Incidence of Post-Implantation Syndrome with Different Endovascular Aortic Aneurysm Repair Modalities and Devices and Related Etiopathogenetic Implications

Stent-Induced Inflammation: A Comparative Cross-Sectional Study of Post-Implantation Syndrome in Venous and Arterial Procedures

Background: Postimplantation syndrome (PIS) is a known inflammatory response following endovascular stent placement, yet comparative data between venous and arterial stenting remains limited. This study seeks to evaluate the incidence, characteristics, and clinical implications of PIS across these two distinct vascular territories. Methods: We retrospectively analyzed 191 patients who underwent either venous (n = 36) or arterial (n = 155) stent placement. Data collection encompassed demographic profiles, perioperative laboratory findings, and clinical outcomes. The primary endpoint was the incidence of PIS, defined as the presence of fever (≥38 °C), leukocytosis, and elevated C-reactive protein (CRP) within 30 days postprocedure. Secondary outcomes included length of hospital and ICU stay, incidence of endoleaks, reintervention rates, and 30-day mortality. Comparative statistical analyses were conducted to assess differences between the venous and arterial stent groups. Results: PIS was observed more frequently in arterial stent patients, as evidenced by significantly elevated postoperative white blood cell counts at 24 and 48 h (p = 0.046 and p = 0.014, respectively), along with borderline CRP increases (p = 0.052). Fever occurrence peaked at 72 and 96 h postprocedure, predominantly in the arterial cohort. Furthermore, patients with arterial stents had significantly longer hospital stays (5.59 ± 0.46 days vs. 3.42 ± 0.36 days; p = 0.0018) and a higher rate of 30-day endoleaks (7.1% vs. 0%; p = 0.005). Despite similar mortality and major adverse cardiac event (MACE) rates between groups, arterial stent patients exhibited a greater need for reintervention. While PIS was less common among venous stent recipients, its potential impact on postoperative recovery warrants careful monitoring. Conclusions: Arterial stenting is associated with a higher incidence of PIS and a more pronounced systemic inflammatory response, contributing to longer hospitalization and increased postoperative complications. Although venous stent patients experience PIS less frequently, its occurrence should not be overlooked, as it may influence overall recovery and clinical outcomes. Recognition and management of PIS in both venous and arterial stent patients are critical to improving patient care and optimizing procedural success.

Fever Management after TEVAR in Patients with Aortic Dissection

BACKGROUND

Post-implantation syndrome (PIS) is characterised as a noninfectious continuous fever and a concomitant rise in inflammatory markers shortly after thoracic endovascular aortic repair (TEVAR). This current study aims to analyse the risk factors of PIS, postoperative major adverse cardiac events (MACE), and overall survival as well as the correlation between new-onset mural thrombus and the risk of developing PIS after TEVAR in patients with type B aortic dissection (TBAD). Patients were included who had a B dissection, both acute and chronic forms. In the acute form, both acutely complicated and uncomplicated patients were included in the study. A main point of our investigation is the postoperative fever management of PIS patients.

METHODS

A total of 90 patients with type B dissection underwent TEVAR in the University Hospital of Muenster between 2016 and 2020. The occurrence of PIS was defined as the presence of fever (> 38°C lasting longer than 24 hours in hospital) and leucocytosis (white blood cell count > 12000/µL). Patients with other possible reasons for fever and/or leucocytosis, such as a urinary tract infection (UTI), pneumonia, or sepsis, were excluded beforehand. Besides demographic and operation-related data, inflammatory markers and therapeutic measures were evaluated before and 5 days postoperatively. Computed tomography scans were examined to calculate the volume of preexistent and new-onset mural thrombus after TEVAR.

