Aneurysm Growth Rate Research Articles

Measurement of Abdominal Aortic Aneurysm Strain Using MR Deformable Image Registration: Accuracy and Relationship to Recent Aneurysm Progression.

Management of asymptomatic abdominal aortic aneurysm (AAA) based on maximum aneurysm diameter and growth rate fails to preempt many ruptures. Assessment of aortic wall biomechanical properties may improve assessment of progression and rupture risk. This study aimed to assess the accuracy of AAA wall strain measured by cine magnetic resonance imaging (MRI) deformable image registration (MR strain) and investigate its relationship with recent AAA progression. The MR strain accuracy was evaluated in silico against ground truth strain in 54 synthetic MRIs generated from a finite element model simulation of an AAA patient's abdomen for different aortic pulse pressures, tissue motions, signal intensity variations, and image noise. Evaluation included bias with 95% confidence interval (CI) and correlation analysis. Association of MR strain with AAA growth rate was assessed in 25 consecutive patients with >6 months of prior surveillance, for whom cine balanced steady-state free-precession imaging was acquired at the level of the AAA as well as the proximal, normal-caliber aorta. Univariate and multivariate regressions were used to associate growth rate with clinical variables, maximum AAA diameter (D max ), and peak circumferential MR strain through the cardiac cycle. The MR strain interoperator variability was assessed using bias with 95% CI, intraclass correlation coefficient, and coefficient of variation. In silico experiments revealed an MR strain bias of 0.48% ± 0.42% and a slope of correlation to ground truth strain of 0.963. In vivo, AAA MR strain (1.2% ± 0.6%) was highly reproducible (bias ± 95% CI, 0.03% ± 0.31%; intraclass correlation coefficient, 97.8%; coefficient of variation, 7.14%) and was lower than in the nonaneurysmal aorta (2.4% ± 1.7%). D max ( β = 0.087) and MR strain ( β = -1.563) were both associated with AAA growth rate. The MR strain remained an independent factor associated with growth rate ( β = -0.904) after controlling for D max . Deformable image registration analysis can accurately measure the circumferential strain of the AAA wall from standard cine MRI and may offer patient-specific insight regarding AAA progression.

The effects of statin therapy on aneurysm size, growth rate, and matrix metalloproteinases-9 levels in patients with aortic aneurysm: a systematic review and meta-analysis

BackgroundAortic aneurysm enlargement over time causes rupture, which frequently results in death. The family of proteases known as matrix metalloproteinases (MMP) is assumed to be proteolytic activity involved in the growth of aortic aneurysms. Statins are pleiotropic lipid-lowering medications with anti-inflammatory action. Statins can lower aneurysmal enlargement and MMP secretion, according to a number of studies, however the evidence is still up for debate. The purpose of this study is to assess how statins affect aortic aneurysm patient's aneurysm diameter size, growth rate, and MMP-9 levels.MethodsFrom January 2000 to December 2022, electronic journal searches in PubMed, ScienceDirect, and Cochrane were conducted to discover papers evaluating the effects of statin treatment in patients with aortic aneurysm. Aneurysm diameter size, growth rate, and MMP-9 levels were the outcomes we were looking for. Meta-analyses were run on the included studies, and mean differences (MD) and 95% CIs were calculated with Review Manager v5.4.ResultsOur analysis includes a total of ten research. Statin medication substantially reduced aneurysm diameter size by 0.30 mm (P = 0.04; MD − 0.30; 95% CI − 0.58 to − 0.01) and growth rate by 0.34 mm/year (P < 0.00001; MD − 0.34; 95% CI − 0.40 to − 0.29) compared to placebo. There was no significant change in MMP-9 concentrations between individuals with aortic aneurysm who took a statin and those who did not.ConclusionOverall, this meta-analysis demonstrates that statin medication is considerably helpful in reducing aneurysm diameter size and aneurysmal growth rate in individuals with aortic aneurysm.

Investigation of commonly used aortic aneurysm growth rate metrics: Comparing their suitability for clinical and research applications.

