Urinary vanin-1 as a novel biomarker for survival in peripheral artery disease

BACKGROUND

Chronic kidney disease is associated with increased rates of incidence, morbidity, and mortality in lower-extremity peripheral artery disease (PAD). No specific marker for a functional risk assessment of kidney disease in PAD is known, especially at the early stages. Thus, we speculated that urinary vanin-1 (uVNN1), a marker of oxidative stress even in early kidney injury, could further stratify outcome assessment in patients with PAD.

METHODS

Patients with stable PAD (n = 304) of the Vienna medical cohort were followed up for up to 10 years and the outcome was assessed by central death database queries. uVNN1 was measured by enzyme-linked immunosorbent assay (ELISA) at study inclusion and normalized to urinary creatinine (uVNN1/Cr). During the observation time (9.3, 7.0-9.8 years), 104 patients died, 54.8% of which were due to cardiovascular causes.

RESULTS

uVNN1/Cr was associated with a urine albumin-creatinine ratio (UACR) (R = 0.166, p = 0.004) but not with an estimated glomerular filtration rate (R = 0.102, p = 0.077). Levels of uVNN1/Cr did not differ between asymptomatic and symptomatic PAD (p = 0.406). Kaplan-Meier curves showed a clear-cut association with higher all-cause (log-rank p = 0.034) and cardiovascular mortality (log-rank p = 0.032) with higher uVNN1/Cr levels. Similarly, significant associations for all-cause (hazard ratio [HR] 1.34, 95% CI [1.08-1.67], p = 0.009) and cardiovascular mortality (HR 1.45, 95% CI [1.06-1.99], p = 0.020) could be seen in multivariable Cox regression models.

CONCLUSIONS

uVNN1/Cr showed an independent association with both all-cause and cardiovascular mortality in patients with PAD and was associated with early kidney disease. Thus, uVNN1 could be a useful marker for risk stratification of kidney disease in PAD.

Capillaroscopic differences between primary Raynaud phenomenon and healthy controls indicate potential microangiopathic involvement in benign vasospasms

BACKGROUND

For primary Raynaud phenomenon (PRP), an otherwise unexplained vasospastic disposition is assumed. To test the hypothesis of an additional involvement of distinct ultrastructural microvascular alterations, we compared the nailfold capillary pattern of patients with PRP and healthy controls.

METHODS

A total of 120 patients with PRP (with a median duration of vasospastic symptoms of 60 [IQR: 3-120] months) were compared against 125 controls. In both groups, nailfold capillaroscopy was performed to record the presence of dilatations, capillary edema, tortuous capillaries, ramifications, hemorrhages, and reduced capillary density and to determine a semiquantitative rating score. Further, the capacity of finger skin rewarming was investigated by performing infrared thermography in combination with cold provocation.

RESULTS

Unspecific morphologic alterations were found in both, PRP, such as controls, whereby the risk for PRP was four times as high in the presence of capillary dilations (CI: 2.3-7.6) and five times as high if capillary density was reduced (CI: 1.9-13.5). Capillary density correlated with thermoregulatory capacity in both hands in the PRP group, but not in controls. In addition, a negative correlation between the microangiopathy score and the percentage degree of rewarming in both hands was found for patients with PRP only.

CONCLUSION

We found specific differences within the microvascular architecture between patients with PRP and controls. As a conclusion, PRP may not be an entirely benign vasospastic phenomenon, but might be associated with subtle microcirculatory vasculopathy. In addition, we suggest that the implementation of a scoring system might serve as guidance in the diagnostic process at least of patients with long-standing PRP.

Rescue From Permanent Kidney Injury in Acute Thrombosis of Both Renal Veins, the Inferior Vena Cava, and Both Iliofemoral Veins by Catheter-Based Thrombectomy

CASE

A 33-year-old man with previously diagnosed lupus membranous nephropathy presented with painful swelling in both legs. Laboratory tests revealed acute kidney injury, and imaging studies by duplex ultrasound and computed tomography scan showed acute thrombosis of both renal veins, the infrahepatic inferior vena cava, and both iliofemoral venous segments. Initially, pharmacomechanical thrombolysis led to an insufficient morphological result. The therapeutic breakthrough was achieved by catheter-based mechanical thrombectomy of the infrarenal vena cava and both renal veins, which successfully cleared all affected venous segments from thrombus, paralleled by improvement of the patient's condition. However, after 1 week, the patient experienced recurrent thrombosis of the right renal vein with hemorrhagic infarction of the right kidney. After further optimization of immunomodulatory and antithrombotic therapy, a repeated catheter-based mechanical thrombectomy resulted in sustained clinical improvement and preservation of renal venous drainage and kidney function.

CONCLUSION

Extensive acute thrombosis of both renal veins, the inferior vena cava, and both iliofemoral venous segments is a rare emergency potentially threatening kidney function. Immediate effective thrombus removal is essential to preserve kidney function and can be achieved by catheter-based mechanical thrombectomy embedded in a comprehensive immunomodulatory and antithrombotic therapeutic concept.

CLINICAL IMPACT

This case demonstrated the efficacy of a catheter-based therapeutic approach in patients with extensive thrombosis of the venous system. A catheter-based approach must be embedded in a comprehensive medical therapeutic concept, which is essential to achieve a sustainable result.

Serum Trefoil Factor-3 Predicts Survival in Peripheral Artery Disease

Trefoil factor 3 (TFF3) has been studied in processes leading to atherosclerosis. Data are scarce in manifest disease and missing in peripheral artery disease (PAD). This study aims to elucidate TFF3 with disease stages, degrees of atherosclerosis, and outcomes. TFF3 was measured in serum in 364 PAD patients without critical limb ischemia and mild to moderate chronic kidney disease (CKD). Mortality data were retrieved from the Austrian central death registry (median observation 9.6 years). Survival analyses were performed using Cox regression and the Kaplan-Meier method. A negative association between ankle-brachial index and TFF3 (P < .001) was observed, while levels were similar in asymptomatic and symptomatic PAD. TFF3 increased with history of cardiovascular and cerebrovascular disease (P < .001). TTF3 was associated with the estimated glomerular filtration rate (R = -0.617, P < .001) and urinary albumin-creatinine ratio (R = 0.229, P < .001). One SD increase in TFF3 showed a worsening in all-cause mortality (hazard ratio 1.68, CI 1.37-2.05) which persisted after multiple adjustment for cardiovascular risk, inflammatory, and angiogenetic markers (hazard ratio 1.35, CI 1.01-1.81). This study is the first to link TFF3 with both disease markers and outcomes in PAD. TFF3 demonstrated associations with renal function, PAD severity measured by ankle-brachial index, and additional atherosclerotic burden in PAD.

Closure of Post-thrombotic Iliac Arteriovenous Fistulas by Iliac Vein Recanalization

PURPOSE

The purpose of this study was to report the closure of iliac arteriovenous fistulas associated with a post-thrombotic iliac vein occlusion by iliac venous stent recanalization.

CASE REPORT

An 80-year-old woman presented with a worsening painful swelling of her left leg after an iliofemoral deep vein thrombosis 6 months ago. Duplex ultrasound and magnetic resonance venography revealed a post-thrombotic obstruction of her iliac veins as well as several arteriovenous fistulas between branches of her left external and internal iliac arteries and adjacent diseased venous segments. In a first attempt, coil embolization did not sustainably close these iliac arteriovenous fistulas. Direct stent recanalization of the chronically diseased iliofemoral venous segment, however, resulted in an immediate closure of arteriovenous shunt flow and subsequent improvement of clinical symptoms. Six months after iliac vein stent recanalization, still no fistulas could be detected any more, venous stents were fully patent, and the patient was free of symptoms.

CONCLUSION

Post-thrombotic iliofemoral obstructions might be associated with the development of arteriovenous fistulas. Direct stent recanalization of the chronically occluded veins results in closure of related arteriovenous fistulas.

CLINICAL IMPACT

This case suggests that the combined occurrence of post-thrombotic venous obstructions with arteriovenous fistulas, which are related to aforementioned venous lesions, should be evaluated for primary venous stent recanalization rather than fistula embolization.

Impact of thrombosis location on walking capacity: a cohort study of patients with acute deep vein thrombosis

Background

Data on walking impairment during the acute phase of deep vein thrombosis (DVT) are limited.

Objectives

This study aimed to assess the degree of walking impairment in patients with acute DVT, with a particular focus on the relation to the DVT's anatomical location.

Methods

Patients with sonographically confirmed DVT were eligible for inclusion in this cohort study. Pain-free walking distance (PWD) and maximum walking distance (MWD) were determined using standardized treadmill ergometer tests and analyzed in relation to DVT location. The impact of previous DVT on walking capacity was evaluated in an exploratory analysis.

