Epidemiology of thoracoabdominal aortic aneurysms

Impact of preoperative risk factors on 5-year survival after fenestrated/branched endovascular aortic repair

OBJECTIVE

To investigate which preoperative factors most impact the 5-year survival of patients undergoing fenestrated/branched endovascular aortic repair (F/BEVAR) and to identify modifiable elements that, if time allows, should be actively managed and adequately controlled preoperatively.

METHODS

Patients treated for aortic aneurysms with complex anatomy using either patient-specific company-manufactured or off-the-shelf F/BEVAR devices were included. The exposure of interest was aneurysm type (group I: type I-III thoracoabdominal aneurysms vs group II: type IV thoracoabdominal aneurysms vs group III: juxtarenal or suprarenal aneurysms), and the primary outcome was 5-year risk of all-cause mortality. Generalized linear models were used to estimate each group's crude 5-year risk of death and the 5-year risk of death across groups. Each preoperative factor was added to the model individually, and a change in estimate was calculated between the new risks and the crude risk. Preoperative factors with a change of estimate of ≥10% were used to create an inverse probability of treatment weights for multivariable analysis.

RESULTS

A total of 408 F/BEVAR patients were included, of whom 71.6% were male (mean age: 72.0 ± 7.9 years). Eleven of the 22 preoperative factors analyzed had a change in estimate ≥10%. The greatest changes in estimates were observed for history of congestive heart failure (CHF), arrhythmia, overweight, obesity, and chronic obstructive pulmonary disease. Almost 60% of patients with CHF in group I died within 5 years. Current smoking or overweight at the time of F/BEVAR increases the 5-year risk of death more significantly than having a history of myocardial infarction. After adjustment, patients in group I had a significantly higher risk of 5-year all-cause mortality than those in group III (log-rank, P value = .0082).

CONCLUSIONS

The present findings suggest that cardiac arrhythmias, CHF, overweight, obesity, chronic obstructive pulmonary disease, and aneurysm diameter above 7 cm are the most relevant preoperative factors that impact the 5-year survival after F/BEVAR. More specifically, CHF and arrhythmias should be used to alter patient selection and identify those individuals more likely to benefit from repair. Moreover, modifiable risk factors such as weight loss and smoking cessation during the surveillance period before the F/BEVAR procedure might improve survival in this population. Considering that, preoperatively, many patients are periodically evaluated by a vascular surgery team until the aneurysm diameter meets criteria for repair, a multidisciplinary approach that could address these modifiable risk factors might be an impactful strategy.

Difference in risk factor profile for abdominal aortic aneurysm and thoracic aortic aneurysm

OBJECTIVE

Previous studies suggest partly different risk factor profiles of thoracic aortic aneurysms (TAAs) and abdominal aortic aneurysms (AAAs), but prospective data are scarce. The purpose of this prospective population-based case-control study was to investigate differences in risk factor profile between TAAs and AAAs.

METHODS

Participants in two prospective population-based studies, the Västerbotten Intervention Project (VIP) and the Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA) study, between 1986 and 2010, underwent cardiovascular risk assessments, including blood samples, oral glucose tolerance test, blood pressure readings, and a self-reported health questionnaire. All individuals who were later diagnosed with TAAs or AAAs were identified. Age, sex, and time-matched controls were selected from the same cohorts, aiming at four controls/case. Adjusted odds ratios (aORs) for potential risk factors for later diagnosis of TAAs and AAAs, respectively, were estimated by multivariate conditional logistic regression analyses.

RESULTS

From a total of 96,196 individuals with prospectively collected data in the VIP/MONICA cohort, a total of 236 individuals with AAAs (181 men and 55 women) and 935 matched controls, and 168 individuals with TAAs (115 men and 53 women) and 662 controls were included. The average age at baseline examination was 57.0 ± 5.7 years for AAA cases and controls, and 52.1 ± 8.8 years for TAA cases and controls. Mean time between baseline examination and diagnosis of AAAs/TAAs was 12.1 and 11.7 years, respectively. There was a clear difference in risk factor profile between AAAs and TAAs. Smoking, hypertension, and coronary artery disease were significantly associated with later diagnosis of AAAs, with highest aORs for a history of smoking (aOR, 10.3; 95% confidence interval [CI], 6.3-16.8). For TAAs, hypertension was the only positive risk factor (aOR, 1.7; 95% CI, 1.1-2.7), whereas smoking was not associated. Diabetes was not associated with either AAAs or TAAs; neither was self-reported physical activity.

