Mitochondrial respiration in peripheral arterial disease depends on stage severity.

Peripheral arterial disease (PAD) is an increasing cause of morbidity and its severity is graded based on clinical manifestation. To investigate the influence of the different stages on myopathy of ischemic muscle we analysed severity-dependent effects of mitochondrial respiration in PAD. Eighteen patients with severe PAD, defined as chronic limb-threatening ischemia, 47 patients with intermittent claudication (IC) and 22 non-ischemic controls were analysed. High-resolution respirometry (HRR) was performed on muscle biopsies of gastrocnemius and vastus lateralis muscle of patients in different PAD stages to investigate different respiratory states. Results from HRR are given as median and interquartile range and were normalized to citrate synthase activity (CSA), a marker for mitochondrial content. In order to account for inter-individual differences between patients and controls, we calculated the ratio of O2-flux in gastrocnemius muscle over vastus muscle ('GV ratio'). CSA of the gastrocnemius muscle as a proxy for mitochondrial content was significantly lower in critical ischemia compared to controls. Mitochondrial respiration normalized to CSA was higher in IC compared to controls. Likewise, the GV ratio was significantly higher in IC compared to control. Mitochondrial respiration and CSA of PAD patients showed stage-dependent modifications with greater changes in the mild PAD stage group (IC).

Identification of Perioperative Procedural and Hemodynamic Risk Factors for Developing Colonic Ischemia after Ruptured Infrarenal Abdominal Aortic Aneurysm Surgery: A Single-Centre Retrospective Cohort Study.

(1) Background: This retrospective study evaluated perioperative and intensive care unit (ICU) variables to predict colonic ischemia (CI) after infrarenal ruptured abdominal aortic aneurysm (RAAA) surgery. (2) Materials and Methods: We retrospectively analyzed the data of the patients treated for infrarenal RAAA from January 2011 to December 2020 in our hospital. (3) Results: A total of 135 (82% male) patients were admitted to ICU after treatment of infrarenal RAAA. The median age of all patients was 75 years (IQR 68-81 years). Of those, 24 (18%) patients developed CI, including 22 (92%) cases within the first three postoperative days. CI was found more often after open repair compared to endovascular treatment (22% vs. 5%, p = 0.021). Laboratory findings in the first seven PODs revealed statistically significant differences between CI and non-CI patients for serum lactate, minimum pH, serum bicarbonate, and platelet count. Norepinephrine (NE) was used in 92 (68%) patients during ICU stay. The highest daily dose of norepinephrine was administered to CI patients at POD1. Multivariable analysis revealed that NE > 64 µg/kg (RD 0.40, 95% CI: 0.25-0.55, p < 0.001), operating time ≥ 200 min (RD 0.18, 95% CI: 0.05-0.31, p = 0.042), and pH < 7.3 (RD 0.21, 95% CI: 0.07-0.35, p = 0.019), significantly predicted the development of CI. A total of 23 (17%) patients died during the hospital stay, including 8 (33%) patients from the CI group and 15 (7%) from the non-CI group (p = 0.032). (4) Conclusions: CI after RAAA is a sever complication occurring most frequently within the first 3 postoperative days. Our study identified many surrogate markers associated with colonic ischemia after aortic RAAA, including norepinephrine dose > 64 µg/kg, operating time ≥ 200 min, and PH < 7.3. Future studies are needed to support these results.

Outcomes of Endurant II Stent Graft According to Anatomic Severity Grade Score.