RESULTS

Of 90 patients, 40 patients were excluded because of recent infection or bypass surgery. Of the 50 patients included in the study, 10 patients developed post-implantation syndrome. Younger patients significantly more often developed PIS after TEVAR (52.2 ± 11.6 vs. 61.5 ± 13.6, p = 0.045). New-onset thrombus after TEVAR was significantly higher in PIS patients (61 cm³ vs. 12 cm³, p < 0.001) and PIS patients often received more medical examinations (investigation of X-ray, U status, and blood cultures). There was no significant difference in overall survival for 40 months and in the incidence of MACE.

CONCLUSIONS

PIS may be related to an increased rate of new-onset thrombus. A more robust conclusion is not justified according to our study. There is no difference in overall survival.

Outcomes of post-implantation syndrome after endovascular repair for Stanford type B aortic dissection

OBJECTIVE

The aim of this study was to investigate the correlation between post-implantation syndrome (PIS) and long-term prognosis in patients with Stanford type B aortic dissection (TBAD) undergoing thoracic endovascular aortic repair (TEVAR).

METHODS

This retrospective study included 547 consecutive patients diagnosed with TBAD who underwent TEVAR at our institution between January 2014 and December 2019. Patients were categorized into two groups: the PIS group (patients with post-TEVAR PIS) and the non-PIS group (patients without post-TEVAR PIS). In-hospital and follow-up data were analyzed.

RESULTS

The incidence of PIS was 28.9% (158/547 patients). No baseline differences were observed between the PIS (n = 158) and the non-PIS (n = 389) groups. The proportion of emergency surgery in the PIS group was higher than that in the non-PIS group (44.9% vs 26.0%; P < .001), the operation time was longer (median, 65.0; interquartile range [IQR], 56.0-75.0 minutes vs 56.0; IQR, 45.0-66.0 minutes; P < .001), the volume of contrast medium used (median, 65.0; IQR, 56.0-75.0 mL vs 56.0; IQR, 45.0-66.0 mL; P < .001), and the average number of trunk stents (1.85 ± 0.4 vs 1.34 ± 0.5 pieces; P < .001) and branch stents (0.7 ± 0.7 vs 0.2 ± 0.5 pieces; P < .001) used were more in the PIS group than in the non-PIS group. The incidence of supra-aortic branch procedures was higher in the PIS group than in the non-PIS group. There was no significant difference in device-related complications (DRCs) or 30-day mortality between the two groups (2.5% vs 4.4%; P = .442 and 1.3% vs 1.3%; P = .688, respectively). Univariate and multivariable logistic regression analysis showed that emergency surgery, number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL were risk factors for PIS, and the odds ratios of emergency operation, number of trunk stents >1 piece, operation time >58.5 minutes, and contrast medium volume >75 mL were 2.526 (95% confidence interval [CI], 1.530-4.173), 4.651 (95% CI, 2.838-7.624), 3.577 (95% CI, 2.201-5.815), and 7.356 (95% CI, 4.111-13.160), respectively. Follow-up was completed in 98.5% (532/540) of the patients, with a median follow-up of 67 months (IQR, 50-86 months). There was no significant difference in survival between the PIS and non-PIS groups (12.4% vs 10.3%; P = .476) during follow-up. The incidences of DRCs (7.8% vs 11.6%; P = .200) and aortic false lumen thrombosis (75.8% vs 79.2%; P = .399) were comparable between the PIS and non-PIS groups. Univariate logistic regression analysis showed that PIS had no effect on long-term follow-up mortality, DRCs, entry flow, or aortic false lumen thrombosis rate.

CONCLUSIONS

PIS is relatively common after TEVAR and emergency surgery; number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL are of high predictive value for the assessment of PIS after TEVAR. However, PIS had little effect on early and late postoperative mortality or DRCs.

Systematic review of risk factors and outcomes of post-implantation syndrome following endovascular aortic repair

OBJECTIVE

Post implantation syndrome (PIS) is an early systemic inflammatory response following endovascular aortic repair (EVAR). The response is variable in patients and the clinical significance of PIS upon outcomes is unknown. This study aims to evaluate the incidence, risk factors, and prognostic implication of PIS.

