Abdominal Aortic Aneurysm Group Research Articles

Increased arterial stiffness in males with abdominal aortic aneurysm

BackgroundAbdominal aortic aneurysm (AAA), a localized dilatation of the abdominal aorta, has a prevalence of about 1.5%–3% among 65‐ to 70‐year‐old males in Europe. AAA confers an increased risk of developing major cardiovascular events in addition to the risk of aneurysm rupture. The aim of this study was to evaluate whether the arterial wall distensibility is altered in subjects with AAA.MethodsTwo hundred and eighty‐four male subjects (182 with AAA and 102 controls) were enrolled in the study. Arterial wall distensibility was evaluated using non‐invasive applanation tonometry to measure regional pulse wave velocity between the carotid and femoral arteries and the carotid and radial arteries. In addition, blood pressure was measured, and the pulse pressure waveform was analysed.ResultsHigher aortic augmentation index (25.1% versus 20.6%; p < .001) and higher aortic pulse wave velocity (12.3 m/s versus 10.9 m/s; p < .001) were demonstrated in the AAA cohort. The slightly higher arm pulse wave velocity in the AAA group (9.4 m/s versus 9.1 m/s; p < .05) was abolished after adjusting for mean arterial blood pressure.ConclusionsMales with AAA have decreased aortic wall distensibility and enhanced reflection waves in central aorta during systole. These results imply that increased arterial wall stiffness may be a contributing factor to the overall higher cardiovascular risk seen in patients with AAA.

Characteristics and Outcomes of Ruptured Abdominal Aortic Aneurysms Below the Size Threshold for Elective Repair

The current guidelines recommend elective abdominal aortic aneurysm (AAA) repair at 5.5 cm in men and 5.0 cm in women. However, rupture occurs in patients with aneurysm size below these thresholds. This study aimed to investigate the proportion of small ruptured AAAs (rAAAs) below elective operative thresholds and to compare outcomes of repair with larger aneurysms. The 2011 to 2018 American College of Surgeons National Surgical Quality Improvement Program open and endovascular AAA repair databases were reviewed for all cases of rAAA. Patients were divided into two groups: small rAAA for those who present below size thresholds and large rAAA for the remainder. The proximal/distal extent of rAAA and the preoperative characteristics and outcomes of infrarenal rAAA were compared. Of the 1612 ruptured AAA repairs, 167 (10.4%) were small rAAAs. The proportion of small rAAA did not significantly change during the study period (P = .15; Fig). Patients in the large rAAA group were more likely to have juxtarenal or suprarenal aneurysms (27% vs 16%; P = .001). Patients in the small infrarenal rAAA group had significantly lower body mass index and were more likely to be African American and to have hypertension. Patients in the small AAA group were more likely to be assigned to American Society of Anesthesiologists class ≤3 and to undergo endovascular aneurysm repair but less likely to have hypotension on presentation. Repair of small rAAA was associated with lower bleeding, mortality, and mean operative time and higher readmission (Table). Multivariate analysis showed that rupture with hypotension, open repair, general anesthesia, age, and high American Society of Anesthesiologists class were associated with increased mortality, but aneurysm size was not. Current guidelines for elective repair based solely on AAA sac diameter fail to identify 10% of patients presenting with rupture. Ruptured AAA carries significant mortality regardless of the size of the aneurysm. Further research into sac morphology and more sensitive imaging modalities may help identify small rAAA at high risk of rupture that would benefit from elective repair.TableDemographics, comorbidities, operative characteristics, and outcomes of ruptured abdominal aortic aneurysm (rAAA)Small infrarenal rAAALarge infrarenal rAAAP valueTotal141 (100)1051 (100)Age, years <503 (2.1)40 (3.8) 51-6429 (20.5)200 (19.0) 65-7942 (29.7)311 (29.5) 80+56 (39.7)371 (35.3).86 Mean (SD)71.8 (11.6)70.8 (11.8).38Male sex105 (74.4)817 (77.7).38Functional status.16 Dependent8 (5.6)35 (3.3)BMI, kg/m2<.02 <1814 (9.9)95 (9.0) 18-2447 (33.3)217 (20.6) 25-3039 (27.6)282 (26.8) 30-3412 (8.5)188 (17.8) 35+16 (11.3)134 (12.7)BMI, kg/m2, mean (SEM)26.1 (0.6)27.8 (0.2)Height, inches, mean (SEM)67.6 (0.3)67.7 (0.1).65Weight, kg, mean (SEM)80.3 (1.8)86.8 (0.7)<.01Race White102 (72.3)790 (75.1) African American17 (12.1)53 (5.0)<.01 Other22 (15.6)208 (19.7)Comorbidities Diabetes mellitus22 (15.6)144 (13.7).54 Current smoker52 (36.8)401 (38.1).76 COPD26 (18.4)162 (15.4).35 CHF3 (2.1)32 (3.0).54 HTN106 (75.1)692 (65.8).02 Current dialysis3 (2.1)16 (1.5).59Presentation AAA diameter, mean (SEM)4.4 (0.1)8.0 (0.1)<.01 Rupture with hypotension47 (33.3)521 (49.5)<.01Surgical technique EVAR111 (78.7)685 (65.1)<.01 Open30 (21.2)366 (34.8)Anesthesia technique GA126 (89.3)959 (91.2) Other15 (10.6)92 (8.7).46ASA class ≥499 (70.2)862 (82.0)<.01Operating time, minutes, mean (SEM)163.7 (8.9)182.3 (8.9).03Complications Wound infection5 (3.5)36 (3.4).94 Pneumonia10 (7.0)100 (9.5).35 Unplanned intubation11 (7.8)93 (8.8).67 Failed vent weaning24 (17.0)224 (21.3).23 Cardiac arrest10 (7.0)103 (9.8).3 Myocardial infarction6 (4.2)90 (8.5).07 Stroke2 (1.4)20 (1.9).68 Bleeding77 (54.6)713 (67.8)<.01 DVT/thrombophlebitis4 (2.8)39 (3.7).6 Sepsis11 (7.8)108 (10.2).35 Renal failure1 (0.7)11 (1.0).7 Ischemic colitis8 (5.6)81 (7.7).38 Repeated rupture of aneurysm7 (4.9)61 (5.8).68 Lower extremity ischemia3 (2.1)50 (4.7).15 Any morbidity92 (65.2)776 (73.8).03Mortality24 (17.0)260 (24.7).04Readmission19 (13.4)60 (5.7)<.01Reoperation23 (16.3)151 (14.3).53Hospital length of stay, days (SD)9.78 (12.2)9.71 (15.2).84ASA, American Society of Anesthesiologists; BMI, body mass index; COPD, chronic obstructive pulmonary disease; CHF, congestive heart failure; DVT, deep venous thrombosis; EVAR, endovascular aneurysm repair; GA, general anesthesia, HTN, hypertension; SD, standard deviation; SEM, standard error of the mean.Values are reported as number (%) unless otherwise indicated. Boldface P values represent statistical significance. Open table in a new tab

