Long Term Outcomes of Post-Implantation Syndrome After Endovascular Aneurysm Repair

Post-implantation syndrome in patients undergoing thoracic and abdominal endovascular aortic repair: Comprehensive systematic review and meta-analysis

Post-implantation syndrome (PIS) can lead to prolonged hospitalization and major adverse cardiovascular events (MACE). This systematic review and meta-analysis investigated the clinical profile of PIS after abdominal (EVAR) and thoracic endovascular aortic repair (TEVAR). A comprehensive literature search identified 1463 studies, of which 16 (14 retrospective and 2 prospective) met the inclusion criteria. Data from these studies were aggregated using a random effects model to calculate pooled risk ratios and mean differences. The analysis included 2890 patients (males 84.7%, mean age 63.3 years ± 18.8) with 882 experiencing PIS. No significant differences were found in demographics, anthropometric measurements, risk factors, medical history, or chronic medical treatments between the two groups. Fever (above 38°C) was the most frequent clinical manifestation, observed in 75-100% of PIS cases. As expected, higher levels of post-procedural white blood cells (WBC) and platelets (PLT) were shown in PIS patients compared to non-PIS patients. Interestingly, pre-procedural WBC and PLT counts were significantly higher in the PIS group (p<0.001 and p<0.002 respectively). Patients with PIS were more likely to receive polyester graft (p=0.003), while those with polytetrafluoroethylene prostheses were less likely to develop PIS (p=0.04). The PIS group exhibited longer hospital stays compared to the non-PIS group (p<0.001). While most studies reported no evident PIS impact on outcomes, two studies reported higher rate of MACE. Larger prospective studies are needed to determine the optimal management strategies of patients at risk of PIS.

Clinicopathological analysis of enlarged abdominal aortic aneurysms after endovascular aneurysm repair and the relationship with occult IgG4-related vascular disease

PURPOSE

To evaluate the incidence of IgG4-related vascular disease (IgG4-VD) in aneurysm enlargement after endovascular aneurysm repair (EVAR).

METHODS

Of 1482 EVAR cases in which patients underwent initial treatment at our hospital, 33 patients who underwent open surgery for an enlarged aneurysm were retrospectively identified. Histopathological examination of the aneurysm wall specimens was performed and the relationship of the histopathological findings with IgG4-VD was investigated.

RESULTS

The median aneurysm diameter at EVAR was 53 mm (interquartile range [IQR] 50-55), and the aneurysm diameter at open surgery was 79 mm (IQR 75-88). Six patients (18%) were histopathologically diagnosed with IgG4-VD. Relative to the non-IgG4-VD cases, the patients with IgG4-VD had a higher incidence of coronary artery disease (83% vs. 30%, p = 0.015) and greater aneurysm wall thickness at the time of open surgery (2.4 mm vs. 1.6 mm, p < 0.001). Serum IgG4 levels were significantly higher in patients with IgG4-VD than in those without IgG4-VD (218 mg/L vs. 46 mg/L, p = 0.002).

CONCLUSIONS

IgG4-VD was found in 18% cases with enlarged aneurysms after EVAR. If aneurysm enlargement is observed after EVAR, measurement of the aneurysm wall thickness using preoperative CT angiography and the evaluation of serum IgG4 levels could be useful for diagnosing occult IgG4-VD.

Risk Factors and Perioperative Outcomes of Postimplantation Syndrome After Thoracic Endovascular Aortic Repair

OBJECTIVE

Postimplantation syndrome (PIS) is a systemic inflammatory response that occurs following abdominal endovascular aortic repair (EVAR) and thoracic EVAR (TEVAR). The main outcome was to individuate the incidence and risk factors of PIS after TEVAR. Its impact on the length of stay and clinical outcomes were secondary objectives.