METHODS

Systematic literature review and analysis was performed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) and Cochrane guidelines of PubMed, Scopus, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials. Eligible English-language studies regarding PIS after infrarenal EVAR were included, after removing duplicates.

RESULTS

After screening, 31 studies were included. A total of 2847 patients were reviewed, with mean age of 70.7 years, of which 2012 (90.4%) were male, with a pooled mean follow-up of 26.1 months. PIS was reported in 25.3% of cases, with mean aneurysm diameter of 56.4 cm. Polytetrafluoroethylene (PTFE) grafts were utilized in 794 patients (27.9%) with polyester in 1839 (64.6%). White blood cell count, C-reactive protein, interleukin (IL)-6, IL-8, and IL-10 levels were all significantly elevated postoperatively. Thirty-day outcomes included type I endoleak rate of 0.8%, type II endoleak rate of 1.7%, reintervention rate of 0.35%, and mortality rate of 0.25%. Subgroup pooled analysis of patients with PIS (n = 309) vs No-PIS (n = 691) revealed that polyester (n = 642), rather than PTFE (n = 234) grafts, were associated with a higher rate of PIS (94.8% vs 3.7%; P = .0001), White blood cell count was higher in the PIS group both preoperatively (7.61 vs 6.76 × 109/L; P = .04) and postoperatively (15.0 vs 9.8 × 109/L; P = .0007) and IL-6 levels were higher in the PIS group postoperatively (98.6 vs 25.2 pg/mL; P = .02). Aneurysm diameter and amount of chronic or new thrombus within the aneurysm sac was not identified as a risk factor for PIS. Pooled outcomes of patients with PIS vs No-PIS demonstrated a significantly higher rate of 30-day mortality (0.6% vs 0%; P = .03) and major adverse cardiac events (5.8% vs 0.43%; P < .0001) without any differences seen in reintervention or 30-day type I or type II endoleaks.

CONCLUSIONS

This systematic review suggests that polyester grafts are strongly associated with PIS compared with PTFE. Interestingly, this report is suggestive of an association between 30-day mortality and major adverse cardiac events and PIS. Given these clinical sequelae, consideration for use of PTFE over polyester grafts to reduce the incidence of PIS may be a simple step to improve overall outcome. Further, exploration of the relationship between inflammatory mediators associated with PIS and mortality and cardiac complications may engender deeper understanding of risks, leading to eventual mitigation of harm for patients experiencing PIS.

Impact of the underlying aortic pathology on postimplantation syndrome after endovascular thoracic aortic repair

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) is the treatment option of choice for almost all pathologies of the descending thoracic aorta. The aim of the present study was to determine the impact of aortic pathology on the occurrence of postimplantation syndrome (PIS) after TEVAR.

METHODS

Seventy-four patients undergoing TEVAR for aortic dissection (TAD, 25), aortic aneurysm (TAA, 26), and aortic rupture or perforated ulcer (TAR/PAU, 23) were included in this retrospective study. The clinical outcome measures were persistent inflammation at hospital discharge and in-hospital mortality.

RESULTS

PIS was assessed in 22.97% of all patients, predominantly in the TAD group (P=0.03). CRP increased after TEVAR (156.6±94.5, P<0.001; 108.1±57.7, P<0.01 and 117.8±70.4, P<0.05) vs. baseline (58.1±77.5, 31.94±52.1 and 31.9±52.1 mg/L, in TAD, TAA and TAR/PAU, respectively) and this increase was more accentuated in TAD group (P<0.05). Stent-length was similar in all groups (P=0.226) but correlated with postoperative CRP only in TAD (R=0.576, P=0.013). Fresh parietal thrombus correlated with CRP (R=0.4507, P=0.0005) and is (OR=1.0883, P=0.0001), together with the pathology of aortic dissection (OR=6.2268, P=0.0288), a predictor of PIS after TEVAR. Whereas mortality (5.4%) did not correlate with PIS (P=0.38) either with aortic pathology (P=0.225), hospital stay after TEVAR was significantly prolonged by PIS (P=0.03).