OBJECTIVES: This study's objective was to evaluate Endurant II (Medtronic Inc, Minneapolis, Minnesota) stent graft's early and midterm outcomes and compare the results according to the anatomic severity grade (ASG) scores. METHODS: This was a retrospective study of patients treated with the Endurant II stent graft between January 2013 and May 2021. The patients were divided into 2 independent groups, including those with a low ASG score (score <14) and a high ASG score (score >14). RESULTS: A total of 165 consecutive patients (89% males, age 74±8 years) were included. There were 110 (67%) patients in the low-score group and 55 (33%) patients in the high-score group. Technical success was achieved in all cases. Primary clinical success at 30 days was 100% and at 1 year was 96%. Median operative time was longer in the high-score group with no statistical significance (133 vs 120 minutes, p=0.116). The median dose area product of low-score patients (50.9 Gy·cm2; IQR 22.4-75.5 Gy·cm2) was significantly lower than high-score patients (85.0 Gy·cm2; IQR 46.5-127.9 Gy·cm2) with p=0.025. Median fluoroscopic time was lower in low-score patients (17 minutes; IQR 13-24 minutes) compared with high-score patients (19 minutes; IQR 16-23 minutes) without a significant difference at p=0.148. At a midterm follow-up of 32 months (range 2-63 months), combined complications (29% vs 8%, p<0.001) and implant-related complications (13% vs 4%, p=0.043) were higher in the high-score group. Systemic complications at 30 days were higher in the high-score group without a statistically significant difference (15% vs 11%, p=0.500). The Kaplan-Meier estimate of freedom from reintervention was significantly higher in the low-risk group at 1 (97% vs 90%), 2 (96% vs 88%), and 3 years (96% vs 85%) with (p=0.035). The cumulative survival rate was significantly higher in the low-score group than high-score group (p=0.001) at 1 (99% vs 87%), 2 (98% vs 85%), and 3 years (96% vs 82%). CONCLUSIONS: Endurant II endovascular aneurysm repair seems to be safe in both low-score and high-score patients. However, patients in the high-score group showed more implant-related complications and midterm mortalities than those in the low-score group.

Outcomes of Candida and Non-Candida Aortic Graft Infection.

OBJECTIVE: To evaluate and compare the outcomes of Candida- and non-Candida-associated aortic graft infections. METHODS: We retrospectively analyzed the data from patients treated for aortic graft infection from 2015 to 2021 in our hospital. RESULTS: A total of 66 patients (56 men; median age, 69 years; range, 50-87 years) were admitted with aortic graft infection, including 21 (32%) patients in the Candida group and 45 (68%) in the non-Candida group. The average time between initial operation and presentation of aortic graft infection was 50 months (range, 1-332 months). Graft-enteric fistulas (GEFs) were more often in the Candida group (57% vs 27%, P = .017). The most proven causative fungal specimen was C. albicans in 16 (76%) patients. Non-albicans Candida was found in 9% of all patients and 29% of the Candida patients. The median ICU length of stay was longer in the Candida group than non-Candida (10 vs 9 days, P = .012). Additionally, the median hospital length of stay was longer in the Candida group (33 vs 22 days, P = .048). There were no statistically significant differences between Candida and non-Candida groups according to the in-hospital mortality (24% vs 24%, P = .955), and 1-year mortality (38% vs 38%, P = .980). CONCLUSIONS: Patients with bacterial and fungal aortic graft infections have high rates of morbidity and mortality. We found no significant differences in postoperative morbidity and mortality between Candida and non-Candida patients. However, the ICU and hospital length of stay were longer in the Candida group.

A Modified Run-Off Resistance Score from Cross-Sectional Imaging Discriminates Chronic Critical Limb Ischemia from Intermittent Claudication in Peripheral Arterial Disease.

Atherosclerotic peripheral arterial disease (PAD) leads to intermittent claudication (IC) and may progress into chronic limb-threatening ischemia (CLTI). Scoring systems to determine the atherosclerotic burden of a diseased extremity have been developed. This study aimed to evaluate a modification of the run-off resistance (mROR) score for its usability in cross-sectional imaging. The mROR was determined from preoperative imaging of patients undergoing revascularization for PAD. A total of 20 patients with IC and 20 patients with CLTI were consecutively included. A subgroup analysis for diabetic patients was conducted. The mROR was evaluated for its correlation with disease severity and clinical covariates. Patients with CLTI were older; cardiovascular risk factors, diabetes, and ASA 4 were more frequent. The mROR scores were higher in CLTI than in IC. In diabetic patients, no difference was detected between CLTI and IC. In CLTI, non-diabetic patients had a higher mROR. The mROR score is positively correlated with the severity of PAD and can discriminate CLTI from IC. In diabetic patients with CLTI, the mROR is lower than in non-diabetic patients. The mROR score can be determined from cross-sectional imaging angiographies. It may be useful for clinicians helping with vascular case planning, as well as for scientific purposes.

Evaluation of Open Surgical and Endovascular Treatment Options for Visceral Artery Erosions after Pancreatitis and Pancreatic Surgery.