An aneurysm is a pathological widening of a blood vessel. Aneurysms of the aorta are often asymptomatic until they rupture, killing approximately 10,000 Americans per year. Fortunately, rupture can be prevented through early detection and surgical repair. However, surgical risk outweighs rupture risk for small aortic aneurysms, necessitating a policy of surveillance. Understanding the growth rate of aneurysms is essential for determining appropriate surveillance windows. Further, identifying risk factors for fast growth can help identify potential interventions. However, studies in the literature have applied many different methods for defining the growth rate of abdominal aortic aneurysms. It is unclear which of these methods is most accurate and clinically meaningful, and whether these heterogeneous methodologies may have contributed to the varied results reported in the literature. To help future researchers best plan their studies and to help clinicians interpret existing studies, we compared five different models of aneurysmal growth rate. We examined their noise tolerance, temporal bias, predictive accuracy, and statistical power to detect risk factors. We found that hierarchical mixed effects models were more noise tolerant than traditional, unpooled models. We also found that linear models were sensitive to temporal bias, assigning lower growth rates to aneurysms that were detected earlier in their course. Our exponential mixed model was noise-tolerant, resistant to temporal bias, and detected the greatest number of clinical risk factors. We conclude that exponential mixed models may be optimal for large studies. Because our results suggest that choice of method can materially impact a study's findings, we recommend that future studies clearly state the method used and demonstrate its appropriateness.

Early Relative Growth Rate of Abdominal Aortic Aneurysms and Future Risk of Rupture or Repair

This study aimed to test whether the relative growth rate of subthreshold abdominal aortic aneurysms (AAAs) in the first 24 months of surveillance predicts the risk of future rupture or repair. This was a single centre retrospective observational analysis of all small (< 45 mm diameter) and medium (45 - 54 mm in men, 45 - 50 mm in women) AAAs entered into ultrasound surveillance between January 2002 and December 2019, which received ≥ 24 months of surveillance. Relative growth rates were calculated from measurements taken in the first 24 months of surveillance. The Kaplan-Meier method was used to estimate intervention and rupture free proportions five years following diagnosis for AAAs growing by < 5% and by ≥ 5% in the first 24 months of surveillance. Multivariable Cox regression analysis was used to further analyse this relationship by adjusting for factors found to be significantly associated with outcome in univariable analysis. A total of 556 patients with AAAs (409 men, 147 women) were followed for ≥ 24 months. This included 431 small AAAs. Of these, 109 (25.3%) grew by < 5% in the first 24 months of surveillance and had a cumulative event free proportion of 0.98 ± 0.05 at five years compared with 0.78 ± 0.05 for the ≥ 5% growth group (p < .001). Of 125 medium AAAs, 26 (20.8%) grew by < 5% in the first 24 months of surveillance and had a cumulative event free proportion of 0.73 ± 0.11 at five years compared with 0.29 ± 0.13 for the ≥ 5% growth group (p= .024). Baseline diameter and early relative growth rate were strongly and independently predictive of future intervention or rupture with hazard ratios of 9.16 (95% CI 5.98 - 14.03, p < .001) and 4.46 (95% CI 2.45 - 8.14, p < .001), respectively. The results suggest that slow expansion of small (< 45 mm) AAAs observed over an isolated 24 month period is indicative of a very low risk of rupture or repair in the medium term. Isolated growth rates may be a useful tool with which to triage low risk AAAs and prevent unnecessary surveillance.

Clinical, 3D Morphological, and Hemodynamic Risk Factors for Instability of Unruptured Intracranial Aneurysms.

Neurosurgeons can manage unruptured intracranial aneurysms (UIAs). However, the stability of UIAs under follow-up remains uncertain. This study aimed to examine the risk factors associated with the instability (rupture or growth) of UIAs during follow-up. We obtained information on patients with UIA who underwent ≥ 6months of the time of flight-magnetic resonance angiography (TOF-MRA) imaging follow-up in two centers. Computer-assisted semi-automated measurement (CASAM) techniques were used for recording morphological parameters and determining the growth of these aneurysms. We also recorded hemodynamic parameters at the beginning of the follow-up. The univariate and multivariate Cox regression analyses were performed to calculate hazard ratios with corresponding 95% confidence intervals for the clinical, morphological, and hemodynamic risk factors for aneurysm instability. A total of 304aneurysms from 263patients (80.4%) were included for analysis. The annual aneurysm growth rate was 4.7%. Significant predictive factors for aneurysm instability in the multivariate analysis were as follows: poorly controlled hypertension (hazard ratio (HR), 2.97 (95% CI, 1.27-6.98), P = 0.012); aneurysms located on posterior circulation (HR, 7.81 (95% CI, 2.28-26.73), P = 0.001), posterior communication artery (HR, 3.01 (95% CI, 1.07-8.46), P = 0.036), and cavernous carotid artery (HR, 3.78 (95% CI, 1.18-12.17), P = 0.026); and size ratio ≥ 0.87 (HR, 2.54 (95% CI, 1.14-5.68), P = 0.023). The management of UIAs should focus on the control of hypertension during the follow-up. Aneurysms on the posterior communicating artery, posterior circulation, and cavernous carotid arteries require intensive surveillance or timely treatment.