CONCLUSIONS

In this prospective, population-based, case-control study, risk factor profile differed between AAAs and TAAs. This suggests a partially different etiology for TAAs and AAAs.

Distribution and Maturity of Medial Collagen Fibers in Thoracoabdominal Post-Dissection Aortic Aneurysms: A Comparative Study of Marfan and Non-Marfan Patients

Thoracoabdominal aortic aneurysms (TAAAs) are rare but serious conditions characterized by dilation of the aorta characterized by remodeling of the vessel wall, with changes in the elastin and collagen content. Individuals with Marfan syndrome have a genetic predisposition for elastic fiber fragmentation and elastin degradation and are prone to early aneurysm formation and progression. Our objective was to analyze the medial collagen characteristics through histological, polarized light microscopy, and electron microscopy methods across the thoracic and abdominal aorta in twenty-five patients undergoing open surgical repair, including nine with Marfan syndrome. While age at surgery differed significantly between the groups, maximum aortic diameter and aneurysm extent did not. Collagen content increased from thoracic to infrarenal segments in both cohorts, with non-Marfan patients exhibiting higher collagen percentages, notably in the infrarenal aorta (729.3 nm vs. 1068.3 nm, p = 0.02). Both groups predominantly displayed mature collagen fibers, with the suprarenal segment containing the highest proportion of less mature fibers. Electron microscopy revealed comparable collagen fibril diameters across segments irrespective of Marfan status. Our findings underscore non-uniform histological patterns in TAAAs and suggest that ECM remodeling involves mature collagen deposition, albeit with lower collagen content observed in the infrarenal aorta of Marfan patients.

Impact of aetiology on short- and long-term outcomes in open descending and thoracoabdominal aneurysm repair

OBJECTIVES

We analysed the impact of chronic type B aortic dissection (cTBAD) and degenerative aneurysm (DA) on the short- and long-term outcomes of patients undergoing open descending thoracic aortic aneurysm and thoracoabdominal aortic aneurysm repair.

METHODS

We performed a retrospective analysis of a prospectively maintained aortic database. From 1999 to 2023, 245 patients underwent open descending thoracic aortic aneurysm or thoracoabdominal aortic aneurysm repair. We compared preoperative comorbidities, postoperative complications and operative and long-term mortality for patients with cTBAD (120 patients, 49%) and DA (125 patients, 51%).

RESULTS

Patients with cTBAD were significantly younger, more likely to be male and less likely to have comorbidities including diabetes, chronic obstructive pulmonary disease and coronary artery disease. There were no statistically significant differences in the incidence of operative mortality between cTBAD (7.5%) and DA patients (11.2%) (P = 0.44). Survival at 1, 5, 10 and 15 years for cTBAD versus DA patients was 90% versus 76%, 79% versus 59%, 59% versus 42% and 50% versus 29%, respectively (P < 0.01); however, this lost statistical significance in the Cox regression (P = 0.86). Following multivariable analysis, older age, female gender, coronary artery disease, urgent or emergent procedure and descending thoracic aortic aneurysm were independent predictors of long-term outcomes.

CONCLUSIONS

There were no statistically significant differences in the incidence of postoperative complications, operative deaths and long-term survival between cTBAD and DA patients.

IRB NUMBER

(#20D.802), Obtained: 1/31/23.

Health Related Quality of Life Following Intervention for Thoracoabdominal Aortic Aneurysm: A Systematic Review and Narrative Synthesis

BACKGROUND

Thoracoabdominal aortic aneurysms (TAAA) pose significant risks of morbidity and mortality. Considering the evolving techniques for TAAA intervention and the growing interest in quality of life (QoL) outcomes for decision-making, we aimed to evaluate the impact of patient and perioperative characteristics on short-term, medium-term, and long-term postoperative QoL in TAAA repair patients.

