Deciphering Popliteal Artery Aneurysm Patient Diversity: Insights From a Cluster Analysis of the POPART Registry.

BACKGROUND: Popliteal artery aneurysms (PAAs) are the most common peripheral aneurysm. However, due to its rarity, the cumulative body of evidence regarding patient patterns, treatment strategies, and perioperative outcomes is limited. This analysis aims to investigate distinct phenotypical patient profiles and associated treatment and outcomes in patients with a PAA by performing an unsupervised clustering analysis of the POPART (Practice of Popliteal Artery Aneurysm Repair and Therapy) registry. METHODS AND RESULTS: A cluster analysis (using k-means clustering) was performed on data obtained from the multicenter POPART registry (42 centers from Germany and Luxembourg). Sensitivity analyses were conducted to explore validity and stability. Using 2 clusters, patients were primarily separated by the absence or presence of clinical symptoms. Within the cluster of symptomatic patients, the main difference between patients with acute limb ischemia presentation and nonemergency symptomatic patients was PAA diameter. When using 6 clusters, patients were primarily grouped by comorbidities, with patients with acute limb ischemia forming a separate cluster. Despite markedly different risk profiles, perioperative complication rates appeared to be positively associated with the proportion of emergency patients. However, clusters with a higher proportion of patients having any symptoms before treatment experienced a lower rate of perioperative complications. CONCLUSIONS: The conducted analyses revealed both an insight to the public health reality of PAA care as well as patients with PAA at elevated risk for adverse outcomes. This analysis suggests that the preoperative clinic is a far more crucial adjunct to the patient's preoperative risk assessment than the patient's epidemiological profile by itself.

Exploring the Effects of Local Air Pollution on Popliteal Artery Aneurysms.

Objectives: A growing body of evidence highlights the effects of air pollution on chronic and acute cardiovascular diseases, such as associations between PM10 and several cardiovascular events. However, evidence of the impact of fine air pollutants on the development and progression of peripheral arterial aneurysms is not available. Methods: Data were obtained from the multicenter PAA outcome registry POPART and the German Environment Agency. Means of the mean daily concentration of PM10, PM2.5, NO2, and O3 concentrations were calculated for 2, 10, and 3650 days prior to surgery for each patient. Additionally, weighted ten-year averages were analyzed. Correlation was assessed by calculating Pearson correlation coefficients, and regression analyses were conducted as multiple linear or multiple logistic regression, depending on the dependent variable. Results: For 1193 patients from the POPART registry, paired air pollution data were available. Most patients were male (95.6%) and received open surgical repair (89.9%). On a regional level, the arithmetic means of the daily means of PM10 between 2000 and 2022 were neither associated with average diameters nor runoff vessels. Negative correlations for mean PAA diameter and mean NO2, as well as a positive correlation with mean O3, were found; however, they were not statistically significant. On patient level, no evidence for an association of mean PM10 exposure over ten years prior to inclusion in the registry and PAA diameter or the number of runoff vessels was found. Weighted PM10, NO2, and O3 exposure over ten years also did not result in significant associations with aneurysm diameter or runoff vessels. Short-term air pollutant concentrations were not associated with symptomatic PAAs or with perioperative complications. Conclusions: We found no indication that long-term air pollutant concentrations are associated with PAA size or severity, neither on a regional nor individual level. Additionally, short-term air pollution showed no association with clinical presentation or treatment outcomes.

Sex disparities in popliteal artery aneurysms.

