The real-world incidence and predictors of sac regression in patients with infrarenal abdominal aortic aneurysm after standard EVAR

OBJECTIVE

Sac regression (SR) is a surrogate marker of satisfied endovascular aneurysm repair (EVAR). This research aims to investigate the incidence and predictors of SR in a Chinese population.

DESIGN

Single centre retrospective cohort study.

METHODS

Consecutive patients with infrarenal abdominal aortic aneurysms (AAAs) who underwent standard EVAR were retrospectively reviewed. SR was defined as sac shrinkage > 5 mm on computed tomography images, while major SR (MaSR) was ≥ 10 mm sac shrinkage. The cumulative rate was calculated by Kaplan-Meier analysis and predictors were identified by the Cox regression model.

RESULTS

A total of 469 patients (median age, 71 years old) were included. The majority of them (86.6 %) were male. With a median time of 13.6 months, SR was detected in 129 (27.5 %) patients after the index EVAR. Compared with never smokers, current smokers were more likely to experience SR (adjusted HR 2.630, p < .001), while former smokers did not show any significant difference. Multivariate Cox regression also showed that maximal aneurysm diameter (adjusted HR 1.012, p = 0.035) and female (adjusted HR 1.675, p = .045) were independent predictors of SR. A total of 51 (10.9 %) patients had MaSR at a median time of 15.4 months after EVAR. In multivariate analysis, maximal aneurysm diameter and Zenith stent graft were independently associated with MaSR.

CONCLUSION

In Chinese population, the incidence of SR and MaSR was 27.5 % and 10.9 % after EVAR, respectively. Maximal aneurysm diameter and female were independent predictors of SR. Compared with never smokers, it was more likely to have SR in current smokers.

Factors Influencing on the Aneurysm Sac Shrinkage after Endovascular Abdominal Aortic Aneurysm Repair by the Analysis of the Patients with the Aneurysm Sac Shrinkage and Expansion

Objectives: The aneurysmal sac shrinkage has been reported as the strong predictor of favorable long-term outcome after endovascular aneurysm repair (EVAR). We evaluated the effects of perioperative and intraoperative factors on the aneurysm sac shrinkage. Methods: EVAR was performed for 296 patients during August 2009-December 2021. Nine patients with type Ia, Ib, or III; 69 patients with the sac diameter change less than 5 mm; and five patients with sac re-expansion after shrunk more than 5 mm were excluded. Thus, patients with sac shrinkage 5 mm or more (79 patients, shrinkage group) and with sac expansion 5 mm or more (18 patients) were included in this study. Antifibrinolytic therapy with tranexamic acid (TXA) 1500 mg/day for 6 months after EVAR was introduced in March 2013 and patent aortic side branches were coil embolized during EVAR since July 2015. Patients' background and patent aortic side branches at the end of EVAR were evaluated. Results: Univariate analysis for comparison between patients with sac shrinkage and sac expansion revealed that males (82.3% vs. 55.6%, p = 0.021), without antiplatelet therapy (40.5% vs. 66.7%, p = 0.044) and TXA (79.8% vs. 38.9%, p <0.001), were significantly associated with sac shrinkage. By multivariate analysis, the odds ratio of sac shrinkage was 11.7 for males, 0.1 for the patients on antiplatelet therapy, and 6.5 for the patient who received TXA. The patients with patent inferior mesenteric artery (IMA) were less in the shrinkage group (20.3% vs. 77.8%, p <0.001) and with two or less patent lumbar arteries (LAs) were more in the shrinkage group (82.3% vs. 33.3%, p < 0.001). The odd ratio of sac shrinkage was 7.8 for occluded IMA and 3.9 for two or less patent LAs. Conclusion: The possibility of sac shrinkage would be high for the patient with occluded IMA and two or less patent LA at the end of EVAR, and that patient received TXA after EVAR. (This is a translation of Jpn J Vasc Surg 2022; 31: 291-297.).