Computer-aided shape features extraction and regression models for predicting the ascending aortic aneurysm growth rate

Objective:ascending aortic aneurysm growth prediction is still challenging in clinics. In this study, we evaluate and compare the ability of local and global shape features to predict the ascending aortic aneurysm growth. Material and methods:70 patients with aneurysm, for which two 3D acquisitions were available, are included. Following segmentation, three local shape features are computed: (1) the ratio between maximum diameter and length of the ascending aorta centerline, (2) the ratio between the length of external and internal lines on the ascending aorta and (3) the tortuosity of the ascending tract. By exploiting longitudinal data, the aneurysm growth rate is derived. Using radial basis function mesh morphing, iso-topological surface meshes are created. Statistical shape analysis is performed through unsupervised principal component analysis (PCA) and supervised partial least squares (PLS). Two types of global shape features are identified: three PCA-derived and three PLS-based shape modes. Three regression models are set for growth prediction: two based on gaussian support vector machine using local and PCA-derived global shape features; the third is a PLS linear regression model based on the related global shape features. The prediction results are assessed and the aortic shapes most prone to growth are identified. Results:the prediction root mean square error from leave-one-out cross-validation is: 0.112 mm/month, 0.083 mm/month and 0.066 mm/month for local, PCA-based and PLS-derived shape features, respectively. Aneurysms close to the root with a large initial diameter report faster growth. Conclusion:global shape features might provide an important contribution for predicting the aneurysm growth.

Abdominal aortic aneurysm growth rates are not correlated to body surface area in screened men.

Screening for abdominal aortic aneurysm (AAA) in 65-year-old males reduces aneurysm related mortality. Infrarenal aortic diameter (IAD) has been shown to correlate to body surface area (BSA) which could influence diagnostic criteria for AAA. This study investigates whether AAA growth rates are also dependent on BSA, as that might have potential effects on surveillance of small AAAs. We conducted a retrospective, single center cohort study of 301 men with screening detected AAA between 2010-2017 with surveillance to 2021. AAA growth rates were analyzed in relation to the subject's BSA, smoking habits, and diabetic disease using a linear mixed-effects model. All men were offered smoking cessation program, optimized medical treatment, and advice on physical activity. The screening program included 28,784 men. Of the 22,819 (79%) attending the examinations, 374 men (1.6%) were found to have an AAA out of which 301 men had undergone two or more examinations during surveillance and were included with a median follow-up of 1846 days (IQR: 1 399). Mean unadjusted AAA growth rate was 1.60 mm/year (95% CI: 1.41-1.80). Diabetes mellitus had a statistically significant negative impact, smoking had a statistically significant positive impact on AAA growth rates whereas no correlation between AAA growth rate and BSA could be found. Body surface area could not be found to have a statistically significant correlation to AAA growth rates. The impact of smoking and diabetes on AAA growth rates remains similar to previously reported.

Cancer, cancer treatment and aneurysmatic ascending aorta growth within a retrospective single center study.

Background: Multi-morbidity poses a substantial challenge for health care in an aging population. Recent studies did not provide evidence for general side effects of anti-cancer therapy regarding the growth rate of coincident abdominal aortic aneurysms, although it was suggested that specific therapeutic substances might accelerate growth. Aneurysm pathology, however, differs with respect to localization. Hence, we present the first ever analysis on the association of cancer and cancer therapy with growth alteration of aneurysms of the ascending aorta (AscAA). Patients and methods: A retrospective single-center identification of AscAA+cancer patients was performed in the institutional picture archiving and communication system (PACS). Included were all patients with ≥2 CT angiograms over ≥6 months and additional malignancy. Clinical data and aneurysm diameters were retrieved and analyzed for an association of cancer (stratified by tumor entity) or cancer therapy (stratified by several classes of chemotherapeutic agents and radiation therapy) with annual growth rate, respectively. Statistics included t-test, Wilcoxon test, and a linear regression model accounting for initial AscAA diameter and type of treatment. Results: From 2003 to 2021, 151 patients (median age 70 years; 85% male) with AscAA and coincident 163 malignancies were identified. Prostate (37%) and hematologic cancer (17%) were most frequent. One-hundred-eleven patients (74%) received chemotherapy and 75 patients (50%) had radiation. After exclusion of six patients with an initial AscAA diameter >55 mm, the average annual AscAA growth rate was 0.18±0.64 mm/year, with only 12 patients experiencing a growth rate >1mm/year. Neither tumor entity nor radiation or chemotherapy - alone or in combination - were significantly associated with an alteration of the annual AscAA growth rate. Likewise, a subanalysis for singular chemotherapeutic agents did not reveal a specific association with AscAA growth alteration. Conclusions: Growth rates of AscAA are low in this cohort with coincident malignancy. Cancer and/or chemotherapy or radiation are not associated with an alteration of the annual growth rate. Additional control examinations seem unnecessary.