Results

The study included 64 patients (31% women; median age, 55 years). The median (IQR) time from diagnosis to exercise test was 3 (1-5) days. Patients with suprainguinal DVT demonstrated significantly shorter median (IQR) MWD than those with infrainguinal DVT (130 (61-202) m vs 565 (128-750) m; P < .01), while PWD did not significantly differ (PWD: 20 (0-30) m vs 40 (0-222) m; P = .14). The proportion of patients who had to terminate treadmill tests prematurely was higher in patients with suprainguinal DVT (91.7% vs 57.7%; P = .04). PWD and MWD seemed to be similar in patients with and without a history of DVT. Premature test termination and suprainguinal DVT location were associated with reduced quality of life, as measured by the EuroQoL Group 5-Dimension 5-Level questionnaire and visual analog scale.

Conclusion

Suprainguinal DVT was linked to a more pronounced walking impairment compared with infrainguinal DVT. Limited walking capacity was associated with a reduced quality of life.

Micro- and Macrovascular Effects of Inflammation in Peripheral Artery Disease-Pathophysiology and Translational Therapeutic Approaches

Inflammation has a critical role in the development and progression of atherosclerosis. On the molecular level, inflammatory pathways negatively impact endothelial barrier properties and thus, tissue homeostasis. Conformational changes and destruction of the glycocalyx further promote pro-inflammatory pathways also contributing to pro-coagulability and a prothrombotic state. In addition, changes in the extracellular matrix composition lead to (peri-)vascular remodelling and alterations of the vessel wall, e.g., aneurysm formation. Moreover, progressive fibrosis leads to reduced tissue perfusion due to loss of functional capillaries. The present review aims at discussing the molecular and clinical effects of inflammatory processes on the micro- and macrovasculature with a focus on peripheral artery disease.

Preprocedural imaging modalities in patients undergoing iliocaval venous recanalization and stent placement

PURPOSE

To determine the diagnostic accuracy of preinterventional imaging modalities in patients being evaluated for iliocaval venous recanalization and stent placement.

METHODS

Consecutive patients with iliocaval postthrombotic obstructions or nonthrombotic iliac vein lesions (NIVL), who were scheduled for recanalization, underwent duplex ultrasound (DUS), magnetic resonance venography (MRV), multiplanar venography (MPV), and intravascular ultrasound (IVUS). The diagnostic accuracies of DUS, MRV, and MPV were analyzed using IVUS as reference.

RESULTS

A total of 216 limbs in 108 patients (80 patients with postthrombotic obstructions, 28 patients with NIVL) were examined. In patients with postthrombotic obstructions, the diagnostic sensitivities for the detection of lesions of the common femoral vein were 81% (95% CI 71-89%) for DUS, 76% (95% CI 65-85%) for MRV, and 86% (95% CI 76-93%) for MPV. The sensitivities for detecting lesions of the iliac veins were 96% (95% CI 89-99%) for DUS, 99% (95% CI 92-100%) for MRV, and 100% (95% CI 94-100%) for MPV. Regarding the inferior vena cava, the sensitivities were 44% (95% CI 24-65%) for DUS, 52% (95% CI 31-73%) for MRV, and 70% (95% CI 47-86%) for MPV. The sensitivities for detecting NIVL were 58% (95% CI 34-79%) for DUS, 90% (95% CI 68-97%) for MRV, and 95% (95% CI 73-99%) for MPV.

CONCLUSION

In patients scheduled for recanalization of iliocaval postthrombotic obstructions, the sensitivities of DUS, MRV, and MPV were similar. In patients with suspected inferior vena cava involvement and in patients with NIVL, additional imaging with MR or conventional venography is required.

Toll-like Receptors as Pro-Thrombotic Drivers in Viral Infections: A Narrative Review

Toll-like receptors (TLRs) have a critical role in the pathogenesis and disease course of viral infections. The induced pro-inflammatory responses result in the disturbance of the endovascular surface layer and impair vascular homeostasis. The injury of the vessel wall further promotes pro-thrombotic and pro-coagulatory processes, eventually leading to micro-vessel plugging and tissue necrosis. Moreover, TLRs have a direct role in the sensing of viruses and platelet activation. TLR-mediated upregulation of von Willebrand factor release and neutrophil, as well as macrophage extra-cellular trap formation, further contribute to (micro-) thrombotic processes during inflammation. The following review focuses on TLR signaling pathways of TLRs expressed in humans provoking pro-thrombotic responses, which determine patient outcome during viral infections, especially in those with cardiovascular diseases.

NT-proBNP as a surrogate for unknown heart failure and its predictive power for peripheral artery disease outcome and phenotype

Patients with peripheral artery disease (PAD) are at high risk of excess mortality despite major improvements in multimodal pharmacotherapy for cardiovascular disease. However, little is known about co-prevalences and implications for the combination of heart failure (HF) and PAD. Thus, NT-proBNP as a suggested surrogate for HF was evaluated in symptomatic PAD regarding long-term mortality. After approval by the institutional ethics committee a total of 1028 patients with PAD, both with intermittent claudication or critical limb ischemia were included after admission for endovascular repair and were followed up for a median of 4.6 years. Survival information was obtained from central death database queries. During the observation period a total of 336 patients died (calculated annual death rate of 7.1%). NT-proBNP (per one standard deviation increase) was highly associated with outcome in the general cohort in crude (HR 1.86, 95%CI 1.73-2.01) and multivariable-adjusted Cox-regression analyses with all-cause mortality (HR 1.71, 95%CI 1.56-1.89) and CV mortality (HR 1.86, 95% CI 1.55-2.15). Similar HR's were found in patients with previously documented HF (HR 1.90, 95% CI 1.54-2.38) and without (HR 1.88, 95%CI 1.72-2.05). NT-proBNP levels were independently associated with below-the-knee lesions or multisite target lesions (OR 1.14, 95% CI 1.01-1.30). Our data indicate that increasing NT-proBNP levels are independently associated with long-term mortality in symptomatic PAD patients irrespective of a previously documented HF diagnosis. HF might thus be highly underreported in PAD, especially in patients with the need for below-the-knee revascularization.

Temporal association between COVID-19 vaccination and Raynaud's phenomenon: A case series

COVID-19 vaccine-related adverse events are mostly minor to moderate, and serious events are rare. Single cases of Raynaud's phenomenon (RP) in temporal proximity to COVID-19 vaccination have been reported. Demographic data, medical history, and detailed information regarding vaccination status and RP characteristics were obtained from patients with confirmed RP after COVID-19 vaccination. Fifteen participants reported the initial manifestation of RP, which occurred in 40% after the first, in 33% after the second, and in 27% after the third vaccination. RP development and occurrence of episodes were not linked to any specific vaccine type. New onset of disease was observed in 40% of the vaccinees after BNT162b2, in 33% after mRNA-1273, and in 27% after ChAdOx1 vaccination. Three out of four participants with preexisting RP prior to COVID-19 vaccination reported aggravation in frequency and intensity after immunization. Although COVID-19 vaccination is pivotal in controlling the pandemic, the observed temporal association between vaccine administration and RP occurrence warrants global activities to support pharmacovigilance for the detection of adverse reactions, one of which may include RP.

A Case of Autoimmune Small Fiber Neuropathy as Possible Post COVID Sequelae

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is reported to induce and augment autoimmune processes. Moreover, postinfectious effects of coronavirus disease 2019 (COVID-19) are still poorly understood and often resemble symptoms of the acute infection phase. A patient with swollen extremities was presented to the Department of Angiology at the Medical University of Vienna with complaints of muscle and joint pain, paresthesia, and arterial hypertension with intense headache. Prior to these complaints, she had been suffering from various symptoms since November 2020, following a SARS-CoV-2 infection in the same month. These included recurrent sore throat, heartburn, dizziness, and headache. Paresthesia and muscle and joint pain started in temporal relation to a human papillomavirus (HPV) vaccination. Since the patient was suffering from severe pain, intensive pain management was performed. Skin and nerve biopsies revealed autoimmune small fiber neuropathy. The patient's condition could be related to COVID-19, as her first symptoms began in temporal relation to the SARS-CoV-2 infection. Furthermore, in the disease course, antinuclear (ANA) and anti-Ro antibodies, as well as anti-cyclic citrullinated peptide (anti-CCP) antibodies, could be detected. Together with the symptoms of xerophthalmia and pharyngeal dryness, primary Sjögren's syndrome was diagnosed. In conclusion, though biopsy results could not distinguish a cause of the disease, SARS-CoV-2 infection can be discussed as a likely trigger for the patient's autoimmune reactions.