Impact of patient demographics and intraoperative characteristics on abdominal aortic aneurysm sac following endovascular repair

BACKGROUND

Endovascular aortic repair (EVAR) has become the preferred treatment for abdominal aortic aneurysm (AAA). Its main aim is to seal the perfusion of the aneurysmal sac and, thus, induce sac regression and subsequent aortic remodelling. Aneurysmal sac regression has been linked to the short- and long-term clinical outcomes post-EVAR. It has also been shown to be influenced by endograft device choice, with several of these available commercially. This review summarises and discusses current evidence on the influence of pre- and intraoperative factors on sac regression. Additionally, this review aims to highlight the device-specific variations in sac regression to provide an overall holistic approach to treating AAAs with EVAR.

METHODS

A comprehensive literature search was conducted using multiple electronic databases to identify and extract relevant data.

RESULTS

Female sex, >70 mm original sac diameters, higher pre-procedural fibrinogen levels, smoking and low intra-aneurysmal pressure were found to positively impact sac regression. Whereas renal impairment, ischemic heart disease, high intra-aneurysmal pressure and aneurysm neck thrombus negatively influenced sac regression. Patent lumbar arteries, age, statins and hypercholesterolaemia displayed conflicting evidence regarding sac regression. Regarding the EVAR endografts compared, newer generation devices such as the Anaconda mainly showed the most optimal results.

CONCLUSION

Sac regression following EVAR in AAA is an important prognostic factor for morbidity and mortality. Nevertheless, several pre- and intraoperative factors can have an influence on sac regression. Therefore, it is necessary to take them into account when assessing AAA patients for EVAR to optimise outcomes. The choice of EVAR stent-graft can also affect sac regression, with evidence suggesting that the Fenestrated Anaconda is associated with the most favourable results.

Thrombosis in the pathogenesis of abdominal aortic aneurysm

Background

Abdominal aortic aneurysms (AAAs) are a relatively common vascular pathology of the elderly with high morbidity potential. Irreversible degeneration of the aortic wall leads to lethal rupture if left untreated. Nearly all AAAs contain intraluminal thrombus (ILT) to a varying degree, yet the mechanisms explaining how thrombosis is disturbed in AAA are relatively unknown. This review examined the thrombotic complications associated with AAA, the impact of thrombosis on AAA surgical outcomes and AAA pathogenesis, and the use of antithrombotic therapy in the management of this disease.

Methods

A literature search of the PubMed database was conducted using relevant keywords related to thrombosis and AAAs.

Results

Thrombotic complications are relatively infrequent in AAA yet carry significant morbidity risks. The ILT can impact endovascular aneurysm repair by limiting anatomic suitability and influence the risk of endoleaks. Many of the pathologic mechanisms involved in AAA development, including hemodynamics, inflammation, oxidative stress, and aortic wall remodeling, contain pathways that interact with thrombosis. Conversely, the ILT can also be a source of biochemical stress and exacerbate these aneurysmal processes. In animal AAA models, antithrombotic therapies have shown favorable results in preventing and stabilizing AAA. Antiplatelet agents may be beneficial for reducing risks of major adverse cardiovascular events in AAA patients; however, neither antiplatelet nor anticoagulation is currently used solely for the management of AAA.

Conclusions

Thrombosis and ILT may have detrimental effects on AAA growth, rupture risk, and patient outcomes, yet there is limited understanding of the pathologic thrombotic mechanisms in aneurysmal disease at the molecular level. Preventing ILT using platelet and coagulation inhibitors may be a reasonable theoretical target for aneurysm progression and stability; however, the practical benefits of current antithrombotic therapies in AAA are unclear. Further research is needed to demonstrate the extent to which thrombosis impacts AAA pathogenesis and to develop novel pharmacologic strategies for the medical management of this disease.

A stable aneurysm sac after endovascular aneurysm repair as a predictor for mortality, an in-depth analysis

OBJECTIVES

The aim of this study was to compare the long-term survival in patients with a stable aneurysmal sac and those with aneurysmal sac regression after endovascular aneurysm repair (EVAR) and to identify independent risk factors for aneurysmal sac regression and mortality after EVAR.

METHODS

We reviewed all patients who underwent EVAR between 2005 and 2018 with a computed tomography angiography available at 1-year follow-up. Aneurysm sac regression was defined as a diameter decrease of more than 10%. We used a multivariable regression to identify independent risk factors for sac regression. Kaplan-Meier analysis and Cox regression were done to test differences in 5-year mortality between a stable sac and sac regression.