Infrarenal Remains Infrarenal-EVAR Suitability of Small AAA Is Rarely Compromised despite Morphological Changes during Surveillance.

The aim was to analyze small abdominal aortic aneurysm (AAA) morphology during surveillance with regard to standard endovascular aortic repair (EVAR) suitability. This retrospective single-center study included all patients (n = 52, 48 male, 70 ± 8 years) with asymptomatic AAA ≤ 5.4 cm undergoing ≥2 computed tomography angiography(CTA)/magnetic resonance imaging (MRI) studies (interval: ≥6 months) between 2010 and 2018. Aneurysm diameter, neck quality (shape, length, angulation, thrombus/calcification), aneurysm thrombus, and distal landing zone diameters were compared between first and last CTA/MRI. Resulting treatment plan changes were determined. Neck shortening occurred in 25 AAA (mean rate: 2.0 ± 4.2 mm/year). Neck thrombus, present in 31 patients initially, increased in 16. Average AAA diameters were 47.7 ± 9.3 mm and 56.3 ± 11.6 mm on first and last CTA/MRI, mean aneurysm growth rate was 4.2 mm/year. Aneurysm thrombus was present in 46 patients primarily, increasing in 32. Neck thrombus growth and neck length change, aneurysm thrombus amount and aneurysm growth and aneurysm growth and neck angulation were significantly correlated. A total of 46 (88%) patients underwent open (12/46) or endovascular (34/46) surgery. The planned procedure changed from EVAR to fenestrated EVAR in two patients and from double to triple fenestrated EVAR in one. Thus, standard EVAR suitability was predominantly maintained as the threshold diameter for surgery was reached despite morphological changes. Consecutively, a possibly different pathogenesis of infra- versus suprarenal AAA merits further investigation.

165 Antithrombotic Therapy for Aortic and Peripheral Artery Aneurysms: A Systematic Review and Meta-Analysis

Abstract Aim This systematic review and meta-analysis aimed to assess the impact of antithrombotic agents on extracranial aneurysms under surveillance or undergoing intervention. Method Medline, Embase, and CENTRAL databases were searched. Randomised-controlled trials and observational studies investigating the effect of antithrombotic therapy on clinical outcomes for patients with aortic or extracranial peripheral arterial aneurysms were included. Aneurysm growth rate, major adverse cardiovascular or limb events, mortality, endoleaks, re-intervention rates, and other outcomes were captured. Results Fifty-seven studies involving 121,451 patients were included (26 antiplatelets, 12 anticoagulants, 16 any antithrombotic agent(s), 2 intra-operative heparin). Aspirin reduced growth rates of aortic aneurysms under surveillance (mean difference -0.9mm/y, 95%CI -1.74 to -0.07, p=0.03; GRADE certainty: moderate). For aortic aneurysms undergoing intervention, antithrombotics increased 30-day mortality (odds ratio [OR] 2.30, 95%CI 1.51 to 3.51, p&amp;lt;0.001; GRADE certainty: moderate). Antiplatelets reduced long-term all-cause mortality (hazard ratio [HR] 0.84, 95%CI 0.76 to 0.92, p&amp;lt;0.001; GRADE certainty: moderate), whilst anticoagulants increased this risk (HR 1.64, 95%CI 1.14 to 2.37, p=0.008; GRADE certainty: very low). Anticoagulants increased incidence of endoleaks under 3 years, and re-intervention rates (p&amp;lt;0.05 for all). Antithrombotic agents did not significantly affect rupture rates in aortic aneurysms. Meta-analysis was not possible for ruptured aneurysms and popliteal aneurysms. Conclusions There is moderate quality evidence that aspirin reduces aneurysm growth rates. Antiplatelet agents reduced all-cause mortality in aneurysms after intervention; whilst anticoagulants increased this risk, along with endoleaks and re-interventions. Well-designed trials are required to determine therapeutic benefits of antithrombotic agents for patients with aneurysms.

