Preoperative proteinuria is independently associated with mortality after fenestrated endovascular aneurysm repair.

OBJECTIVE: Fenestrated endovascular aneurysm repair (FEVAR) has become a mainstay in treating complex aortic aneurysms, though baseline patient factors predicting long-term outcomes remain poorly understood. Proteinuria is an early marker for chronic kidney disease and associated with adverse cardiovascular outcomes, but its utility in patients with aortic aneurysms is unknown. We aimed to determine whether preoperative proteinuria impacts long-term survival after FEVAR. METHODS: A single-institution, retrospective review of all elective FEVAR was performed. Preoperative proteinuria was assessed by urinalysis: negative (0-29 mg/dL), 1+ (30-100 mg/dL), 2+ (101-299 mg/dL), and 3+ (≥300 mg/dL). The cohort was stratified by patients with proteinuria (≥30 mg/dL) vs those without (<30 mg/dL). Baseline, perioperative, and long-term outcomes were compared. The primary outcome, all-cause mortality, was evaluated by Kaplan-Meier analysis and independent predictors with Cox proportional hazards modeling. RESULTS: Among 181 patients who underwent standard FEVAR from 2012 to 2022 (mean follow-up 33 months), any proteinuria was noted in 30 patients (16.6%). Patients with proteinuria were more likely to be Black (10.0% vs 1.3%) with a lower estimated glomerular filtration rate (eGFR) (52.7 ± 24.7 vs 67.7 ± 20.5 mL/min/1.73 m2), higher Society for Vascular Surgery comorbidity score (10.9 ± 4.3 vs 8.2 ± 4.7) and calcium channel blocker therapy (50.0% vs 29.1%), and larger maximal aneurysm diameter (67.2 ± 16.9 vs 59.8 ± 9.8 mm) (all P < .05). Thirty-day mortality was higher in the proteinuria group (10.0% vs 1.3%; P = .03). Overall survival at 1 and 5 years was significantly lower for those with proteinuria (71.5% vs 92.3% and 29.5% vs 68.1%; log-rank P < .001). On multivariable analysis, preoperative proteinuria was independently associated with over threefold higher hazard of mortality (hazard ratio [HR]: 3.21, 95% confidence interval [CI]: 1.66-6.20; P < .001), whereas preoperative eGFR was not predictive (HR: 0.99, 95% CI: 0.98-1.01; P = .28). Additional significant predictors included chronic obstructive pulmonary disease (HR: 2.04), older age (HR: 1.05), and larger maximal aneurysm diameter (HR: 1.03; all P < .05). CONCLUSIONS: In our 10-year experience with FEVAR, preoperative proteinuria was observed in 17% of patients and was significantly associated with worse survival. In this cohort, proteinuria was independently associated with all-cause mortality, whereas eGFR was not, suggesting that urinalysis may provide an additional simple metric for risk-stratifying patients before FEVAR.

Reinterventions and sac dynamics after fenestrated endovascular aortic repair with physician-modified endografts for index aneurysm repair and following proximal failure of prior endovascular aortic repair.

OBJECTIVE: The high frequency of reinterventions after fenestrated endovascular aortic repair (FEVAR) with physician-modified endografts (PMEGs) has been well-studied. However, the impact of prior EVAR on reinterventions and sac behavior following these procedures remains unknown. We analyzed 3-year rates of reinterventions and sac dynamics following PMEG for index aneurysm repair compared with PMEG for prior EVAR with loss of proximal seal. METHODS: We performed a retrospective analysis of 122 consecutive FEVARs with PMEGs at a tertiary care center submitted to the United States Food and Drug Administration in support of an investigational device exemption trial. We excluded patients with aortic dissection (n = 5), type I to III thoracoabdominal aneurysms (n = 13), non-elective procedures (n = 4), and prior aortic surgery other than EVAR (n = 8), for a final cohort of 92 patients. Patients were divided into those who underwent PMEG for index aneurysm repair (primary FEVAR) and those who underwent PMEG for rescue of prior EVAR with loss of proximal seal (secondary FEVAR). The primary outcomes were freedom from reintervention and sac dynamics (regression as ≥5 mm decrease, expansion as ≥5 mm increase, and stability as <5 mm increase or decrease) at 3 years. Secondary outcomes were perioperative mortality and 3-year survival. RESULTS: Of the 92 patients included, 56 (61%) underwent primary FEVAR and 36 (39%) underwent secondary FEVAR. Secondary FEVAR patients were older (78 years [interquartile range (IQR), 74.5-83.5 years] vs 73 years [IQR, 69-78.5 years]; P < .001), more frequently male (86% vs 68%; P = .048), and had larger aneurysms (72.5 mm [IQR, 65.5-81 mm] vs 59 mm [IQR, 55-65 mm]; P < .001). Perioperative mortality was 1.8% for primary FEVAR and 2.7% for secondary FEVAR (P = .75). At 3 years, overall survival was 84% for primary FEVAR and 71% for secondary FEVAR (P = .086). Freedom-from reintervention was significantly higher for primary FEVAR than secondary FEVAR, specifically 82% vs 38% at 3 years (P < .001). Primary FEVAR also had more desirable sac dynamics relative to secondary FEVAR at 3 years (primary: 54% stable, 46% regressed, 0% expanded vs secondary: 33% stable, 28% regressed, and 39% expanded; P = .038). CONCLUSIONS: FEVAR for primary aortic repair and FEVAR for rescue of prior EVAR with loss of proximal seal are two distinct entities. Following primary FEVAR, less than a quarter of patients have undergone reintervention at 3 years, and sac expansion was not seen in our cohort. Comparatively, 3 years after secondary FEVAR, over one-half of patients have undergone reintervention and over one-third have had ongoing sac expansion. Vigilant surveillance and a low threshold for further interventions are crucial following secondary FEVAR.

Contemporary outcomes for arterial reconstruction with non-saphenous vein cryo-preserved conduits.