OBJECTIVE: Only 5% of patients with popliteal artery aneurysms (PAAs) are female. Evidence on PAA treatment and outcomes in women is therefore scarce. The POPART Registry provides one of Europe's largest data collections regarding PAA treatment. Data on clinical presentation, aneurysm morphology, and perioperative outcomes after open surgical PAA repair in women will be presented. METHODS: POPART is a multicenter, noninterventional registry for open and endovascular PAA repair, with 42 participating centers in Germany and Luxembourg. All patients aged >18 years who have been treated for PAA since 2010 are eligible for study inclusion. Data collection is based on an online electronic case report form. RESULTS: Of the 1236 PAAs, 58 (4.8%) were in women. There were no significant differences in age or cardiopulmonary comorbidities. However, female patients had a lower prevalence of contralateral PAAs and abdominal aortic aneurysms (P < .05). PAAs in women were more likely to be symptomatic before surgery (65.5% vs 49.4%; P = .017), with 19% of women presenting with acute limb ischemia (vs 11%; P = .067). Women had smaller aneurysm diameters than men (22.5 mm vs 27 mm; P = .004) and became symptomatic at smaller diameters (20 mm vs 26 mm; P = .002). Only 8.6% of women and 11.6% of men underwent endovascular aneurysm repair (P > .05); therefore, the perioperative outcome analysis focused on open surgical repair. In total, 23.5% of women and 16.9% of men developed perioperative complications (P > .05). There were no differences in major cardiovascular events (P > .05), but women showed a higher incidence of impaired wound healing (15.7% vs 7.2%; P = .05) and major amputation (5.9% vs 1.1%; P = .027). Female sex was significantly associated with the need for nonvascular reinterventions within 30 days after surgery (odds ratio: 2.48, 95% confidence interval: 1.26-4.88), whereas no significant differences in the odds for vascular reinterventions were observed (odds ratio: 1.98, 95% confidence interval: 0.68-5.77). In the multiple logistic regression model, female sex, symptomatic PAAs, poor quality of outflow vessels, and graft material other than vein graft were independently associated with perioperative reinterventions. CONCLUSIONS: Women have smaller PAAs, are more likely to be symptomatic before treatment, and are more often affected by nonvascular reinterventions in the perioperative course. As our understanding of aneurysmatic diseases in women continues to expand, sex-specific treatment strategies and screening options for women in well-selected cohorts with modified screening protocols should be continuously re-evaluated.

Prognostic benefits of early vascular surgical intervention in patients with major peripheral vascular complications following transcatheter aortic valve implantation.

OBJECTIVES: This study aimed to analyze the incidence, surgical management of major vascular complications, and outcomes in patients undergoing transfemoral (TF) transcatheter aortic valve replacement (TAVR) at our center after strict selection of the access route, carefully considering all known major predictors. METHODS: Data of 494 consecutive patients with pre-interventional multi-slice computed tomography (CT) of the aorta who had undergone TF TAVR from 2009 to 2019 were analyzed. RESULTS: In total, 23/494 (4.7%) patients had major vascular and access-related complications of peripheral vessels and/or infrarenal aorta. These included hematomas that met the Valve Academic Research Consortium 3-criteria of major vascular complications (7/494, 1.4%), arterial dissections (3/494, 0.6%), pseudoaneurysm (6/494, 1.2%), thrombus of the external iliac artery leading to acute limb ischemia (1/494, 0.2%), fistula (1/494, 0.2%), and perforation (5/494, 1.0%). In total, 17/23 (73.9%) major vascular complications required immediate endovascular and/or open surgery. In 16/17 (94%) cases, only 1 surgical procedure was performed. The long-term survival of patients with and without major vascular complications of the peripheral vessels was determined after 2 years. CONCLUSIONS: Early vascular surgery intervention reversed the mortality disadvantage in patients with major complications of the peripheral vessels after TAVR. This underscores the importance of immediate vascular surgery stand-by as an indispensable requirement.

Real-world data of popliteal artery aneurysm treatment: Analysis of the POPART registry.