548 A 10-Year Longitudinal Cohort Study Assessing Growth Rates and Surveillance Intervals for Common Iliac Artery Aneurysms

Abstract Aim The European Society for Vascular Surgery defines common iliac artery (CIA) aneurysms as greater than 1.8cm in men and 1.5cm in women. Their reported growth rate is 1–4mm/year depending on their diameter. This study aimed to assess the natural history and surveillance intervals for CIA aneurysms as intervention threshold is based on low-quality evidence. Method Patients diagnosed with an IAA at a single vascular centre between 1st January 2010 and 31st August 2021 were identified from a prospectively collected departmental database and Caldicott-approved data collection performed. The primary outcomes included diameter-based mean aneurysm growth rates and median surveillance intervals. Statistical analysis with SPSS® was performed using chi-squared tests. Results Of the 203 patients included, 90.6% were men and median (IQR) age at detection was 77 (71–83). IAA were located in the CIA (85.2%), IIA (21.7%) and EIA (2.0%) with the majority being asymptomatic (78.8%). CT was most frequently used as the imaging modality for IAA surveillance (66.3%), followed by ultrasound scan (29.8%) and MRA (3.9%). Growth rate for CIA aneurysms measuring 1.0–1.9cm were -2.1mm/year, 2.0–2.9cm were 0.8mm/year, 3.0–3.9cm were 3.5mm/year, 4.0–4.9cm were 9.4mm/year, 5.0–5.9cm were 2.9mm/year and &amp;gt;6.0cm were 13.8mm/year. Median surveillance intervals for CIA aneurysms at 1.0–1.9cm were 12-monthly, 2.0–2.9cm were 11-monthly, 3.0–3.9cm were 5-monthly, 4.0–4.9cm were 5-monthly, 5.0–5.9cm were 5.5-monthly and &amp;gt;6.0cm were 14.5-monthly. Mean(SD) CIA diameter at rupture was 4.6 (2.4)cm. Conclusions CIA aneurysms demonstrate faster growth rates as they enlarge and may require more frequent clinical assessments, surveillance, and consideration for repair prior to rupture.

Neural operator learning of heterogeneous mechanobiological insults contributing to aortic aneurysms.

Thoracic aortic aneurysm (TAA) is a localized dilatation of the aorta that can lead to life-threatening dissection or rupture. In vivo assessments of TAA progression are largely limited to measurements of aneurysm size and growth rate. There is promise, however, that computational modelling of the evolving biomechanics of the aorta could predict future geometry and properties from initiating mechanobiological insults. We present an integrated framework to train a deep operator network (DeepONet)-based surrogate model to identify TAA contributing factors using synthetic finite-element-based datasets. For training, we employ a constrained mixture model of aortic growth and remodelling to generate maps of local aortic dilatation and distensibility for multiple TAA risk factors. We evaluate the performance of the surrogate model for insult distributions varying from fusiform (analytically defined) to complex (randomly generated). We propose two frameworks, one trained on sparse information and one on full-field greyscale images, to gain insight into a preferred neural operator-based approach. We show that this continuous learning approach can predict the patient-specific insult profile associated with any given dilatation and distensibility map with high accuracy, particularly when based on full-field images. Our findings demonstrate the feasibility of applying DeepONet to support transfer learning of patient-specific inputs to predict TAA progression.

O075 Antithrombotic therapy for aortic and peripheral artery aneurysms: a systematic review and meta-analysis