MATERIALS AND METHODS

Three hundred sixty-nine consecutive TEVAR procedures performed between February 2010 and November 2022 were included in this retrospective cohort, observational, single-center study. Patients with proximal landing in zones 0 to 5 were enrolled. Data on comorbidities, previous aortic surgery and morphology, thoracic aorta coverage, stent-graft composition, intraoperative variables, and postoperative outcomes were collected. White blood cell (WBC) and C-reactive protein (CRP) serum levels were recorded preoperatively and 48 hours after TEVAR. PIS was defined as the concomitant presence of fever (tympanic temperature ≥38.0°C), CRP serum level >0.7 mg/dl and evidence of pleural effusion on postoperative chest radiograph.

RESULTS

PIS incidence in our cohort was 26.8%. PIS patients presented with a higher rate of hyperlipidemia (56.6% vs 44.8%, p = 0.045) than non-PIS patients. Stent-graft composition did not play a relevant role in eliciting PIS. PIS was a statistically significant factor in prolonging patients' stay (median 16.0 days vs 8.0 days, p < 0.001, PIS and non-PIS patients). Thoracic aortic coverage >150 mm (Odds Ratio (OR) 4.7, p = 0.004), coronary artery disease (OR 2.1, p = 0.028), and preoperative WBC count (OR 1.1, p = 0.047) were identified as risk factors for PIS, whereas previous aortic surgery (OR 0.5, p = 0.05) was highlighted as a protective factor. Thoracic aortic coverage was a significant risk factor for increased WBC and CRP levels (p < 0.001).

CONCLUSION

PIS incidence was 26.8% in our cohort. Thoracic aortic coverage, coronary artery disease, and preoperative WBC count were identified as risk factors for PIS after TEVAR, whereas previous aortic surgery was found to be a protective factor. PIS also appeared to have a significant impact on length of stay.Clinical ImpactThis study identified a significant occurrence of post-implantation syndrome (PIS) following TEVAR, affecting over 25% of patients and adversely affecting the duration of hospital stay. Stent graft material did not seem to influence the incidence of PIS. Thoracic aortic coverage, coronary artery disease, and preoperative white blood cell (WBC) count have been identified as risk factors, whereas previous aortic surgery has been found to serve as a protective factor, representing a novel finding in the literature. Further research is warranted to ascertain strategies for mitigating the incidence of PIS, considering the risk factors identified in both current and prior studies. In addition, it is necessary to evaluate the potential implementation of preoperative prophylactic therapy for PIS in patients undergoing TEVAR.

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.

Risk prediction and prognostic analysis of post-implantation syndrome after thoracic endovascular aortic repair

This study aimed to establish a predictive model for the risk of post-thoracic endovascular aortic repair (TEVAR) post-implantation syndrome (PIS) in type B aortic dissection (TBAD) patients, assisting clinical physicians in early risk stratification and decision management for high-risk PIS patients. This study retrospectively analyzed the clinical data of 547 consecutive TBAD patients who underwent TEVAR treatment at our hospital. Feature variables were selected through LASSO regression and logistic regression analysis to construct a nomogram predictive model, and the model's performance was evaluated. The optimal cutoff value for the PIS risk nomogram score was calculated through receiver operating characteristic (ROC) curve analysis, further dividing patients into high-risk group (HRG) and low-risk group (LRG), and comparing the short to midterm postoperative outcomes between the two groups. In the end, a total of 158 cases (28.9%) experienced PIS. Through LASSO regression analysis and multivariable logistic regression analysis, variables including age, emergency surgery, operative time, contrast medium volume, and number of main prosthesis stents were selected to construct the nomogram predictive model. The model achieved an area under the curve (AUC) of 0.86 in the training set and 0.82 in the test set. Results from calibration curve, decision curve analysis (DCA) and clinical impact curve (CIC) demonstrated that the predictive model exhibited good performance and clinical utility. Furthermore, after comparing the postoperative outcomes of HRG and LRG patients, we found that the incidence of postoperative PIS significantly increased in HRG patients. The duration of ICU stay and mechanical assistance time was prolonged, and the incidence of postoperative type II entry flow and acute kidney injury (AKI) was higher. The risk of aortic-related adverse events (ARAEs) and major adverse events (MAEs) at the first and twelfth months of follow-up also significantly increased. However, there was no significant difference in the mortality rate during hospitalization. This study established a nomogram model for predicting the risk of PIS in patients with TBAD undergoing TEVAR. It serves as a practical tool to assist clinicians in early risk stratification and decision-making management for patients.