OBJECTIVE: Cryopreserved (CP) products are utilized during challenging cases when autogenous or prosthetic conduit use is not feasible. Despite decades of experience with cadaveric greater saphenous vein (GSV), there is limited available data regarding the outcomes and patency of other CP products, specifically arterial and deep venous grafts. This study was designed to evaluate outcomes of non-GSV CP conduits in patients undergoing urgent, emergent, and elective arterial reconstruction at our institution. We hypothesized that non-GSV CP allografts have adequate patency and outcomes and are therefore a feasible alternative to GSV in settings where autologous graft is unavailable or prosthetic grafts are contraindicated. METHODS: This study was approved by the Institutional Review Board at our institution. We retrospectively reviewed charts of patients undergoing arterial reconstructions using CP conduits from 2010 to 2022. Data collected included demographics, comorbidities, smoking status, indications for surgery, indication for CP conduit use, anatomic reconstruction, urgency of procedure, and blood loss. Time-to-event outcomes included primary and secondary graft patency rates, follow-up amputations, and mortality; other complications included follow-up infection/reinfection and 30-day complications, including return to the operating room and perioperative mortality. Time-to-event analyses were evaluated using product-limit survival estimates. RESULTS: Of 96 identified patients receiving CP conduits, 56 patients received non-GSV conduits for 66 arterial reconstructions. The most common type of non-GSV CP product used was femoral artery (31 patients), followed by aorto-iliac artery (22 patients), and femoral vein (19 patients), with some patients receiving more than one reconstruction or CP product. Patients were mostly male (75%), with a mean age of 63.1 years and a mean body mass index of 26.7 kg/m2. Indications for CP conduit use included infection in 53 patients, hostile environment in 36 patients, contaminated field in 30 patients, tissue coverage concerns in 30 patients, inadequate conduit in nine patients, and patient preference in one patient. Notably, multiple patients had more than one indication. Most surgeries (95%) were performed in urgent or emergent settings. Supra-inguinal reconstructions were most common (53%), followed by extra-anatomic bypasses (47%). Thirty-day mortality occurred in 10 patients (19%). Fifteen patients (27%) required return to the operating room for indications related to the vascular reconstructions, with 10 (18%) cases being unplanned and five (9%) cases planned/staged. Overall survival at 6, 12, and 24 months was 80%, 68%, and 59%, respectively. Primary patency at 6, 12, and 24 months was 86%, 70%, and 62%, respectively. Amputation freedom at 6 months, 12 months, and 24 months was 98%, 95%, and 86%, respectively for non-traumatic indications. CONCLUSIONS: Non-GSV CP products may be used in complex arterial reconstructions when autogenous or prosthetic options are not feasible or available.

Predictors of amputation-free survival and wound healing after infrainguinal bypass with alternative conduits.

OBJECTIVE: Inadequate vein quality or prior harvest precludes use of autologous single segment greater saphenous vein (ssGSV) in many patients with chronic limb-threatening ischemia (CLTI). Predictors of patient outcome after infrainguinal bypass with alternative (non-ssGSV) conduits are not well-understood. We explored whether limb presentation, bypass target, and conduit type were associated with amputation-free survival (AFS) after infrainguinal bypass using alternative conduits. METHODS: A single-center retrospective study (2013-2020) was conducted of 139 infrainguinal bypasses performed for CLTI with cryopreserved ssGSV (cryovein) (n = 71), polytetrafluoroethylene (PTFE) (n = 23), or arm/spliced vein grafts (n = 45). Characteristics, Wound, Ischemia, and foot Infection (WIfI) stage, and outcomes were recorded. Multivariable Cox proportional hazards and classification and regression tree analysis modeled predictors of AFS. RESULTS: Within 139 cases, the mean age was 71 years, 59% of patients were male, and 51% of cases were nonelective. More patients undergoing bypass with cryovein were WIfI stage 4 (41%) compared with PTFE (13%) or arm/spliced vein (27%) (P = .04). Across groups, AFS at 2 years was 78% for spliced/arm, 79% for PTFE, and 53% for cryovein (adjusted hazard ratio for cryovein, 2.5; P = .02). Among cases using cryovein, classification and regression tree analysis showed that WIfI stage 3 or 4, age >70 years, and prior failed bypass were predictive of the lowest AFS at 2 years of 36% vs AFS of 58% to 76% among subgroups with less than two of these factors. Although secondary patency at 2 years was worse in the cryovein group (26% vs 68% and 89% in arm/spliced and PTFE groups; P < .01), in patients with tissue loss there was no statistically significant difference in wound healing in the cryovein group (72%) compared with other bypass types (72% vs 87%, respectively; P = .12). CONCLUSIONS: In patients with CLTI lacking suitable ssGSV, bypass with autogenous arm/spliced vein or PTFE has superior AFS compared with cryovein, although data were limited for PTFE conduits for distal targets. Despite poor patency with cryovein, wound healing is achieved in a majority of cases, although it should be used with caution in older patients with high WIfI stage and prior failed bypass, given the low rates of AFS.

Covered endovascular reconstruction of the aortic bifurcation: A systematic review aggregated data and individual participant data meta-analysis.

BACKGROUND: We investigated the early and midterm efficacy and safety of covered endovascular reconstruction of the aortic bifurcation (CERAB) in the treatment of aortoiliac disease (AID). METHODS: A systematic search on PubMed, Scopus, and Web of Science for articles published by August 2023 was performed. The primary end points were primary patency and secondary patency. RESULTS: Eleven retrospective case series, involving 579 patients, were incorporated in the review with 88.9% of the included lesions being categorized as Trans-Atlantic Inter-Society Consensus (TASC) C or D. The pooled primary patency estimates at 12, 24 and 36 months were 94.4% (95% confidence interval [CI], 89.4-99.7), 84.4% (95% CI, 72.3-98.5) and 83.8% (95% CI, 71.4-98.3) respectively. The mean primary patency time, representing the period during which individuals remained event-free, was 51.9 months (95% CI, 43.6-55.4). The pooled 36 months primary patency for studies with a predominantly claudicant patient population (>75% of patients) was 89.4% (95% CI, 78.5-100.0), compared with 71.5% (95% CI, 45.6-100.0) for studies with a mixed population (50% of patients). The pooled 36 months primary patency for studies with a predominantly TASC D patient population (>82% of patients) was 70.4% (95% CI, 46.4-100.0) compared with 91.0% (95% CI, 79.1-100.0) for studies with a more homogenous cohort. The pooled secondary patency estimates at 12, 24, and 36 months were 98.6% (95% CI, 96.2-100.0), 97% (95% CI, 93.1-100.0), and 97% (95% CI, 93.1-100.0), respectively. The pooled technical success, 30-day mortality and 30-day systemic complications estimates were 95.9% (95% CI, 93.7- 97.4), 1.9% (95% CI, 1.0-3.5), and 6.4% (95% CI, 4.4-9.1), respectively. The pooled intraoperative and postoperative 30-day CERAB-related complications estimates were 7.3% (95% CI, 2.0-23.0) and 4.2% (95% CI, 0.7-21.0), respectively. The pooled major amputation and target lesion reinterventions by the end of follow-up were 1.9% (95% CI, 1.0-3.4) and 13.9% (95% CI, 9.9-19.2), respectively. The pooled access site complication estimate was 11.7% (95% CI, 5.9-21.7). CONCLUSIONS: Although this review has showcased the safety and feasibility of the CERAB technique in treating AID, it has also highlighted the necessity for a close and prolonged follow-up period extending beyond 1 year. Moreover, the favorable secondary patency estimates predominantly attained via endovascular reinterventions emphasize a potentially advantageous characteristic of the CERAB technique, particularly valuable when addressing late-stage AID disease or anatomically complex lesions.