Further evidence on the relationship between abdominal aortic aneurysm and periodontitis: A cross-sectional study.

Periodontitis is a chronic inflammatory disease characterized by Gram-negative bacteria responsible for the degradation of tissues surrounding tooth. Moreover, periopathogens can invade the bloodstream, disseminate and promote cardiovascular disease, such as the link between Porphyromonas gingivalis and atherosclerosis. The aim of this study was to explore the relationship between the severity of periodontitis and of abdominal aortic aneurysm (AAA). This cross-sectional study compared patients with stable AAA (n = 30) and patients with unstable AAA (n = 31) based on aortic diameter, growth rate, and eligibility for surgical intervention. Periodontal clinical parameters were recorded as well as the Periodontal Inflamed Surface Area and the Periodontal Index for Risk of Infectiousness (PIRI). Microbiological analyses were performed on saliva and supragingival and subgingival plaque. Quantification of Tannerella forsythia (Tf), Porphyromonas gingivalis (Pg), Aggregatibacter actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), and Prevotella intermedia (Pi) was done by quantitative polymerase chain reaction. The two AAA groups were homogeneous for age, sex, and most risk factors except hypertension and chronic obstructive pulmonary disease. Periodontal parameters were comparable but the proportion of patients with high PIRI scores was greater in those with unstable AAA (51.6% versus 23.3%). The probing depth (PD) and the proportion of PD >6 mm were positively correlated with AAA size and thrombus volume. Several associations were found between periopathogens such as Pg and AAA diameters and volumes, but no difference could be evidenced between stable and unstable AAA groups. Periodontitis was highly prevalent in both stable and unstable AAA patients. Severe and progressive periodontitis (stage IV and grade C) tended to be more frequent in the group of patients with unstable AAA. Moreover, Pg was observed in all the samples (saliva, supragingival, and subgingival plaque) and was correlated with AAA diameters and volumes. The study evidenced potential relationships between periodontitis severity and size of AAA.

All-trans retinoic acid attenuates the progression of Ang II-induced abdominal aortic aneurysms in ApoE\u2212/\u2212mice

BackgroundTo determine whether all-trans retinoic acid (ATRA) can influence the development of Angiotensin II (Ang II) induced experimental abdominal aortic aneurysms (AAAs).MethodsApolipoprotein E knock-out (ApoE−/−) mice were randomly assigned to 4 groups. Mice in the AAA and ATRA groups underwent continuous subcutaneous Ang II infusion for 28 days to induce AAA, while the Sham and Control groups were infused with saline. Systolic blood pressure was measured by the tail-cuff technique. The Control and ATRA groups received ATRA treatment. Aortic tissue samples were obtained at 28 days after surgery and evaluated by aortic diameter measurement, Western blotting, immunohistochemistry, and hematoxylin-eosin (H&E) and Verhoeff-Van Gieson (EVG) staining.ResultsThe abdominal aortic diameter was significantly reduced in the ATRA group compared with the AAA group (3 of 12 (25%) vs 9 of 12 (75%), P < 0.05), and the ATRA group exhibited reduced blood pressure on days 7, 14, and 28. Low expression of angiotensin II receptor type 1 (AT1), matrix metalloproteinase 2 (MMP2), and matrix metalloproteinase 9 (MMP9) and EVG staining revealed a significant reduction in the disruption of elastic fibers in the abdominal aortic tissue of the ATRA group compared to the AAA group. Western blot analysis indicated that protein levels of retinoic acid receptor α (RARα), MMP2, MMP9, and AT1 were dramatically affected by ATRA treatment.ConclusionsIn conclusion, ATRA attenuates the progression of Ang II-induced AAAs, possibly by downregulating MMP2, MMP9, and AT-1 expression.