OBJECTIVE: Popliteal artery aneurysm (PAA) is a rare disease with a prevalence of 0.1% to 1%. Within previous years, endovascular repair (ER) of PAAs has been performed more frequently despite the lack of high-level evidence compared with open surgical repair (OSR). In 2014, the POPART registry was initiated to validate the current treatment options for PAA repair. METHODS: POPART is a multinational multicenter registry of the peri- and postoperative outcomes of ER and OSR for PAAs. Data sets were recorded using the online survey tool SurveyMonkey (available at: https://www.surveymonkey.com/). Regular monitoring and plausibility checks of the data sets are performed to ensure reliability. The aim of the present study was to report the findings from the POPART registry, which includes data from 41 centers. RESULTS: From June 2014 to August 2019, 794 cases had been recorded in the POPART registry. OSR had been performed in 662 patients and ER in 106 patients; 23 patients had been treated conservatively. Of the 106 patients in the primary ER group, 4 had required conversion to OSR. The ER patients were significantly older (ER, median, 71 years; OSR, median, 67 years; P < .05). No other significant differences were present in the demographic data, comorbidities, or aneurysm morphology between the two groups. Of the 662 patients in the OSR group, 50.3% were symptomatic compared with 29.2% of the 106 patients in the ER group (P < .05). Emergency treatment because of acute ischemia, critical ischemia, or rupture was necessary for 149 patients (22.5%) in the OSR group and 11 patients (10.3%) in the ER group. The most frequent postoperative complications were impaired wound healing (OSR, n = 47 [7.1%]; ER, n = 3 [2.8%]; P > .05) and major bleeding (OSR, n = 26 [3.9%]; ER, n = 3 [2.8%]; P > .05). The in-hospital length of stay was significantly longer for the OSR group than for the ER group (median, 10 days; range, 3-65 days; vs median, 7 days; range, 1-73 days). The overall patency for the OSR and ER groups after 12 and 24 months was 83.2% and 44.7% (P < .005) and 74.2% and 29.1% (P < .005), respectively. The outcomes with a prosthetic graft vs an autologous vein were significantly poorer in the OSR group (primary patency, 71.4% vs 88.1% at 12 months). CONCLUSIONS: To evaluate new treatment techniques such as ER for PAAs, real-world data are of essential importance. The present analysis of the first results for the POPART registry shows good perioperative results for endovascular treatment of PAA in asymptomatic patients with good outflow vessels. The perioperative complication rate is low and the postoperative hospital stay is shorter than after OSR. However, the patency rates after 12 and 24 months are low in the ER group compared to patients treated with open repair. More follow-up data is required for further interpretation; the completion of the data sets in the registry is ongoing.

Graduated compression stockings in the prevention of postoperative pulmonary embolism. A propensity-matched retrospective case-control study of 24 273 patients.

INTRODUCTION: Recommendations for venous thromboembolism and deep venous thrombosis (DVT) prophylaxis using graduated compression stockings (GCS) is historically based and has been critically examined in current publications. Existing guidelines are inconclusive as to recommend the general use of GCS.Patients/Methods: 24 273 in-patients (general surgery and orthopedic patients) undergoing surgery between 2006 and 2016 were included in a retrospectively analysis from a single center. From January 2006 to January 2011 perioperative GCS was employed additionally to drug prophylaxis and from February 2011 to March 2016 patients received drug prophylaxis alone. According to german guidelines all patients received venous thromboembolism prophylaxis with weight-adapted LMWH. Risk stratification (low risk, moderate risk, high risk) was based on the guideline of the American College of Chest Physicians. Data analysis was performed before and after propensity matching (PM). The defined primary endpoint was the incidence of symptomatic or fatal pulmonary embolism (PE). A secondary endpoint was the incidence of deep venous thromboembolism (DVT). RESULTS: After risk stratification (low risk n = 16 483; moderate risk n = 4464; high risk n = 3326) a total of 24 273 patient were analyzed. Before to PM the relative risk for the occurrence of a PE or DVT was not increased by abstaining from GCS. After PM two groups of 11 312 patients each, one with and one without GCS application, were formed. When comparing the two groups, the relative risk (RR) for the occurrence of a pulmonary embolism was: Low Risk 0.99 [CI95% 0.998-1.000]; Moderate Risk 0.999 [CI95% 0.95-1.003]; High Risk 0.996 [CI95% 0.992-1.000] (p > 0.05). The incidence of PE in the total group LMWH alone was 0.1% (n = 16). In the total group using LMWH + GCS, the incidence was 0.3% (n = 29). RR after PM was 0.999 [CI95% 0.998-1.00]. CONCLUSION: In comparison to prior studies with only small numbers of patients our trial shows in a large group of patients with moderate and high risk developing VTE we can support the view that abstaining from GCS-use does not increase the incidence of symptomatic or fatal PE and symptomatic DVT.