Management of Systemic Inflammatory Response Syndrome After Cardiovascular Interventions. Diagnostic, Prognostic, and Therapeutic Implications

A substantial number of patients may experience systemic inflammatory response syndrome (SIRS) and related adverse events after transcatheter aortic valve implantation and endovascular aortic aneurysm repair. Although a clear etiology has not been established, endothelial disruption and tissue-ischemic response secondary to the foreign material may represent the trigger events. A latency period (0 to 48 hours) may occur between the initial injury and onset of symptoms mirroring an initial local response followed by a systemic response. Clinical presentation can be mild or severe depending on external triggers and characteristics of the patient. Diagnosis is challenging because it simulates an infection, but lack of response to antibiotics, negative cultures are supportive of SIRS. Increased in-hospital stay, readmissions, major cardiovascular events, and reduced durability of the device used are the main complications. Treatment includes non-steroidal anti-inflammatory drugs or corticosteroids. In conclusion, further studies are warranted to fully explore pathophysiologic mechanisms underpinning SIRS and the possibility of enhancing device material immune compatibility to reduce the inflammatory reaction of the host tissue.

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.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Impact of post-implantation syndrome on outcomes in acute type B aortic syndrome patients undergoing endovascular repair

Background: The aim of this study was to explore the impact of post-implantation syndrome (PIS) on prognosis outcomes in individuals with type B acute aortic syndrome (AAS) undergoing thoracic endovascular aortic repair (TEVAR). Patients and methods: Data from type B AAS individuals who underwent TEVAR from January 2014 to April 2021 were retrospectively reviewed. Study subjects were divided into PIS and non-PIS (nPIS) groups and postoperative clinical outcomes were analyzed. Results: Our study cohort of 74 individuals with type B AAS included 40 aortic dissection (AD), 30 intramural hematoma (IMH), 4 penetrating aortic ulcer (PAU). The incidence of PIS was 14.9%. No statistically significant differences were found in baseline characteristics. The left subclavian artery (LSCA) reconstruction was performed more frequently among the PIS group (45.5% vs 9.5%, p=.008). Major adverse events (MAE) tended to be more frequent in the PIS group, but the difference was not significant (27.3% vs 22.2%, p=.707). At 2-year follow-up, results were comparable between the two groups. Kaplan-Meier analysis showed that PIS was not associated with a higher incidence of mortality, endoleak, new-onset AD, or stroke. A baseline neutrophil-to-lymphocyte ratio (NLR) >10.3 was associated with greater incidence of MAE. In individuals with IMH, better aortic remodeling evaluated by lower total aortic diameter/true lumen diameter (TAD/TLD) was achieved in the nPIS group (1.23±0.10 vs 1.43±0.07, p<.001), and a TAD/TLD ratio >1.32 was associated with significantly more MAE. Cox multivariate regression analysis also showed that a postoperative TAD/TLD ratio >1.32 was an independent risk factor for MAE (OR, 11.36; 95% CI, 1.53-84.26; p=.017). Conclusions: PIS was associated with a trend toward a higher incidence of MAE after TEVAR. In individuals with IMH, a TAD/TLD ratio >1.32 was an independent predictor of postoperative MAE.

Prevalence of type II endoleak after elective endovascular aneurysm repair with polytetrafluoroethylene- or polyester-based endografts

OBJECTIVE

Type II endoleak is the most frequent complication after endovascular abdominal aneurysm repair. Polytetrafluoroethylene and polyester (PE) are the two most commonly used graft materials in endovascular aneurysm repair (EVAR) devices. Biological properties of the material might influence the appearance and persistence of type II endoleak (T2EL). Therefore, the aim of this study was to evaluate potential differences in the prevalence of T2EL after EVAR between polytetrafluoroethylene (PTFE) and PE endografts in patients electively treated for an infrarenal abdominal aortic aneurysm.