CONCLUSIONS

Aortic dissection is associated with more inflammation after TEVAR than aortic aneurysm, rupture or perforated ulcer, with the amount of fresh parietal thrombus playing the most significant role in the occurrence of PIS. Importantly, PIS prolongs hospital stay but not mortality after TEVAR.

Incidence and risk factors of post implantation syndrome after elective endovascular aortic aneurysm repair

BACKGROUND

Post implantation syndrome (PIS) represents an acute phase systemic inflammatory response following endovascular aortic aneurysm repair (EVAR). Our objective was to investigate the risk factors associated with the manifestation and severity of PIS with various available stent-grafts.

MATERIALS AND METHODS

We performed a retrospective analysis of prospectively collected data covering the period 2016 - 2020. 191 patients were included. Body temperature was recorded regularly and blood sample was obtained daily. The imaging protocol included computed tomography aortoiliac angiography before surgery and one month after. The volumes of pre-existing and new-onset mural thrombus were calculated in a semiautomated fashion. Five abdominal aortic stent-graft devices were used: Endurant™ ΙΙ, Anaconda™, Treo®, E-tegra® and AFX® 2. Subgroup analysis was performed between woven polyester and ePTFE lined devices.

RESULTS

The incidence of PIS was 21.5%. No significant differences were observed regarding demographics, risk factors, aneurysm anatomy or operative data. The amount of preexisting and new-onset mural thrombus were not related with PIS (p=0.117 and p=0.096). PIS incidence in the polyester subgroup was 24.2%, significantly higher compared to 8.3% in the ePTFE subgroup. In-subgroup analysis revealed that the use of Anaconda™ was associated with the higher frequency (61.1%, p=0.021). Multivariate logistic regression showed that polyester was the single factor significantly associated with PIS (hazard ratio=2.6, p=0.043), as opposed to the new onset thrombus (hazard ratio=1.29, p=0.101).

CONCLUSIONS

PIS is not uncommon and should be taken into consideration in patients presenting with fever after EVAR. The endograft's liner material seems to play the primordial role, with woven polyester to be attributed with significantly higher incidence.

Midterm outcomes of 455 patients receiving the AFX2 endovascular graft for the treatment of abdominal aortic aneurysm: A retrospective multi-center analysis

Since being introduced into clinical practice the AFX family of endografts has undergone labelling updates, design and manufacturing changes to address a Type III failure mode. The published literature on the performance of the current endograft-AFX2 -is limited to small series with limited follow up. The present study reports the largest series of patients implanted with AFX2 for the treatment of abdominal aortic aneurysms. The study was a retrospective, 5 center study of patients receiving an AFX2 endograft from January 2016 until Dec 2020. Electronic case report forms were provided to four of the centers, with one additional site providing relevant outcomes in an independent dataset. Relevant outcomes were reported via Kaplan-Meier analysis and included all-cause mortality, aneurysm-related mortality, post EVAR aortic rupture, open conversion, device related reinterventions and endoleaks. Among a cohort of 460 patients, 405 underwent elective repair of an AAA, 50 were treated for a ruptured AAA, and 5 were aorto-iliac occlusive disease cases. For the elective cohort (mean age 73.7y, 77% male, mean AAA diameter 5.4cm), the peri-operative mortality was 1.7%. Freedom from aneurysm-related mortality was 98.2% at 1,2,3 and 4 years post-operatively, there were no post-operative aortic ruptures, and 2 patients required open conversion. Freedom from Type Ia endoleaks was 99.4% at 1, 2, 3 and 4 years. Freedom from Type IIIa and Type IIIb endoleaks were 100% and 100% (year 1), 100% and 99.6% (year 2), 99.4% and 99.6% (year 3), 99.4% and 99.6% (year 4) respectively. Freedom from all device-related reintervention (including Type II endoleaks) at 4 y was 86.8%. The AFX2 endograft appears to perform to a satisfactory standard in terms of patient centric outcomes in mid-term follow up. The Type Ia and Type III endoleaks rates at 4y appear to be within acceptable limits. Further follow up studies are warranted.