Adoption and clinical outcomes of fenestrated endovascular aneurysm repair in a regional, multistate community hospital system.

OBJECTIVE: Complex endovascular abdominal aortic aneurysm (AAA) repair techniques have evolved over the last decade, yet patterns of physician and hospital system adoption of fenestrated endovascular aneurysm repair (FEVAR) remain poorly defined. We investigated clinical outcomes, use trends, and surgeon and hospital experience for FEVAR in a large community hospital system. METHODS: We conducted a retrospective cohort study of all FEVAR procedures within our 5-state hospital system between April 2012 and June 2021. AAA repair volumes (open, EVAR, and FEVAR) were captured at the hospital and surgeon levels using Current Procedural Terminology and International Classification of Diseases codes. Clinical and outcomes data were collected for FEVAR patients. To consider if surgeon or hospital experience influenced outcomes, sequential case number was used to divide patients into surgeon experience and hospital experience groups. Inverse probability weighted and generalized linear mixed models, adjusted for demographics and comorbidities, were built to examine risk-adjusted outcomes for surgeon and hospital experience groups. RESULTS: Of 3850 patients treated with AAA procedures of any kind between 2012 and 2021, 160 (4.2%) underwent FEVAR. FEVAR procedures were performed by 34 different surgeons at 12 hospitals, with intraoperative complications and unplanned adjunctive procedures occurring in 18.8% (n = 30) and 19.4% (n = 31) of patients, respectively. Among FEVAR patients, in-hospital mortality was 1.3% (n = 2) and postoperative morbidity was 16.9% (n = 27). Renal function decline occurred postoperatively in 5.1% of patients. Early (<30 day) postoperative endoleaks occurred in 15.3% of patients (n = 21). Target vessel patency was 95.6% on initial postoperative imaging. Surgeon and hospital experience had a small positive impact on outcomes after the first one to three cases. Significant decreases in operative time, fluoroscopy time, and estimated blood loss were observed with increased surgeon experience, relative to a surgeon's first case (P < .05). There were lower odds of intraoperative complications after a surgeon's first case (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.03-0.77, for cases 2-3) or after a hospital's first one to three cases (OR, 0.19; 95% CI, 0.04-0.89, for cases 4-8; OR, 0.12; 95% CI, 0.03-0.55 for cases 9-49). CONCLUSIONS: Clinical outcomes of FEVAR across our hospital system compare favorably with previously published reports. Although system-wide FEVAR adoption increased 3-fold over the last decade, FEVAR continued to be performed by a minority of hospitals in our system. The results from this cohort demonstrate low rates of adverse events, high rates of technical efficiency, and a small impact of surgeon and hospital experience, thereby supporting this advanced endovascular technology as a safe, efficacious, and generalizable treatment alternative to open repair for patients with complex aortic anatomy.

Follow-up compliance in patients undergoing abdominal aortic aneurysm repair at Veterans Affairs hospitals.

OBJECTIVE: The Society for Vascular Surgery guidelines recommend annual imaging surveillance following endovascular aneurysm repair (EVAR) and every 5 years following open surgical repairs (OSR) of abdominal aortic aneurysms (AAAs). Adherence to these guidelines is low outside of clinical trials, and compliance at Veterans Affairs (VA) hospitals is not yet well-established. We examined imaging follow-up compliance and mortality rates after AAA repair at VA hospitals. METHODS: We queried the VA Surgical Quality Improvement Program database for elective infrarenal AAA repairs, EVAR and OSR, then merged in follow-up imaging and mortality information. Mortality rate over time was derived using Kaplan-Meier estimation. Generalized estimating equation with a logit link and a sandwich standard error estimate was performed to compare the probability of having annual follow-up imaging over time between procedure types and to identify variables associated with follow-up imaging for EVAR patients. RESULTS: Our analysis included 11,668 patients who underwent EVAR and 4507 patients who underwent OSR at VA hospitals between the years 2000 and 2019. The 30-day mortality rate for EVAR and OSR was 0.37% and 0.82%, respectively. OSR was associated with lower long-term mortality after adjusting age, sex, American Society of Anesthesiologists classification and preoperative renal failure with an adjusted hazard ratio of 0.88 (95% confidence interval, 0.84-0.92; P < .01). Of surviving patients, the follow-up imaging rate was 69.1% by 1 year post-EVAR. The follow-up rate after 5 years was 45.6% post-EVAR compared with 63.6% post-OSR of surviving patients. A history of smoking or drinking, baseline hypertension, and known cardiac disease were independently associated with poor follow-up after EVAR. CONCLUSIONS: Patients undergoing elective open AAA repair in the VA hospital system had lower long-term mortality compared with patients who underwent endovascular repair. Compliance with post-EVAR imaging is low. Patient factors associated with poor post-EVAR imaging surveillance were smoking within the last year, excess alcohol consumption, and cardiac risk factors including hypertension, prior myocardial infarction, and congestive heart failure.

Preoperative risk score for mortality within 3 years of visceral segment fenestrated endovascular aortic repair.