PURPOSE: To report and compare the results of endovascular and open surgical treatment for erosion bleeding of visceral arteries following pancreatitis and pancreatic surgery. MATERIALS AND METHODS: This retrospective study included 65 consecutive patients (46 males, mean age 63 ± 14 years) presenting with visceral artery erosions between January 2011 and December 2020. Endpoints were technical success, freedom from reintervention, stent-graft-related complications, and 30-day and one-year mortality. RESULTS: The causes of erosion bleeding included complications of surgical treatment for the pancreas and upper gastrointestinal tract (75%), pancreatitis (19%), and spontaneous bleeding (6%). Pancreatectomy was performed in 34 (52%) patients, representing 2% of all pancreatectomy procedures (n = 1645) performed in our hospital during the study period. A total of 37 (57%) patients underwent endovascular treatment (EVT), and 28 (43%) patients had open surgery (OS) as a primary treatment. Eight of 37 (22%) patients in the EVT group underwent stent-graft treatment of the eroded vessels and 28 (78%) coil embolization. Six (9%) patients underwent reintervention with no significant differences between EVT and OS groups (11% vs. 7%, p = 0.692). Postoperative morbidity and complications in 52% of all patients were higher in the OS group than in the EVT group (41% vs. 68%, p = 0.029). The in-hospital 30-days mortality rate for all patients was 25%, and it was higher in the OS group than in the EVT group (14% vs. 39%, p = 0.017). CONCLUSIONS: An endovascular-first strategy for treating visceral arteries erosions may be preferred to reduce the complications associated with open surgery if patients are hemodynamically stable and have no anastomotic insufficiency. Endovascular treatment may be associated with better in-hospital survival when compared to primary open surgery. Further studies are required to identify the optimal approach.

Perioperative risk prediction using the POSSUM and V-POSSUM models in symptomatic carotid stenosis.

Background: This study aimed to evaluate risk factors for adverse outcomes and perioperative stroke and death in patients with symptomatic carotid stenosis undergoing open endarterectomy (CEA). The second objective was to assess the predictive value of the POSSUM and V-POSSUM models for predicting morbidity and mortality from CEA in symptomatic carotid stenosis. Patients and methods: A retrospective observational study of all patients admitted to a single center who underwent CEA for symptomatic carotid stenosis was performed. 320 patients from 1999 to 2013 were included. Postoperative complications, 30-day survival, and stroke rates were recorded. The observed outcomes were compared to the POSSUM and V-POSSUM expected mortality (observed to expected ratio (O:E)). Results: The mean age was 68.1±10.0 years. 215 patients were male (67%). Risk factors for surgical complications were: age, with a higher risk in both groups of less than 60 years and more than 75 years of age (p=0.04), a higher ASA score (p=0.04), and hyperlipidemia (p=0.017). Risk factors for the combined endpoint stroke or death were a higher ASA category (p<0.001), stroke as indication for CEA (p 0.022), and a high degree of stenosis (p=0.019). For POSSUM predicted mortality, there was a good O:E ratio in the two lowest risk groups, but a 2-fold overprediction of death or stroke in the two high-risk strata. The area under the curve (AUC) was 0.58 (95% CI: 0.43-0.73). The V-POSSUM showed a better fit in the high-risk groups, but an underprediction of mortality in the low-risk strata. Conclusions: Age and comorbid conditions are risk factors for adverse outcomes after CEA. The V-POSSUM model is better than POSSUM to predict postoperative death and stroke after CEA in patients with symptomatic carotid stenosis and a high preoperative physiological score. In patients with low physiological scores, both POSSUM and V-POSSUM show a limited predictive value.

Effect of Revascularization on Intramuscular Vascular Endothelial Growth Factor Levels in Peripheral Arterial Disease.

Vascular endothelial growth factor (VEGF) is a potent driver of angiogenesis, which may help to relieve ischemia in peripheral arterial disease (PAD). We aimed to investigate the role of intramuscular VEGF in ischemic and non-ischemic skeletal muscle in PAD patients before and after surgical or endovascular revascularization and different stages of PAD. Biopsies of the gastrocnemius and vastus muscles from twenty PAD patients with stenosis or occlusion of the superficial femoral artery were obtained both during revascularization and 8 weeks postoperatively. The gastrocnemius muscle was considered ischemic, while vastus muscle biopsies served as intraindividual controls. The levels of vascular endothelial growth factor in muscle lysates were then determined by ELISA. Preoperative VEGF levels were significantly higher in ischemic muscles compared to the controls (98.07 ± 61.96 pg/mL vs. 55.50 ± 27.33 pg/mL, p = 0.004). Postoperative values decreased significantly (p = 0.010) to 54.83 ± 49.60 pg/mL in gastrocnemius biopsies. No significant change was observed in vastus muscle biopsies, with mean postoperative VEGF values found at 54.16 ± 40.66 pg/mL. Since all patients still had indications for revascularization, impairment of angiogenesis mechanisms can be assumed. More research about angiogenesis in PAD is needed with the ultimate goal to improve conservative treatment.