METHODS

A systematic search was conducted in CINAHL, APA PsycINFO, EMBASE, Medline and Cochrane to identify primary research studies evaluating QoL post TAAA surgery, published in English or Swedish between January 01, 2012 and September 26, 2022. A narrative synthesis was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The quality of evidence was assessed using the Critical Appraisal Skills Program and Joanna Briggs Institute checklists.

RESULTS

Eight studies of low or moderate quality with 455 patients were included. Preoperative QoL in TAAA patients was lower compared to the general population. While there is an initial short-term improvement in postoperative QoL, patients fail to reach baseline levels even after 7 years, with physical activity and functioning domains being particularly affected. Experiencing postoperative complications, including paraplegia and cardiovascular events, negatively impacts postoperative QoL. Patients with uncomplicated postoperative status had improved QoL. Prolonged hospital stay negatively affects physical functioning.

CONCLUSIONS

Individuals with TAAA are likely to have lower baseline QoL compared to the general population. Following TAAA repair, postoperative QoL may remain lower than baseline levels, persisting over the long-term. Comorbidities, postoperative complications, and hospitalization duration appear to exert adverse effects on postoperative QoL.

Changes in treatment patterns of thoracoabdominal aortic aneurysms in the United States

Background

The introduction of endovascular repair provides an alternative to traditional open repair of thoracoabdominal aortic aneurysms (TAAA). Its utility is not well defined, however. Using a national database, we studied the treatment patterns and outcomes of TAAA to gain insight into its contemporary surgical practice in the United States.

Methods

Records of TAAA patients who received endovascular and open repair were retrieved from the 2002 to 2018 National Inpatient Sample database. Each cohort was stratified into 4 age groups: ≤50, 51 to 60, 61 to 70, and >70 years. Patient characteristics and in-hospital outcomes were compared between the 2 repair modalities. Temporal trends were investigated.

Results

Endovascular repair use increased steadily, whereas open repair volume remained stable until 2012, before declining by 50% by 2018. This appears to be associated with a declining number of open repairs in patients age >60 years. Patients who underwent endovascular repair were older and had a higher Charlson Comorbidity Index (mean, 2.8 ± 1.7 vs 2.5 ± 1.5; P < .001) but lower in-hospital mortality (mean, 8.9% vs 17.1%; P < .001), shorter length of stay (mean, 10.1 ± 12.2 days vs 17.1 ± 17.4 days; P < .001), and fewer postoperative complications. A difference in mortality between open and endovascular repair was observed for patients age >60 years but not for patients age ≤60 years.

Conclusions

There has been a shift in the treatment of TAAA in the United States from open repair-dominant to endovascular repair-dominant. It has increased surgical access for older and more comorbid patients and has led to a decline in the use of open repair while lowering in-hospital mortality.

Vascular Biology of arterial aneurysms

OBJECTIVE

This review aims to analyze biomolecular and cellular events responsible for arterial aneurysm formation with particular attention to vascular remodeling that determines the initiation and the progression of arterial aneurysm, till rupture.

METHODS

This review was conducted searching libraries such as Web of Science, Scopus, ScienceDirect and Medline. Used keywords with various combinations were: "arterial aneurysms", "biology", "genetics", "proteomics", "molecular", "pathophysiology" and extracellular matrix" RESULTS: There are several genetic alterations responsible of syndromic and non-syndromic disease that predispose to aneurysm formation. ECM imbalance, mainly due to the alteration of vascular smooth muscle cells (VSMCs) homeostasis, overexpression of metalloproteinases (MPs) and cytokines activation, determines weakness of the arterial wall that dilates thus causing aneurysmal disease. Altered mechanotransduction in the ECM may also trigger and sustain anomalous cellular and biochemical signaling. Different cell population such as VSMCs, macrophages, perivascular adipose tissue (PVAT) cells, vascular wall resident stem cells (VWRSCs) are all involved at different levels CONCLUSIONS: Improving knowledge in vascular biology may help researchers and physicians in better targeting aneurysmal disease in order to better prevent and better treat such important disease.