OBJECTIVE: The purpose of this study was to create a risk score for the event of mortality within 3 years of complex fenestrated visceral segment endovascular aortic repair utilizing variables existing at the time of preoperative presentation. METHODS: After exclusions, 1916 patients were identified in the Vascular Quality Initiative who were included in the analysis. The first step in development of the risk score was univariable analysis for the primary outcome of mortality within 3 years of surgery. χ2 analysis was performed for categorical variables, and comparison of means with independent Student t-test was performed for ordinal variables. Variables that achieved a univariable P value less than 0.1 were then placed into Cox regression multivariable time dependent analysis for the development of mortality within 3 years. Variables that achieved a multivariable significance of less than 0.1 were utilized for the risk score, with point weighting based on the beta-coefficient. Variables with a beta coefficient of 0.25 to 0.49 were assigned 1 point, 0.5 to 0.74 2 points, 0.75 to 0.99 3 points, and 1.0 to 1.25 4 points. A cumulative score for each patient was then summed, the percentage of patients at each score experiencing mortality within 3 weeks was then calculated, and a comparison of score outcomes was conducted with binary logistic regression. Area under the curve analysis was performed. RESULTS: The primary outcome of mortality within 3 years of surgery occurred in 12.8% of patients (245/1916). The mean age for the study population was 73.35 years (standard deviation [SD], 8.26 years). The mean maximal abdominal aortic aneurysm (AAA) diameter was 60.43 mm (SD, 10.52 mm). The mean number of visceral vessels stented was 3.3 (SD, 0.76). Variables present at the time of surgery that were included in the risk score were: hemodialysis (3 points); age >87, chronic obstructive pulmonary disease, hypertension, AAA diameter >77 mm (all 2 points); and body mass index <20 kg/m2, female sex, congestive heart failure, active smoking, chronic renal insufficiency, age 80 to 87 years, and AAA diameter 67 to 77 mm (all 1 point). BMI >30 kg/m2 (mean, 34.46 kg/m2) and age <67 years were protective (-1 point). Testing the model resulted in an area under the curve of 0.706. Hosmer and Lemeshow goodness of fit test for logistic regression utilizing the 15 different risk score total groups revealed a model predictive accuracy of 87.3%. Significant escalations in 3-year mortality were noted to occur at scores of 6 and greater. Mean AAA diameter was significantly larger for patients who had higher risk scores (P < .001). CONCLUSIONS: A novel risk score for mortality within 3 years of fenestrated visceral segment aortic endograft has been developed that has excellent accuracy in predicting which patients will survive and derive the strongest benefit from intervention. This facilitates risk-benefit analysis and counseling of patients and families with realistic long-term expectations. This potentially enhances patient-centered decision-making.

Outcomes of post-implantation syndrome after endovascular repair for Stanford type B aortic dissection.

OBJECTIVE: The aim of this study was to investigate the correlation between post-implantation syndrome (PIS) and long-term prognosis in patients with Stanford type B aortic dissection (TBAD) undergoing thoracic endovascular aortic repair (TEVAR). METHODS: This retrospective study included 547 consecutive patients diagnosed with TBAD who underwent TEVAR at our institution between January 2014 and December 2019. Patients were categorized into two groups: the PIS group (patients with post-TEVAR PIS) and the non-PIS group (patients without post-TEVAR PIS). In-hospital and follow-up data were analyzed. RESULTS: The incidence of PIS was 28.9% (158/547 patients). No baseline differences were observed between the PIS (n = 158) and the non-PIS (n = 389) groups. The proportion of emergency surgery in the PIS group was higher than that in the non-PIS group (44.9% vs 26.0%; P < .001), the operation time was longer (median, 65.0; interquartile range [IQR], 56.0-75.0 minutes vs 56.0; IQR, 45.0-66.0 minutes; P < .001), the volume of contrast medium used (median, 65.0; IQR, 56.0-75.0 mL vs 56.0; IQR, 45.0-66.0 mL; P < .001), and the average number of trunk stents (1.85 ± 0.4 vs 1.34 ± 0.5 pieces; P < .001) and branch stents (0.7 ± 0.7 vs 0.2 ± 0.5 pieces; P < .001) used were more in the PIS group than in the non-PIS group. The incidence of supra-aortic branch procedures was higher in the PIS group than in the non-PIS group. There was no significant difference in device-related complications (DRCs) or 30-day mortality between the two groups (2.5% vs 4.4%; P = .442 and 1.3% vs 1.3%; P = .688, respectively). Univariate and multivariable logistic regression analysis showed that emergency surgery, number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL were risk factors for PIS, and the odds ratios of emergency operation, number of trunk stents >1 piece, operation time >58.5 minutes, and contrast medium volume >75 mL were 2.526 (95% confidence interval [CI], 1.530-4.173), 4.651 (95% CI, 2.838-7.624), 3.577 (95% CI, 2.201-5.815), and 7.356 (95% CI, 4.111-13.160), respectively. Follow-up was completed in 98.5% (532/540) of the patients, with a median follow-up of 67 months (IQR, 50-86 months). There was no significant difference in survival between the PIS and non-PIS groups (12.4% vs 10.3%; P = .476) during follow-up. The incidences of DRCs (7.8% vs 11.6%; P = .200) and aortic false lumen thrombosis (75.8% vs 79.2%; P = .399) were comparable between the PIS and non-PIS groups. Univariate logistic regression analysis showed that PIS had no effect on long-term follow-up mortality, DRCs, entry flow, or aortic false lumen thrombosis rate. CONCLUSIONS: PIS is relatively common after TEVAR and emergency surgery; number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL are of high predictive value for the assessment of PIS after TEVAR. However, PIS had little effect on early and late postoperative mortality or DRCs.

A single-center experience of type B aortic intramural hematoma.

OBJECTIVE: The outcomes of the best medical treatment (BMT) and intervention treatment (INT) in a single-center experience were reported in type B intramural hematoma (IMH). METHODS: From February 2015 to February 2021, a total of 195 consecutive patients with type B IMH were enrolled in the study. The primary end point was mortality, and the secondary end points included clinical and imaging outcomes. The clinical outcomes were aortic-related death, retrograde type A aortic dissection, stent graft-induced new entry tear, endoleak, and reintervention. The imaging outcome was evaluated through the latest follow-up computed tomography angiography, which included aortic rupture, aortic dissection, aortic aneurysm, rapid growth of aortic diameter, newly developed or enlarged penetrating aortic ulcer or ulcer-like projection (ULP) and increased aortic wall thickness. Kaplan-Meier curves were used to assess the association between different treatments. RESULTS: Among the enrolled patients, 115 received BMT, and 80 received INT. There was no significant difference in early (1.7% vs 2.5%; P = 1.00) and midterm all-cause death (8.3% vs 5.2%; P = .42) between the BMT and INT groups. However, patients who underwent INT were at risk of procedure-related complications such as stent graft-induced new entry tear and endoleaks. The INT group was associated with a profound decrease in the risk of ULP, including newly developed ULP (4.3% vs 26.9%; P < .05), ULP enlargement (6.4% vs 31.3%; P < .05), and a lower proportion of high-risk ULP (10.9% vs 45.6%; P < .05). Although there was no significant difference in the incidence of IMH regression between the two groups, the maximum diameter of the descending aorta in patients receiving INT was larger compared with those treated with BMT. CONCLUSIONS: Based on our limited experience, patients with type B IMH treated with BMT or INT shared similar midterm clinical outcome. Patients who underwent INT may have a decreased risk of ULPs, but a higher risk of procedure-related events and patients on BMT should be closely monitored for ULP progression.