Characteristics and Outcomes of Ruptured Abdominal Aortic Aneurysms Below the Size Threshold for Elective Repair

The current guidelines recommend elective abdominal aortic aneurysm (AAA) repair at 5.5 cm in men and 5.0 cm in women. However, rupture can occur in patients with aneurysm below these size thresholds. This study aims to investigate the proportion of AAA that rupture below elective operative thresholds and compare the outcomes of repair to ruptured aneurysm at larger size in a national database. The American College of Surgeons National Surgical Quality Improvement Program targeted vascular files for open AAA repair and endovascular aneurysm repair (EVAR) were reviewed for all cases of ruptured AAA between 2011 and 2018. Patients were divided into two groups: small AAA for those that presented with ruptured aneurysms below current size guidelines and large AAA for those that met size criteria for elective repair. The proportion of infrarenal AAA between the two groups was determined. The comorbidities and perioperative outcomes of infrarenal AAA repair in both groups were compared. Of the 1612 ruptured AAA repairs, 167 (10.4%) were small AAAs. The proportion of small AAA ruptures did not significantly change during the study period (P = .15) (Figure). Patients in the large AAA group were more likely to have juxtarenal or suprarenal aneurysms compared to patients in the small AAA group (27% vs 16%; P = .001). Comparison of infrarenal AAA only demonstrated that the mean small AAA (n = 141) diameter was 4.41 (range, 2-5.4cm) compared to large AAA (n = 1051) mean diameter of 8.03 cm (range, 5-20 cm) (P < .01) (Table). Patients in the small AAA group had significantly lower body mass index and mean body weight and were more likely to present with hypotension compared to patients with large AAA. Patients in the small AAA group were more likely to have American Society of Anesthesiologists classification of ≤3 and to undergo EVAR. Repair of small ruptured aneurysms was also associated with lower bleeding, mortality, and mean operative time; but had higher readmissions rates. Multivariable regression demonstrated that dependent functional status (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.2-5.3), rupture with hypotension (OR, 3.4; 95% CI, 2.5-4.8), American Society of Anesthesiologists class ≥4 (OR, 2.5; 95% CI, 1.4-4.7), and open repair compared to EVAR (OR, 1.9; 95% CI, 1.3-2.6) were associated with increased mortality but not aneurysm size. Current guidelines for elective repair based solely on AAA sac diameter fail to identify at least 10% of patients that present with rupture. Rupture of infrarenal AAA carries significant mortality regardless of the size of the aneurysm at the time of rupture. Further research into sac morphology and more sensitive imaging modalities may help identify small AAA at high risk of rupture that would benefit from elective repair.TableCharacteristics of infrarenal small and large ruptured abdominal aortic aneurysm (AAA) repairsSmall AAAn = 141Large AAAn = 1051P valueAge, years.38 <503 (2.13)40 (3.81) 51-6429 (20.57)200 (19.03) 65-7942 (29.79)311 (29.59) 80+56 (39.72)371 (35.3) Mean ± standard deviation71.8 ± 11.6570.89 ± 11.84Sex.38 Male105 (74.47)817 (77.74)Functional status.16 Dependent8 (5.67)35 (3.33)BMI <1814 (9.93)95 (9.04).07 18-2447 (33.33)217 (20.65).17 25-3039 (27.66)282 (26.83).84 30-3412 (8.51)188 (17.89).07 35+16 (11.35)134 (12.75).38 Mean26.0527.77.02Mean height67.667.7.65Mean weight177.1191.4<.01Race White102 (72.34)790 (75.17).46 Other39 (27.66)261 (24.83)Comorbidities Diabetes mellitus22 (15.6)144 (13.7).54 Current smoker52 (36.88)401 (38.15).76 COPD26 (18.44)162 (15.41).35 CHF3 (2.13)32 (3.04).54 HTN106 (75.18)692 (65.84).02 Current dialysis3 (2.13)16 (1.52).59Presentation Mean AAA diameter (cm)4.41 ± 0.068.03 ± 0.06<.01 Rupture with hypotension47 (33.33)521 (49.57)<.01Surgical technique EVAR111 (78.72)685 (65.18)<.01 Open30 (21.28)366 (34.82)Principal anesthesia technique General126 (89.36)959 (91.25) Other15 (10.64)92 (8.75)ASA class.46 ≤342 (29.79)189 (17.98) ≥499 (70.21)862 (82.02)<.01Emergency case Yes102 (72.34)888 (84.49)<.01Mean operating time, minutes163.79 ± 8.99182.39 ± 8.99.03Adverse events Wound infection5 (3.55)36 (3.43).94 Pneumonia10 (7.09)100 (9.51).35 Unplanned intubation11 (7.8)93 (8.85).67 Failed vent weaning24 (17.02)224 (21.31).23 Cardiac arrest10 (7.09)103 (9.8).3 Myocardial infarction6 (4.26)90 (8.56).07 Stroke2 (1.42)20 (1.9).68 Bleeding77 (54.61)713 (67.84)<.01 DVT/thrombophlebitis4 (2.84)39 (3.71).6 Sepsis11 (7.8)108 (10.28).35 Renal failure1 (0.71)11 (1.05).7 Ischemic colitis8 (5.67)81 (7.71).38 Repeat repair of aneurysm7 (4.96)61 (5.8).68 Lower extremity ischemia3 (2.13)50 (4.76).15Any morbidity104 (73.76)808 (76.88).41Mortality24 (17.02)260 (24.74).04Readmission within 30 days19 (13.48)60 (5.71).005Reoperation23 (16.31)151 (14.37).53Hospital length of stay, days9.78 (12.20)9.71 (15.22).84ASA, American Society of Anesthesiologists,; BMI, body mass index; CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease; DVT, deep vein thrombosis; EVAR, endovascular aneurysm repair; HTN, hypertension. Open table in a new tab