Associations between nailfold capillary aberrations and autoantibodies in children and adults with Raynaud's phenomenon

OBJECTIVE

To characterise associations between individual nailfold capillary aberrations with autoantibodies in a cross-sectional study on children and adults with Raynaud's phenomenon (RP).

METHODS

Consecutive children and adults with RP and without previously known connective tissue disease (CTD) systemically underwent nailfold capillaroscopy and laboratory tests for the presence of antinuclear antibodies (ANA). The prevalence of individual nailfold capillary aberrations and ANA was assessed, and the associations between individual nailfold capillary aberrations and ANA were analysed separately in children and adolescents.

RESULTS

In total, 113 children (median age 15 years) and 2858 adults (median age 48 years) with RP and without previously known CTD were assessed. At least one nailfold capillary aberration was detected in 72 (64%) of included children and in 2154 (75%) of included adults with RP (children vs adults p<0.05). An ANA titre ≥1:80, ≥1:160 or≥1:320 was observed in 29%, 21% or 16% of included children, and in 37%, 27% or 24% of screened adults, respectively. While the occurrence of individual nailfold capillary aberrations was related to the presence of an ANA titre of ≥1:80 in adults (reduced capillary density, avascular fields, haemorrhages, oedema, ramifications, dilations and giant capillaries: each p<0.001), no comparable association between nailfold capillary aberrations and ANA was observed in children with RP without previously known CTD.

CONCLUSION

In contrast to adults, the association between nailfold capillary aberrations and ANA might be less pronounced in children. Further studies are warranted to validate these observations in children with RP.

Lipoprotein (a) and long-term outcome in patients with peripheral artery disease undergoing revascularization

BACKGROUND AND AIMS

Despite low LDL-C goals, the residual risk for further cardiovascular (CV) events in patients with peripheral artery disease (PAD) remains high. Lipoprotein (a) (Lp(a)) is a known risk factor for PAD incidence, but little is known regarding the outcome in patients with symptomatic PAD. Thus, this study investigates Lp(a) and CV mortality in PAD after endovascular repair.

METHODS

A total of 1222 patients with PAD in two cohorts according to Lp(a) assay in nmol/L (n = 964, Lip-LEAD-A) or mg/dl (n = 258, Lip-LEAD-B) were followed up for 4.3 (IQR 3.0-5.6) or 7.6 (IQR 3.2-8.1) years. Lp(a) was measured before endovascular repair for either intermittent claudication (IC) or critical limb ischemia (CLI). Outcome information was obtained from the federal death registry.

RESULTS

In Lip-LEAD-A, 141 CV-deaths occurred (annual calculated CV-death rate 3.4%), whereas 64 CV-deaths were registered in Lip-LEAD-B (annual calculated CV-death rate 3.3%). After adjustment for traditional CV risk factors Lp(a) was neither associated with outcome in Lip-LEAD-A (highest tertile HR 1.47, 95%CI [0.96-2.24]) nor in Lip-LEAD-B (highest tertile HR 1.34 [0.70-2.58]). Subanalyses for IC (HR 1.37 [0.74-2.55]; HR 1.10 [0.44-2.80], CLI (HR 1.55 [0.86-2.80], HR 3.01 [0.99-9.10]), or concomitant coronary artery disease (CAD; HR 1.34 [0.71-2.54]; HR 1.21 [0.46-3.17]) failed to show a significant association between Lp(a) and CV-mortality.

CONCLUSIONS

In this large-scale cohort of symptomatic PAD no association of elevated Lp(a) with CV mortality was found over a median observation period of 5 years. Thus, an even longer study including asymptomatic patients is warranted.

Covid-19 Vaccination and the issue of insurance status

Issue

It is estimated, that 11000 - 14000 people that live in Zurich do not have health insurance. For the vaccination against Covid-19 in Switzerland one had to register oneself on a website (Vacme) with your address and a Swiss health insurance number was required. This systematically excluded any people without insurance or Sans Papiers.

Description

To address this issue the city physician service Zurich organized a vaccination program for the uninsured from 14.06.2021 onward. To achieve this a code which could be used instead of the regular insurance number was organized and the staff recorded personal information of patients on site to remove language and technological barriers. Furthermore, the Police department was informed and agreed not to circulate the area of the vaccination service on vaccination days to minimize access-barriers for patients without legal residency.

Results

Between 14.06.2021 and 19.02.2022, 880 people came for vaccination of which 603 were clearly identifiable as individuals from vulnerable populations with no insurance. After initial organization, other vaccination centers in Switzerland were able to use the substitute number to vaccinate people without health insurance as well..

Lessons

There is a sizeable amount of people living without registration or/and health insurance. It is therefore critical not to forget these people when organizing public health measures, especially when addressing a pandemic or other infectious diseases (HIV, Hep C). Non-insurance is a known issue for universal access to care.

Acknowledgements: We would like to thank the hold crew of the ambulatorium kanonengasse at SAD

Key messages

• When fighting a pandemic it is of utmost importance to reach as many people as possible.

• Acess must be possible also for vulnernable people.

Covid-19 Vaccination and the issue of insurance status

Issue

It is estimated, that 11000 - 14000 people that live in Zurich do not have health insurance (∼3% of pop.). Covid-19 vaccination in Switzerland required an online registration (‘Vacme') with name, address and health insurance number. Health insurance in Switzerland is only accessible to people with registered residence in the country. This systematically excluded people without right of residence, health insurance or internet access.

Description

To address this issue the health service of the city Zurich organized a vaccination site for the uninsured from 14.06.2021 onward. To achieve this a simplified registration procedure was established, which allowed us to offer Vaccination to everybody, independent of their insurance status. Instead of the health insurance number, on site personal used a dummy number and the address of our site to register those patients. To remove language and technological barriers. In order to lower, the inhibition threshold for people without legal residence the Police department was informed and agreed not to circulate the area of the vaccination site on vaccination days.

Results

Between 14.06.2021 and 19.02.2022, 880 people came for vaccination of which 603 (69%) were clearly identifiable as individuals from non-insured populations. (See Graph)

Lessons

It is therefore critical not to forget these people when organizing public health measures, especially when addressing a pandemic or other infectious diseases (HIV, Hepatitis). A group specific information approach is of paramount importance to reach such subpopulations. Non-insurance is a known barrier for universal access to care.

Acknowledgements: We would like to thank the involved departments of the city Zurich, chief medical officer canton zurich, our collaboration partners and the staff of our vaccination site.

Key messages

HDL particle subclasses in statin treated patients with peripheral artery disease predict long-term survival

Low-density lipoprotein-cholesterol (LDL-C) reduction showed a strong reduction of cardiovascular (CV) event rates in CV disease. However, the residual risk of future CV events remains high, which especially extends to peripheral arterial disease (PAD). Nuclear magnetic resonance (NMR)-spectroscopy offers a novel method for analyses of the lipoprotein spectrum. This study investigates lipoprotein subclasses using NMR-spectroscopy and assesses implications for long-term survival in PAD. NMR-spectroscopy was performed by Nightingale Inc. in 319 patients with stable PAD and well-controlled CV risk factors. Patients were followed-up for ten years. During that period 123 patients (38.5%) died, of those 68 (21.3%) were defined as CV-deaths. Outcome data were analyzed by the Kaplan-Meier method and multivariable Cox regression for lipoprotein particles. Small and medium high-density lipoprotein-particles (S-HDL-P and M-HDL-P) showed a significant inverse association with all-cause mortality in Cox-regression analyses after multivariable adjustment (S-HDL-P hazard ratio 0.71, 95% confidence interval 0.57-0.88; M-HDL-P 0.72, 0.58-0.90) for each increase of 1 standard deviation. In contrast, cholesterol-rich x-large HDL-particles (XL-HDL-P) showed a positive association with all-cause mortality (1.51, 1.20-1.89). Only the association between XL-HDL-P and CV-death sustained multivariable adjustment (1.49, 1.10-2.02), whereas associations for S-HDL-P and M-HDL-P were attenuated (0.76, 0.57-1.01; 0.80, 0.60-1.06). This study shows a novel association for a beneficial role of S-HDL-P and M-HDL-P but a negative association with higher cholesterol-rich XL-HDL-P for long-term outcome in well-treated patients with PAD. Thus, these results provide evidence that NMR-measured HDL particles identify patients at high CV residual risk beyond adequate lipid-lowering therapy.