Acute kidney injury in patients undergoing endovascular or open repair of juxtarenal or pararenal aortic aneurysms.

BACKGROUND: The aim of this cohort study was to report the proportion of patients who develop periprocedural acute kidney injury (AKI) after endovascular repair (ER) and open surgery (OS) in patients with juxta/pararenal abdominal aortic aneurysm and to assess potential risk factors for AKI. The study also aimed to report the short- and long-term outcomes of patients with and without AKI. METHODS: This was a multicenter cohort study of five European academic high-volume centers (>50 OS or 50 ER infrarenal AAA repairs, plus >15 complex AAA repairs per year). All consecutively treated patients were extracted from a prospective vascular surgical registry and the data were scrutinized retrospectively. The primary end point for this study was the development of AKI. AKI was diagnosed when there is a two-fold increase of serum creatinine or decrease of glomerular filtration rate of >50% within 1 week of AAA repair. Secondary end points included long-term mortality and end-stage renal disease (ESRD). RESULTS: AKI occurred in 16.6% of patients in the ER group vs 30.3% in the OS group (P < .001). The 30-day mortality rate was higher among patients with AKI in both ER (15.4% vs 3.1%; P = .006) and OS (13.2% vs 5.3%; P = .001) groups. Age, chronic kidney disease, presence of significant thrombus burden in the pararenal region, >1000 mL blood loss in ER group were associated with development of AKI. Age, diabetes mellitus, chronic kidney disease, presence of significant thrombus burden in the pararenal region, and a proximal clamping time of >30 minutes in the OS group were associated with the development of AKI, whereas renal perfusion during clamping was the protective factor against AKI development. After a median follow-up of 91 months, AKI was associated with higher mortality rates in both the ER group (58.9% vs 29.7%; P < .001) and the OS group (61.5% vs 27.3%; P < .001). After the same follow-up period, AKI was associated with a higher incidence of ESRD in both the ER group (12.8% vs 3.6%; P = .009) and the OS group (9.9% vs 2.9%; P < .001). CONCLUSIONS: The current study identified important pre and postoperative factors associated with AKI after juxta/pararenal abdominal aortic aneurysm repair. Patients with postoperative AKI had significantly higher short- and long term mortality and higher incidence of ESRD than patients without AKI.

Five-year outcomes for bell bottom, iliac branch endoprosthesis, and coil and cover approaches from the GREAT registry.

OBJECTIVE: There are a variety of methods used today to treat common iliac aneurysms with endovascular techniques. Of these approaches, little is known about whether a particular limb strategy influences endoleak, reintervention, or aneurysm regression rates. We present 5-year data comparing endoleak, stent graft migration, fracture, aneurysm sac dynamics, and aortic rupture rates among patients treated with bell bottom limbs (BB), iliac branch endoprosthesis (IBE), and coil and cover (CC) approaches from the Global Registry for Endovascular Aortic Treatment registry. Secondary end points were all-cause mortality, stroke, reintervention, and paraplegia. METHODS: Subjects from the GORE Global Registry for Endovascular Aortic Treatment were enrolled over a 5-year period from October 2017 to August 2022. We included 924 subjects in this study. Statistical data was generated on R software and limb groups were compared using the Pearson's χ2 test and the Kruskal-Wallis rank-sum test. RESULTS: We found no statistical difference in endoleak rates, stent graft migration, fracture, or aortic rupture when stratified by limb strategy. There was no difference between limb approaches with regard to aneurysm sac dynamics among those with abdominal aortic aneurysms and common iliac aneurysms. Similarly, no statistical difference between limb strategies was found in all-cause mortality, stroke, paraplegia, or reintervention rates. Among patients that required an additional graft during reintervention, the highest rates were found within the IBE group 8.6%, compared with BB group 2.2% and CC group 1.3% (P = .006). CONCLUSIONS: Overall, there was no difference among limb strategies in endoleak rates, stent graft migration, aneurysm sac dynamics, aortic rupture rates, or our secondary end points. Increased rates of reintervention requiring an additional graft within the IBE group is noteworthy and must be weighed against the adverse effects of hypogastric sacrifice with the CC approach or potentially less advantageous seal zones in the BB approach. This finding suggests that all limb approaches have equivalent effectiveness in managing the aneurysmal common iliac artery; thus, the choice of limb strategy should be individualized and remain at physician discretion. Future research should include a more robust sample size to reproduce these findings.

Early outcomes of endovascular repairs of the aortic arch using thoracic branch endoprosthesis.