Early and long-term results of open repair of inflammatory abdominal aortic aneurysms: Comparison with a propensity score-matched cohort

ObjectiveThe aim of our study was to compare early and long-term results of open repair of patients with inflammatory abdominal aortic aneurysm (IAAA) with matched cohort of patients with abdominal aortic aneurysm (AAA). MethodsThis retrospective single-center cohort study used prospectively collected data from an institutional registry from 1786 patients between 2009 and 2015. Patients with IAAA and AAA were matched by propensity score analysis controlling for demographics, baseline comorbidities, and AAA parameters in a 1:2 ratio. Patients were followed for 5 years. ResultsThere were 76 patients with IAAA and 152 patients with AAA. Patients with IAAA had more common intraoperative lesion of intraabdominal organs (P = .04), longer in-hospital (P = .035) and intensive care (P = .048) stays and a higher in-hospital mortality rate (P = .012). There were four patients (5.26%) with in-hospital lethal outcome in IAAA there were no deaths in the AAA group. During the follow-up, there was no difference in survival (χ2 = 0.07; DF = 1; P = .80) and overall aortic related complications (χ2 = 1.25; DF = 1; P = .26); however, aortic graft infection was more frequent in IAAA group (P = .04). ConclusionsOpen repair of IAAA is challenging and comparing to AAA carries a higher perioperative risk and long-term infection rate, even in high-volume centers. The main causes of complications are intraoperative injury of adjacent organs, bleeding, and coronary events. Patients with AAA in a matched cohort showed equal long-term survival, which should be assessed in bigger registries.

Circular RNA expression profile and its potential regulative role in human abdominal aortic aneurysm

BackgroundThis study aimed to identify the differentially expressed circular RNAs (circRNAs) between human abdominal aortic aneurysm (AAA) and the control group.MethodsHigh-throughput sequencing was applied to determine the circRNA expression profiles of 4 paired aortic samples. Real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was carried out to testify 6 randomly selected dysregulated circRNAs. Kyoto Encyclopedia of Genes and Genomes and Gene ontology (GO) analysis were conducted for functional annotation of the parental genes. Additionally, interaction networks between circRNA and 5 putative microRNA (miRNA) partners were constructed.ResultsFinally, 411 differentially expressed circRNAs were discovered, including 266 downregulated and 145 upregulated circRNAs. Compared with the control group, the expression level of hsa (Homo sapiens) _circ_0005360 (LDLR) and hsa_circ_0002168 (TMEM189) were proved significantly lower in the AAA group by qRT-PCR. Regarding upregulated circRNAs, the most enriched GO molecular function, biological process and cellular component terms were poly(A) RNA binding, negative regulation of transcription from RNA polymerase II promoter and nucleoplasm, respectively. Moreover, circRNA/miRNA interaction networks showed that hsa_circ_0005360/miR-181b and hsa_circ_0002168/miR-15a axis might have a regulative role in human AAA.ConclusionsThis study revealed new circRNAs potentially related to the pathogenesis of AAA. Further experimental studies are warranted to clarify the potential molecular mechanisms.

Surgical Repair of Juxtarenal Abdominal Aortic Aneurysms and safety of Suprarenal Aortic Clamping.