Platelet-to-Lymphocyte Ratio as Marker of Platelet Activation in Patients on Potent P2Y12 Inhibitors

A high platelet-to-lymphocyte ratio (PLR) has recently been associated with ischemic outcomes in cardiovascular disease. Increased platelet reactivity and leukocyte-platelet aggregate formation are directly involved in the progress of atherosclerosis and have been linked to ischemic events following percutaneous coronary intervention (PCI). In order to understand the relation of PLR with platelet reactivity, we assessed PLR as well as agonist-inducible platelet aggregation and neutrophil-platelet aggregate (NPA) formation in 182 acute coronary syndrome (ACS) patients on dual antiplatelet therapy with aspirin and prasugrel (n = 96) or ticagrelor (n = 86) 3 days after PCI. PLR was calculated from the blood count. Platelet aggregation was measured by multiple electrode aggregometry and NPA formation was determined by flow cytometry, both in response to ADP and SFLLRN. A PLR ≥91 was considered as high PLR based on previous data showing an association of this threshold with adverse ischemic outcomes. In the overall cohort and in prasugrel-treated patients, high PLR was associated with higher SFLLRN-inducible platelet aggregation (67 AU [50-85 AU] vs 59.5 AU [44.3-71.3 AU], P = .01, and 73 AU [50-85 AU] vs 61.5 AU [46-69 AU], P = .02, respectively). Further, prasugrel-treated patients with high PLR exhibited higher ADP- (15% [11%-23%] vs 10.9% [7.6%-15.9%], P = .007) and SFLLRN-inducible NPA formation (64.3% [55.4%-73.8%] vs 53.8% [44.1%-70.1%], P = .01) as compared to patients with low PLR. These differences were not seen in ticagrelor-treated patients. In conclusion, high PLR is associated with increased on-treatment platelet reactivity in prasugrel-treated patients, but not in patients on ticagrelor.

Microvascular rarefaction in patients with cerebrovascular events

Capillary density rarefaction and endothelial dysfunction contribute to chronic hypoperfusion and cerebral small vessel disease. Previous animal experiments revealed spatiotemporal microvascular remodeling directing post-stroke brain reorganization. We hypothesized that microcirculatory changes during acute cerebrovascular events could be reflected systemically and visualized sublingually. In a prospective observational trial in vivo sublingual sidestream darkfield videomicroscopy was performed in twenty-one patients with either acute stroke (n = 13 ischemic, n = 1 ischemic with hemorrhagic transformation and n = 2 hemorrhagic stroke) or transitory ischemic attacks (n = 5) within 24 h after hospital admission and compared to an age- and sex-matched control group. Repetitive measurements were performed on the third day and after one week. Functional and perfused total capillary density was rarefied in the overall patient group (3060 vs 3717 μm/mm², p = 0.001 and 5263 vs 6550 μm/mm², p = 0.002, respectively) and in patients with ischemic strokes (2897 vs. 3717 μm/mm², p < 0.001 and 5263 vs. 6550 μm/mm², p = 0.006, respectively) when compared to healthy controls. The perfused boundary region (PBR), which was measured as an inverse indicator of glycocalyx thickness, was markedly related to red blood cell (RBC) filling percentage (regarded as an estimate of microvessel perfusion) in the overall patient group (r = -0.843, p < 0.001), in patients with ischemic strokes (r = -0.82, p = 0.001) as well as in healthy volunteers (r = -0.845, p < 0.001). In addition, there were significant associations between platelet count or platelet aggregation values (as measured by whole blood impedance aggregometry) and microvascular parameters in the overall patient collective, as well as in patients with ischemic strokes. In conclusion, cerebrovascular events are associated with altered systemic microvascular perfusion.

Galectin-3 is linked to peripheral artery disease severity, and urinary excretion is associated with long-term mortality

BACKGROUND AND AIMS

Galectin-3 (Gal-3) is a biomarker involved in fibrosis and vascular inflammation. Gal-3 has been linked to chronic kidney disease (CKD) and patients with peripheral artery disease (PAD). Conflicting reports exist about the relevance of Gal-3 in PAD. The study aims to elucidate a possible link between serum and urinary Gal-3 and long-term survival in PAD patients without critical limb ischemia and mild to moderate CKD.

METHODS

Galectin-3 (Gal-3) was measured in serum (n = 311) and urine (n = 266) of PAD patients (age 69 (62-77) years) by bead-based multiplex assay. Urinary Gal-3 concentration was normalized to urine creatinine (cr) levels. Mortality data were retrieved from the Austrian central death registry after a median observation period of 9.2 years. Survival analyses were performed by the Kaplan-Meier method and Cox-regression.

RESULTS

Serum Gal-3 was higher in patients with claudication symptoms (p = 0.001) and correlated inversely with the patients' ankle-brachial index (R = -0.168, p = 0.009). Serum Gal-3 and urinary Gal-3 (uGal-3/cr) were associated with the estimated glomerular filtration rate (R = -0.359, p < 0.001; R = -0.285, p < 0.001). Serum Gal-3 was not linked to all-cause mortality [HR 1.17 (CI 0.96-1.42)] over 9.2 years. However, uGal-3/cr was associated with all-cause mortality [HR 1.60 (CI 1.31-1.95)]. This association sustained multivariable adjustment for cardiovascular risk factors and renal function [HR 1.71 (CI 1.35-2.17)].

CONCLUSIONS

This study is the first to show an association of uGal-3/cr and long-term mortality in patients with PAD. Gal-3 was not predictive of long-term mortality but seems to be a marker of PAD severity in patients without critical limb ischemia.

Arterial stiffness in acute COVID-19 and potential associations with clinical outcome

BACKGROUND

Coronavirus disease 2019 (COVID-19) interferes with the vascular endothelium. It is not known whether COVID-19 additionally affects arterial stiffness.

METHODS

This case-control study compared brachial-ankle pulse wave (baPWV) and carotid-femoral pulse wave velocities (cfPWV) of acutely ill patients with and without COVID-19.

RESULTS

Twenty-two COVID-19 patients (50% females, 77 [67-84] years) were compared with 22 age- and sex-matched controls. In COVID-19 patients, baPWV (19.9 [18.4-21.0] vs. 16.0 [14.2-20.4], P = 0.02) and cfPWV (14.3 [13.4-16.0] vs. 11.0 [9.5-14.6], P = 0.01) were higher than in the controls. In multiple regression analysis, COVID-19 was independently associated with higher cfPWV (β = 3.164, P = 0.004) and baPWV (β = 3.532, P = 0.003). PWV values were higher in nonsurvivors. In survivors, PWV correlated with length of hospital stay.

CONCLUSION

COVID-19 appears to be related to an enhanced PWV reflecting an increase in arterial stiffness. Higher PWV might be related to an increased length of hospital stay and mortality.

Angiogenin-A Proposed Biomarker for Cardiovascular Disease-Is Not Associated With Long-Term Survival in Patients With Peripheral Artery Disease

We evaluated angiogenin as a prospective biomarker in peripheral artery disease (PAD) patients with and without claudication symptoms. A pilot study suggested an elevation of angiogenin in critical limb ischemia. However, in PAD patients, the predictive value of angiogenin has not yet been evaluated. For this purpose, 342 patients with PAD (age: 69 ± 10 years, 34.5% women) were followed-up for 7 years in a cross-sectional study. Angiogenin was measured by enzyme-linked immunosorbent assay. All-cause and cardiovascular mortality were analyzed by Cox regression. Angiogenin levels were higher in men (P = .001) and were associated with patient waist-to-hip ratio (P < .001), fasting triglycerides (P = .011), and inversely with estimated glomerular filtration rate (P = .009). However, angiogenin showed no association with age, characteristics of diabetes, markers of lipid metabolism, or C-reactive protein. Angiogenin did not correlate with markers of angiogenesis such as vascular endothelial growth factor, angiopoietin-2, or tie-2. Furthermore, angiogenin was not associated with PAD Fontaine stages or with patient ankle-brachial index in addition to all-cause mortality (hazard ratio [HR] = 1.09 [95% CI: 0.89-1.34]) or cardiovascular morality (HR = 1.05 [0.82-1.35]). These results suggest that angiogenin does not provide further information regarding outcome prediction in patients with PAD.

Micro- and macrovascular function in patients suffering from primary adrenal insufficiency: a cross-sectional case-control study

BACKGROUND

Despite adequate glucocorticoid (GC) and mineralocorticoid (MC) replacement therapy, patients suffering from primary adrenal insufficiency (AI) have an increased mortality, mainly due to cardiovascular diseases. Only little knowledge exists on the contribution of MC substitution to the cardiovascular risk. Therefore, this study investigates the impact of plasma renin concentration on parameters of micro- and macrovascular function.

METHODS

26 patients with primary AI [female = 18, age: 51 (28; 78) years; BMI: 24 (18; 40) kg/m²; disease duration: 18 (5; 36) years] were included in this cross-sectional analysis. Intima media thickness (IMT) and pulse wave velocity (PWV) were investigated to assess macrovascular remodeling and arterial stiffness. Microvascular function was estimated by post-occlusive reactive hyperemia using laser Doppler fluxmetry. Baseline perfusion, biological zero, peak perfusion, time to peak and recovery time were recorded. Patients were grouped according to their median plasma renin concentration of previous visits (Renin_high vs Renin_low) and were compared to a group of healthy women [age: 44 (43; 46) years; BMI: 24.2 (21.8; 27.5)].