Report of a Quality Improvement Program for Reducing Postoperative Complications by Using a Surgical Risk Calculator in a Cohort of General Surgery Patients.

PURPOSE: The study investigates whether postoperative complications in elective surgery can be reduced by using a risk calculator via raising the awareness of the surgeon in a preoperative briefing. Postoperative complications like wound infections or pneumonia result in a high burden for healthcare systems. Multiple quality improvement programs address this problem like the ACS NSQIP Surgical Risk Calculator® (SRC). METHODS: To determine whether the preoperative usage of the SRC could reduce inpatient postoperative complications, two groups of 832 patients each were compared using propensity score matching. The SRC was employed retrospectively in the period 2012/2013 in one group ("Retro") and prospectively in the other group ("Prosp") in the period 2014/2015. Actual inpatient postoperative complications were classified by SRC complication categories and compared with the Clavien-Dindo complication classification system (Dindo et al. in Ann Surg 240:205-213, 2004). RESULTS: Comparing SRC "serious complication" and SRC "any complication," a nonsignificant increase in the "Prosp"-group was apparent (serious complication: 6.6% vs. 8.5%, p = 0.164; any complication: 8.5% vs. 9.7%, p = 0.444). CONCLUSION: Use of the SRC neither reduces inpatient postoperative complications nor the severity of complications. The calculations of the SRC rely on a 30-day postoperative follow-up. Poor sensitivity and medium specificity of the SRC showed that the SRC could not make accurate predictions in a short follow-up time averaging 6 days. Alternatively, since the observed complication rate was low in our study, in an environment of already highly implemented risk management tools, reductions in complications are not easily achieved.

EPLIN-α and -ß Isoforms Modulate Endothelial Cell Dynamics through a Spatiotemporally Differentiated Interaction with Actin.

Actin-binding proteins are essential for linear and branched actin filament dynamics that control shape change, cell migration, and cell junction remodeling in vascular endothelium (endothelial cells [ECs]). The epithelial protein lost in neoplasm (EPLIN) is an actin-binding protein, expressed as EPLIN-α and EPLIN-ß by alternative promoters; however, the isoform-specific functions are not yet understood. Aortic compared to cava vein ECs and shear stress-exposed cultured ECs express increased EPLIN-ß levels that stabilize stress fibers. In contrast, EPLIN-α expression is increased in growing and migrating ECs, is targeted to membrane protrusions, and terminates their growth via interaction with the Arp2/3 complex. The data indicate that EPLIN-α controls protrusion dynamics while EPLIN-ß has an actin filament stabilizing role, which is consistent with FRAP analyses demonstrating a lower EPLIN-ß turnover rate compared to EPLIN-α. Together, EPLIN isoforms differentially control actin dynamics in ECs, essential in shear stress responses, cell migration, and barrier function.

Reversible biliary occlusion in a small animal model: first description of a new technique.