Juxtarenal abdominal aortic aneurysm (AAA) comprises 15-20% of all AAAs and often requires open surgical repair (OSR) due to anatomical limitations associated with endovascular aneurysm repair (EVAR), particularly in the case of hostile proximal necks. This study aimed to evaluate short- and long-term outcomes of suprarenal clamping during OSR of juxtarenal AAAs and compare the outcomes of this technique with those of infrarenal clamping for AAAs. Between January 1 2014, and December 31 2016, 289 consecutive patients aged ≥40years underwent primary repair for infrarenal AAAs, including 141 OSRs and 148 EVARs. Of the 141 patients, 20 were excluded and totally, 121 patients were included. All patients had fusiform-type AAAs and were divided into infrarenal (N=98) or suprarenal (N=23) clamp groups. The mean follow-up period was 51.4months (95% CI: 48.6-54.2). Mean survival time was 51.4months (95% CI: 48.6-54.2). Thirty-day mortality was 0.8%, and there was no significant difference between two groups (P>.999). Renal complication in infrarenal clamp group was 4.1% and suprarenal clamp group was 4.3% (P>.999). Old age (HR: 1.084; 95% CI: 1.025-1.147; P=.005) and high ASA score (HR: 2.361; 95% CI: 1.225-4.553; P=.010) were substantially associated with in-hospital complications. Although endovascular procedures for repairing juxtarenal AAAs, such as fenestrated EVAR, have been developed, surgical repair is the standard treatment for juxtarenal AAAs. Morbidity and mortality due to open surgery were not higher in the juxtarenal AAA group than in the infrarenal AAA group. Therefore, need for suprarenal clamp should not preclude OSR and also there is continued need for training in surgical exposure of juxtarenal AAA and OSR.

Incidence, predictors, and outcomes of spinal cord ischemia in elective complex endovascular aortic repair: An analysis of health insurance claims

ObjectiveThis study aimed to determine predictors and outcomes associated with spinal cord ischemia (SCI) after elective fenestrated or branched endovascular aneurysm repair (F/BEVAR) of thoracoabdominal aortic aneurysm (TAAA), abdominal aortic aneurysm (AAA), or aortic dissection. MethodsHealth insurance claims data of Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate SCI in elective F/BEVAR performed between 2008 and 2017. The International Classification of Diseases and German Operation and Procedure Classification System were used. We stratified the results into F/BEVAR with one or two (AAA) vs three or more (TAAA) fenestrations or branches. ResultsA total of 877 patients (18.9% female; 5.8% with SCI) matching the inclusion criteria were identified during the study period. SCI occurred more often after F/BEVAR of TAAA vs AAA (10.7% vs 3.0%; P < .001). SCI was associated with female sex in the AAA group (odds ratio, 3.87; 95% confidence interval [CI], 1.25-11.15; P = .014) and with cardiac arrhythmias in the TAAA group (odds ratio, 2.98; 95% CI, 1.24-7.06; P = .013). Compared with patients without SCI, SCI patients were more likely to suffer from drug use disorders (eg, opioids, cannabinoids, sedatives) in the TAAA group (17.6% vs 2.1%; P < .05). After F/BEVAR of TAAA, the occurrence of SCI was associated with higher 90-day mortality (14.7% vs 1.1%; P < .05), longer postoperative hospital stay (22 vs 9 days; P < .05), and severe adverse events, such as acute respiratory insufficiency (44.1% vs 12.7%), acute renal failure (35.3% vs 11.3%), and pneumonia (29.4% vs 4.9%; all P < .05). In adjusted analyses, SCI was associated with worse long-term survival after F/BEVAR for TAAA (hazard ratio, 2.54; 95% CI, 1.37-4.73; P < .003). ConclusionsFemale AAA patients and TAAA patients with cardiac arrhythmias are at highest risk for development of SCI after F/BEVAR. The occurrence of this event was strongly associated with higher major complication rates and worse short-term and long-term survival. This emphasizes a need to further illuminate the value of spinal cord protection protocols in F/BEVAR.

A Comparative Study of Biomechanical and Geometrical Attributes of Abdominal Aortic Aneurysms in the Asian and Caucasian Populations.

In this work, we provide a quantitative assessment of the biomechanical and geometric features that characterize abdominal aortic aneurysm (AAA) models generated from 19 Asian and 19 Caucasian diameter-matched AAA patients. 3D patient-specific finite element models were generated and used to compute peak wall stress (PWS), 99th percentile wall stress (99th WS), and spatially averaged wall stress (AWS) for each AAA. In addition, 51 global geometric indices were calculated, which quantify the wall thickness, shape, and curvature of each AAA. The indices were correlated with 99th WS (the only biomechanical metric that exhibited significant association with geometric indices) using Spearman's correlation and subsequently with multivariate linear regression using backward elimination. For the Asian AAA group, 99th WS was highly correlated (R2 = 0.77) with three geometric indices, namely tortuosity, intraluminal thrombus volume, and area-averaged Gaussian curvature. Similarly, 99th WS in the Caucasian AAA group was highly correlated (R2 = 0.87) with six geometric indices, namely maximum AAA diameter, distal neck diameter, diameter-height ratio, minimum wall thickness variance, mode of the wall thickness variance, and area-averaged Gaussian curvature. Significant differences were found between the two groups for ten geometric indices; however, no differences were found for any of their respective biomechanical attributes. Assuming maximum AAA diameter as the most predictive metric for wall stress was found to be imprecise: 24% and 28% accuracy for the Asian and Caucasian groups, respectively. This investigation reveals that geometric indices other than maximum AAA diameter can serve as predictors of wall stress, and potentially for assessment of aneurysm rupture risk, in the Asian and Caucasian AAA populations.

Apigenin Prevent Abdominal Aortic Aneurysms Formation by Inhibiting the NF-κB Signaling Pathway.

