Treatment Outcome Trends for Non-Ruptured Abdominal Aortic Aneurysms: A Nationwide Prospective Cohort Study

Textbook outcomes as a novel patient-centric metric to inform carotid revascularization

OBJECTIVE

The recent National Coverage Determination surrounding carotid stenting and shared decision-making has ushered in an era of patient-centric carotid care. However, historical carotid intervention endpoints have lacked patient-centered nuances to inform clinical decisions. Accordingly, we aimed to create a comprehensive novel, patient-centric textbook outcome (TO) to inform treatment paradigms.

METHODS

We developed a novel composite TO for patients who underwent carotid revascularization reflecting a combination of patient-centric outcomes derived from previous patient interviews and the published literature. We defined a TO to include freedom from postprocedural neurologic events, myocardial infarction, cranial nerve injury, return to the operating room, reperfusion syndrome, or access site complications. The endpoint also included discharge on postprocedural day 1, home discharge, and 30-day survival. We measured the risk of a TO vs non-TO among asymptomatic patients undergoing carotid endarterectomy (CEA), transcarotid artery revascularization (TCAR), or transfemoral carotid artery stenting (TF-CAS) in the Vascular Quality Initiative (VQI) from 2016 to 2023.

RESULTS

We studied 72,778 patients who underwent carotid revascularization, 70.3% CEA, 21.0% TCAR, and 8.7% TF-CAS. The mean age across all patients was 71.6 ± 8.4 years, 39.9% were female, and 91.7% were White. A TO was achieved in 76.9% of patients, and was 76.7% after CEA, 76.5% after TCAR, and 79.1% after TF-CAS (P < .001). Postprocedural length of stay was 2 days or more in 21.0% of patients, and was 21.1% after CEA, 21.6% after TCAR, and 18.4% after TF-CAS (P < .001). Postprocedural neurologic events occurred in 1.0% of patients after CEA, 1.3% after TCAR, and 1.4% after TF-CAS (P = .037). A sensitivity analysis of the TO that did not include postprocedural length of stay demonstrated a non-TO in 5.9% of patients after CEA, 5.5% after TCAR, and 6.3% after TF-CAS (P = .070). Patients who did not achieve a TO had inferior 5-year survival compared with patients who did have a TO across all three cohorts (log-rank P < .001).

CONCLUSIONS

This novel patient-centric endpoint demonstrated that a substantial percentage of patients fail to achieve a TO in current practice, and that failure to achieve a TO was associated with inferior 5-year survival. These findings are particularly important in light of the recent Medicare mandate for a shared decision-making approach to carotid care delivery and may help to best align patient preferences with procedure type.

Does Functional Status Predict Worse 30-D Outcomes in Endovascular Repair of Abdominal Aortic Aneurysms? A Propensity-Score Matched Study From ACS-NSQIP Targeted Database From 2012 to 2022

INTRODUCTION

In patients undergoing endovascular aneurysm repair (EVAR), existing studies have identified an association between dependent functional status (DFS) and poorer outcomes after EVAR. However, noted limitations, especially the lack of differentiation between ruptured and nonruptured abdominal aortic aneurysm (AAA), potentially affect the extrapolation of these findings to specific patient groups. Thus, this study aimed to evaluate the association between functional status and 30-d outcomes after EVAR in ruptured and nonruptured AAA patients separately.

METHODS

Patients who underwent infrarenal EVAR were identified in the American College of Surgeons National Surgical Quality Improvement Program targeted database from 2012-2022. Patients with DFS and those with independent functional status (IFS) were stratified into the two study cohorts. In nonruptured AAA, a 1:1 propensity-score matching was used to address demographics, baseline characteristics, aneurysm diameter, distal extent of the aneurysm, anesthesia, and concomitant procedures between patients with DFS and IFS. The sample size for ruptured patients with AAA was too small for meaningful statistical analysis so only qualitative description was provided. Thirty-d postoperative mortality and morbidities of EVAR were assessed.

RESULTS

For nonruptured cases, there were 380 (2.55%) DFS and 14,545 (97.45%) patients with IFS, where 453 patients with IFS were matched to the DFS cohort. For ruptured AAA, there were 17 (6.39%) DFS and 249 (93.61%) IFS. After matching, nonruptured DFS and patients with IFS had similar 30-d mortality rates (2.37% vs 2.11%, P = 1.00). However, patients with DFS had a higher risk of bleeding requiring transfusion (18.42% vs 11.84%, P = 0.01) and longer length of stay (median 3.00 [Q1 1.00, Q3 6.00] vs median 2.00 [Q1 1.00, Q3 4.00] d, P < 0.01). All other outcomes, including major adverse cardiovascular events, cardiac complications, stroke, pulmonary complications, renal complications, sepsis, venous thromboembolism, wound complications, lower extremity ischemia, ischemic colitis, postoperative ruptured aneurysm, unplanned reoperation, 30-d readmission, were not different between patients with DFS and IFS. Qualitatively, ruptured patients with DFS had higher crude rates of 30-d mortality and morbidities compared to patients with IFS.

CONCLUSIONS

Contrary to previous literature, patients with DFS with nonruptured AAA undergoing EVAR were found to have largely comparable outcomes to patients with IFS, although extra attention should be paid to postoperative bleeding.