BACKGROUND: Experimental models with reversible biliary occlusion resulted in a high mortality of the animals, up to 20-60% according to the literature. Our aim was to assess a safe and valid technique for reversible biliary occlusion with a low mortality. METHODS: We randomized 30 rats into two groups: with bile duct occlusion (BDO, n=18) and with sham manipulation of the extrahepatic bile duct (control, n=12). We used a removable vascular clip for temporary occlusion of the extrahepatic bile duct. The clip was removed on postoperative day (POD) 2. On POD 2, 3, and 5, we measured the hepatocellular injury and metabolic function markers in serum. Activation of mononuclear cells (HIS36) and expression of regeneration markers [cytokeratin 19, hepatic growth factor (HGF)-α, and HGF-ß] were determined by immunohistochemistry. RESULTS: The survival rate was 96.67% (1/30); one animal died. The mortality in the BDO group was 6% (1/18) and that in the control group was 0% (0/12). BDO resulted in a sharp increase of hepatocellular injury and cholestatic parameters on POD 2 with a rapid decline till POD 3. Significantly strongest activation of Kupffer cells and expression of proliferation markers were found until POD 5 after BDO. CONCLUSION: The clip technique is a safe, cheap, and valid method for reversible biliary occlusion with an extremely low mortality.

Staged treatment of mega aortic syndrome using the frozen elephant trunk and hybrid thoracoabdominal repair.

OBJECTIVE: We report our experience with a staged hybrid approach for the treatment of extended aortic disease, also known as "mega aortic syndrome." METHODS: A total of 15 patients (10 male, 5 female) underwent staged repair of the thoracoabdominal aorta, consisting of 3 separate stages (repair of ascending aorta and aortic arch using the frozen elephant trunk technique and hybrid thoracoabdominal repair with debranching of the renovisceral branches and stent graft implantation). RESULTS: The procedure was completed in 14 patients. After the first stage (repair of ascending aorta and aortic arch), no mortality or spinal cord ischemia occurred. One patient required temporary dialysis. After the thoracoabdominal repair, permanent paraplegia developed in 1 patient. One patient died intraoperatively after aneurysm rupture. The in-hospital mortality for the complete repair reached 6.7%. None of the surviving patients required permanent dialysis. Interval aortic events consisted of 1 contained rupture. CONCLUSIONS: The concept of a staged hybrid repair of the mega aortic syndrome is technically feasible. The frozen elephant trunk technique represents an attractive treatment option, offering an adequate landing zone for later thoracoabdominal repair in patients with extended aortic disease. For completion of the repair, a staged hybrid approach with renovisceral debranching and aneurysm exclusion using off-the-shelf stent grafts shows promising results with low surgical morbidity and mortality.

Chronic mesenteric ischemia: time to remember open revascularization.

Chronic mesenteric ischemia is caused by stenosis or occlusion of one or more visceral arteries. It represents a therapeutic challenge and diagnosis and treatment require close interdisciplinary cooperation between gastroenterologist, vascular surgeon and radiologist. Although endovascular treatment modalities have been developed, the number of restenoses ultimately resulting in treatment failure is high. In patients fit for open surgery, the visceral arteries should be revascularized conventionally. These patients will then experience long term relief from the symptoms, a better quality of life and a better overall survival.

First successful complete replantation of a traumatic hemipelvectomy: follow-up after 30 months.

Traumatic hemipelvectomy is a severe, however rare injury associated with high lethality. Up to now, immediate surgical completion of the amputation has been recommended as a lifesaving therapy. We present a case of near complete hemipelvectomy with open fracture of the ileosacral joint, wide open symphysis and severe soft tissue trauma including a decollement around the pelvis. Successful complete replantation was performed by primary internal stabilisation and revascularisation using vascular grafts. In the further hospital course, numerous revisions of the soft tissue injury and reconstructive surgery were needed. Thirty months later, the patient's condition is physically and psychologically stable and he is able to walk using crutches. The key point of successful management was skilled emergency damage control surgery followed by dedicated surgical care to avoid septic complications.

Altered in-stent hemodynamics may cause erroneous upgrading of moderate carotid artery restenosis when evaluated by duplex ultrasound.

