Apolipoprotein E (ApoE) Rescues the Contractile Smooth Muscle Cell Phenotype in Popliteal Artery Aneurysm Disease

Bypass Patency and Amputation-Free Survival after Popliteal Aneurysm Exclusion Significantly Depends on Patient Age and Medical Complications: A Detailed Dual-Center Analysis of 395 Consecutive Elective and Emergency Procedures

Background/Objectives: A popliteal artery aneurysm (PAA) is traditionally treated by an open PAA repair (OPAR) with a popliteo-popliteal venous graft interposition. Although excellent outcomes have been reported in elective cases, the results are much worse in cases of emergency presentation or with the necessity of adjunct procedures. This study aimed to identify the risk factors that might decrease amputation-free survival (efficacy endpoint) and lower graft patency (technical endpoint). Patients and Methods: A dual-center retrospective analysis was performed from 2000 to 2021 covering all consecutive PAA repairs stratified for elective vs. emergency repair, considering the patient (i.e., age and comorbidities), PAA (i.e., diameter and tibial runoff vessels), and procedural characteristics (i.e., procedure time, material, and bypass configuration). Descriptive, univariate, and multivariate statistics were used. Results: In 316 patients (69.8 ± 10.5 years), 395 PAAs (mean diameter 31.9 ± 12.9 mm) were operated, 67 as an emergency procedure (6× rupture; 93.8% severe acute limb ischemia). The majority had OPAR (366 procedures). Emergency patients had worse pre- and postoperative tibial runoff, longer procedure times, and more complex reconstructions harboring a variety of adjunct procedures as well as more medical and surgical complications (all p < 0.001). Overall, the in-hospital major amputation rate and mortality rate were 3.6% and 0.8%, respectively. The median follow-up was 49 months. Five-year primary and secondary patency rates were 80% and 94.7%. Patency for venous grafts outperformed alloplastic and composite reconstructions (p < 0.001), but prolonged the average procedure time by 51.4 (24.3-78.6) min (p < 0.001). Amputation-free survival was significantly better after elective procedures (p < 0.001), but only during the early (in-hospital) phase. An increase in patient age and any medical complications were significant negative predictors, regardless of the aneurysm size. Conclusions: A popliteo-popliteal vein interposition remains the gold standard for treatment despite a probably longer procedure time for both elective and emergency PAA repairs. To determine the most effective treatment strategies for older and probably frailer patients, factors such as the aneurysm size and the patient's overall condition should be considered.

Current understanding of macrophages in intracranial aneurysm: relevant etiological manifestations, signaling modulation and therapeutic strategies

Macrophages activation and inflammatory response play crucial roles in intracranial aneurysm (IA) formation and progression. The outcome of ruptured IA is considerably poor, and the mechanisms that trigger IA progression and rupture remain to be clarified, thereby developing effective therapy to prevent subarachnoid hemorrhage (SAH) become difficult. Recently, climbing evidences have been expanding our understanding of the macrophages relevant IA pathogenesis, such as immune cells population, inflammatory activation, intra-/inter-cellular signaling transductions and drug administration responses. Crosstalk between macrophages disorder, inflammation and cellular signaling transduction aggravates the devastating consequences of IA. Illustrating the pros and cons mechanisms of macrophages in IA progression are expected to achieve more efficient treatment interventions. In this review, we summarized the current advanced knowledge of macrophages activation, infiltration, polarization and inflammatory responses in IA occurrence and development, as well as the most relevant NF-κB, signal transducer and activator of transcription 1 (STAT1) and Toll-Like Receptor 4 (TLR4) regulatory signaling modulation. The understanding of macrophages regulatory mechanisms is important for IA patients' clinical outcomes. Gaining insight into the macrophages regulation potentially contributes to more precise IA interventions and will also greatly facilitate the development of novel medical therapy.