | < 0.001 | 2.60 (1.17, 5.80) | 0.019 |
| Renal insufficiency (%) | 2.34 (1.36, 4.04) | 0.002 | 1.93 (1.10, 3.39) | 0.023 |
| CRP, mg/L | 1.00 (0.99, 1.01) | 0.985 | ||
| CK, U/L | 1.00 (1.00, 1.00) | 0.510 | ||
| CK-MB, U/L | 1.01 (0.99, 1.02) | 0.454 | ||
| CPB time, min | 1.01 (1.00, 1.01) | 0.001 | 1.01 (1.00, 1.01) | 0.026 |
| In-hospital mortality | ||||
| ILVA (%) | 3.60 (1.18, 11.00) | 0.025 | 2.01 (0.59, 6.88) | 0.264 |
| Renal insufficiency (%) | 3.36 (1.34, 8.44) | 0.010 | 3.35 (1.20, 9.36) | 0.021 |
| CRP, mg/L | 1.00 (0.99, 1.01) | 0.635 | ||
| CK, U/L | 1.00 (1.00, 1.00) | 0.234 | ||
| CK-MB, U/L | 1.01 (0.99, 1.03) | 0.605 | ||
| CPB time, min | 1.01 (1.00, 1.02) | 0.005 | 1.01 (1.00, 1.02) | 0.008 |
MACCE major adverse cardiovascular and cerebrovascular events, ILVA isolated left vertebral artery, CRP C-reactive protein, CK creatine kinase, CK-MB creatine kinase-MB isoenzymes, CPB cardiopulmonary bypass, HR hazard ratio, OR odds ratio, CI confidence intervals
Discussion
This retrospective cohort study enrolled ATAAD patients and categorized them into ILVA group and control group. After an 18-month follow-up, patients in ILVA group exhibited a higher incidence of MACCE, especially the all-cause death and stroke in comparison to the control group. Furthermore, it also found that ILVA served as an independent risk factor for MACCE at 18-month but not for in-hospital mortality among ATAAD patients. These findings suggested that ILVA might serve as a marker for cardiovascular risk, but not for early postoperative mortality.
ILVA is characterized as a branching variant where the left vertebral artery originates directly from the aortic arch, positioned either proximal or distal to the left subclavian artery. In the general population, ILVA represents the second most common anatomical variation of the superior aortic trunk [7]. The vertebral artery enters into the posterior circulation by connecting with both the Willis circle and communicating with branches of the posterior cerebral artery, which primarily supplies blood to the cerebellar and brainstem tissues. Dysplasia of this vessel can lead to inadequate blood supply following cerebral ischemia [8]. If there is deviation of the vertebrobasilar artery shaft towards the left side, coupled with incomplete formation of the Willis arterial circle, improper ILVA management may result in cerebral ischemia and infarction, which significantly threatens the prognosis. Patients diagnosed with ATAAD typically require emergency surgical intervention, leaving insufficient time for definitive assessment of ILVA or other vascular anomalies prior to surgery. Consequently, ILVA may only be identified intraoperatively. A recent report indicate that the general probability of complete circle of Willis was 42%, and only 27% of the Chinese populations possess a complete Willis circle [9, 10]. Therefore, evaluating how ILVA impacts brainstem perfusion dynamics and integrity of Willis circle is crucial before surgery [11, 12]. Safeguarding against potential complications associated with ILVA during total arch replacement is also imperative.
The presence of ILVA complicates the aortic arch surgery, not only due to its anatomical variations, the smaller diameters of left-sided vertebral arteries present additional challenges related to vascular remodeling [13]. The existence of ILVA significantly impacts both the reconstruction technique employed for the aortic arch and the cerebral protection methods utilized during surgery. Given that routine replacement of the aortic arch involves infusing three branches, any ILVA directly originates from the arch is simply clamped without perfusion. Hemodynamic studies found that in cases where there is reconstruction of the left subclavian artery within intrathoracic blood vessels following aortic repair on the left side, there is a significant decrease in consequent blood flow. Additionally, peak contraction velocity in the left vertebral artery decreases markedly, while incidents of retrograde flow increase. Follow-up over three years post-surgery has demonstrated that this may cause the formation of embolism, and subsequent stroke [14]. Consequently, dysplasia ILVA presents greater risks for cerebral ischemia injury during surgical procedures and revascularization efforts. Although current research regarding prognosis after ILVA revascularization primarily stems from case reports and small clinical reviews, it often indicates poor outcomes associated with this condition.