Abdominal aortic aneurysms (AAA) is a multifactorial vascular disease with a high rate of mortality and brings heavy burden to both human and society. The pathological process behind AAA is complex. Elastin degradation, chronic inflammation, and vascular smooth muscle cell phenotypic modulation are involved in AAA formation. Apigenin (API) has gained much attention due to its specific properties, such as anti-inflammation, antioxidant, and anti-cancer effects. Previous studies have demonstrated that API exert beneficial effects on prevention of cardiovascular diseases. However, the effects of API on AAA are still unknown. Here, we for the first time evaluated API-related effects on AAA formation using a Cacl2-induced AAA model. Compared with the AAA group, treatment with API reduced the incidence of AAA, attenuated pathological expansion of the aorta, and preserved elastic fiber in a dose-dependent manner. In addition, API attenuated vascular inflammation by inhibiting activation of matrix metalloproteinase and modulated vascular smooth muscle cell contractile phenotypic transition. The preventative effect of API on AAA might be associated with the downregulation of nuclear factor-kappa B (NF-κB) activity via the IKK-dependent signaling pathway. Our findings firstly revealed that API could suppress AAA formation in a dose-dependent manner by inhibiting the NF-κB signaling pathway, and API should be considered as a promising therapeutic drug in prevention of AAA.

Plasma D-dimer as a predictor of intraluminal thrombus burden and progression of abdominal aortic aneurysm

AimIntraluminal thrombus (ILT) is presented in most abdominal aortic aneurysms (AAAs) and is suggested to promote AAA expansion. D-dimer, a breakdown product in the thrombus remodeling, may have prognostic value for AAA. This study investigated the interrelation between plasma D-dimer level, ILT volume, AAA size and progression. Main methodsThis was a retrospective observational study that involved 181 patients with infra-renal AAA. They were divided into small and large AAA groups according to AAA diameter. 24 of them had repeated abdominal computed tomography angiography (CTA) scan and were divided into slow-growing and fast-growing AAA groups according to the median value of AAA growth rate. Baseline and follow-up plasma D-dimer level, maximum diameter of AAA, total infra-renal aortic volume and ILT volume were analyzed. Key findingsPlasma D-dimer level was positively correlated with ILT volume (R = 0.382, P < 0.001) and maximum diameter of AAA (R = 0.442, P < 0.001). Increasing value of plasma D-dimer was positively associated with the accelerated growth rate of AAA (R = 0.720, P < 0.01). ILT volume showed positive correlation with maximum diameter (R = 0.859, P < 0.001) and growth rate of AAA (R = 0.490, P < 0.05). After adjusting the baseline ILT volume, the positive correlations remained to be statistically significant between plasma D-dimer level and AAA size (R = 0.200, P < 0.05), as well as increasing value of plasma D-dimer and growth rate of AAA (R = 0.642, P < 0.05). SignificancePlasma D-dimer level reflected ILT burden in AAAs. Plasma D-dimer level and ILT volume were positively correlated with AAA size. Increasing value of plasma D-dimer and baseline ILT volume could be predictors of AAA progression.

Outcome After Fenestrated and Branched Repair of Aortic Aneurysms—Device Failures Predict Reintervention Rates

Previous reports have indicated endovascular repair to be safe and effective in the treatment of complex aortic aneurysms. The endovascular technology evolves rapidly, and continuous evaluation of F/B-EVAR results is critical to detect failing techniques. Our aim was to analyze the outcome after endovascular repair of complex abdominal aortic and thoracoabdominal aneurysms. Single-center, retrospective cohort study, of all F/B-EVAR from August 2009 to December 2018. Primary outcomes were branch instability and freedom from reinterventions at 2years. Secondary outcomes were major adverse events and all-cause mortality at 30 and 90 days. A total of 72 consecutive patients were included, 55 with a complex abdominal aortic aneurysm (AAA) and 17 with a thoracoabdominal aortic aneurysm (TAAA). Two patients were operated on for rupture. A total of 219 vessels were stented through fenestrations (n=163) or branches (n=56). Median follow-up was 24months (IQR 4-24). Fractured bridging stent graft was the most common cause for reintervention, n=6. All fractures were in vessels stented with first generation BeGrafts, (6/41 BeGraft vs 0/61 other stents, P<0.01). Freedom from reinterventions at 2years was 75% and 35%, in the complex AAA and TAAA groups, respectively (P=0.04) and excluding BeGrafts 79% (cAAA) and 66% (TAAA). The most common major adverse event was spinal cord ischemia (SCI), in total 8.3% with either transient (2.8%) or permanent (5.6%) deficit. Elective mortality at 30days was 1.4% (1/70) and at 90days was 2.9% (2/70). The rate of branch instability and reintervention was high, with a clear relation to fractured first-generation BeGrafts. Mortality and major adverse event rates were low. Long-term close surveillance of bridging stent graft performance is crucial, and the endovascular community should strive to find ways to report failing materials at an early stage to avoid potentially serious complications.