Abstract Introduction The role of antithrombotic agents in aneurysm progression and outcomes following surgical or endovascular intervention is unclear. Methods A systematic review and meta-analysis was performed. Medline, Embase, and CENTRAL databases were searched. Randomised-controlled trials and observational studies investigating the effect of antithrombotic therapy on clinical outcomes for patients with aortic or extracranial peripheral arterial aneurysms were included. Aneurysm growth rate, major adverse cardiovascular or limb events, mortality, endoleaks, re-intervention rates, and other outcomes were captured. Results Fifty-seven studies involving 121,451 patients were included (26 antiplatelets, 12 anticoagulants, 16 any antithrombotic agent(s), 2 intra-operative heparin). Aspirin reduced growth rates of aortic aneurysms under surveillance (mean difference -0.9mm/y, 95%CI -1.74 to -0.07, p=0.03; GRADE certainty: moderate). For aortic aneurysms undergoing intervention, anti-thrombotics increased 30-day mortality (odds ratio [OR] 2.30, 95%CI 1.51 to 3.51, p&amp;lt;0.001; GRADE certainty: moderate). Antiplatelets reduced long-term all-cause mortality (hazard ratio [HR] 0.84, 95%CI 0.76 to 0.92, p&amp;lt;0.001; GRADE certainty: moderate), whilst anticoagulants increased this risk (HR 1.64, 95%CI 1.14 to 2.37, p=0.008; GRADE certainty: very low). Anticoagulants increased incidence of endoleaks under 3 years, and re-intervention rates (p&amp;lt;0.05 for all). Antithrombotic agents did not significantly affect rupture rates in aortic aneurysms. Meta-analysis was not possible for ruptured aneurysms and popliteal aneurysms. Conclusion There is moderate quality evidence that aspirin reduces aneurysm growth rates. Antiplatelet agents reduced all-cause mortality in aneurysms after intervention; whilst anticoagulants increased this risk, along with endoleaks and re-interventions. Well-designed trials are required to determine therapeutic benefits of antithrombotic agents for patients with aneurysms. Take-home message Antiplatelets may have a role in reducing aneurysm growth rates and all-cause mortality; whilst anticoagulants are associated with increased mortality, endoleaks, and re-interventions. Well-designed trials are required to determine therapeutic benefits of antithrombotic agents for patients with aneurysms.

O072 A 10-year longitudinal cohort study assessing growth rates and surveillance intervals for common iliac artery aneurysms

Abstract Introduction European Society for Vascular Surgery defines common iliac artery (CIA) aneurysms as greater than 1.8cm in men and 1.5cm in women. Reported growth rate is 1–4mm/year depending on their diameter. This study assessed the natural history and surveillance intervals for CIA aneurysms as intervention threshold is based on low-quality evidence. Methods Patients with an IAA at a single vascular centre between 1st January 2010 and 31st August 2021 were identified from a prospectively collected departmental database and Caldicott-approved data collection performed. The primary outcomes included diameter-based mean aneurysm growth rates and median surveillance intervals. Statistical analysis with SPSS® was performed using chi squared tests. Results Of 203 patients included, 90.6% were men and median (IQR) age at detection was 77(71–83). IAA were located in the CIA (85.2%), IIA (21.7%) and EIA (2.0%) with the majority being asymptomatic (78.8%). CT was most frequently used as the imaging modality for IAA surveillance (66.3%), followed by ultrasound scan (29.8%) and MRA (3.9%). Growth rate for CIA aneurysms measuring 1.0–1.9cm were -2.1mm/year, 2.0–2.9cm were 0.8mm/year, 3.0–3.9cm were 3.5mm/year, 4.0–4.9cm were 9.4mm/year, 5.0–5.9cm were 2.9mm/year and &amp;gt;6.0cm were 13.8mm/year. Median surveillance intervals for CIA aneurysms at 1.0–1.9cm were 12-monthly, 2.0–2.9cm were 11-monthly, 3.0–3.9cm were 5-monthly, 4.0–4.9cm were 5-monthly, 5.0–5.9cm were 5.5-monthly and &amp;gt;6.0cm were 14.5-monthly. Mean (SD) CIA diameter at rupture was 4.6 (2.4)cm. Conclusion CIA aneurysms demonstrate faster growth rates as they enlarge and may require more frequent clinical assessments, surveillance and consideration for repair prior to rupture. Take-home message CIA aneurysms demonstrate faster growth rates as they enlarge and may require more frequent clinical assessments, surveillance and consideration for repair prior to rupture.

Radiation and Chemotherapy are Associated with Altered Aortic Aneurysm Growth in Patients with Cancer: Impact of Synchronous Cancer and Aortic Aneurysm