Given that the Willis circles are often incomplete in the general population, improper management of ILVA during aortic surgery may compromise posterior cerebral circulation and result in serious neurological complications [15]. Previous reports on the neurological risk associated with ILVA have yielded mixed results. One study described a small series of 9 ATAAD patients with ILVA and reported no neurological complications attributable to arch vessel abnormalities [16]. However, this study was limited by its small sample size and focus on immediate postoperative outcomes, rendering it underpowered to detect differences in stroke risk. In contrast, another study showed that among 25 ATAAD patients with ILVA, in-hospital mortality and neurological complications rates were 8% and 16%, respectively [17]. Similarly, Qi et al. included 21 patients with acute aortic dissection involving ILVA, all of whom underwent surgical repair with intentional ILVA reconstruction using various techniques based on anatomical proximity. Despite these revascularization efforts, 5 patients experienced postoperative neurological deficits—including spinal cord injury, limb weakness, paraplegia, or transient neurologic deficit—though all recovered during follow-up. The authors emphasized that timely ILVA reconstruction was essential, yet their data also suggested that this high-risk anatomy may remain vulnerable even after technical success [18]. Consistent with these findings, our study demonstrated that ATAAD patients with ILVA had a significantly higher incidence of stroke than the control group, both in hospital and during the follow-up, suggesting that the associated risk may extend beyond the acute perioperative period. The higher risk of MACCE in 18-month also indicated that ILVA-related risks are likely driven not by acute graft failure, but by chronic hemodynamic insufficiency, potentially due to compromised posterior circulation reserve, chronic anastomotic stenosis following surgical repair or recurrent microembolic events from turbulent flow. These findings underscored the necessity for heightened attention towards revascularization strategies and cerebral perfusion management in ATAAD patients with ILVA to mitigate potential neurological complications.
Despite widespread recognition regarding the critical role of vertebral artery in cerebral circulation, clear guidelines addressing this particular issue remain lacking, and its management during aortic surgery has been controversial [4, 19]. For cases with ILVA, enhanced CTA of head and neck is encouraged prior to aortic repair to assess vertebral artery dominance and the integrity of the Willis circle if time permits. Yang et al. demonstrated a technique involving the transposition of the artery to the carotid artery, while maximizing preservation of the vertebral artery in patients with normal anatomical configurations. This approach may reduce the incidence of neurologic deficits, bypass occlusion, or ILVA stenosis, offering protective benefits for ILVA patients [20]. Zhang et al. also compared 3 revascularization strategies for ILVA during zone-2 thoracic endovascular aortic repair, including a novel chimney with the right brachial-left brachial through and through procedure, in vitro fenestration, and transposition. Despite all patients maintaining antegrade flow in the ILVA, the rates of new neurological symptoms differed across groups—0% in the novel procedure group, 8% in the fenestration group, and 33% in the transposition group during a mean follow-up of 63.6 ± 4.0 months [21]. These findings highlight that even with successful revascularization, the choice of strategy may influence cerebrovascular outcomes in ILVA patients. While the novel procedure demonstrated promising midterm outcomes, its applicability to ATAAD remains uncertain. In our practice, total arch replacement is routinely performed first, followed by direct anastomosis of the ILVA to an 8-mm side branch of the prosthetic graft. Bilateral antegrade cerebral perfusion is employed throughout deep hypothermic circulatory arrest, with strict monitoring of regional cerebral oxygen saturation and minimization of circulatory arrest duration. Notably, despite these comprehensive cerebral protection measures, ILVA patients still exhibit a significantly higher stroke rate—highlighting the need for tailored strategies in perioperative and postoperative management.
Furthermore, this study identified ILVA, renal insufficiency and CPB time as independent risk factors for incidence of MACCE at 18-month follow-up. Although baseline renal insufficiency and CPB time were not fully balanced after PSM, they were retained as covariates in the multivariable models to avoid over-adjustment for potential mediators on the causal pathway between ILVA anatomy and adverse outcomes. The consistent association of CPB time with increased risks underscored the importance of surgical efficiency and minimizing extracorporeal circulation duration. Moreover, preoperative assessment and optimization of renal function were essential for improving overall prognosis in ATAAD patients. Generally, these risk factors underscore the importance for clinicians to monitor relevant indicators in ATAAD patients with ILVA to improve prognosis. More attempts are warranted to explore revascularization strategies for ILVA and to address the prognostic challenging in this clinical setting.
There are some limitations in this study. Firstly, this is a single-center retrospective study. Despite the use of PSM, residual confounding from unmeasured factors-such as finer details of aortic dissection extent and surgeon experience variability-may persist and potentially influence the observed outcomes. Secondly, given the loss of follow-up in some patients, potential biases may arise. Thirdly, the relatively small sample size limits the generalizability and statistical power of our findings. Additionally, our findings—particularly the significantly higher MACCE rates in ILVA patients in an 18-month follow-up—appeared to diverge from several prior studies.