Abdominal Aortic Aneurysm is an Independent Risk Factor for Subarachnoid Hemorrhage

Abstract INTRODUCTION Though both diseases share similar risk factors, little is known about the relationship between intracranial aneurysms (IA) and abdominal aortic aneurysms (AAA). Previous studies have described an increased incidence of IA in patients with AAA, though the rate of subarachnoid hemorrhage (SAH) in patients with AAA has not been described. This study evaluated the rate of SAH in patients with known AAA. METHODS We examined longitudinally linked medical claims data from a large private insurer, finding rates aneurysmal subarachnoid hemorrhage (aSAH) and secured aneurysmal SAH (saSAH) in 2004 to 2014 among patients with previously diagnosed AAA. RESULTS We identified 62 910 patients with a diagnosis of AAA with a total of 193 009 yr of at risk coverage, and compared them to age- and sex-matched controls matched 5:1. Both populations were predominantly male (70.9%) with an average age of 70.8. Rates of hypertension (69.7% vs 50.6%, P &lt; .0001) and smoking (12.8% vs 4.1%, P &lt; .0001) were higher in the AAA group compared to controls. A total of 50 admissions for aSAH were identified in AAA patients (26/100K patient years, 95% CI 19-44) and 115 admissions for aSAH in controls (7/100K patient years, 95% CI 6-9), giving an incidence rate ratio (IRR) of 3.6 (95% CI 2.6-5.0, P &lt; .0001) and a comorbidity-adjusted IRR of 2.8 (95% CI 1.9-3.9) for AAA patients. The incidence of saSAH was proportionally even higher in AAA patients than controls, 7 vs 2/100K patient years, IRR 4.5 (95% CI 3.2-6.3, P &lt; .0001). CONCLUSION The rate of SAH is elevated in patients with AAA compared with age- and sex-matched controls, even after adjustment for comorbidities. Use of AAA in screening criteria for IA should be considered.

Clinical indicators and coronary angiographic features of expansive arterial remodelling in patients with abdominal aortic aneurysms.

The co-existence of expansive arterial remodelling in both coronary arteries (CAs) and the abdominal aorta has already been reported, although the clinical indicators and quantitative analysis have not been well studied. We therefore aimed to clarify the clinical and anatomical characteristics of patients with abdominal aortic aneurysms (AAAs). 123 AAA patients who underwent coronary angiography were compared to 123 control patients selected by propensity score matching. CA diameters of all 3 vessels were measured by quantitative coronary angiographic analysis. Coronary artery ectasia (CAE) was defined as local or generalized aneurysmal change of the CAs. Excessive expansive CA remodelling was defined as the maximal diameter of the right or left circumflex artery in the upper 75th percentile (>4.8 mm). Multivariable logistic regression analyses were used to determine predictors of CAE and excessive expansive CA remodelling. The prevalences of CAE and excessive expansive CA remodelling were significantly higher in the AAA group than in the non-AAA group (28% vs. 8% and 31% vs. 19%; both p<0.05). On multivariable analysis, the presence of AAA (odds ratio (OR), 4.56; 95% confidence intervals (95%CI) 2.18–10.4) and body mass index (BMI) (OR, 1.11; 95%CI 1.03–1.21) were independently associated with CAE, and higher high-sensitivity C-reactive protein (OR, 2.19; 95%CI 1.08–4.52) and BMI (OR, 1.11; 95%CI 1.02–1.21) were independently associated with excessive expansive CA remodelling. In conclusions, this study showed a higher prevalence of ectatic CA disease in AAA patients and suggests that higher inflammation and obesity are associated with expansive arterial remodelling in coronary arteries.

Circular RNA microarray expression profile in 3,4-benzopyrene/angiotensin II-induced abdominal aortic aneurysm in mice.

Abdominal aortic aneurysm (AAA) is an unpredictable but lethal disease that poses a therapeutic dilemma. Circular RNAs (circRNAs), whose functional roles as transcriptional regulators and microRNA (miRNA) sponges have been shown in former studies, are potential biomarkers for many diseases. AAA in male C57BL/6 J mice was induced by coadministration of angiotensin II (Ang II) and 3,4-benzopyrene (BaP). The circRNA expression profiling was performed using two samples from the control group and two samples from the AAA group. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to confirm the reliability of the microarray results. Among the 14 236 detected circRNAs, 413 showed obvious expression changes (fold change ≥ 2; P < 0.05) between the BaP/Ang II-induced AAA group and control group. Of the 413 that showed significant changes, 271 were upregulated, while the other 142 were downregulated. The expression levels of 10 circRNAs were validated by qRT-PCR. The interactions of the differentially expressed circRNAs with miRNAs were predicted. Immunofluorescence showed prominent vascular smooth muscle cell apoptosis in abdominal aortic tissues in the BaP/Ang II group. Furthermore, a circRNA-miRNA coexpression network based on six apoptosis-related circRNAs was built. The genes regulated by the network mapped to several pathways, including apoptosis, the IL-17 signaling pathway, and vascular endothelial growth factor signaling pathway, all of which are related to AAA formation. This study performed circRNA expression profiling in AAA and the results specifically predicted the regulatory role of circRNAs in AAA pathogenesis.

Preferences for portable ultrasound devices: a discrete choice experiment among abdominal aortic aneurysm surveillance patients and general ultrasound patients in England

ObjectiveTo undertake an assessment of preferences as to how, where and by whom ultrasounds (US) should be performed in: (1) patients undergoing surveillance of abdominal aortic aneurysm (AAA) size (AAA...