OBJECTIVE: The only commercially available thoracic branched endoprosthesis (TBE) for treatment of the aortic arch was released in 2022. Limited data outside of clinical trial results have been reported. This study describes the demographics, anatomic details, and outcomes for patients treated for zone 0 to 2 using TBEs outside of a clinical trial. METHODS: All patients treated using TBEs for zone 0 to 2 were included. Patients treated as part of the clinical trial for zone 0 to 1 (n = 6) were excluded. Patient demographics, comorbidities, anatomic and operative details, and outcomes were reported. Outcomes and survival were then compared between groups. RESULTS: Of 40 patients, six patients underwent repair of zone 0, three of zone 1, and 31 of zone 2. There were no differences in demographics, comorbidities, or operative details by zone of treatment; however, the frequency of genetic aortopathy differed (zone 0: 0%; zone 1: 67%; and zone 2: 6.4%; P < .01). Seventy-three percent of patients were treated for dissection vs 27% with isolated aneurysms. Of the patients, 2.5% were treated for rupture, 22% were treated for symptomatic aneurysms, and 75% were treated electively. Forty-eight percent of repairs included a proximal cuff, and 83% received distal extension. Technical success was achieved in 100% of patients. Mean fluoroscopy time was 18 minutes, and median fluoroscopy dose was 416 mGy. Sixty percent of patients had prior aortic ascending/arch repair. TBE was planned as part of a complete thoracoabdominal repair in 45% of patients. Thirty-day mortality was 2.5% overall, with a single death in a zone 0 patient that occurred at day 1 due to a myocardial infarction. There were no reinterventions within 30 days. All other outcomes were similar. The 30-day stroke rate was 5.0%. The strokes occurred at day 6 (zone 1) and day 15 (zone 2); however, both were due to occlusion of a prior proximal surgical bypass and unrelated to the TBE side branch or embolization. Specifically, both patients had occlusion of a branch of their prior zone 1 or zone 2 arch replacement. An endoleak occurred in 7.5% of patients at 30-day follow-up (type II: 5.0%; unknown: 2.5%). At a mean follow-up of 6.6 months, 100% of side branches were patent. CONCLUSIONS: Repair of the aortic arch including TBE can be performed electively and urgently with acceptable stroke and death rates. TBE provides a valuable tool for patients requiring complete repair of a thoracoabdominal aneurysm. Continued investigation is underway to assess long-term safety and efficacy outside of the clinical trial.

Surgeon volume and outcomes following thoracic endovascular aortic repair for blunt thoracic aortic injury.

OBJECTIVE: Thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injury (BTAI) at high-volume hospitals has previously been associated with lower perioperative mortality, but the impact of annual surgeon volume on outcomes following TEVAR for BTAI remains unknown. METHODS: We analyzed Vascular Quality Initiative (VQI) data from patients with BTAI that underwent TEVAR between 2013 and 2023. Annual surgeon volumes were computed as the number of TEVARs (for any pathology) performed over a 1-year period preceding each procedure and were further categorized into quintiles. Surgeons in the first volume quintile were categorized as low volume (LV), the highest quintile as high volume (HV), and the middle three quintiles as medium volume (MV). TEVAR procedures performed by surgeons with less than 1-year enrollment in the VQI were excluded. Using multilevel logistic regression models, we evaluated associations between surgeon volume and perioperative outcomes, accounting for annual center volumes and adjusting for potential confounders, including aortic injury grade and severity of coexisting injuries. Multilevel models accounted for the nested clustering of patients and surgeons within the same center. Sensitivity analysis excluding patients with grade IV BTAI was performed. RESULTS: We studied 1321 patients who underwent TEVAR for BTAI (28% by LV surgeons [0-1 procedures per year], 52% by MV surgeons [2-8 procedures per year], 20% by HV surgeons [≥9 procedures per year]). With higher surgeon volume, TEVAR was delayed more (in <4 hours: LV: 68%, MV: 54%, HV: 46%; P < .001; elective (>24 hours): LV: 5.1%; MV: 8.9%: HV: 14%), heparin administered more (LV: 80%, MV: 81%, HV: 87%; P = .007), perioperative mortality appears lower (LV: 11%, MV: 7.3%, HV: 6.5%; P = .095), and ischemic/hemorrhagic stroke was lower (LV: 6.5%, MV: 3.6%, HV: 1.5%; P = .006). After adjustment, compared with LV surgeons, higher volume surgeons had lower odds of perioperative mortality (MV: 0.49; 95% confidence interval [CI], 0.25-0.97; P = .039; HV: 0.45; 95% CI, 0.16-1.22; P = .12; MV/HV: 0.50; 95% CI, 0.26-0.96; P = .038) and ischemic/hemorrhagic stroke (MV: 0.38; 95% CI, 0.18-0.81; P = .011; HV: 0.16; 95% CI, 0.04-0.61; P = .008). Sensitivity analysis found lower adjusted odds for perioperative mortality (although not significant) and ischemic/hemorrhagic stroke for higher volume surgeons. CONCLUSIONS: In patients undergoing TEVAR for BTAI, higher surgeon volume is independently associated with lower perioperative mortality and postoperative stroke, regardless of hospital volume. Future studies could elucidate if TEVAR for non-ruptured BTAI might be delayed and allow stabilization, heparinization, and involvement of a higher TEVAR volume surgeon.

The outcomes of aortic arch repair between open surgical repair and debranching endovascular hybrid surgical repair: A systematic review and meta-analysis.

BACKGROUND: At present, open surgical aortic arch repair (OAR) and debranching hybrid surgical aortic arch repair (HAR) serve as significant therapeutic approaches for aortic arch aneurysm or dissection. It remains unclear which technique is preferable. Our study aimed to compare the short-term and long-term outcomes of these two procedures. METHODS: To identify comparison studies of debranching HAR and OAR, a systematic search of the PubMed, Embase, Web of Science, and Cochrane Library databases was performed from January 2002 to April 2022. This study was registered on PROSPERO (CRD42020218080). RESULTS: Sixteen publications (1316 patients), including six propensity score-matching (PSM) analysis papers, were included in this study. Compared with the HAR group, the patients who underwent OAR were younger (OAR vs HAR: 67.53 ± 12.81 vs 71.29 ± 11.0; P < .00001), had less coronary artery disease (OAR vs HAR: 22.45% vs 32.6%; P = .007), less chronic obstructive pulmonary disease (OAR vs HAR: 16.16% vs 23.92%; P = .001), lower rates of previous stroke (OAR vs HAR: 12.46% vs 18.02%; P = .05), and a lower EuroSCORE (European System for Cardiac Operative Risk Evaluation) score (OAR vs HAR: 6.27 ± 1.04 vs 6.9 ± 3.76; P < .00001). HAR was associated with less postoperative blood transfusion (OAR vs HAR: 12.23% vs 7.91%; P = .04), shorter length of intensive care unit stays (OAR vs HAR: 5.92 ± 7.58 days vs 4.02 ± 6.60 days; P < .00001) and hospital stays (OAR vs HAR: 21.59 ± 17.54 days vs 16.49 ± 18.45 days; P < .0001), lower incidence of reoperation for bleeding complications (OAR vs HAR: 8.07% vs 3.96%; P = .01), fewer postoperative pulmonary complication (OAR vs HAR: 14.75% vs 5.02%; P < .0001), and acute renal failure (OAR vs HAR: 7.54% vs 5.17%; P = .03). In the PSM subgroup, the rates of spinal cord ischemic (OAR vs HAR: 5.75% vs 11.49%; P = .02), stroke (OAR vs HAR: 5.1% vs 17.35%; P = .01), and permanent paraplegia (OAR vs HAR: 2.79% vs 6.08%; P = .006) were lower in the OAR group than that in the HAR group. Although there was no statistically significant difference in 1-year survival rates (HAR vs OAR: hazard ratio [HR]: 1.54; P = .10), the 3-year and 5-year survivals were significantly higher in the OAR group than that in the HAR group (HAR vs OAR: HR: 1.69; P = .01; HAR vs OAR: HR: 1.68; P = .01). In the PSM subgroup, the OAR group was also significantly superior to the HAR group in terms of 3-year and 5-year survivals (HAR vs OAR: HR: 1.73; P = .04; HAR vs OAR: HR: 1.67; P = .04). The reintervention rate in the HAR group was significantly higher than that in the OAR group (OAR vs HAR: 8.24% vs 16.01%; P = .01). The most common reintervention was postoperative bleeding (8.07%) in the OAR group and endoleak (9.67%) in the HAR group. CONCLUSIONS: Our meta-analysis revealed that debranching HAR was associated with fewer perioperative complications than the OAR group, except for postoperative permanent paraplegia, reintervention, and stroke events. The OAR group demonstrated better 3-year and 5-year survivals than the debranching HAR group. However, patients in the OAR group had fewer comorbid factors and were younger than those in the HAR group. High-quality studies and well-powered randomized trials are needed to further evaluate this evolving field.