Future research should include larger, multicenter prospective studies with scheduled postoperative imaging—such as CTA at 6 and 12 months—to systematically evaluate anastomotic patency and posterior circulation perfusion in ILVA patients. Meanwhile, comparative effectiveness analyses of different revascularization strategies are also essential, as they may help identify the optimal surgical approach for prognosis—particularly stroke prevention—in patients with ILVA.
Conclusions
This study enrolled ATAAD patients and separated them into ILVA and control group. The results indicated that the incidence of MACCE at 18-month follow-up was higher in ATAAD patients with ILVA, especially the incidence of all-cause death and stroke. ILVA, as well as renal insufficiency and CPB time, was identified as risk factors for 18-month MACCE, but not for in-hospital mortality in ATAAD patients. ILVA might serve as a marker for cardiovascular risk, but not for early postoperative mortality. Special attention should be attached to ATAAD patients with ILVA, and novel revascularization strategies for ILVA patients are also warranted to improve the long-term prognosis.
Acknowledgements
We are grateful to the Biobank of the First Affiliated Hospital of Xi’an Jiaotong University for providing clinical data.
Prior presentation
The abstract of this study was presented in the European Society of Cardiology Congress 2025 organized by the European Society of Cardiology, taking place from 29 August to 1 September 2025 in Madrid, Spain.
Abbreviations
- ATAAD
Acute Stanford type A aortic dissection
- ILVA
Isolated left vertebral artery
- PSM
Propensity score matching
- MACCE
Major adverse cardiovascular and cerebrovascular events
- CPB
Cardiopulmonary bypass
- CTA
Computed tomography angiography
- mRS
Modified Rankin scale
- HR
Hazard ratios
- OR
Odds ratios
- CI
Confidence intervals
Authors’ contributions
All named authors contributed to the conceptualization of the study and critically reviewed the manuscript. L.Y. and C.Z. performed the formal analysis and wrote the original draft. Y.Y. provided overall supervision of the project. All authors reviewed the manuscript.
Funding
This study was supported by the Clinical Research Award of the First Affiliated Hospital of Xi’an Jiaotong University (XJTU1AF2021CRF-005 and XJTU1AFCRF2023-XK006).
Data availability
The datasets generated and analyzed during the current study are not publicly available due to ethical restrictions, but are available from the corresponding author on reasonable request.
Declarations
Ethics approval and consent to participate
This study adhered to the Declaration of Helsinki and received approval from the Ethics Committee of the First Affiliated Hospital of Xi’an Jiaotong University (XJTU1AF2024LSYY-486, Date: 2024-12-11). The Ethics Committee of the First Affiliated Hospital of Xi’an Jiaotong University waived the requirement of written informed consent due to the retrospective design.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Luqin Yan and Changying Zhao contributed equally to this work and shared the first authorship.
References
- 1.Ma L, Chai T, Yang X, Zhuang X, Wu Q, Chen L, Qiu Z. Outcomes of hemi- vs. total arch replacement in acute type A aortic dissection: A systematic review and meta-analysis. Front Cardiovasc Med. 2022;9:988619. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Popieluszko P, Henry BM, Sanna B, Hsieh WC, Saganiak K, Pękala PA, Walocha JA, Tomaszewski KA. A systematic review and meta-analysis of variations in branching patterns of the adult aortic arch. J Vasc Surg. 2018;68(1):298–e306210. [DOI] [PubMed] [Google Scholar]
- 3.Aboulhoda BE, Ahmed RK, Awad AS. Clinically-relevant morphometric parameters and anatomical variations of the aortic arch branching pattern. Surg Radiol Anat. 2019;41(7):731–44. [DOI] [PubMed] [Google Scholar]
- 4.Asai T. Commentary: how to transpose the isolated left vertebral artery in hybrid thoracic endovascular aortic repair. J Thorac Cardiovasc Surg. 2020;159(6):2199. [DOI] [PubMed] [Google Scholar]
- 5.Zuo Y, Zhou ZC, Ge JJ. Prior reconstruction of an isolated left vertebral artery for Stanford type A aortic dissection. Eur J Cardiothorac Surg. 2021;59(6):1339–41. [DOI] [PubMed] [Google Scholar]