OBJECTIVE: To assess the influence of stent application on in-stent hemodynamics under standardized conditions. METHODS: Ovine common carotid arteries before and after stent (6 × 40 mm, sinus-Carotid-RXt, combined open-closed cell design; Optimed, Ettlingen, Germany) application were used. Plastic tubes, 10 mm in length, simulating stenosis were placed in the middle of the applied stent to induce different degrees of stenosis (moderate 57.8% and severe 76.4%). Flow velocity and dynamic compliance were, respectively, measured with ultrasound and laser scan; proximal, in-stent, and distal to the stented arterial segment (1 cm proximal and distal) in a pulsatile ex vivo circulation system. RESULTS: Stent insertion caused the in-stent peak systolic velocity to increase 22% without stenosis, 31% with moderate stenosis, and 23% with severe stenosis. Stent insertion without stenosis caused no significant increase in in-stent end-diastolic velocity (EDV) but a 17% increase with moderate stenosis. In severe stenosis, EDV was increased 56% proximal to the stenosis. Compliance was reduced threefold in the middle of the stented arterial segment where flow velocity was significantly increased. CONCLUSIONS: With or without stenosis, stent introduction caused the in-stent peak systolic velocity to become significantly elevated compared with a nonstented area. EDV was also increased by stent insertion in the case of moderate stenosis. The stent-induced compliance reduction may be causal for the increase in flow velocity since the stent-induced flow velocity elevation appeared in the stented area with low compliance. Because of altered hemodynamics caused by stent introduction when measured by duplex ultrasound, caution is prudent in concluding that carotid artery stenting is associated with a higher restenosis rate than carotid endarterectomy. Mistakenly upgrading moderate to severe restenosis could result in unnecessary reintervention. CLINICAL RELEVANCE: Clinical experience and prior studies support the supposition that restenosis after carotid artery stenting in carotid lesions displays erroneously elevated velocity when evaluated by duplex ultrasound (DUS), thus contributing to misleading interpretation of the degree of stenosis. This study, in contrast to studies of other groups, employs exactly the same conditions to measure flow with DUS in an unstented and then stented section of the carotid artery. Since DUS is the first-choice tool for carotid artery evaluation, knowledge about inexactness of the method is essential to avoid errors in treatment or follow-up decisions.

Risk of gas embolism in hand-assisted versus total laparoscopic hepatic resection.

Laparoscopic hepatic resection represents an alternative to open surgery in patients with advanced underlying hepatic disease. Management of haemorrhage and the risk of gas embolism are the major problems in laparoscopic liver surgery. In this study, safety and efficacy of liver dissection using ultrasonic energy was investigated in hand-assisted versus total laparoscopic surgery. The study had a special emphasis on evaluating the risk of gas embolism during both procedures. Female pigs were divided into two groups for A) total laparoscopic (n=7), and B) hand-assisted laparoscopic (n=7) hepatic resection. For tissue dissection, an ultrasound aspirator (CUSA) was used in both groups. Laparoscopic procedure was performed under a CO2 pneumoperitoneum (intraperitoneal pressure: 12 mmHg). Before dissection, a Pringle manoeuver was carried out. The anaesthetized pigs were monitored haemodynamically by an arterial line and Swan-Ganz catheter. Transoesophageal echocardiography (TEE) was performed with special attention to the right atrium and ventricle. Gas emboli were graded according to size and correlated with haemodynamic and blood-gas data. In both groups, the ultrasound-aspirator enabled an effective tissue dissection. In total laparoscopic hepatic resection, TEE monitoring disclosed gas embolism in 5/7 (71%) animals. In 3/7 (42%) animals, gas embolism was accompanied by a sequence of cardiac arrhythmia. No direct correlation was noted between episodes of embolism and blood-gas variables. None of the pigs died after episodes of embolization. In hand-assisted liver resection, no air embolism was noted. The internal hand impressively facilitated organ exposure and provided an immediate and efficient haemorrhage control. The use of an ultrasound aspirator system enables an effective laparoscopic hepatic dissection. Total laparoscopic liver dissection is at increased risk for gas embolism, whereas hand-assisted laparoscopic procedure appears to reduce this risk. Due to tactile response and facilitated retraction of the liver parenchyma, the hand-assisted procedure shows impressive advantages in laparoscopic liver surgery.