Prognostic factors after open and endovascular repair for infected native aneurysms of the abdominal aorta and common iliac artery.

OBJECTIVE: Infected native aneurysms (INAs) of the abdominal aorta and iliac arteries are uncommon, but potentially fatal. Endovascular aneurysm repair (EVAR) has recently been introduced as a durable treatment option, with outcomes comparable to those yielded by conventional open repair. However, owing to the rarity of the disease, the strengths and limitations of each treatment remain uncertain. The present study aimed to separately assess post-open repair and post-EVAR outcomes and to clarify factors affecting the short-term and late prognosis after each treatment. METHODS: Using a nationwide clinical registry, we investigated 600 patients treated with open repair and 226 patients treated with EVAR for INAs of the abdominal aorta and/or common iliac artery. The relationships between preoperative or operative factors and postoperative outcomes, including 90-day and 3-year mortality and persistent or recurrent aneurysm-related infection, were examined. RESULTS: Prosthetic grafts were used in >90% of patients treated with open repair, and in situ and extra-anatomic arterial reconstruction was performed in 539 and 57 patients, respectively. Preoperative anemia and imaging findings suggestive of aneurysm-enteric fistula were independently associated with poor outcomes in terms of both 3-year mortality (hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.01-2.62; P = .046, and HR, 2.24; 95% CI, 1.12-4.46; P = .022, respectively) and persistent or recurrent infection (odds ratio [OR], 2.16; 95% CI, 1.04-4.49; P = .039, and OR, 4.96; 95% CI, 1.81-13.55; P = .002, respectively) after open repair, whereas omental wrapping or packing and antibiotic impregnation of the prosthetic graft for in situ reconstruction contributed to improved 3-year survival (HR, 0.60; 95% CI, 0.39-0.92; P = .019, and HR, 0.53; 95% CI, 0.32-0.88; P = .014, respectively). Among patients treated with EVAR, abscess formation adjacent to the aneurysm was significantly associated with the occurrence of persistent or recurrent infection (OR, 2.24; 95% CI, 1.06-4.72; P = .034), whereas an elevated preoperative white blood cell count was predictive of 3-year mortality (HR, 1.77; 95% CI, 1.00-3.13; P = .048). CONCLUSIONS: Profiles of prognostic factors differed between open repair and EVAR in the treatment of INAs of the abdominal aorta and common iliac artery. Open repair may be more suitable than EVAR for patients with concurrent abscess formation.

Stent-Graft Placement for Hepatic Arterial Hemorrhage after Pancreaticobiliary Surgery: Long-Term Clinical Outcomes.

PURPOSE: To evaluate the safety and long-term clinical outcomes of stent-graft placement to treat hepatic arterial hemorrhage after pancreaticobiliary surgery. MATERIALS AND METHODS: Outcomes were retrospectively evaluated in 61 patients (50 men and 11 women; mean age, 63 years) who underwent stent-graft placement for delayed arterial hemorrhage (after 24 hours) after pancreaticobiliary surgery from 2006 to 2023. Bleeding sites included the gastroduodenal artery stump (n = 54), common or proper hepatic artery (n = 5), and right hepatic artery (n = 2). The stent-grafts used were Viabahn (n = 27), Comvi (n = 11), Jostent (n = 3), Covera (n = 11), and Lifestream (n = 7). Technical and clinical success and adverse events (AE) were evaluated. After stent-graft placement, overall survival (OS), hemorrhage-free survival (HFS), and stent patency were evaluated. RESULTS: The technical and clinical success rates of stent-graft placement were 97% and 93%, respectively. The severe AE rate was 12% and was significantly higher in patients who underwent pylorus-sacrificing rather than pylorus-preserving surgery (P = .001). None of the severe AEs were associated with patient mortality. Median OS after stent-graft placement was 854 days, and median HFS was 822 days. The 1-, 3-, 5-, and 10-year stent patency rates were 87%, 84%, 79%, and 72%, respectively. CONCLUSIONS: Stent-graft placement was safe and provided long-term control of hepatic arterial hemorrhage after pancreaticobiliary surgery.

The Complementary Roles of Open and Endovascular Repair of Extent I - III Thoraco-abdominal Aortic Aneurysms in a United Kingdom Aortic Centre.