- 6.Isselbacher EM, Preventza O, Hamilton Black J 3rd, Augoustides JG, Beck AW, Bolen MA, Braverman AC, Bray BE, Brown-Zimmerman MM, Chen EP, et al. 2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American heart Association/American college of cardiology joint committee on clinical practice guidelines. Circulation. 2022;146(24):e334–482. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Dumfarth J, Chou AS, Ziganshin BA, Bhandari R, Peterss S, Tranquilli M, Mojibian H, Fang H, Rizzo JA, Elefteriades JA. Atypical aortic arch branching variants: A novel marker for thoracic aortic disease. J Thorac Cardiovasc Surg. 2015;149(6):1586–92. [DOI] [PubMed] [Google Scholar]
- 8.Katsanos AH, Kosmidou M, Kyritsis AP, Giannopoulos S. Is vertebral artery hypoplasia a predisposing factor for posterior circulation cerebral ischemic events? A comprehensive review. Eur Neurol. 2013;70(1–2):78–83. [DOI] [PubMed] [Google Scholar]
- 9.Li Q, Li J, Lv F, Li K, Luo T, Xie P. A multidetector CT angiography study of variations in the circle of Willis in a Chinese population. J Clin Neurosci. 2011;18(3):379–83. [DOI] [PubMed] [Google Scholar]
- 10.Krabbe-Hartkamp MJ, van der Grond J, de Leeuw FE, de Groot JC, Algra A, Hillen B, Breteler MM, Mali WP. Circle of willis: morphologic variation on three-dimensional time-of-flight MR angiograms. Radiology. 1998;207(1):103–11. [DOI] [PubMed] [Google Scholar]
- 11.Tasdemir R, Cihan ÖF, Ince R, Sevmez F. Anatomical variations in aortic arch branching pattern: A computed tomography angiography study. Cureus. 2023;15(3):e36731. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Tasdemir R, Cihan OF. Multidetector computed tomography evaluation of origin, V2 segment variations and morphology of vertebral artery. Folia Morphol (Warsz). 2023;82(2):274–81. [DOI] [PubMed] [Google Scholar]
- 13.Czerny M, Schmidli J, Adler S, van den Berg JC, Bertoglio L, Carrel T, Chiesa R, Clough RE, Eberle B et al. Etz C’s Choice - Current Options and Recommendations for the Treatment of Thoracic Aortic Pathologies Involving the Aortic Arch, editors. An Expert Consensus Document of the European Association for Cardio-Thoracic Surgery (EACTS) & the European Society for Vascular Surgery (ESVS). Eur J Vasc Endovasc Surg. 2019;57(2):165–198. [DOI] [PubMed] [Google Scholar]
- 14.Kamman AV, Eliason JL, Williams DM, Yang B, Moll FL, Trimarchi S, Eagle KA, Patel HJ. Impact of left subclavian artery revascularization before thoracic endovascular aortic repair on postoperative cerebrovascular hemodynamics. Ann Vasc Surg. 2018;46:307–13. [DOI] [PubMed] [Google Scholar]
- 15.Piffaretti G, Gelpi G, Tadiello M, Ferrarese S, Socrate AM, Tozzi M, Bellosta R. Transposition of the left vertebral artery during endovascular stent-graft repair of the aortic arch. J Thorac Cardiovasc Surg. 2020;159(6):2189–e21982181. [DOI] [PubMed] [Google Scholar]
- 16.Suzuki K, Kazui T, Bashar AH, Yamashita K, Terada H, Washiyama N, Suzuki T. Total aortic arch replacement in patients with arch vessel anomalies. Ann Thorac Surg. 2006;81(6):2079–83. [DOI] [PubMed] [Google Scholar]
- 17.Yamamoto T, Kimura N, Hori D, Mieno M, Shiraishi M, Okamura H, Kawahito K, Yamaguchi A. Morphological characteristics and outcomes of aortic repair of acute type A aortic dissection occurring in patients with aortic arch branching variants. Surg Today. 2025;55(3):414-424. [DOI] [PubMed]
- 18.Qi R, Sun L, Zhu J, Liu Y, Zheng J, Li C, Chang Q. Total arch replacement in patients with aortic dissection with an isolated left vertebral artery. Ann Thorac Surg. 2013;95(1):36–40. [DOI] [PubMed] [Google Scholar]
- 19.Sun LZ, Qi RD, Chang Q, Zhu JM, Liu YM, Yu CT, Lv B, Zheng J, Tian LX, Lu JG. Is total arch replacement combined with stented elephant trunk implantation justified for patients with chronic Stanford type A aortic dissection? J Thorac Cardiovasc Surg. 2009;138(4):892–6. [DOI] [PubMed] [Google Scholar]
- 20.Yang G, Chen H, Sun G, Lou W, Chen X, Zhang L. Transposition of isolated left vertebral artery in hybrid thoracic endovascular aortic repair. Front Cardiovasc Med. 2021;8:783656. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Zhang H, Feng J, Guo M, Liu J, Xu D, Lu Y, Zhu H, Liu M, Feng R. Management of an isolated left vertebral artery on the arch during zone 2 landing thoracic endovascular aortic repair: A multicentre retrospective study. Eur J Vasc Endovasc Surg. 2023;65(3):330–7. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets generated and analyzed during the current study are not publicly available due to ethical restrictions, but are available from the corresponding author on reasonable request.