The purpose of this study was to assess the associations between malignancy, therapeutic regimens, and aorto-iliac aneurysm (i.e., abdominal aortic aneurysm [AAA]) growth rates. A retrospective single centre analysis identified patients with an AAA plus cancer. Patients who had two or more computed tomography angiograms over six months or more and additional malignancy were included. Clinical data and aneurysm diameters were analysed. AAA growth under cancer therapy (chemotherapy or radiation) was compared with a non-cancer AAA control cohort and to meta-analysis data. Statistics included t tests and a linear regression model with correction for initial aortic diameter and type of treatment. From 2003 to 2020, 217 patients (median age 70 years; 92% male) with 246 aneurysms (58.8% AAA) and 238 malignancies were identified. Prostate (26.7%) and lung (15.7%) cancer were most frequently seen. One hundred and fifty-seven patients (72.3%) received chemotherapy, 105 patients (48.4%) radiation, and 79 (36.4%) both. Annual AAA growth (mean ± standard deviation) was not statistically significantly different for cancer and non-cancer patients (2.0 ± 2.3 vs. 2.8 ± 2.1 mm/year; p= .20). However, subgroup analyses revealed that radiation was associated with a statistically significantly reduced mean aneurysm growth rate compared with cancer patients without radiation (1.1 ± 1.3 vs. 1.6 ± 2.1 mm/year; p= .046) and to the non-cancer control cohort (1.7 ± 1.9 vs. 2.8 ± 2.1 mm/year; p= .007). Administration of antimetabolites resulted in statistically significantly increased AAA growth (+ 0.9 mm/year; p= .011), while topoisomerase inhibitors (- 0.8 mm/year; p= .17) and anti-androgens (- 0.5 mm/year; p= .27) showed a possible trend for reduced growth. Similar observations were noted for iliac aneurysms (n= 85). Additionally, the effects persisted for chemotherapy combinations (2.6 ± 1.4 substances/patient). Patients with cancer and concomitant aortic aneurysms may require intensified monitoring when undergoing specific therapies, such as antimetabolite treatment, as they may experience an increased aneurysm growth rate. Radiation may be associated with reduced aneurysm growth.

Abdominal aortic aneurysm growth rates in patients undergoing local ultrasound surveillance.

Abdominal aortic aneurysm ultrasound surveillance varies between hospitals in the United Kingdom. University Hospitals Bristol and Weston adopt a 6-monthly surveillance interval for 4.5-4.9 cm abdominal aortic aneurysm, which is a deviation from nationally recommended 3-monthly intervals. Assessment of abdominal aortic aneurysm growth rate, and the concurrent impact of abdominal aortic aneurysm risk factors and medications prescribed for risk factors, may inform whether this change in surveillance intervals is safe and appropriate. This analysis was conducted retrospectively. A total of 1312 abdominal aortic aneurysm ultrasound scans from 315 patients between January 2015 and March 2020 were split into 0.5 cm groups, ranging from 3.0 to 5.5 cm. Abdominal aortic aneurysm growth rate was assessed with one-way analysis of variance. The impact of risk factors and risk factor medication on abdominal aortic aneurysm growth rate was analysed using multivariate and univariate linear regression and Kruskal-Wallis tests. Patient cause of death among surveillance patients was recorded. Abdominal aortic aneurysm growth rate was significantly associated with increased abdominal aortic aneurysm diameter (p < 0.001). There was a significant whole-group reduction in growth rate from 0.29 to 0.19 cm/year in diabetics compared to non-diabetics (p = 0.02), supported by univariate linear regression (p = 0.04). In addition, gliclazide patients had lower growth rate compared to patients not on the medication (p = 0.04). One abdominal aortic aneurysm rupture occurred <5.5 cm resulting in death. Abdominal aortic aneurysm measuring 4.5-4.9 cm had a mean growth rate of 0.3 cm/year (± 0.18 cm/year). Therefore, mean growth rate and variability suggest patients are unlikely to surpass surgical threshold of 5.5 cm between the 6-monthly surveillance scans, supported by low rupture rates. This suggests the surveillance interval for 4.5-4.9 cm abdominal aortic aneurysm is a safe and appropriate deviation from national guidance. In addition, it may be pertinent to consider diabetic status when designing surveillance intervals.

Women Experience Higher Rates of Mortality Following Thoracic and Complex Endovascular Aneurysm Repair

Thoracic and complex endovascular aortic repair (TCEVAR) has been increasingly adopted in the treatment of thoracic and thoracoabdominal aorta aneurysms, offering a less-invasive approach for patients with the appropriate anatomy. Women usually present with a smaller aortic diameter. However, they also usually have greater aneurysm growth rates. How sex can affect the postoperative and short-term outcomes after TCEVAR has not been well reported. The aim of this study was to assess the outcomes for female and male patients undergoing TCEVAR for the treatment of thoracic and thoracoabdominal aneurysms in a Medicare-linked database.

Natural history of bicuspid aortic valves and ascending aortic aneurysms: Aortic center experience.