Factors Associated With Noninfectious Fever After Endovascular Aortic Aneurysm Repair

PURPOSE

The post-endovascular abdominal aortic aneurysm repair (EVAR) inflammatory response, which is very often associated with fever, has been ascribed to a wide range of proinflammatory mediators and operative events. The aim of this study was to evaluate the impact of such factors in the development of fever of noninfectious origin after elective EVAR.

MATERIALS AND METHODS

A retrospective analysis of prospectively collected data of patients treated with standard elective EVAR between February 2017 and December 2020 was undertaken. The database included patients' demographics and comorbidities, as well as laboratory inflammatory markers (white blood cell count, neutrophils, and C-reactive protein [CRP]) and anatomical characteristics (sac diameter, inferior mesenteric artery [IMA] patency and diameter, number of patent lumbar arteries, internal iliac artery [IIA] patency or occlusion). Intraoperative details, such as type of stent graft material and IIA overstenting, were also analyzed. Patients with infectious postoperative complications or previously receiving systemic anti-inflammatory medication were excluded. Statistical analysis was performed by SPSS 22.0 for Windows software (IBM Corp, Armonk, New York).

RESULTS

From 332 patients treated with elective EVAR between 2017 and 2020, 268 patients (all men) were included in the analysis. The mean age was 72.1±7.5 years and the mean aneurysm diameter was 59.1±12.1 mm. Seventeen patients were excluded due to a known infection site. From the study cohort, 114 (42.5%) patients presented with fever. Multivariate regression analysis confirmed that the occlusion of IMA ≥5 mm (p<0.008) and higher CRP (p<0.001) were independent factors associated with postoperative fever. A subanalysis was performed only on patients with patent IMA before EVAR. In the multivariate regression analysis of this subgroup, IMA ≥5 mm (p=0.008), presence of dyslipidemia (p=0.037), and higher CRP (p<0.001) were related to fever.

CONCLUSION

Occlusion of an existing wide (≥5 mm) and patent IMA prior to EVAR may contribute to the development of post-EVAR pyrexia. The CRP is a reliable marker for post-EVAR fever. Further prospective studies are needed to corroborate these findings.

Polyester Stent Graft Devices and Higher Risk of Post-Implantation Syndrome after EVAR: Single-Center Analysis of 367 Patients

BACKGROUND

The post-implantation syndrome may occur shortly after endovascular aneurysm repair in patients treated for abdominal aortic aneurysm. Different types of biomaterials may provoke varying inflammatory responses in patients receiving different endografts. The purpose of this article is to evaluate the PIS after EVAR and the influence of different types of device fabric.

METHODS

All patients submitted to elective AAA endovascular repair at our institution from January 2014 to December 2019 were enrolled. The PIS was defined by a body temperature of >38°C and WBC >12'000/μl without any evidence of an infection during (48h) the observation period.

RESULTS

Three hundred and sixty-seven patients (89% males) were enrolled in this study and post-implantation syndrome occurred in 41 cases (11.2%). The incidence of PIS was significantly higher (P< 0.001) in patients treated with polyester stent grafts (39/201, 19,4%) compared to patients with PTFE stent grafts (2/166, 1,2%). CRP was related to the presence of PIS with a cut-off values of 109.31 mg/dL (P = 0.0052). The median in-hospital stay considering the polyester group was 6,2 days, while in the PTFE group it was 5,6 days (P = 0.04).

CONCLUSIONS

The postoperative inflammatory response after EVAR seems significantly higher by using polyester stent graft compared to PTFE devices. CRP could be a useful biomarker in defining PIS. Multi-center studies are necessary to confirm these data.