Isolated Ruptured Paravisceral Penetrating Aortic Ulcers.

BACKGROUND: The goal of this study is to investigate the clinical presentation, treatment options, and outcomes of the patients with isolated ruptured paravisceral penetrating aortic ulcers (PV-PAU). METHODS: All patients presenting with acute aortic syndrome from 2015 to 2020 were screened, of which patients with isolated ruptured PV-PAU were included in this retrospective study. Study endpoints were the assessment of treatment options, technical success, and clinical outcome. Outcome measures included major perioperative complications and mortality. RESULTS: Sixteen patients (11 men; median age 68; IQR 60 - 75 years) presented with isolated ruptured PV-PAU were included in this study. The median follow-up was 25 months (range 1 - 51). Ruptured PV-PAUs represented 12.3% of the ruptured aortic aneurysms in all locations. PV-PAUs were found in segment A (n = 8, 50%), segment B (n = 5, 31%), and segment C (n = 3, 19%). PV-PAUs showed a mean protrusion distance of 27±10 mm, a mean neck diameter of 21 ± 7 mm, and maximal aortic diameter of 50 ± 11 mm. Five patients (31%) showed hemodynamic instability on admission and needed intense fluid resuscitation. Of those, 2 patients needed urgent laparotomy with a fast transabdominal supraceliac aortic clamping, one needed an aortic balloon occlusion to obtain rapid aortic control. The open aortic repair was the most frequently performed surgery (11/16, 69%), followed by hybrid procedures (3/16) and parallel graft chimney technique (2/16). Two patients died during the follow-up, calculating for in-hospital and 1-year mortality rates of 6 - 12%, respectively. The postoperative morbidity rate was 31%. Postoperative complications included acute renal failure (31%), pneumonia (25%), and 1case of ischemic colitis (6%). No spinal cord ischemia was reported. CONCLUSIONS: Ruptured PV-PAU is a rare and challenging diagnostic and therapeutic entity. Open aortic repair seems to be a reliable option in treating patients with isolated ruptured PV-PAUs. Hybrid procedures and parallel stent-graft techniques can only be used in selected patients.

Preoperative and ICU Scoring Models for Predicting the In-Hospital Mortality of Patients With Ruptured Abdominal Aortic Aneurysms.

OBJECTIVES: This study's objective was to compare several preoperative and intensive care unit (ICU) prognostic scoring systems for predicting the in-hospital mortality of ruptured abdominal aortic aneurysms (RAAAs). DESIGN: Retrospective cohort study. SETTING: Single tertiary university center. PARTICIPANTS: The study comprised 157 patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 157 patients (82% male) presented with RAAA at Charité University Hospital from January 2011 to December 2020. The mean age was 74 years (standard deviation ten years). In-hospital mortality was 29% (n = 45), of whom nine patients (6%) died en route to the operating room, 13 (8%) on the operating table, and 23 (15%) in the ICU. A total of 135 patients (86%) were admitted to the ICU. All six models demonstrated good discriminating performance between survivors and nonsurvivors. Overall, the area under the curve (AUC) for RAAA preoperative scores was greater than those for ICU scores. The largest AUC was achieved with the Vascular Study Group of New England (VSGNE) RAAA risk score (AUC = 0.87 for all patients, AUC = 0.84 for patients admitted to the ICU), followed by Hardman Index (AUC = 0.83 for all patients, AUC = 0.81 for patients admitted to the ICU), and Glasgow Aneurysm Score (AUC = 0.74 for all patients, AUC = 0.83 for patients admitted to the ICU). The largest AUC for ICU scores (only patients admitted to the ICU) was achieved with Simplified Acute Physiology Score II (0.75), followed by Sepsis-related Organ Failure Assessment (0.73), and Acute Physiology and Chronic Health Evaluation II (0.71). CONCLUSIONS: Preoperative and ICU scores can predict the mortality of patients presenting with RAAA. In addition, the discriminatory ability of preoperative scores between survivors and nonsurvivors was larger than that for ICU scores.