The American Association of Thoracic Surgery published guidelines in 2018 encouraging regular surveillance rather than surgical intervention for ascending aortic aneurysms under 5.5 cm in both bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) patients. Since then, there have been limited studies reporting outcomes, especially by valve type. We aimed to analyze clinical outcomes including survival and aortic events in a cohort of BAV and TAV patients with ascending aortic aneurisms followed conservatively with routine computerized tomography (CT) surveillance per current guidelines. We followed 188 patients in our clinic between 2016 and 2019; 147 had two or more CT scans which allowed measurement of aortic growth. Echocardiogram data was evaluated for each patient. We identified similar cohorts of BAV (n = 32) and TAV (n = 64) patients matched by age, sex, hypertension, smoking history, family history of aortic disease, coronary artery disease, and hyperlipidemia. Univariate and multivariate analyses of the unmatched cohorts were performed. The mean aneurysm size was 4.3 ± 0.58 cm with 95% confidence interval (3.14, 5.46). This did not differ between BAV and TAV patients, nor did aneurysm growth rates. Overall adverse event rate (dissection, rupture, and death) was low for the entire cohort (BAV group, 3% and TAV group, 3.5%). Survival at 10 years for the entire cohort was 90 ± 32%. Regardless of aortic valve type, there was a similar natural history and low adverse event rate. In the absence of risk factors, conservative management can be accomplished with minimal risk to the patient.

Contemporary Management of Abdominal Aortic Aneurysms.

Abdominal aortic aneurysms (AAA) can carry extremely high mortality rates and most will only present with symptoms with impending rupture. We present an overview of management of this disease process starting with screening, to medical management, surveillance and treatment options currently available, as well as those being studied for future use. Screening has been proven to reduce the mortality rate. There still remains a paucity of data to support medical therapies to help mitigate the rate of aneurysm growth and prevent rupture. However, on the topic of repair, there have been advancements in endovascular devices which have broadened the scope of treatment for patients with anatomy not amenable to standard endovascular repair or those who are not suitable candidates for open surgical repair. Appropriate surveillance, risk factor modification, and operative repair, when indicated, are the cornerstones of contemporary management of AAAs. Advancements in endovascular technologies have allowed us to treat more patients. Further research is warranted on non-operative medical therapies.

Aneurysm size and blood pressure severity in patients with intracranial aneurysms and sleep apnea.

Obstructive sleep apnea is a risk factor for hypertension. Hypertension is associated with aneurysm formation, growth, and rupture of intracranial aneurysm (IA). Retrospectively, symptoms of obstructive sleep apnea are more prevalent in patients with IAs. Studies investigating the prevalence and effect of objectively measured sleep apnea in these patients are sparse. We report on the baseline data of an ongoing prospective study. We cross-sectionally analyzed whether obstructive sleep apnea was associated with larger IAs and increased need for antihypertensive medications in a population of patients with unruptured IA. 130 adult (≥ 18 years) patients with unruptured IAs were recruited. Patients with ischemic stroke or intracranial hemorrhage within 3 months prior to screening were excluded. We assessed obstructive sleep apnea by full-night respiratory polygraphy. Aneurysm size and antihypertensive medication-as a surrogate parameter for the severity of hypertension-were compared between patients with and without obstructive sleep apnea (apnea-hypopnea index >5 events/h). Aneurysm growth and rupture rate were retrospectively analyzed. 101 patients completed the study protocol. Obstructive sleep apnea was diagnosed in 68.0% (17) of male and 34.2% (26) of female participants and associated with more severe hypertension (1.536 ± 0.2 vs 0.74 ± 0.1 drugs; P = .01) and larger aneurysms (6.9 ± 1.0 vs 3.8 ± 0.5 mm; P = .01). Patients with obstructive sleep apnea had more antihypertensive medication and larger IAs, probably due to accelerated aneurysm growth. Sleep apnea should be considered in patients with IAs. More research is needed to investigate the effects of sleep apnea on IAs and aneurysm outcome. Registry: ClinicalTrials.gov; Name: Incidence and Effects of Sleep Apnea on Intracerebral Aneurysms-IESA Study; URL: https://clinicaltrials.gov/ct2/show/NCT02880059; Identifier: NCT02880059. Zaremba S, Albus L, Hadjiathanasiou A, Vatter H, Wüllner U, Güresir E. Aneurysm size and blood pressure severity in patients with intracranial aneurysms and sleep apnea. J Clin Sleep Med. 2022;18(6):1539-1545.