OBJECTIVE: A multidisciplinary approach offering both open surgical repair (OSR) and complex endovascular aortic repair (cEVAR) is essential if patients with thoraco-abdominal aortic aneurysms (TAAAs) are to receive optimal care. This study reports early and midterm outcomes of elective and non-elective OSR and cEVAR for extent I - III TAAA in a UK aortic centre. METHODS: Retrospective study of consecutive patients treated between January 2009 and December 2021. Primary endpoint was 30 day/in hospital mortality. Secondary endpoint was Kaplan-Meier estimates of midterm survival. Data are presented as median (interquartile range [IQR]). RESULTS: In total, 296 patients (176 men; median age 71 years [IQR 65, 76]; median aneurysm diameter 66 mm [IQR 61, 75]) underwent repair (222 elective, 74 non-elective). OSR patients (n = 66) were significantly younger with a higher incidence of heritable disease and chronic dissection, while cEVAR patients (n = 230) had a significantly higher prevalence of coronary, pulmonary, and renal disease. Overall, in hospital mortality after elective and non-elective repair was 3.2% (n = 7) and 23.0% (n = 17), respectively, with no significant difference between treatment modalities (elective OSR 6.5% vs. cEVAR 2.3%, p = .14; non-elective OSR 25.0% vs. cEVAR 20.3%, p = .80). Major non-fatal complications occurred in 15.3% (33/215) after elective repair (OSR 39.5%, 17/43, vs. cEVAR 9.3%, 16/172; p < .001) and 14% (8/57) after non-elective repair (OSR 26.7%, 4/15, vs. cEVAR 9.5%, 4/42; p = .19). Median follow up was 52 months (IQR 23, 78). Estimated survival ± standard error at 1, 3, and 5 years for the entire cohort was 89.6 ± 2.0%, 76.6 ± 2.9%, and 69.0% ± 3.2% after elective repair, and 67.6 ± 5.4%, 52.1 ± 6.0%, and 41.0 ± 6.2% after non-elective repair. There was no difference in 5 year survival comparing modalities after elective repair for patients younger than 70 years and those with post-dissection aneurysms. CONCLUSION: A multidisciplinary approach offering OSR and cEVAR can deliver comprehensive care for extent I - III TAAA with low early mortality and good midterm survival. Further studies are required to determine the optimal complementary roles of each treatment modality.

Hospital Volume of Elective Abdominal Aortic Aneurysm Repair as a Predictor of Mortality After Ruptured Abdominal Aortic Aneurysm Repair.

OBJECTIVE: Registry data suggest that centralising abdominal aortic aneurysm (AAA) surgery decreases the mortality rate after AAA repair. However, the impact of higher elective volumes on ruptured AAA (rAAA) repair associated mortality rates remains uncertain. This study aimed to examine associations between intact AAA (iAAA) repair volume and post-operative rAAA death. METHODS: Using data from official national registries between 2015 - 2019, all iAAA and rAAA repairs were separately analysed across 10 public hospitals. The following were assessed: 30 day and 12 month mortality rate following open surgical repair (OSR) and endovascular aneurysm repair (EVAR). Associations between the 5 year hospital iAAA repair volumes (organised into tertiles) and rAAA associated mortality rate were analysed, regardless of treatment modality. Receiver operating characteristic (ROC) curves were generated to identify iAAA volume thresholds for decreasing the rAAA mortality rate. Subanalysis by treatment type was conducted. Threshold analysis was repeated with the Markov chain Monte Carlo (MCMC) procedure to confirm the findings. RESULTS: A total of 1 599 iAAAs (80.2% EVAR, 19.8% OSR) and 196 rAAAs (66.3% EVAR, 33.7% OSR) repairs were analysed. The median and interquartile range of the volume/hospital/year for all iAAA repairs were 39.2 (31.2, 47.4). The top volume iAAA tertile exhibited lower rAAA associated 30 day (odds ratio [OR] 0.374; p = .007) and 12 month (OR 0.264; p < .001) mortality rates. The ROC analysis revealed a threshold of 40 iAAA repairs/hospital/year (EVAR + OSR) for a reduced rAAA mortality rate. Middle volume hospitals for open iAAA repair had reduced 30 day (OR 0.267; p = .033) and 12 month (OR 0.223; p = .020) mortality rates, with a threshold of five OSR procedures/year. The MCMC procedure found similar thresholds. No significant association was found between elective EVAR volumes and ruptured EVAR mortality. CONCLUSION: Higher iAAA repair volumes correlated with a lower rAAA mortality rate, particularly for OSR. The recommended iAAA repair threshold is 40 procedures/year and five procedures/year for OSR. These findings support high elective volumes for improving the rAAA mortality rate, especially for OSR.

Long Term Outcomes of the Gore Excluder Low Permeability Endoprosthesis for the Treatment of Infrarenal Aortic Aneurysms.

OBJECTIVE: This study evaluated the long term outcomes of endovascular aneurysm repair using the Gore Excluder Low Permeability (LP) endoprosthesis across high volume Dutch hospitals. METHODS: A retrospective analysis was conducted of patients treated with the Excluder LP for infrarenal abdominal aortic aneurysm (AAA) in four hospitals between 2004 and 2017. Primary outcomes were overall survival, freedom from re-interventions (overall, inside and outside instructions for use, IFU), and AAA sac dynamics: growth (> 5 mm), stabilisation, and regression (< 5 mm). Secondary outcomes were technical success (device deployment), procedural parameters, and re-interventions. Follow up visits were extracted from patient files, with imaging assessed for complications and AAA diameter. RESULTS: Five hundred and fourteen patients were enrolled, with a median (IQR) follow up of 5.0 (2.9, 6.9) years. Survival rates were 94.0% at one year, 73.0% at five years, and 37.0% at 10 years, with freedom from re-interventions of 89.0%, 79.0%, and 71.0%, respectively. 37.9% were treated outside IFU, leading to significantly more re-interventions over 10 years compared with those treated inside IFU (36.0% vs. 25.0%, respectively; p = .044). The aneurysm sac regressed by 53.5% at one year, 65.8% at five years, and 77.8% at 10 years, and grew by 9.8%, 14.3%, and 22.2%, respectively. Patients with one year sac growth had significantly worse survival (p = .047). Seven patients (1.4%) had a ruptured aneurysm during follow up. Over 15 years, type 1a endoleak occurred in 5.3%, type 1b in 3.1%, type 3 in 1.9%, type 4 in 0.2%, and type 2 in 35.6% of patients. CONCLUSION: This multicentre study of real world endovascular aneurysm repair data using the Gore Excluder LP endoprosthesis demonstrated robust long term survival and re-intervention rates, despite 37.9% of patients being treated outside IFU, with type 4 endoleak being rare. Treatment outside IFU significantly increased re-intervention rates and one year sac growth was associated with statistically significantly worse survival.