RESULTS

PWV was significantly higher in AI patients compared to controls [9.9 (5; 18.5) vs 7.3 (6.8; 7.7) m/s; p < .01], whereas no differences in microvascular function could be found. In Renin_low time to peak perfusion was significantly longer [6.0 (3; 15) vs 3.5 (1.5; 11) s; p < .05], whereas no differences in IMT and PWV were observed between Renin_high and Renin_low. No impact of GC dose was observed.

CONCLUSIONS

Microvascular function is not impaired in patients with primary AI under adequate replacement therapy, although higher renin concentrations are associated with subclinical improvements. No relation between RAAS activity and macrovascular function is observed, while arterial stiffness might be increased in primary AI.

Vascular peroxidase 1 is independently associated with worse kidney function in patients with peripheral artery disease

BACKGROUND

Oxidative stress is involved in cardiovascular disease such as peripheral artery disease (PAD). Vascular Peroxidase 1 (VPO1), a novel heme-containing peroxidase mainly expressed in the cardiovascular system, aggravates oxidative stress. Evidence in humans is limited. Current work aims to measure VPO1 in patients suffering from PAD, and to evaluate the association of VPO1 with conventional markers of cardiovascular risk factors (CVRF), including the estimated glomerular filtration rate (eGFR) and albuminuria categories.

METHODS

This study is part of a longitudinal observational study. At baseline, 236 PAD-patients were included. VPO1 plasma levels (ng/mL) were measured by commercially available ELISA kits. A two-sided p level of < 0.05 was considered statistically significant.

RESULTS

In the cross-sectional analysis (n = 236), VPO1 associated with ageing (p = 0.035) as well as with eGFR and albuminuria category, the markers of chronic kidney disease (CKD)-progression (p = 0.042). The longitudinal 18-months follow-up analysis (n = 152) demonstrated that baseline VPO1 predicts rapid kidney function decline (RKFD) (n = 49), defined as more than - 3 mL/min/1.73m2 eGFR loss per year, (OR per one SD VPO1 1.60 (1.11-2.30); p = 0.009). This association between VPO1 and kidney function withstood the multivariable adjustment for traditional CVRF including baseline eGFR and urine albumin-to-creatinine ratio (UACR), (adjOR per one SD VPO1 1.73 (1.14-2.61); p = 0.046).

CONCLUSION

This study is first to reveal that VPO1 is independently associated with declining kidney function in patients with PAD. VPO1 shows a tighter association to kidney function than to other CVRF. This finding points to VPO1 as a potential target protein to assess CKD-progression.

Thromboangiitis Obliterans Biomarker Shifts in Different Acute Phase Stages: A Case Study

Thromboangiitis obliterans (TAO) is a rare vasculopathy that is predominantly seen in young male smokers. Recently, new biomarkers have been shown to be useful in distinguishing TAO from acute phase TAO in an Asian study population. The present case study illustrates their application in a European patient during TAO exacerbation and their association with therapeutic performance.

Soluble urokinase-type plasminogen activator receptor predicts peripheral artery disease severity and outcomes

Soluble urokinase-type plasminogen activator receptor (suPAR) is associated with chronic kidney disease (CKD) severity and peripheral artery disease (PAD). We hypothesize an association of PAD severity and suPAR in patients without advanced CKD and further risk stratification according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. For study purposes, suPAR was measured in 334 PAD patients (34% women, age 69 (62–78) years, eGFR 68 ± 20 mL/min/1.72 m²) by commercial ELISA. Patients were followed for 10 years to assess long-term all-cause survival by Cox regression. Higher suPAR levels were associated with lower ankle–brachial index (R = −0.215, p = 0.001) in patients with PAD without media-sclerosis (n = 236). suPAR levels inversely correlated with decreased glomerular filtration rate (R = −0.476, p < 0.001) and directly correlated with urinary albumin-to-creatinine ratio (R = 0.207, p < 0.001). Furthermore, higher suPAR levels associated with a higher KDIGO risk score (p < 0.001). Baseline suPAR was significantly associated with all-cause mortality (HR 1.40 (95% CI 1.16–1.68), p < 0.001) over 10 years. suPAR remained associated with mortality (HR 1.29 (1.03–1.61), p = 0.026) after multivariable adjustment for age, sex, cardiovascular risk factors, and eGFR. Future research may define a standard role for suPAR assessment in PAD’s work-up and treatment, especially in patients with CKD.

GlycA for long-term outcome in T2DM secondary prevention

AIMS

Glycosylated acetyls (GlycA), a systemic marker of inflammation, were associated both with incident type 2 diabetes mellitus (T2DM) and incident cardiovascular (CV) disease. This study evaluates the predictive value of GlycA for long-term survival in patients with T2DM and peripheral artery disease (PAD).

METHODS

GlycA (mmol/l) levels were measured by nuclear magnetic resonance spectroscopy in a cross-sectional cohort of patients with PAD (n = 319). Both all-cause and CV mortality were evaluated after a follow-up of 9.0 (IQR 6.5-9.5) years. During the follow-up 117 patients died, of those 64 events were of CV origin (PAD-T2DM subgroup: all-cause mortality n = 60, CV-mortality n = 32).

RESULTS

PAD-T2DM showed a tendency towards a worse CV risk factor profile and a higher percentage of known coronary artery disease (24.9% vs 43.5%, p < 0.001). GlycA levels were higher in PAD-T2DM (1.6 ± 0.2 vs. 1.53 ± 0.18, p = 0.002). GlycA predicted all-cause mortality after multivariable adjustment for traditional CV risk factors (HR for 1 SD increase 1.51, 95% confidence interval 1.03-2.19) in PAD-T2DM, while no association could be seen with CV-mortality (1.22, 0.73-2.06).

CONCLUSIONS

GlycA was capable of predicting long-term outcome in PAD patients with T2DM. Thus, GlycA might reflect the added inflammatory burden of T2DM in systemic atherosclerosis.

Comparison of Light Transmission Aggregometry With Impedance Aggregometry in Patients on Potent P2Y12 Inhibitors

Since data on the agreement between light transmission aggregometry (LTA) and multiple electrode aggregometry (MEA) in patients on the more potent P2Y₁₂ inhibitors are missing so far, we investigated if the evaluation of the responsiveness to therapy by LTA can be replaced by MEA in 160 acute coronary syndrome (ACS) patients on dual antiplatelet therapy with aspirin and prasugrel or ticagrelor (n = 80 each). Cut-off values for high on-treatment residual platelet reactivity (HRPR) in response to adenosine diphosphate (ADP) or arachidonic acid (AA) were defined according to previous studies showing an association of HRPR with the occurrence of adverse ischemic outcomes. ADP- inducible platelet aggregation was 33% and 37% (P = 0.07) by LTA and 19 AU and 20 AU (P = 0.38) by MEA in prasugrel- and ticagrelor-treated patients, respectively. AA- inducible platelet aggregation was 2% and 3% by LTA and 15 AU and 16 AU by MEA, (all P ≥ 0.3) in patients on prasugrel and ticagrelor, respectively. By LTA, HRPR ADP and HRPR AA were seen in 5%/5% and in 4%/ 13% of patients receiving prasugrel- and ticagrelor, respectively. By MEA, HRPR ADP and HRPR AA were seen in 3%/ 25% and 0%/24% of prasugrel- and ticagrelor-treated patients, respectively. ADP-inducible platelet reactivity by MEA correlated significantly with LTA ADP in prasugrel-treated patients (r = 0.4, P < 0.001), but not in those receiving ticagrelor (r = 0.09, P = 0.45). AA-inducible platelet aggregation by LTA and MEA did not correlate in prasugrel- and ticagrelor-treated patients. Sensitivity/specificity of HRPR by MEA to detect HRPR by LTA were 25%/99% for MEA ADP and 100%/79% for MEA AA in prasugrel-treated patients, and 0%/100% for MEA ADP and 70%/83% for MEA AA in ticagrelor-treated patients. In conclusion, on-treatment residual ADP-inducible platelet reactivity by LTA and MEA shows a significant correlation in prasugrel- but not ticagrelor-treated patients. However, in both groups LTA and MEA revealed heterogeneous results regarding the classification of patients as responders or non-responders to P2Y₁₂ inhibition.