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.

Identification of abdominal aortic aneurysm subtypes based on mechanosensitive genes

BACKGROUND

Rupture of abdominal aortic aneurysm (rAAA) is a fatal event in the elderly. Elevated blood pressure and weakening of vessel wall strength are major risk factors for this devastating event. This present study examined whether the expression profile of mechanosensitive genes correlates with the phenotype and outcome, thus, serving as a biomarker for AAA development.

METHODS

In this study, we identified mechanosensitive genes involved in AAA development using general bioinformatics methods and machine learning with six human datasets publicly available from the GEO database. Differentially expressed mechanosensitive genes (DEMGs) in AAAs were identified by differential expression analysis. Molecular biological functions of genes were explored using functional clustering, Protein-protein interaction (PPI), and weighted gene co-expression network analysis (WGCNA). According to the datasets (GSE98278, GSE205071 and GSE165470), the changes of diameter and aortic wall strength of AAA induced by DEMGs were verified by consensus clustering analysis, machine learning models, and statistical analysis. In addition, a model for identifying AAA subtypes was built using machine learning methods.

RESULTS

38 DEMGs clustered in pathways regulating 'Smooth muscle cell biology' and 'Cell or Tissue connectivity'. By analyzing the GSE205071 and GSE165470 datasets, DEMGs were found to respond to differences in aneurysm diameter and vessel wall strength. Thus, in the merged datasets, we formally created subgroups of AAAs and found differences in immune characteristics between the subgroups. Finally, a model that accurately predicts the AAA subtype that is more likely to rupture was successfully developed.

CONCLUSION

We identified 38 DEMGs that may be involved in AAA. This gene cluster is involved in regulating the maximum vessel diameter, degree of immunoinflammatory infiltration, and strength of the local vessel wall in AAA. The prognostic model we developed can accurately identify the AAA subtypes that tend to rupture.

Predictors of 30-Day Postoperative Outcome after Elective Endovascular Abdominal Aortic Aneurysm Repair: A Tertiary Referral Center Experience

BACKGROUND

We evaluated the 30-day postoperative outcome after elective endovascular aneurysm repair (EVAR) and the possible predictors for the 30-day postoperative outcome.

MATERIALS

Demographics, medical history, laboratory values, intensive care unit (ICU) admission and 30-day complications classified as major (major adverse cardiovascular events (MACEs), acute kidney injury (AKI) and death of any cause) and minor (postimplantation syndrome (PIS), postoperative delirium (POD), urinary tract infection (UTI) and technical graft failure) were documented (March 2016 to February 2019).

RESULTS

We included 322 patients. The majority were managed under general anesthesia (83%) with femoral cutdown (98.1%). Overall, 121 (37.5%) complications, mostly minor (n = 103, 31.9%), were recorded. In total, 11 patients (3.4%) developed MACEs, 5 (1.6%) experienced AKI and 2 (0.6%) died in the ICU. Moreover, 77 patients (23.9%) suffered from PIS, 11 from POD, 11 from UTI and 4 from technical graft failure. The multivariate logistic regression analysis revealed that aneurysm diameter (p = 0.01) and past smoking (p = 0.003) were predictors for complications. PAD was an independent predictor of MACEs (p = 0.003), preoperative neutrophil to lymphocyte ratio (NLR) of AKI (p = 0.003) and past smoking of PIS (p = 0.008), respectively.

CONCLUSIONS

Our study showed that the 30-day morbidity after EVAR exceeded 35%. However, the majority of complications were minor, and the associated mortality was low. Aneurysm diameter and past smoking were independent predictors for postoperative outcome.

An Epidemiologic Study of the Incidence and Mortality of Abdominal Aortic Aneurysms in Koreans Aged ≥50 Years from 2009 to 2018 Based on a National Database

Large-scale population studies of the incidence of and mortality from abdominal aortic aneurysm (AAA) are needed to develop healthcare policies and priorities. The aim of this study was to estimate the incidence of AAA and the all-cause mortality from it among Koreans aged ≥50 years from 2009 to 2018 using data from the Korean National Health Insurance System Database. The crude and standardized incidence and all-cause mortality of the disease among patients with unruptured AAA were calculated. A total of 73,933 AAA patients were identified. The overall incidence of AAA in adults ≥50 years during the study period was 37.5 per 100,000 population (49.7 per 100,000 in men and 26.8 per 100,000 in women), with an increase from 32.33 per 100,000 persons in 2009 to 46.85 per 100,000 in 2018. The crude all-cause mortality rate of patients with untreated AAA was 21.26/100 person-years in 2009 and 8.87/100 person-years in 2018, with decreasing trends observed both in men and women. This nationwide study showed that the incidence of AAA in Koreans aged ≥50 years in 2018 was 63.40 per 100,000 in men and 32.07 per 100,000 in women. The overall rates were 0.06% and 0.03%, respectively, with an increasing trend. Mortality has decreased in both treated and untreated patients. The observed increase in incidence suggests a rising burden of AAA in the Korean population, particularly among men. The decreasing mortality rates may indicate improvements in the management and treatment of AAA over the study period.