RESULTS

The inclusion criteria were met by 325 patients, 185 in the sac regression group and 140 in the stable sac group. Multivariable logistic regression analysis showed that treatment for a ruptured aneurysm was an independent risk factor for aneurysmal sac regression (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.07-0.96). Age (HR, 1.05; 95% CI, 1.01-1.09), ischemic heart disease (HR, 1.94; 95% CI, 1.13-3.31), neck thrombus (HR, 2.72; 95% CI, 1.07-6.95), and a type II endoleak (HR, 19.21; 95% CI, 7.32-50.40) were independent risk factors for a stable aneurysm sac diameter. Multivariable Cox regression showed a significantly increased risk of mortality for patients with a stable aneurysm sac after EVAR (odds ratio, 2.25; 95% CI, 1.36-3.72). There was no significant difference in cause of death between the two groups.

CONCLUSION

A stable aneurysm sac after EVAR is associated with increased mortality. Age, ischemic heart disease, neck thrombus, and a type II endoleak are independent risk factors for a stable sac. However, a well-founded explanation for this finding is still lacking. Future research should be focussed on aggressive treatment of type II endoleaks and inflammatory processes as potential pathophysiological mechanisms.

The Effect of Transfusion of Two Units of Fresh Frozen Plasma on the Perioperative Fibrinogen Levels and the Outcome of Patients Undergoing Elective Endovascular Repair for Abdominal Aortic Aneurysm

BACKGROUND

We aimed to investigate whether the transfusion of 2 units of fresh frozen plasma (FFP) immediately post aneurysm exclusion has any effect on the perioperative fibrinogen levels and the outcome of patients undergoing elective endovascular repair (EVAR) of abdominal aortic aneurysm (AAA).

METHODS

Consecutive infrarenal AAA patients undergoing elective EVAR with the bifurcated Endurant-II stent-graft (Medtronic) were recruited from 2 vascular units. The first unit has a routine policy of administering 2 units of FFP immediately upon aneurysm exclusion (FFP group), whereas the second unit has no such policy (control group). Serum fibrinogen levels were measured on admission and 24 hr post-EVAR and the perioperative change in fibrinogen (Δfib) was calculated (24-hr postoperative minus preoperative fibrinogen). The 2 groups were compared with regards to the perioperative fibrinogen levels (preoperative, 24-hr postoperative, and Δfib) and the outcome (endoleaks, reinterventions, major adverse cardiovascular events, death) during follow up.

RESULTS

A total of 70 patients (41 in the FFP group, 29 controls) were examined. There were 68 men, the mean age was 70 ± 7 years and the maximum AAA diameter was 63.3 ± 13.8 mm. During the follow up (34 ± 19 months), a total of 6 endoleaks were recorded (2 type Ia, 2 type Ib and 1 type II). Mean preoperative fibrinogen, 24-hr postoperative fibrinogen and Δfib was 391.1 ± 92.8 mg/dL, 367.7 ± 97.8 mg/dL and -23.5 ± 51.02 mg/dL, respectively. There was a trend for the fibrinogen to fall 24 hr postprocedure, but this was not statistically significant (P = 0.07). There was a weak negative association between Δfib and endoleaks (P = 0.007, r = -0.29). Compared to controls, the FFP group had a higher 24-hr postoperative fibrinogen (401.8 ± 112.9 mg/dL vs. 319.3 ± 34.9 mg/dL, P < 0.0001) and a lower Δfib (-3.00 ± 56.01 mg/dL vs. -52.48 ± 21.15 mg/dL, P < 0.0001). No significant difference was observed between the 2 groups with regards to endoleaks, reinterventions, major adverse cardiovascular events, or deaths.

CONCLUSIONS

Transfusion of 2 units of FFP postaneurysm exclusion prevents a significant drop in plasma fibrinogen 24 hr post-EVAR, but the impact on clinical outcome has yet to be defined.

Aneurysms and dissections - What is new in the literature of 2019/2020 - a European Society of Vascular Medicine annual review

More than 6,000 publications were found in PubMed concerning aneurysms and dissections, including those Epub ahead of print in 2019, printed in 2020. Among those publications 327 were selected and considered of particular interest.