Ticagrelor Inhibits Toll-Like and Protease-Activated Receptor Mediated Platelet Activation in Acute Coronary Syndromes

Purpose

Since ticagrelor inhibits the cellular uptake of adenosine, thereby increasing extracellular adenosine concentration and biological activity, we hypothesized that ticagrelor has adenosine-dependent antiplatelet properties. In the current study, we compared the effects of ticagrelor and prasugrel on platelet activation in acute coronary syndrome (ACS).

Methods

Platelet surface expression of P-selectin and activated glycoprotein (GP) IIb/IIIa in response to adenosine diphosphate (ADP), the toll-like receptor (TLR)-1/2 agonist Pam3CSK4, the TLR-4 agonist lipopolysaccharide (LPS), the protease-activated receptor (PAR)-1 agonist SFLLRN, and the PAR-4 agonist AYPGKF were measured by flow cytometry in blood from 80 ticagrelor- and 80 prasugrel-treated ACS patients on day 3 after percutaneous coronary intervention. Residual platelet aggregation to arachidonic acid (AA) and ADP were assessed by multiple electrode aggregometry and light transmission aggregometry.

Results

ADP-induced platelet activation and aggregation, and AA-induced platelet aggregation were similar in patients on ticagrelor and prasugrel, respectively (all p ≥ 0.3). Further, LPS-induced platelet surface expression of P-selectin and activated GPIIb/IIIa did not differ significantly between ticagrelor- and prasugrel-treated patients (both p > 0.4). In contrast, Pam3CSK4-induced platelet surface expression of P-selectin and activated GPIIb/IIIa were significantly lower in ticagrelor-treated patients (both p ≤ 0.005). Moreover, SFLLRN-induced platelet surface expression of P-selectin and activated GPIIb/IIIa were significantly less pronounced in patients on ticagrelor therapy compared to prasugrel-treated patients (both p < 0.03). Finally, PAR-4 mediated platelet activation as assessed by platelet surface expression of activated GPIIb/IIIa following stimulation with AYPGKF was significantly lower in patients receiving ticagrelor (p = 0.02).

Conclusion

Ticagrelor inhibits TLR-1/2 and PAR mediated platelet activation in ACS patients more strongly than prasugrel.

Predictive power of novel and established obesity indices for outcome in PAD during a five-year follow-up

BACKGROUND AND AIMS

Previous data show contradicting results regarding relevance of obesity on outcome in peripheral arterial disease (PAD). Thus, this study aims to evaluate the predictive power of obesity as measured by established and novel obesity indices (waist circumference WC, waist-hip ratio WHR, body-mass index BMI, body adiposity index BAI, visceral adiposity index VAI, weight-adjusted waist index WWI) in a PAD cohort.

METHODS AND RESULTS

In 367 patients with diagnosed PAD anthropometric parameters were assessed at study inclusion in an observational study. Mortality data was retrieved from the central death registry after five years. Outcome analyses were performed by multivariable Cox-regression models. 57 PAD patients (15.5%) died during the follow-up, of those 36 were categorized as cardiovascular origin. Patients from the all-cause mortality group were older, more often diabetics with a worse glucose control and had worse renal function. Obesity indices were not significantly different between the event and control group. None of the evaluated risk factors predicted cardiovascular or all-cause death after multivariable adjustment for age, gender, LDL-C, serum creatinine, systolic blood pressure, CRP, smoking habits, diabetes status and previous history of peripheral revascularisation (all-cause WC 1.007 (0.983-1.031), WHR 1.772 (0.106-29.595), BMI 1.006 (0.939-1.078), BAI 1.002 (0.945-1.063), VAI 1.019 (0.895-1.161), WWI 1.085 (0.831-1.416); cv-death WC 1.007 (0.978-1.036), WHR 0.382 (0.006-25.338), BMI 1.004 (0.918-1.098), BAI 1.034 (0.959-1.116), VAI 1.036 (0.885-1.213), WWI 1.061 (0.782-1.441)).

CONCLUSION

Obesity as risk marker estimated by indices both for general and visceral adiposity, does not predict mortality in a secondary prevention cohort of PAD patients.

Peripheral arterial disease and type 2 diabetes: Older patients still exhibit a survival benefit from glucose control

OBJECTIVE

To investigate a possible beneficial effect of strict glycaemic control on all-cause mortality in patients with peripheral arterial disease and type 2 diabetes mellitus.

METHODS

A total of 367 mainly older peripheral arterial disease patients [age: 69 (62-78) years, 34% women, Fontaine stage I-II] were categorized according to glycaemic control, that is, (a) no type 2 diabetes mellitus, (b) strict glucose control (HbA1c < 53 mmol/mol) and (c) lenient glucose control (HbA1c ⩾ 53 mmol/mol) at inclusion and by mean HbA1c over the first study year. Mortality was analysed using Kaplan-Meier and Cox-regression analyses after 7 years.

RESULTS

The combination of type 2 diabetes mellitus and peripheral arterial disease reduced survival from 78.8% to 68.9% in comparison to patients without type 2 diabetes mellitus (p = 0.023). Patients with strict glucose control (75%) were associated with increased survival in comparison to patients with lenient glucose control (58.9%) stratified by mean HbA1c (p = 0.042). Baseline cardiovascular risk factors were similar in those type 2 diabetes mellitus patients. In this peripheral arterial disease cohort HbA1c (hazard ratio: 1.3, 1.04-1.63), age (hazard ratio: 1.7, 1.3-2.3) and C-reactive protein (hazard ratio: 1.5, 1.2-2.0) remained independent associates for mortality adjusted for cardiovascular risk factors and diabetes duration.

CONCLUSION

Older patients with peripheral arterial disease and type 2 diabetes mellitus still benefit from strict glucose control in a cohort of patients with similar distribution of cardiovascular risk factors.

Acute Limb Ischemia after Intake of the Phenylethylamine Derivate NBOMe

Objective: N-(2-methoxy) benzyl-phenethylamine (NBOMe) derivatives have a high affinity to the serotonin receptor 2A and emerged as new psychedelic agents. We report the case of a 30-year-old man admitted to the hospital because of acute ischemia of the left arm with clinical symptoms of pallor, pulselessness, paresthesia, and a motoric deficit. The patient had a history of schizophrenia and drug abuse and disclosed during the hospital stay the sublingual intake of a substance bought as 25I-NBOMe the night before the ischemic event. Methods: Routine clinical diagnostics including among others color-coded duplex sonography and computed tomography angiography (CTA) were performed. The remainder of the drugs was analyzed using high performance liquid chromatography. Results: Initial color-coded duplex sonography of the upper left limb showed pathological flow profiles of the axillary, brachial, ulnar, and radial artery with a reduced diameter of the ulnar (0.9 mm) and radial (1.1 mm) artery. In consequence, peripheral vasospasm, distal arterial thrombosis, or arterial embolization was anticipated. As therapeutic measures, the patient immediately received intravenous systemic vasodilators (alprostadil) and therapeutic anticoagulation with low molecular weight heparin. Instant symptom improvement was observed within the first day after therapy initiation. The subsequently performed CTA of the heart and left arm showed no signs of thrombotic material. Treatment was continued for five days and the patient was released thereafter having completely normalized perfusion in his left arm. Outpatient treatment was continued with calcium-channel blockers, as the patient had also displayed arterial hypertension. Drug analysis retrieved a composition of the isomers 25I-NBOMe, 25C-NBOMe, and 25H-NBOMe as well as traces of pentylon. Conclusion: NBOMe ingestion implicates the risk of peripheral vasospasms with severe, limb-threatening ischemia.

α-Hydroxybutyrate dehydrogenase is associated with atherothrombotic events following infrainguinal angioplasty and stenting

Besides clinical characteristics, easy-accessible laboratory markers could be of value to refine risk stratification in peripheral artery disease. In the current study, we investigated whether α-hydroxybutyrate dehydrogenase (HBDH) is associated with atherothrombotic events in 83 stable patients undergoing infrainguinal angioplasty and stenting. The primary endpoint was defined as the composite of the first occurrence of nonfatal myocardial infarction, nonfatal stroke or transient ischemic attack and cardiovascular death within 2 years after angioplasty and stenting, and occurred in 6 patients (7.2%). HBDH levels at baseline were significantly higher in patients who subsequently developed the primary endpoint (126 U/L [116–137 U/L] vs. 105 U/L [95–120 U/L]; p = 0.04). ROC curve analysis revealed that HBDH could distinguish between patients without and with future atherothrombotic events. A HBDH concentration ≥ 115 U/L was identified as the best threshold to predict the composite endpoint, providing a sensitivity of 83.3% and a specificity of 71.4%, and was therefore defined as high HBDH. High HBDH was seen in 28 patients (33.7%). Ischemic events occurred significantly more often in patients with high HBDH than in patients with lower HBDH levels (5 vs. 1 patients, p = 0.007). In conclusion, HBDH is associated with the occurrence of atherothrombotic events after infrainguinal angioplasty with stent implantation. Future trials are warranted to study the predictive role of HBDH for ischemic outcomes and to investigate underlying mechanisms.