METHODS

A single-center, retrospective, observational study was conducted between January 2011 and January 2022. Preoperative, procedural, and follow-up data were derived from electronic health records. Imaging included computed tomography scans, and/or duplex ultrasound examination. The primary end point was the prevalence of T2EL diagnosed within 1 year after EVAR. Secondary end points included the prevalence of T2EL throughout follow-up, early (≤30 days) and late (>30 days) T2EL, the rate of T2EL disappearance during the follow-up period, the prevalence of type I and III endoleak, and T2EL-related reinterventions.

RESULTS

Follow-up was available for 394 patients, 245 in the PE and 149 in the PTFE group. The prevalence of T2EL diagnosed within 1 year after endovascular repair was 11.8% in the PE group and 21.5% in the PTFE group (P = .010). There was no significant difference in early (≤30 days) and late (>30 days) T2EL between groups (P = .270 and P = .311). There was no difference in the freedom from endoleak type II reinterventions between groups (P = .877).

CONCLUSIONS

The prevalence of T2EL after elective EVAR is significantly higher with the use of PTFE-based endografts compared with PE-based endografts. This difference is mostly based on T2EL diagnosed after 30 days of follow-up.

Post-Implantation Syndrome Incidence is Higher After Complex Endovascular Aortic Procedures Than After Standard Infrarenal Repair

OBJECTIVE

Post-implantation syndrome (PIS), characterised by malaise, fever, and increased inflammatory markers, is a common occurrence after endovascular aneurysm repair (EVAR), causing prolonged hospitalisation and increased cost. This study aimed to determine the incidence and short-term outcomes of PIS after fenestrated or branched procedures in aorto-iliac aneurysms compared with standard EVAR.

METHODS

A retrospective, comparative study from a tertiary academic institution was undertaken. All patients who underwent elective EVAR with polyester stent grafts from January 2015 to June 2021 were considered. Two groups were defined: standard EVAR (sEVAR) and complex EVAR (cEVAR). The latter included visceral fenestrated and branched or iliac branch and chimney stent grafts. The primary outcome was the incidence of PIS within three days of the index procedure. Secondary outcomes were short-term complications and risk factors for PIS. A multivariable model was constructed to correct for confounders.

RESULTS

Overall, 253 patients were included: 165 (65.2%) sEVAR and 88 (34.8%) cEVAR. Complex EVAR patients were younger, with larger aneurysms, had longer procedures, and were more likely to have intra-operative complications. The PIS incidence was 23.7% (n = 60), significantly higher in cEVAR (34.1% vs. 18.2%; p = .005) and increased with the complexity of the procedure (EVAR: 18.2% vs. EVAR + iliac branch device: 25.0% vs. fenestrated and branched EVAR: 36.2%; p = .030). On multivariable analysis, cEVAR (OR 2.833, 95% CI 1.295 - 6.198; p = .009) was associated with a significantly increased risk of PIS. No differences in short term outcomes according to PIS status were noted. Group sub-analysis for cEVAR patients did not reveal any statistically significantly different outcomes according to PIS occurrence.

CONCLUSION

In this cohort, cEVAR procedures were associated with a significantly increased risk of developing PIS compared with standard infrarenal repair. Post-implantation syndrome also appears to have a benign course with no major impact on peri-operative outcomes after cEVAR. Further research to confirm these findings is required.

Unveiling the Enigma of Post-implantation Syndrome Following Aortic Dissection Repair: A Case Report

Post-implantation syndrome (PIS) is a frequent complication after aortic dissection repair surgery, posing significant risks to patient recovery and survival. We present a case report of a 62-year-old male who underwent aortic dissection repair surgery and developed PIS. The patient exhibited symptoms of fever, pain, and inflammation at the surgery site, along with increased levels of inflammatory markers. He was managed with a combination of anti-inflammatory medications, pain management, and antibiotics, which gradually improved symptoms over weeks. Our case highlights the importance of recognizing the potential for PIS in patients undergoing aortic dissection repair surgery and employing timely interventions to manage this condition.