Serum matrix metalloproteinase-9 is a valuable biomarker for identification of abdominal and thoracic aortic aneurysm: a case-control study

BackgroundMatrix metalloproteinase-9 (MMP9) has been reported to play a key role in the pathogenesis of aortic aneurysm. However, few studies have assessed serum MMP9 levels in both abdominal aortic aneurysm (AAA) and thoracic aortic aneurysm (TAA). In this study, we investigated the serum levels of MMP9 in aortic aneurysm to evaluate its predictive and diagnostic efficacy for AAA and TAA, and explored the association of MMP9 with circulating laboratory markers.MethodsA total of 296 subjects were enrolled, including 105 AAA patients, 79 TAA patients and 112 healthy controls. The levels of serum MMP9 were detected by enzyme-linked immunosorbent assay (ELISA).ResultsCompared to control group, both AAA and TAA patients had higher serum MMP9 levels in the overall comparison and subgroup analysis based on subjects aged<65 years, either male or female, hypertension, non-diabetes and non-hyperlipidemia (all P<0.05). Moreover, MMP9 levels were significantly higher in TAA group than those in AAA group in the total comparison, and this discrepancy was also found in the non-diabetes, non-hyperlipidemia and aortic diameter ≥ 5.5 cm subgroup analysis. Serum MMP9 levels were influenced by age and hypertension. There was a positive association of serum MMP9 with CRP (r = 0.33, P < 0.001) and Hcy (r = 0.199, P = 0.033). Multiple logistic analyses showed that serum MMP9 was an independent risk factor for AAA and TAA. Based on receiver operating characteristic (ROC) analysis, the area under the curve (AUC) of MMP9 for predicting TAA was 0.83 with 70% sensitivity and 91% specificity, while the AUC of MMP9 to detect AAA was 0.69 and the sensitivity and specificity were 50% and 88%.ConclusionsSerum MMP9 was closely related to the existence of aortic aneurysms and could be a valuable marker for the discrimination of aortic aneurysm, especially for TAA.

Analysis of the Correlation Between Central Obesity and Abdominal Aortic Diseases

Atherosclerosis and abdominal aortic aneurysms (AAAs) have several similar risk factors but different pathogenesis. Inflammation of the arteries is common to both. Central obesity can act as an endocrine organ through the secretion of inflammatory cytokines, and the perivascular fat has a local effect that could contribute to diseases of the abdominal aorta. Although the relation between central obesity and atherosclerosis occlusive arterial disease has been demonstrated, the correlation with AAA has conflicting results. The aim of this study was to analyze the correlation between central obesity and the presence of abdominal aortic diseases using computed tomography. Six hundred thirty-nine consecutive patients classified into 3 groups (AAA, aortic atherosclerotic occlusive disease (AAOD), and without aortic disease [control group]) who underwent computed tomography had the aorta diameter, the visceral fat area (VFA), and the subcutaneous fat area (SFA) measured at the level of third and fourth lumbar vertebrae. VFA showed no difference between the groups. SFA was lower in atherosclerotic group (AAOD) than control (P<0.01 in general and P<0.04 in male). In AAA group, we found in men that the first tertile of aorta diameter had higher VFA than third tertile (P=0.02). There was no difference in VFA between patients in AAA, AAOD, and without aortic disease groups. In men with aneurysm, there was an inverse relationship between VFA and aortic diameter. In AAOD, visceral to subcutaneous ratio is higher due to lower SFA.

Geometric analysis of ruptured and nonruptured abdominal aortic aneurysms

ObjectiveThe objective of this study was to use parameters to determine the geometric differences between ruptured abdominal aortic aneurysms (AAAs) and nonruptured AAAs. MethodsComputed tomography data of 38 ruptured AAAs and 215 electively repaired (nonruptured) AAAs were collected from multiple institutes. We compared the ruptured AAA group and nonruptured AAA group with 1:1 matching by using the Mahalanobis distance, which was calculated using the patient's age, sex, and AAA diameter. We selected the longitudinal AAA image in multiplanar reconstruction view, placed a hypothetical ellipse on the aneurysm's protruded curve, and placed a circle on the portion connecting the aneurysm and the aorta. We then measured the aspect ratio (the vertical diameter divided by the horizontal diameter) and fillet radius (the radius of arc). ResultsThe aspect ratio was significantly lower in the ruptured group than in the nonruptured group (2.02 ± 0.53 vs 2.60 ± 1.02; P = .002), as was the fillet radius (0.28 ± 0.18 vs 0.81 ± 0.44; P < .001). Receiver operating characteristic analysis revealed that the area under the curve of the aspect ratio was 0.688, and the optimal cutoff point was 2.23, with sensitivity and specificity of 0.55 and 0.76, respectively. The area under the curve of the fillet radius was 0.933, and the optimal cutoff was 0.347, with sensitivity and specificity of 0.97 and 0.87, respectively. ConclusionsThe geometric analysis performed in this study revealed that ruptured AAAs had a smaller fillet radius and smaller aspect ratio than nonruptured AAAs did.