P1960Endothelial progenitor cells are associated with cardiovascular outcome in patients with peripheral artery disease

Background and introduction

Endothelial dysfunction and associated cells are an important cornerstone in the development and progression of peripheral artery disease (PAD). Endothelial progenitor cells (EPC) are released from the bone marrow and have exhibited the potential for cardiovascular repair. Higher EPC levels have been linked to longer event-free survival in coronary artery disease. Similar evaluation of EPC on mortality in PAD is lacking.

Purpose

The current study aimed to evaluate the possible association between EPC levels and mortality in PAD patients.

Methods

EPC were measured in 367 PAD patients (age 69.22±10.3, 66.5% male, Fontaine stage I-II) by flow cytometry using the cell surface marker CD34+ and CD309+. Patients were followed for seven years to assess all cause and cardiovascular mortality. Patients were categorized into quartiles according to EPC levels for further analyses. Statistics included Kaplan-Meier and Cox regression.

Results

89 patients died over the observation period. ICD-codes indicated a cardiovascular cause in 58 patients. The group with the highest count of EPC showed a trend towards higher all-cause mortality (p=0.070) and a significant association with cardiovascular mortality (p=0.002). Multivariable adjustment for age, c-reactive protein, systolic blood pressure, renal function (creatinine and urinary albumin), low density lipoprotein cholesterol, HbA1c, and smoking status revealed the EPC quartile to be an independent risk factor for cardiovascular mortality (p=0.016).

Conclusion

Increased levels of CD34+CD309+ cells are independently associated with long-term cardiovascular mortality in PAD patients.

Protease-activated receptor-mediated platelet aggregation in acute coronary syndrome patients on potent P2Y12 inhibitors

BACKGROUND

Despite the increasing use of potent P2Y12 inhibitors, further atherothrombotic events still impair the prognosis of many acute coronary syndrome (ACS) patients. This may in part be attributable to intact platelet aggregation via the human thrombin receptors protease-activated receptor (PAR)-1 and PAR-4.

OBJECTIVE

We studied PAR mediated platelet aggregation in ACS patients following percutaneous coronary intervention (PCI) with stent implantation in a cross-sectional study.

METHODS

Platelet aggregation to ADP as well as to the PAR-1 agonist SFLLRN and the PAR-4 agonist AYPGKF was assessed by multiple electrode aggregometry in 194 ACS patients on dual antiplatelet therapy with aspirin and either prasugrel (n = 114) or ticagrelor (n = 80) 3 days after PCI.

RESULTS

Based on the consensus cutoff value, high on-treatment residual platelet reactivity to ADP (HRPR ADP) was observed in only 2 prasugrel-treated patients. Both patients with HRPR ADP had also a normal response to SFLLRN and AYPGKF. Among the 112 prasugrel-treated patients with adequate P2Y12 inhibition, 50 patients (45%) still had a normal response to SFLLRN, and 70 patients (63%) still had a normal response to AYPGKF. Among the 80 ticagrelor-treated patients with adequate P2Y12 inhibition, 25 patients (31%) still had a normal response to SFLLRN, and 50 (63%) still had a normal response to AYPGKF.

CONCLUSION

Normal platelet aggregation via PAR-1 and PAR-4 is preserved in many patients with adequate P2Y12 inhibition by prasugrel and ticagrelor. The present findings may at least in part explain adverse ischemic events despite potent P2Y12 inhibition.

Thrombospondin-4 increases with the severity of peripheral arterial disease and is associated with diabetes

Thrombospondin-4 (TSP-4) is an extracellular matrix protein of the vessel wall. Despite bench evidence, its significance in the clinical setting of atherosclerosis is missing. TSP-4 (ng/ml) was measured in 365 PAD patientsusing a commercially available ELISA. PAD was diagnosed by the ankle–brachial index (ABI) and clinically graded using the Fontaine classification. TSP-4 levels were significantly higher in Fontaine II vs. Fontaine I (4.78 ± 0. 42, 4.69 ± 0.42, p = 0.043). TSP-4 significantly correlated with ABI (r = − 0.141, p = 0.023, n = 259) after the exclusion of mediasclerotic patients. Binary logistic regression analysis for Fontaine I vs. II showed an OR of 1.70 (1.02–2.82) in a multivariable model adjusted for traditional risk factors. Interestingly, TSP-4 levels were higher in patients with type 2 diabetes mellitus or prediabetes (DGT) compared with normal glucose tolerance (NGT) (4.76 ± 0.42 vs. 4.66 ± 0.41, p = 0.035). ANOVA for PAD and diabetes subgroups showed a linear increase with disease burden with the highest difference between Fontaine I-NGT and Fontaine II-DGT (4.59 ± 0.40, 4.79 ± 0.43, p = 0.015). TSP-4 levels increased with PAD severity and showed a former unknown association with diabetes. Thus, TSP-4 could be a novel marker of atherosclerotic activity, especially in the major subgroup of patients with concomitant diabetes.

D-Dimer and TAT Measurement in Patients with Deep Venous Thrombosis: Utility in Diagnosis and Judgement of Anticoagulant Treatment Effectiveness

The plasma levels of thrombin-antithrombin III-complexes (TAT) and the fibrin split product D-Dimer were measured in 39 patients with phlebographically proven acute DVT: 34 patients had proximal DVT, 5 had calf DVT The sensitivity of D-Dimer and TAT measurements in the diagnosis of proximal DVT was found to be dependent on the duration of symptoms: 0 to 7 days (n = 27): elevated D-Dimer levels (>120 ng/ml) = 1, D-Dimer Latex test positive (>500 ng/ml) = 1, elevated TAT levels (>6 ng/ml) = 0.88. Eight to 14 days (n = 7): elevated D-Dimer levels = 1, D-Dimer Latex test positive = 0.33, elevated TAT levels = 0.66; specificity: elevated D-Dimer: 0.48, D-Dimer Latex test: 1, elevated TAT: 0.76. Calf DVT patients (n = 5) had elevated D-Dimer levels, negative Latex tests and 3 of them had normal TAT values. Hemostatic and fibrinolytic parameters were also determined in 13 patients during heparin treatment of proximal DVT. Elevated D-Dimer and TAT levels rapidly decreased after initiation of anticoagulant therapy. In 2 of 13 patients a marked increase in D-Dimer and TAT levels was observed in periods of ineffective heparinization, documented by normal or only slightly prolonged thrombin clotting times. We conclude from our results that 1) D-Dimer El A measurement, in contrast to TAT measurement, shows a very high sensitivity in the diagnosis of DVT, 2) due to low specificity this test can only be used to exclude thrombosis in patients with suspected DVT, and 3) the determination of the plasma levels of D-Dimer and TAT may be useful for judging the effect of anticoagulant treatment on thrombotic processes.

D-Dimer in Local Thrombolytic Therapy with Low Doses of Recombinant Human Tissue-Type Plasminogen Activator (rt-PA) in Patients with Peripheral Arterial Occlusive Disease

The generation of D-dimer was studied in the course of local thrombolytic therapy of peripheral arterial occlusions with low doses of recombinant human tissue-type plasminogen activator (rt-PA) in 7 patients. Intermittent local application of rt-PA resulted in a marked increase in D-dimer exceeding values usually seen after intravenous application of manifold higher doses used in myocardial infarction. The increase in D-dimer was related to the estimated thrombus size (length of the occlusion) and the total dose of rt-PA applied. During local rt-PA infusion 6 of 7 patients maintained plasminogen activator inhibitor capacity (PAI-cap) between 34% and 79% of their corresponding pre-treatment levels; detectable levels of PAI-cap in circulating blood during the procedure did not interfere with the success of therapy.

Variable Platelet Response to Low-dose ASA and the Risk of Limb Deterioration in Patients Submitted to Peripheral Arterial Angioplasty

A group of 100 patients with intermittent claudication (70 male, 30 female), treated with 100 mg ASA per day, were followed over 18 months after elective percutaneous balloon angioplasty. Platelet function was monitored over a period of 12 months by corrected whole blood aggregometry (CWBA). Upon stimulation by arachidonic acid (AA), adenosine diphosphate (ADP) and collagen, CWBA-results were obtained by an electronic acquisition and evaluation system correcting for hematocrit and platelet count of the blood sample.

All patients showed a completely inhibited platelet response to AA stimulation. Comparison of the CWB A-results with clinical parameters revealed that reocclusions at the site of angioplasty occurred exclusively in male patients for which CWBA failed to prove an inhibition of aggregation upon both agonists, ADP and collagen, and for these patients the risk of complication is at least 87% higher (p = 0.0093).

Only 40% of male patients show the expected effect of ASA on in vitro platelet aggregation at any given point in time and CWBA is capable of predicting those male patients which are at an elevated risk of reocclusion following peripheral angioplasty.

YKL-40 levels increase with declining ankle-brachial index and are associated with long-term cardiovascular mortality in peripheral arterial disease patients

BACKGROUND AND AIMS

YKL-40 is an inflammatory marker secreted by macrophages and is expressed in atherosclerotic plaques. YKL-40 increases in coronary artery disease (CAD) with poor coronary collateral vessel development. Higher levels are linked to reduced survival in CAD patients. Studies evaluating YKL-40 in patients with peripheral arterial disease (PAD) are scarce. This study aims to elucidate a possible link between YKL-40 and PAD severity as well as cardiovascular long-term mortality.

METHODS

YKL-40 was measured at baseline in 365 elderly PAD patients (age 69 ± 10.4, 33.7% women, Fontaine stage I-II) by bead-based multiplex assay. Patients were followed for seven years to assess long-term cardiovascular and all-cause survival by Kaplan-Meier and Cox regression.

RESULTS

YKL-40 levels were associated with declining ankle-brachial index (ABI) in PAD patients without Moenckeberg's mediasclerosis (R = -0.189, p=0.002). PAD patients with mediasclerosis exhibited higher YKL-40 levels (p=0.002). Baseline YKL-40 levels were significantly associated with cardiovascular mortality (HR 1.52 (1.21-1.91), p < 0.001) and all-cause mortality (HR 1.45 (1.20-1.75), p < 0.001) over a seven-year observation period. After multivariable adjustment for gender, patient age, known carotid artery disease, known coronary artery disease, smoking status, systolic blood pressure, HbA_1c, low density lipoprotein cholesterol, estimated glomerular filtration rate, aspartate aminotransferase, and C-reactive protein, YKL-40 remained significantly associated with cardiovascular (HR 1.34 (1.02-1.75), p=0.033) and all-cause mortality (HR 1.25 (1.01-1.55), p=0.039).

CONCLUSIONS

Increased YKL-40 levels are independently associated with poor long-term cardiovascular survival in peripheral arterial disease patients. Furthermore, YKL-40 correlates with patients' ABI in PAD in the absence of mediasclerosis.

Angiopoietin-2 and Survival in Peripheral Artery Disease Patients

Survival of peripheral arterial disease (PAD) patients increased over the last decade due to increased use of secondary preventive medication and rapid revascularization of PAD patients. Angiogenetic markers such as vascular endothelial growth factor (VEGF), angiopoietin-2 (Ang-2) and its receptor Tie-2 might be useful markers to assess the residual risk for mortality in PAD patients. The aim of this study was to evaluate angiogenetic markers for the prediction of mortality in a PAD cohort. For this purpose, 366 patients (mean age: 69 ± 10 years) with PAD Fontaine stage I or II were included and followed up over a 5-year study period. Serum Ang-2, Tie-2 and VEGF levels were measured by bead-based multiplex assay. All-cause mortality and major cardiovascular events (MACE) including all-cause death, non-fatal stroke and non-fatal myocardial infarction were analysed by Kaplan–Meier and Cox regression analyses after 5 years. Ang-2 was associated with Tie-2 (R = 0.151, p = 0.006) and VEGF levels (R = 0.160, p = 0.002). However, only Ang-2 was linked to all all-cause mortality in PAD patients (hazard ratio [HR]: 1.55 [1.23–2.15], p = 0.008) even after adjustment for age and gender, haemoglobin A1c, low-density lipoprotein cholesterol, systolic blood pressure and glomerular filtration rate (HR: 1.44 [1.03–2.00], p = 0.032). Furthermore, an association of Ang-2 and MACE in PAD patients (HR: 1.36 (1.03–1.78), p = 0.028) was found. This result implies that Ang-2 might be used as an additional marker to stratify PAD patients to predict poor mid-term life expectancy.

Chronic inflammation predicts long-term mortality in patients with Raynaud's phenomenon

BACKGROUND

Subclinical chronic inflammation could be the driving force behind the recently revealed association between abnormal nailfold capillaries as well as autoantibodies and long-term mortality in patients with incipient Raynaud's phenomenon. Whether laboratory markers that reflect a chronic inflammatory process are directly related to mortality in Raynaud's phenomenon is not known.

METHODS

In total, 2958 patients with incipient Raynaud's phenomenon without previously known connective tissue disease (CTD) were enrolled. At their initial presentation, laboratory tests for C-reactive protein (CRP), leucocytes, fibrinogen and the haemoglobin concentration were obtained. In addition, nailfold capillaries and antinuclear antibodies (ANA) were assessed. Patients' mortality was recorded through a median follow-up period of 9.3 years.

RESULTS

Baseline CRP, fibrinogen and haemoglobin concentration were associated with long-term mortality in an individual analysis of patients with incipient Raynaud's phenomenon. In a multivariable model including patients' age, nailfold capillaries and ANA, a low haemoglobin concentration remained independently related to future mortality. Amongst potential predictors for mortality in patients with Raynaud's phenomenon, a low haemoglobin concentration was most strongly related to patients' mortality risk.

CONCLUSION

In Raynaud's phenomenon, laboratory markers that can be attributed to a chronic inflammatory state independently yield prognostic information in addition to the presence of abnormal nailfold capillaries and ANA. Amongst all prognostic markers, the haemoglobin concentration is most strongly related to patients' mortality in Raynaud's phenomenon.

Low Levels of High-Density Lipoprotein Cholesterol Are Linked to Impaired Clopidogrel-Mediated Platelet Inhibition

Low high-density lipoprotein cholesterol (HDL-C) levels are an independent predictor of ischemic events in patients with atherosclerotic cardiovascular disease. This may in part be due to decreased clopidogrel-mediated platelet inhibition in patients with low HDL-C. We investigated the association of HDL-C with on-treatment platelet reactivity to adenosine diphosphate (ADP) in 314 patients on dual antiplatelet therapy with clopidogrel and aspirin undergoing angioplasty and stenting. Platelet P-selectin expression was assessed by flow cytometry, and platelet aggregation was determined by the VerifyNow P2Y₁₂ assay and the Impact-R. High-density lipoprotein cholesterol levels were inversely associated with P-selectin expression and the VerifyNow P2Y₁₂ assay (both P ≤ .01). Moreover, we found a positive correlation of HDL-C with surface coverage by the Impact-R ( P = .003). Patients with low HDL-C (≤35 mg/dL) exhibited a significantly higher P-selectin expression in response to ADP and higher platelet aggregation by the VerifyNow P2Y₁₂ assay and the Impact-R than patients with normal HDL-C (>35 mg/dL; all P < .05). High on-treatment residual platelet reactivity by the VerifyNow P2Y₁₂ assay occurred significantly more frequently in patients with low HDL-C levels than in those with normal HDL-C (47.4% vs 30.1%, P = .01). In conclusion, low HDL-C is linked to impaired clopidogrel-mediated platelet inhibition after angioplasty and stenting.

Sublingual functional capillary rarefaction in chronic heart failure

BACKGROUND AND OBJECTIVE

Microcirculatory changes contribute to clinical symptoms and disease progression in chronic heart failure (CHF). A depression of coronary flow reserve is associated with a lower myocardial capillary density in biopsies. We hypothesized that changes in cardiac microcirculation might also be reflected by a systemic reduction in capillaries and visualized by sublingual videomicroscopy. The aim was to study in vivo capillary density and glycocalyx dimensions in patients with CHF vs healthy controls.

METHODS

Fifty patients with ischaemic and nonischaemic CHF and standard treatment were compared to 35 healthy age-matched subjects in a prospective cross-sectional study. Sublingual microcirculation was visualized using a sidestream darkfield videomicroscope. Functional and perfused total capillary densities were compared between patients and controls. A reduced glycocalyx thickness was measured by an increased perfused boundary region (PBR).

RESULTS

Median functional and total perfused capillary densities were 30% and 45% lower in patients with CHF (both P < .001). Intake of oral vitamin K antagonists was associated with significantly lower capillary densities (P < .05), but not independent of NT-proBNP. Dimensions of the glycocalyx were marginally lower in CHF patients than in healthy controls (<7% difference). However, PBR correlated significantly with inflammation markers (fibrinogen: r = .58; C-reactive protein: r = .42), platelet counts (r = .36) and inversely with measures of liver/renal function such as bilirubin (r = -.38) or estimated glomerular filtration rate (r = -.34) in CHF patients.

CONCLUSION

CHF patients have got a markedly lower functional and total perfused capillary density in sublingual microvasculature when compared to controls, indicating a systemic decrease in microcirculation.